cambrian trilobites from northern victoria land, antarctica

8/14/2019 Cambrian trilobites from Northern Victoria Land, Antarctica

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New Zealand Journal of Geology and Geophysics, 1996, Vol. 39 : 3633870028 -8306 /96/39 03-03 63 $2.50/0 The Royal Society of New Zealand 1996 363

Cambrian trilobites from Northern Victoria Land, Antarctica, and theirstratigraphic implications

R. A. COOPER 1J. B. JAGO 2J. G. BEGG 1

'institute of Geological & Nuclear SciencesP.O. Box 30368Lower Hutt, New Zealand2Department of Applied GeologyGartrell School of Mining, Metallurgy and Applied

GeologyUniversity of South AustraliaThe Levels, South Australia 5095

Abstract Fifty-four trilobite taxa from 15 new localitiesin the Bow ers Terrane of Northern Victoria Land, includingthe first fossils from Molar Formation, are described. Thefossils indicate an age range from late Middle Cambrian(Boomerangian or older) to mid Late Cambrian ( lateIdamean). At Reilly Ridge, the Spurs Formation crops outin a number of fault-bounded slices; the new fossils indicatemarked lateral facies contrasts between slices and suggestconsiderable lateral displacement along the bounding faults.At Houliston Glacier, trilobites of Mindyallan age in MolarFormation imply that the boundary between the Molar andSpurs Formations is strongly time transgressive. New speciesdescribed in this paper are Reillopleura braddocki gen. etsp. nov. and Notoaphelaspis horizontalis sp. nov. Faunalaffinities are mainly with the Ellsworth Mountains (WestAntarctica), western Queensland, and China.Keywords Cambrian; trilobites; Bowers Terrane; MolarFormation; Spurs Formation; Reil ly Ridge; HoulistonGlacier; lateral facies change; Reillopleura braddocki gen.et sp. nov.; Notoaphelaspis horizontalis sp. nov.; newbiostratigraphic names

INTRODUCTIONThe trilobites described here come from two areas withinthe fault-bounded strip of Cambrian sediments and volcanicsknown as the Bowers Terrane (Laird & Bradshaw 1983) ofNorthern Victoria Land, Antarctica. From the first area,Houliston Glacier (Fig. 1), trilobites provide the only agedata on Bowers Supergroup rocks between the SledgersGlacier area and the Mariner Glacier area, 200 km to thesoutheast.From the second area, Reilly Ridge, trilobites from

G95042Received 2 June 1995; accepted 20 February 1996

several localities have previously been reported,(Cooper etal. 1976, 1982; Mortimer et al. 1984; Cooper & Shergold1991), but only those from a single locality (RS/f584: localitynumbering is explained below), of early Late Cambrian age,have so far been described (Schmidt-Th ome & Wolfart 1984;Cooper et al. 1990). The inarticulate brachiopod, Stilpnotretacf. magna Henderson and MacKinnon, of similar age, wasfigured by Rowell et al. (1983) from locality RS/f456(Fig. 1).We describe faunas ranging from late Middle Cam brian

to middle Late Cambrian from 13 localities at Reilly Ridgeand two at Houliston Glacier. They are in rocks mapped asSpurs and Molar Formations and comprise conglomerate,sandstone, and mudstone. Two of the collections are fromallochthonous limestone blocks and therefore provide onlyminimum ages for the enclosing sediments. From otherallochthonous block s (olistoliths), in the southern and cen tralparts of Reilly Ridge, trilobites of older Middle Cambrian(Undillan or Floran) age have been recovered (Cooper &Shergold 1991; Cooper & Jago unpubl.) but are not describedhere. Of the 54 taxa described here, 16 are recorded for thefirst time from the Antarctic continent. The stages and zonesused are those of Northern Australia (Shergold et al. 1990;Shergold 1993) (Table 1).Bowers Terrane is bordered to the southwest by ametamorphic/ igneous complex (Wilson Group, in theLanterman Terrane) and to the northeast by a meta-sedimentary flysch unit (Robertson Bay Group, making upthe Robertson Bay Terrane) . Considerable horizontal"displacement of the three crustal blocks has been inferredalthough views differ as to the direction and amount ofrelative movement on the intervening faults (Bradshaw etal . 1985a, b; Bradshaw 1987; Findlay 1987; Gibson 1987).Reilly Ridge lies near the southwest bounding fault of theBowers Terrane (Lanterman Fault) in a structurally complexzone (Bradshaw et al. 1982; Cooper et al. 1990).The fossils described here were collected by the New

Zealand NZARP Antarctic Expeditions of 1974/5, 1981/2,and the combined NZARP and GANOVEX (German)Expedition of 1984/5. Fossil localities are numbered by theirNew Zealand Fossil Record File number (e.g., RS/f402);collections are prefixed with GS. Registered specimens areheld by the New Zealand Geological Survey (now Instituteof Geological & Nuclear Sciences) and are prefixed AR.The fossil localities and the age of their trilobite asse mblagesare discussed in Appendix 1. The locality distribution oftrilobite taxa is shown in Table 2. Trilobite taxonomy hereinis the responsibility of Jago and Cooper.Structure at Reilly RidgeThe structure and stratigraphy of Bowers Supergroup rocksat Reilly Ridge is outlined by Cooper et al. (1990). Thestratigraphic extent of rocks mapped as Spurs Formation w asextended from previous interpretations (Laird & Bradshaw


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364 New Zealand Journal of Geology and Geophysics, 1996, Vol. 39\ 163 13' E . \_ . 163* 15 E 163 17'E

^ " ^ Z ^ "-.. " - * . ^ . ^ f f i e " C o n t a c tL "mm *'-^mm " " * ^ - " ^ * > ' ^ - i ' ^ ^ ~ w Unconformity

Basic sills an ddikes

Leap Year Gp(Camp Ridgel t i t )

FaultsStrike, dip and facingNZ fossil record localityContour (m)

~ ' Limit of ice'r&^cv ; x

180 \ ^

168E\ \ '\ \Carryer Glacier _ J _ \^ \Reilly Ridge * s Robertson* a \ Bay terraneHouliston Glacier 5*\(512,385) \ x\ \Wlson \ , \terrane

Mariner Glacier

\ \

Southern end ofReilly Ridge (Fig.4;

\ - : " - - . . . \ > N v


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Cooper et al.Cambrian trilobites, N Victoria Land 36 5Table 1 Late Middle and Late Cambrian stages and zones ofnorthern Australia (Shergold et al. 1990; Shergold 1993). TheMiddle Cambrian Late Cambrian bo undary is placed within theAcmarhachis quasivespa Zone (after Daily & Jago 1975).

Fault Slice1 Fault Slice2 Fault S lice3

Late CambrianDatsonian (part)Payntonian

Iverian

[damean

vlindyallan(part)

Cordylodus proavus (part)Mictosaukia perplexaNeoagnostus quasibilobus/ShergoldianomasSinosaukia impagesRhaptagnostus clarki maximus/R. papilioRhaptagnostus bifax/NeoagnostusdenticulatusRhaptagnostus clarki patulus/CaznaiasectatrixRhaptagnostus clarki patulus/CaznaiasquamosaHapsidocare lilyensisPeichiasha nia tertia/P . quartaPeichiashania secunda/Prochuangiaglabella

Wentsuia iota/Rhaptagnostus apsisIrvingella tropicaStigmatoa dilomaErixanium sentumProceratoyge crypticaGlyptagnostus reticulatusGlyptagnostus stolidotusAcmarhachis quasivespa (part)Middle CambrianMindyallan(part)3oomerangianLndillan

Acmarhachis quasivespa (part)Erediaspis eretesDamesella torosa/Ascionepea janitrixLejopyge laevigataGoniagnostus nathorstiDoryagnostus notalibraePtychagnostus punctuosus

:-;| Alternating line sandston e& siltstone, channel sands

- 5 8 6Conglomerate an dcoarse grained sandstoneFossiiiferous h orizonRegional unconformityFault

r 100m- 80- 60- 40- 20- 0 - * f

y-n. -4--------L-~-~-~o > -_ -_

405

567564

Fig. 2 Sketch columns for the stratigraphic sequences in FaultSlices 1, 2, and 3. Time-stratigraphic correlations are shown bysolid lines, lithostratigraphic correlations shown by dashed lines.Except for strata shown as Leap Year Group in Fault Slice 3, ailrocks represent Spurs Formation of the Mariner Group. The horizonwith fossils described by Cooper et al. (1990) is indicated by anasterisk.

1983) to include rocks which contain all of the fossillocalities at Reilly Ridge described herein. South EndConglomerate was established as a member within MarinerFormation by Cooper et al. (1990).Reilly Ridge lies within a structurally complex zonealong the southwestern margin of the Bowers Terrane(Bradshaw 1987). The rocks discussed here are steeplydipping, are folded on both a regional and intraformationalscale, and are transected by several subparallel faults whichbound elongated belts or slices. We demonstrate that thestratigraphic sequences show pronounced facies changesfrom o ne slice to the next, suggesting significant displace-ment on the bounding faults. This paper deals with fossilsfrom three of the fault-bounded slices, herein called FaultSlices 1,2, and 3 (Fig. 1,2).Stratigraphic implications of new fossilsThe regiona l s t ra t igraphic re la t ionships for BowersSupergroup units between Carryer Glacier and MarinerGlacier are illustrated in Fig. 3. Marked lateral faciesvariations and time-transgressive boundaries from bothsoutheast to northwest (along the belt) and southwest tonortheast across the belt are apparent.Molar Formation: At Houliston Glacier, 65 km southeastof Reilly Ridge, trilobites of Mindyallan age, includingGlyptagnostus stolidotus, have been found in the youngest

exposed beds of Molar Formation (Sledgers Group) andrepresent the only in situ fossils know n from the formation.Nine kilometres to the northwest, at Neall Massif, lateMiddle Cambrian trilobites have been recovered fromlimestone blocks in a debris flow conglomerate within MolarFormation, providing the only other fossils known from theformation and a minimum age for it at this locality. SpursFormation, which regionally overlies Molar Formation, isnot exposed at Houliston Glacier.The Mindya l lan age of Mola r Format ion beds a tHouliston G lacier contrasts with the Boom erangian or olderage for the overlying Spurs Formation at Reilly Ridge,Carryer Glacier, Mount Glasgow, and Mariner Glacier(Cooper et al. 1983; herein), implying a diachronous contactbetween the two formations. Regionally, the stratigraphictransition from Molar to Spurs Formations is gradational(Laird & Bradshaw 1983) and is marked by the dis-appearance of turbidite sand stone, which is abundant in theMolar, and volcaniclastic detritus, which is locally abundant.Limestone-bearing debris flow conglomerates, rare in MolarFormation, are common in Spurs Formation. The time-transgressive nature of the contact indicates lateral facieschanges and that turbidite deposition persisted longer atHouliston Glacier than elsewhere. Age range of MolarFormation is from Boomerangian (or older) to Mindyallan.Spurs Formation: The oldest age-diagnost ic fossi ls


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Table 2 Locality distribution of trilobite taxa described in this paper. Locality numbers marked with an asterisk (*) are from allochtho nous blocks.Middle Cambrian

BoomerangianLate Cambrian

Mindyallan IdameanCollection number (GS)Locality number (RS) 12241402* 12241A674 13285512* 13894567 12228585 1324845 9 13903576 13912585 13913586 13911584 1390557 8 13908581 13244455 13900573 13893566 13915588

Idolagnostus dryasPtychagnostus aculeatusAspidagnostus inquilinusAspidagnostus sp .Ptychagnostus cf. cassisAgnostardis sp .Lejopyge armataLejopyge sp .Lejopyge calvaKormagnostella sp.Megagnostusl sp .Pseudagnostus cf. idalisGlyptagnostus stolidotusGlyptagnostus reticulatusAmmagnostus sp.Oxyagnostus sp .Onchopeltis sp.Reillopleura braddocki sp. nov.Prochuangia sp .Aphelaspis sp .Notoaphelaspis horizontalis sp. nov.Asaphiscidae sp.Fuchouia sp. indet.Dolichometopidae gen. et sp. indet.Ngnanasanellal sp.Menocephalitesl sp .Levisial sp .Solenopleuridae gen. et. sp. indet.Meteoraspis cf. bidensMeteoraspisl sp .Sudanamocarinal sp . indet.Catillicephalidae gen. et sp. indet.Changshanocephalusl suspicorNotoaphelaspis sp .Pagodia sp .Rhyssometopus sp .Bergeronites cf. dissidensBergeronites sp .Doremataspis sp .Liostracina cf. nolensLiostracina sp .Ptychoparidae unassignedcranidium 1cranidium 2

Nm

gooo

oft

o


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Cooper et al.Cam brian trilobites, N Victoria Land 367

XX X

x x x x x x x x x x x x

1"3a sI;> a .

111 E E3 31212335'2 E S E'2 S 2 2 . .J O CJ O O .f.lo ^S E22 3 C5 8)

5

>oe

& ^ 'fV ^ 'O&-S ^ ^ - s l . . S . g '

aco, D.S

a ~a .y 5r Sr c 5 r ^ QSr> 'r* C\ cv [i M n ^ u6 ..S 1 o^ loQCj i II

described here are from the lowest exposed beds of SpursFormation at the southern end of Reilly Ridge (Fault Slice 3,Fig . 4 ) . The agnosto id t r i lob i tes , Lejopyge sp. andPtychagnostus aculeatus, have been found in concretionsin dark shales at the southern end of Reilly Ridge (RS/f567),indicating a Boomerangian age. Embedded in the shale afew metres stratigraphically below this horizon is a large,30 m thick, olistolithic lens of limestone conglomerate (RS/f402). Trilobites, including Lejopyge calva, have been foundin the lens and are of late Middle Cambrian (probablyBoomerangian) age, suggesting the presence of an adjacentcarbonate shelf of which no other remains are preserved. Inthis region, Spurs Formation is unconformably overlain byunfossiliferous conglomerate and sandstone (Leap YearGroup). From just below the unconformity, in beds mappedas Sou th End Conglomera te Member (RS/f566) , aMindyallan (G. stolidotus Zone) assemblage has been found,indicating that post-Mindyallan beds of the formation havebeen excluded by the unconformity, as at Carryer Glacier,30 km to the north (Cooper et al. 1983).From 6 km to the north, ho wev er, in Fault Slice 1,limestone and calcareous sandstone and siltstone of SpursFormation contain trilobite assemblages at six localities andrange in age from Mindyallan to at least late Idamean(Fig. 2). The age of beds truncated by the unconformity atReilly Ridge thus ranges from late Mindyallan in FaultSlice 3 to late Idamean (or younger) in Fault Slice 1. Theminimum age range of Spurs Formation at P.eilly Ridge isBoomerangianIdamean.In Fault Slice 2, trilobite assemblages representing theG. stolidotus Zone (RS/f586, 588), have been found in alimestone, sandstone, shale sequence (Spurs Formation) and,2.5 km along-strike, in a sandstone-conglomerate sequence

mapped as the South End Conglomerate Member of SpursFormation (RS/T576; Fig. 1). No intervening fault has beenmapped, and abrupt lateral facies change is implied.At Marine r Glacier, 150 km to the south east, theformation ranges from late Midd le Cam brian to early Iverianin age (Cooper & Shergold 1991). A southeast-northwestincrease in age of the youngest beds of Spurs Formation,along the axis of the belt of Bowers Supergroup rocks, hasbeen inferred by Cooper et al. (1982, 1983) and Laird &Bradshaw (1983). The new trilobite localities suggest, inaddition, marked local increases in age along and across thebelt (Fig. 3), suggesting tectonism during the intervalbetween deposition of the Mariner and Leap Year Groups(i.e. in Idamean or IverianPayntonian time).Limestone, equivalent in age to the upper SpursFormation at Mariner Glacier, was forming in the vicinityof Reilly Ridge, as evidenced by the massive, locally derived,olistolithic blocks and debris conglomerates w ith trilobites,in shales and turbidites of Spurs Formation. O lder carbonateswere also being eroded. There is no remaining record ofthese shelf carbonates in Northern Victoria Land.

Faunal affinitiesThe faunas described herein have closest affinities with thoseof western Q ueensland described by Opik (1961a, b , 1963,1967, 1979), Shergold (1975, 1980, 1982), Henderson(1976), and Jell & Robison (1978), with the following generabeing common to both areas: Meteoraspis, Sudanamocarina,Fuchouia, Changshanocephalus, Pagodia, Rhyssometopus,Bergeronites, Liostracina, and Doremataspis.


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368 New Zealand Journal of Geology and Geophysics, 1996, Vol. 39

* age diagnostic fossilsFig. 3 Diagram matic representation of stratigraphic relationships in the Bowers Terrane, between Carryer Glacier and Mariner Gla cier

REILLY RIDGE - Southwest spur, sketch profileWEST

LEGEND Dip" Younging direction

i 405 Fossil record number^ Concretions

% 8 & Limestone blocksN ^\ Sha le

ConglomerateSandstone

Leap EASTYearG r 0 U P , 1700

J 1600

100 200Approximate horizontal scale (m)

300 400

Fig. 4 Sketch of main spur at southern end of Reilly Ridge, showing position of trilobite horizons discussed in this paper.

Notoaphelaspis has been recorded from western New SouthWales (Powell et al. 1982). The presence or suspectedpresence of the following genera indicate affinities w ith thelate Middle to early Late Cambrian faunas of eastern Asia,particularly China: Fuchouia, Menoceph alites, Levisia,

Pagodia, Liostracina, and Bergeronites. Bergeronites is alsofound in Kazakhstan (Ergaliev 1980), Iran (Kushan 1973).Sweden, Siberia, and elsewhere (Wang et al. 1989).Fuchouia, Aphelaspis, Prochuangia, Changshano-cephalus, and Onchopeltis are also known from the Middle


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Cooper et al.C ambrian trilobites, N Victoria Land 36 9to Late Cam brian faunas of the Ellsworth M ountains, WestAntarctica (Jago & Webers 1992; Shergold & W ebers 1992).

SYSTEMATIC DESCRIPTIONSClassification of the agnostoids essentially follows that ofShergold etal. (1990).

Family AGNOSTIDAE M'Coy, 1849Subfamily AMMAGNOSTINAE Opik, 1967Genus Ammagnostus Opik, 1967TYPE SPECIES: Ammagnostuspsammius Opik, 1967, p. 139,pi . 66, fig. 1 ^ ; text fig. 40.REMARKS: The species Ammagnostus duibianensus Lu &Lin (1989 , p. 207) s eems to be little, if any, different fromAmmagnostus psammius as figured by Opik (1967, pi. 66,fig. 1-4), and is probably a synonym.Genus Ammagnostus sp . Fig. 6C, DM A T E R I A L : 2 poorly preserved cephala and 2 poorlypreserved pygidia from locality RS/f585.REMARKS: The features which suggest that this speciesbelongs in Ammagnostus are: (1) a cephalon with anunconstricted acrolobe and narrow border; (2) a pygidiumwith a wide border and a constricted acrolobe; and (3) awide pygidial axis which reaches the posterior border.Because of the poor preservation of the Houliston Glacierspecimens it is difficult to assign them to a previouslydescribed species.Genus Kormagnostella Romanenko, 1967TYPE SPECIES: Kormagnostella glabrata E. Romanenko (inRomanenko, E . V. & R omanenk o, M . F. 1967, p. 25, pi. 1,fig. 22 , 23)DIAGNOSIS: See Shergold et al. (1990, p. 36).Kormagnostella sp. Fig. 8BMATERIAL: 1 cephalon (AR1992) from RS/f573.REMARKS: Th is effaced cep halo n, w ith an effaced ante ro-glabella, an almost straight F3 furrow, and strongly convexDosterior region of the posteroglabella, clearly belongs toKorm agn ostella.

Subfamily GLYPTAGNOSTINAE Opik, 1963Genus Glyptagnostus Whitehouse, 1936TYPE SPECIES: Glyptagnostus toreuma Whitehouse, 1936,a 102, pi. 9, fig. 17-20 (=Glyptagnostus reticulatus Angelin,1851).Glyptagnostus stolidotus Opik, 1961 Fig. 6A -B , FISYNONYMY: See Lu & Lin (1989, p. 86).

MATERIAL: Several cephala and py gidia (AR 1299, A R130 2.AR1303, AR1305, AR1752, AR2000) from localities RS/f585, and RS/G76.REMARKS: The concept of this important and distinctive zonefossil has been discussed at length by Opik (1961a, 1967)and Palmer (1962). Even when the species is poorlypreserved in shale as at locality RS/f585 (Fig. 6A, B) itsdistinctive nature allows it to be identified.Glyptagnostus reticulatus reticulatus (Angelin, 1851)Fig. 6ESYNONYMY: See Pen g (19 92, p. 22 ).REMARKS: One distorted pygidium (AR2013) from localityRS/f578 clearly belongs in this important zonal species.Genus Agnostardis Opik, 1963TYPE SPECIES: Agnostardis amplinatus Opik, 1963, p. 40,pi. 3, fig. 1-8; text-fig. 8, 9.DIAGNOSIS: See Shergold et al. (1990, p. 38).Agnostardis sp . Fig. 6JMATERIAL: 1 well-preserved p artial pygidium (A R2073)from locality RS/f576.DESCRIPTION: Small pygidium with flat border; non-deliquate border furrow. Posterolateral spines appear to beabsent although there is a change in direction of the marginat their expected position. Smooth pleural areas. Fl, F2effaced. Large elongated axial node. Axis outlined by well-developed shallow furrows, tapers evenly to what appearsto be a sharply rounded posterior at about half the length ofthe pygidium. This is the posterior of what Opik (1963,fig. 8) described as the middle axial segmen t. There are veryfaint traces of furrows outlining the anterior part of theposterior bulb of the axis.DISCUSSION: The pygidium alm ost certainly represents a newspecies of Agnostardis , but the authors are reluctant toestablish a new species on the basis of a single incompletepygidium. When compared with the type species, A.amplinatus, the Reilly Ridge specimen is wider, has a less-tapered pygidial axis, a wider flatter border, and a much moreeffaced axial posterior. Most of the specimens of amplinatusfigured by Opik (1963,19 67) have w ell-developed pygidialaxial furrows, as have the specimens of Agnostardis sp .figured by Jago (1986). However, on the pygidia ofamplinatus figured by Opik (1963, pi. 3, fig. 4, and 1967,pi . 67, fig. 7), the axial furrows outlining the posterior bulbof the axis are quite shallow. Indeed, the figured specimensof Opik (1963, 1967) allow considerable intraspecificvariation in A. amplinatus.

Subfamily incertae sedisGenus Idolagnostus Opik, 1967TYPE SPECIES: Idolagnostus agrestis Opik, 1967, p. 104,pi. 59, fig. 9.10; pi. 60, fig. 1, 2; pi. 63, fig. 10; text-fig. 25,26 .


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370 New Zealand Journal of Geology and Geo physics, 1996, Vol. 39Idolagnostus dryas Opik, 1967 Fig. 6ZIdolagnostus dryas Opik, 1967, p. 106, pi. 60, fig. 3- 5; text-fig. 25 .MATERIAL: 1 well-preserved cephalon and anterior thoracicsegment (AR1300, possibly a complete enrolled specimen)is available from locality RS/f588.REMARKS: The s pecimen closely resem bles the three cephalafigured by Opik (1967, pi. 60, fig. 3-5) as /. dryas but isslightly less rectangular and has a slightly narrower border.These differences are regarded as intraspecific.

Family PTYCHAGNOSTIDAE Kobayashi, 1939Subfamily PTYCHAGNOSTINAE Kobayashi, 1939Genus Ptychagnostus Jaekel, 1909TYPE SPECIES: Agnostus punctuosus Angelin, 1851, p. 8,pi . 6, fig. 11.Ptychagnostus aculeatus (Angelin, 1851) Fig. 5NAgnostus aculeatus Angelin, 1851, p. 8, pi. 6, fig. 12.MATERIAL: Incomplete cephalon (AR1304) locality RS/f567.REMARKS: The cephalon shows the radial scrobiculae andmoderately developed granulation typical of P. aculeatus(Angelin).Ptychagnostus cf. cassis Opik, 1961 sp. Fig. 5L, MPtychagnostus cassis Opik, 1961b, p. 77, pi . 20, fig. 4a-13,text-fig. 27.MATERIAL: 1 well-preserved cephalon (AR2107) and apartial pygidium (AR1301) from RS/f567.DESCRIPTION: Cephalon with narrow shallow border furrow;narrow border. Glabella has a length about 0.8 of cephalon.Shallow axial furrow. Glabella tapers forwards quitemarkedly. Fl, F2 effaced. F3 slightly convex to anterior.Anteroglabella has a length about 0.4 that of glabella. Nodistinct axial node. Well-developed preglabellar medianfurrow. Small double basal lobes. Pygidium has a shallowfurrow and a wide flat border. Posterolateral spines absent.Details of pygidial axis not preserved, although there is awell-developed postaxial median furrow. Smooth pleuralareas.REMARKS: The two specimens are placed together tentatively.The combination of a forward tapering glabella, a well-developed preglabellar median furrow, F3 anteriorly convex,double basal lobes, narrow cephalic border, a non-spinosepygidium with a wide flat border, and a postaxial medianfurrow in the pygidium indicates that this species is close toPtychagnostus cassis Opik, 1961. The cephalon describedhere is indistinguishable from those of P. cassis figured byOpik (1961b, pi. 20, fig. 48). However, the pygidial axisof P. cassis as figured by Opik (1961b, pi. 20, fig. 9-12) isslightly more expanded than the specimen figured herein

(Fig. 5M) and hence the spe cies can not be referred definitelyto P. cassis.Genus Lejopyge Hawle and Corda, 1847TYPE SPECIES: Battus laevigatus Dalman, 1828, pp . 136-137REMARKS: Lejopyge has been discussed in some detail byDaily & Jago (1975), Opik (1979), Robison (1984, 1988.1994), and Laurie (1989).The concept of Lejopyge used here is that of Laurie(1989), although, as noted by Daily & Jago (1975) andRobison (1984), L. cos Opik, 1979 is better placed in Larmata rather than L. laevigata as is suggested by Laurie(1989).Lu & Lin (1983, pi. 1 fig. 9-10) erected Lejopygesinensis, which they did not describe until 1989 (Lu & Lin1989, p. 103, pi. 10, fig. 7-12). None of the figuredspecimens are particularly well preserved, but, as noted byLu & Lin, they appear to lack m arginal pygidial spines . Thespecimens figured by Lu & Lin as L. sinensis do not appearto be significantly different from L. laevigata and hence Lsinensis is a probable synonym of L. laevigata.Lejopyge armata (Linnarsson, 1869) Fig. 5J, KSYNONYMY: See Laurie (1989, p. 188) (see also remark*above on Lejopyge cos). To this should be added Lu & Lin(1989, p. 220, pi. 10, fig. 1-6).MATERIAL: 1 cephalon (AR1321) and 1 pygidium (AR1318)from locality RS/f674.REMARKS: The concept of Lejopyge armata has recently beendiscussed by Robison (1984) and Laurie (1989). Thecephalon figured here (Fig. 5J) is a little more effaced thanthose of armata i l lustrated by Laurie (1989, f ig . 7) .Substantial spine bases are seen on the pygidium (Fig. 5K),which suggests that the spines would have been quite long.The spine bases are placed further forwards than in mostpreviously illustrated specim ens of armata, including thosefigured by L aurie (1989, fig. 7), although they are in a similarposition to those on the pygidium illustrated by Westergard(1946, pi. 13, fig. 36).

'Lejopyge calva Robison, 1964SYNONYMY: See Laurie (1989, p. 189).

Fig. 5H, 1

MATERIAL: 1 pygidium (AR12241) from locality RS/f402.REMARKS: This py gidium corresp onds quite w ell to thepygidia figured by Opik (1979, pi. 66, fig. 5-7) as L.praecox, which has since been placed by Laurie (1989,p. 189) in synonymy with L. calva. Robison (1994, p. 53)placed L. praecox in synonymy with Pseudophalacromadubium (Whitehouse, 1936). The faintly outlined pygidialaxis of the specimen figured by Opik (1979, pi. 66, fig. 6)as L. praecox appears to us to indicate affiliation withLejopyge rather than Pseudophalocroma, and hence wesupport the view of Laurie (1989).Lejopyge sp. Fig. 5FMATERIAL: A partial pygidium (AR2079) from RS/T567


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Cooper et al.Cambrian trilobites, N Victoria Land 371

Fig. 5 A-D , P Fuchouia sp. indet.: A, cranidium, AR2010, x2; B, partial cranidium, AR2009, x2; C, pygidium, AR2011, x3; D,partial librigena, AR 2012 , x3 ; P, hypostom e, AR 2005 , xlO . E, Sudanomocarina sp.? cranidium, AR2022, x3. F, Lejopyge sp.,partial pygidium, internal mould, AR2 079, x8 . G, Catillicephalidae gen. et sp. indet., partial cranidium, AR2 008, x20. H, I Lejopygecalva Robison: H, partial cephalon, internal mould AR200 6, xlO ; I, pygidium, AR202 0, xlO . J, K Lejopyge armata (Linnarsson): J,cephalon, AR 1321, xl 5 ; K, pygidium , AR 1318, tectonically distorted, x8 . L, M Ptychagnostus sp.: L, cephalon, internal mould,'AR2107, x 10; M, partial pygidium, internal mould, AR 1301, x7. N, Ptychagnostus aculeatus (Angelin), partial cephalon, rubber castof external mould, AR1 304, xlO . O, Megagnostus (?) sp., partial pygidium, rubber cast of external mould, AR2007 , x8 . Q, S, UVganasanella? sp.: Q, incomplete cranidium, internal mould, AR790, x6; S, cranidium, AR791, x4; U, pygidium, AR795, x5. R, TDolichometopidae gen. et sp. indet.: R, immature p artial cranidium, AR793, xl 5; T, pygidium, AR796, x6. V, Levisia{l) sp., cranidium,internal mould, AR7 89, x6. W , X Menocephalites (?) sp.: W, cranidium, internal mould, AR788, x4; X, cranidium, AR787, x4.Specimens come from the following localities: A-E, G-I, O, P (RS/f402); J-K (RS/f674); F, L-N (RS/f567); Q-X (RS/f512).


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372 New Zealand Journal of Geology andGeophysics, 1996, Vol. 39REMARKS: Less than one-h alf of the pyg idium is preserv ed,and identification is provisional. The axis is largely effacedan d its overall appearance suggests that it belongs inLejopyge.

Family DIPLAGNOSTIDAE Whitehouse, 1936Subfamily PSEUDAGNOSTINAE Whitehouse, 1936Genus Pseudagnostus Jaekel, 1909Pseudagnostus (Pseudagnostus) Jaekel, 1909TYPE SPECIES: Agnostus cyclopyge Tullberg, 1880, p. 26,pi. 2, fig. 15a, c.DIAGNOSIS: See Shergold et al. (1990, p. 49).Pseudagnostus (Pseudagnostus) cf. idalis Opik, 1967

Fig. 8Acf. Pseudagnostus idalis Opik, 1967, pi. 62,fig.8,9; pi. 63,fig. 1-3.MATERIAL: 2 poorly preserved pygidia (AR1991, AR1993)from RS/f573.REMARKS: The overall appearance of these pygidia suggestsaffiliation with Pseudagnostus idalis or a related species.Poor preservation prevents a firm assignment.Genus Oxyagnostus Opik, 1967TYPE SPECIES: Oxyagnostus apicula Opik, 1967, p. 160,pi . 63, fig. 5-7; text-fig. 48.DIAGNOSIS: See Shergold et al. (1990, p. 51).Oxyagnostus sp. Fig. 6YMATERIAL: 1 small well-preserved pygidium (AR1973) fromlocality RS/f588.DESCRIPTION: Ac rolo bes unc ons trict ed. Bo rder furrowshallow, moderately wide; almost flat border narrowsanteriorly. Very short posterolateral spines placed justforward of the axial posterior. Smooth pleural areas do not

meet behind axial posterior. Axis extends almost to fulllength of acrolobe; Fl furrows shallow, almost meet in centreof axis; F2 furrows shallow, interrupted by well-developedelongated node which extends the full length of M2 and wellonto theposteroaxis. Posteroaxis expanded, terminating ina sharp posterior projection which contains a small terminalnode. Axis constricted at M 2.DISCUSSION: This pygidium is placed ten ta t ive ly inOxyagnostus because its acrolobes lack constrictionadiagnostic feature of Oxyagnostus according to Opik. Theoverall appearance of the pygidium resembles Oxyagnostusrather than the similar Acmarhachis, which lacks acrolobeconstriction. The pygidium is not thought to be conspecificwith the cephalon described here as Idolagnostus dryas .because it is elongate rather than transversely elliptical asin /. agrestis, the type species of Idolagnostus.

Family CLAVAGNOSTIDAE Howell, 1937Subfamily ASPIDAGNOSTINAE Pokrovskaya, 1960Genus Aspidagnostus Whitehouse, 1936TYPE SPECIES: Aspidagnostusparmatus Whitehouse, 1936.p. 105, pi. 9, fig. 5 only.DIAGNOSIS: See Shergold et al. (1990, p. 52).Aspidagnostus inquilinus Opik, 1967 Fig. 60Aspidagnostus inquilinus Opik, 1967, p. 120, pi . 4 1 , fig. 1 ];pi . 45 , fig. 1; pi. 56, fig. 1-10; text-fig. 31-33.MATERIAL: 1 well-preserved partial pygidium (AR2074)from RS/f576.REMARKS: Alth oug h only a partial pygidium is available, itmatches well with the distinctive Aspidagnostus inquilinusas described and illustrated by Opik (1967).Aspidagnostus sp. Fig.R E M A R K S : The poorly preserved internal mould of anagnosto id cephalon (AR2075) appears to belong inAspidagnostus. It is from RS/f566.

Fig. 6 A, B, FI Glyptagnostus stolidotus Opik: A, poorly preserved cephalon, sagittally shortened, AR200 0, external mould, x 8; B,pygidium and thoracic segments, AR1752, internal mould, x 6; F, cephalon, AR12 99, xlO; G , pygidium AR 1305, x8; H, partial cephalon.AR1303, xl2; I, partial pygidium, external mould, AR1302, x8. C, D Ammagnostus sp.: C, cephalon, internal mould, AR1753.tectonically distorted, x8 ; D, pygidium , internal mould, AR1754, tectonically distorted, x8. E, Glyptagnostus reticulatus reticulatus(Angelin) , pygidium, AR2013, xlO. J, Agnostardis sp., pygidium, AR2073, xlO. K, pygidium indet. 1., AR2002, xlO. L, MSolenopleuridae gen. et sp. indet.: L, partial cranidium, sagittally shortened, AR2 004, x8 ; M, cranidium, sagittally leng thened, AR1 306.x8 ; these two specimens lie at right angles to each other on the one tectonically deformed slab. N, Cranidium indet. 3, AR2001.x3 . O, Aspidagnostus inquilinus Opik, partial pygidium, rubber cast of external mould, AR2074, xlO. P, Doremataspis sp., twocranidia, AR2024 (left), AR1317 (right), xlO. Q, Pygidium indet. 3, AR2003, x7. R, Cranidium indet. 1, AR1207, xlO. S, TRhyssometopus sp.: S, partial cranidium, AR1206, x4; T, pygidium, AR1314, xlO. U, Cranidium indet. 5, AR1972, x6. V, YVLiostracina cf. nolens Opik: V, cranidium, internal m ould, AR2106, x8 ; W, partial cranidium, AR1 315, x 10. X, Asaphiscidae, pygidiuri.gen. et sp. indet., AR1974, x3. Y, Oxyagnostus sp., pygidium, AR1973, xl5 . Z, Idolagnostus dryas Opik, cephalon and anterior-thoracic segment, AR1 300, xlO. ZA , Bergeronites cf. dissidens Opik, 1967, pygidium, AR1205, x5, external mould with some shellmaterial adhering, showing character of doublure. Specimens come from the following localities A-D (RS/f585), E (RS/f578), F-O(RS/f576), R-S , W, ZA (RS/f459), U-Z (RS/f588).


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374 New Zealand Journal of Geology and Geophysics, 1996, Vol. 39Family incertae sedis

Genus Megagnostus Robison, 1994TYPE SPECIES: Agnostus glandiformis Angelin, 1851, p. 5,pi . 6,fig.1.Megagnostus (?) sp. Fig. 5OMATERIAL: An incomplete pygidium (AR2007) from localityRS/f402.REMARKS: This pygidium is questionably assigned toMegagnostus, Thepygidial border is narrower than in thespecies assigned to Megagnostus by Robison (1994).

Family DOLICHOMETOPIDAE Walcott, 1916Genus Fuchouia Resser & Endo in Kobayashi, 1935TYPE SPECIES: Bathyuriscus manchuriensis Walcott, 1911,p. 97, pi. 16,fig.4.REMARKS: T he type specie s, and co ncept of the gen us, havebeen discussed andclarified by Zhang &Jell (1987).Fuchouia sp. indet. Fig. 5A-D , PMATERIAL: 2 cranidia (AR2009, AR2010), 1 pygidium(AR2011), and a hypostome (AR2005) from RS/f402.REMARKS: TheAntarctic specimens have relatively shortpalpebral lobes and a relatively short length to width ratioof the glabella; among dolichometopid genera they mostclosely match species assigned to Fuchouia. The associatedpygidium has the narrow border and strong interpleuralfurrows that mark Fuchouia (Zhang & Jell 1987, p. 67) andis here grouped with the two cranidia. The tw o cranidia differfrom each other in the angle of divergence of their anteriorfacial sutures and may represent two species.Dolichometopidae gen. et. sp indet.REMARKS: One rather effaced pygidium (AR796, Fig. 5T,loca l i ty RS/f512) is placed ten ta t ive ly in theDolichometopidae. It shows some similarity with pygidiaof Amphoton deois figured in Zhang &Jell (1987, pi. 18,fig. 5-6; pi. 19,fig.4).

The cranidium of Fig. 5R (AR793, locality RS/f512) isalso included here. The specimen is very small and representsan early holaspid stage of development, and is here onhtentatively included within the Dolichometopidae.

Family ELVINIIDAE Kobayashi, 1935Shergold (1980) erected the subfamily Wuhuiinae toaccommodate Australo-Asiatic Dokimocephalidae; heincluded the genera Lorrettina Shergold, 1972, SaimachiuKobayashi, 1937, and Wuhuia Kob ayash i, 1933 in this groupand suggested that Protemnites Whitehouse, 1939 andPrismenaspis Henderson, 1976 may also belong in theWuhuiinae. As part of a revision of the genera Prismenaspisand Protemnites, Shergold (1982) erected a new genusChalfontia based on Prismenaspis aha Henderson, 1976Shergold (1982) placed Protemnites within the Elviniidaebu t did not assign it to a subfamily. Zhang &Jell (1987)placed all the above genera within theWuhuiinae with theexception of Saimachia, which they transposed to theProasaphiscidae. Shergold & W ebers (1992) suggested thatgenera such as Onchopeltis Rasetti, 1944, Olentella Ivshin.1956, Pesaia Walcott &Resser, 1924, Protemnites, andPrismenaspis belong in a new subfamilial taxon related toElviniidae or Dokimocephalinae. The cause of the confusionindicated above is the intergrading morphologies of thevarious genera. It seems to us that, until the whole group isphylogenetically analysed, all the above genera are bestgrouped together. In addition, we would suggest thaispecimens described below as Onchopeltis sp. and thecranidium described by Shergold (1982, pi . 36 ,fig.9) belongin this group, which we have tentatively placed in theElviniidae.Genus Onchopeltis Rasetti, 1944TYPE SPECIES: Oncho peltis spectabilis Rasetti, 1944, p. 250,pi. 39 , fig. 1-5.DIAGNOSIS: See Rasetti (1944, p. 249).

Fig. 5R, T Onchopeltis sp. Fig. 9A, B,E, GMATERIAL: Several cranidia (AR1977, AR1995, AR2034,AR2036) and 1 librigena (AR1983) from RS/f573.DESCRIPTION: Cranidium and l ibr igena covered withscattered granules. Strongly convex glabella has a length

Fig. 7 A, B Bergeronites sp. indet.: A, pygidium, AR1308, obliquely distorted, xl.5; B, partial cranidium, AR1307, x2.5. C, DMeteoraspis cf. bidens Opik: C, partial cranidium, AR2014, obliquely distorted, x2 ; D, pygidium, AR2015, x 12. E, Cranidium indet. 2,AR202 8, x4. F, Cranidium indet. 4, AR1316, xl2 . G,Doremataspis sp., cranidium, AR132 0, sagittally elongated, x8. H, Pygidiumindet. 2, AR1313, tectonically distorted, xlO. I-K , P, Q ,T Pagodia sp.: I, cranidium, AR1210, tectonically d istorted, x5; J, cranidium,AR12 09, tectonically distorted, x5 ; K, partial cranidium, AR2019, sagittally shortened, x6 ; P, pygidium, rubber cast of external m ould,AR2021, tectonically distorted, x8; Q, partial cranidium, AR201 8, tectonically distorted, x9 ; T, partial cranidium, AR 2016, sagitta lyshortened, x6. L, M, O Changshanocephalusl suspicor Shergold & Webers: L, cranidium, rubber cast of external mould, AR1310,x4 ; M, cranidium, internal mould, AR1323, x5; O, librigena, AR1 312, x3. N, Notoaphelaspis sp. cranidium, rubber cast of externalmould, AR1208 , x4. R, Cranidium indet. 6, tectonically distorted, AR2076, x4. S, Librigena indet. l,A R2 01 7,x 2. U,Aspidagnosmssp., cephalon, internal mould, AR2075, xlO. V, Liostracina sp., partial cranidium, sagittally elongated, AR2105, x8. W, Meteoraspi.s?sp., partial pygidium, AR2079, x8. Specimens come from the following localities: A-E (RS/f585); F-G (RS/f586); H-J, L-O (RS/f455); K, P, Q, S, T (RS/f581); R, U-W (RS/f566).


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376 New Zealand Journal of Geology and Geophysics, 1996, Vol. 39(including occipital ring) about 0.75 that of cranidium.Glabella tapers to bluntly rounded anterior. Axial andpreglabellar furrows deeply impressed. Anterior borderfurrow narrow in front of glabellar anterior, widening anddeepening abaxially. Strongly convex elevated border. Deepwide occipital furrow, o ccipital node absent. Lateral glabellarfurrows almost effaced. Semi-elliptical palpebral lobesplaced opposite centroanter ior part of glabella, widepalpebral furrow. Very low eye ridges. Preocular sectionsof facial sutures converge slightly to border furrow fromwhere they are markedly convergent; postocular sections offacial suture markedly divergent. Preocular areas offixigenae slope down steeply to anterior border. Palpebralareas of fixigenae almost flat. Wide deep posterior borderfurrow; narrow convex posterior border.

Librigenae moderately convex. Shallow border furrow;wide, almost flat border extends into thin genal spine.DISCUSSION: This material represents a new species ofOnchopeltis quite close to O. variabilis Shergold & Webers,1992, but the available ma terial is inadequate to erect a newspecies. It differs from variabilis in having longer, moreposteriorly placed palpebral lobes, smaller posterolaterallimbs, and a less granulose surface. The longitudinal profileof Onchopeltis sp. is similar to that of O. variabilis figuredby Shergold & Webers (19 92, pi. 4, fig. 6).

Family CREPICEPHALIDAE Kobayashi, 1935Genus Nganasanella Rosova, 1963TYPE SPECIES: Nganasanella nganasanensis Rosova, 1963,p. 10, pi . l , f ig .2 .Nganasanellal sp. Fig. 5Q, S, UMATERIAL: 3 incomplete cranidia (AR790, AR791, AR792)and 1 pygidium (AR795) from locality RS/f512 are includedin this species.REMARKS: The tw o cran idia h ave short palpeb ral lobespositioned in front of the glabellar midpoint and lying veryclose to the glabellar marginal furrows, leaving room foronly very narrow palpebral areas. Their other distinctivefeature is the strongly diverging anterior segments of thefacial s utures. We are unaw are of any described species withwhich they can be matched. The closest similarities appearto be with Nganasanella interminata from theAcrocephalella granulosa and Pedinocephalites minimuszones (equivalent to Mindyallan) of the Siberian Platform,described by Rosova (1964, p. 74, pi. 18, fig. 1-3, 5-11).

Family SOLENOPLEURIDAE Angelin, 1854Genus Reillopleura nov.TYPE SPECIES: Reillopleura braddocki sp. nov.DIAGNOSIS: Small cranidium with strongly granuloseornament. Strongly convex glabella, with broadly roundedanterior, has length about 0.7 that of cranidium. Very short

preglabellar field, lateral glabellar furrows almost effaced;lp furrows directed very strongly to posterior and almostmeet occipital furrow. Occipital node absent. Almost flatpalpebral lobes centrally placed. Very low eye ridges meetdeep axial furrow at front of glabella. Preocular sections offacial sutures almost straight, slope deeply downwards.Postocular sections of facial suture marked ly divergent. Wideposterior border furrows.DISCUSSION: Zhang & Jell (1987) have discussed anddescribed some of the Chinese Solenopleuridae in somedetail. The Australian Solenopleuridae remain essentiallyundescribed. Jago & Webers (1992) placed their genusSohopleura from the middle Middle Cambrian of theEllsworth Mountains in the Solenopleuridae. Zhang & Jell(1987) stated that most of the Chinese genera described inthe i r paper cou ld be g rouped in to a subfamilySolenopariinae, the only unifying features of which are theshape of the glabella, the short preglabellar field, the narrowcheeks, and short palpebral lobes.The new genus Reillopleura has a relatively narrowerglabella and hence relatively wider fixed cheeks than thegenera described by Zhang & Jell and indeed when comparedwith Solenopleuridae from elsewhere, which may bring into quest ion the ass ignment o f the genus to theSolenopleuridae. However, the overall shape of thecranidium, the orientation of the lateral glabellar furrows(as far as can be seen), particularly that of the lp furrows,the short gently curved palpebral lobes, the path of the facialsuture, and the low eye ridges indicate affiliation with theSolenopleuridae. The eye ridges of Reillopleura braddockimeet the axial furrow further forwards than in most other-species of the Solenopleuridae, although the very low eyeridges of Austrosinia chaleon, the type species of AustrosimaZhang & Jell , meet the axial furrows almost at theanterolateral corners of the glabella.Reillopleura braddocki sp. nov. Fig. 80, Q-TMATERIAL: Several cranidia (including the figured specimensAR1987, AR1988, AR1989, AR1990) are available fromlocality RS/f573.HOLOTYPE: Cranidium (AR1987), Fig. 8Q, R, S.DIAGNOSIS: See generic diagnosis.DESCRIPTION: Small cranidium with strongly granulosesurface ornament. Length of strongly convex glabella(including occipital ring) about 0.7 that of cranidium; atmidlength of palpebral lobes glabellar width is about 0.35that of cranidium. Glabella tapers evenly to a broadlyrounded anterior. Deep axial furrows, shallow preglabellarfurrows. Very short (sag.) gently convex preglabellar field.Moderately deep anterior border furrow; strongly convexborder narrows laterally. Moderately deep occipital furrow;occipital ring without a median node. Lateral glabellarfurrows largely effaced; lp furrows shallow, directedmarkedly to the posterior and almost meet occipital furrow;2p furrows very shallow, directed strongly to posterior. S hort(ex sag.), gently curved, almost flat palpebral lobes oppositecentre of glabella. From anterior of palpebral lobes very loweye ridges are directed slightly forwards to meet the axial


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Cooper et al.Cam brian trilobites, N Victoria Land 377

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Yig. 8 A, Pseudagnostus {Pseudagnostus) cf. idalis Opik, pygidium, AR1991, x7. B, Kormagnostella sp., cephalon, internal mould,AR1992, xl 1. C- F , H Notoaphelaspis horizontalis sp. nov.: C, holotype cranidium, AR 1985, sagittally elongated, x4; D, cranidium,AR1998, sagittally shortened, x6; E, partial cranidium, AR2030, sagittally elongated, x 3; F, cranidium, AR2029 , xlO; H, pygidium,AR21O9, x6. G, P Aphelaspis sp.: G, partial cranidium, AR2 025, x3; P, cranidium, AR20 37, x5. I-N , Prochuangia sp.: I, partialcranidium, AR2028, x6 ; J, partial cranidium, AR 2027, x6 ; K, partial cranidium, AR1 997, x5 ; L, librigena, AR1982, x5 ; M, librigena,AR19 76, x5; N, pygidium, AR198 0, X4. O-T Reillopleura braddocki sp. nov.: O, cranidium, AR1990, x8; Q -S, holotype cranidium,AR198 7, all x8, Q normal view, R anterior oblique view, S lateral oblique view; T, cranidium, AR1988, x8. All specimens are fromlocality RS/f573.


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Cooper et al.Cambrian trilobites, N Victoria Land 37 9Family PROASAPHISCIDAE Chang, 1963

Genus Sudanomocarina Jell, 1978TYPE SPECIES: Sudanomocarina changi Jell in Jell andRobison, 1978, pi. 15, pi. 4, fig. 9-16.Sudanomocarina! sp. indet. Fig. 5EMATERIAL: An incomplete cranidium (AR2022), locality RS/f402, Reilly Ridge.REMARKS: The single c ranid ium generally matc hes thegeneric diagnosis given by Jell & Robison (1978) forSudanomocarina, a new name established by Jell & Robisonfor most species formerly assigned to PseudanomocarinaChernysheva after transference of its type species, P. planaChernysheva, to Chondranomocare Poletaeva. The Antarcticspecimen differs from most species assigned to Sudano-mocarina (e.g., by Jell & Robison 1978; Zhang & Jell 1987)in having anterior facial sutures that converge strongly acrossthe border, palpebral lobes that less closely approach theglabella at the rear, and a relatively broad glabella.

Family LEIOSTEGIIDAE Bradley, 1925Genus Pagodia Walcott, 1905TYPE SPECIES: Pagodia lotos Walcott, 1905, p. 64; 1913,pp . 162-163, pi. 15, fig. 12, 12a, 12a'.REMARKS: Opik (1967), Shergold (1975, 1980), and Zhang& Jell (1987) have discussed Pagodia at length. Opik (1967)and Shergold (1975) erected several subgenera, but Zhang& Jell (1987) made no reference to subgenera. As noted byZhang & Jell, muc h larger collections ofPagodia and relatedgenera are required before the classification of these generacan be determined.Pagodia sp . Fig. 7I-K, P, Q, TMATERIAL: 5 cranidia: 3 from R S/f581 and 2 from RS/f455.1 pygidium in RS/f581 is placed tentatively in this species.DESCRIPTION: Allowing for distortion, the cranidium is widerthan is long. Glabella tapers gently forwards to a verybroadly rounded anterior. Glabella extends to, and slightlyintrudes in to, anterior border furrow which is moderatelywell impressed. Anterior border is narrow and gently convex.Deep axial furrows shallow anteriorly. Occipital furrowmoderately well impressed. Lateral glabellar furrowseffaced. Palpebral lobes poorly preserved on availablematerial, but appear to be short and placed opposite centreof glabella. Faint eye ridges meet axial furrows a little tothe posterior of the glabellar anterior. Wide fixigenae.Preocular areas of fixigenae slope steeply down to borderfiirrow. Pa lpebral areas of fixigenae gen tly convex; posteriorareas of f ixigenae slope down to narrow moderatelyimpressed border furrows. Narrow posterior border.

Ornament com prises isolated coarse tubercles on glabellaand fixigenae. In some specimens (e.g., AR1209, AR1210)there is a suggestion that the tubercles occur in rows runningparallel with the axial furrows.The pygidium has shallow axial furrows. The axis,comprising three axial rings plus terminus, extends almost

to the posterior border. 3 pairs of pleural furrows and 3 pairsof interpleural furrows are present. These furrows becomesuccessively shallower to the posterior. Shallow borderfurrow; slightly convex border. There appears to be low butlarge tubercles on the anterior part of the pleural areas.DISCUSSION: The cranidia described above fit in well withPagodia (Pagodia) as diagnosed by Shergold (1975, p. 170).They differ from all previously described species of Pagodia(Pagodia) by the nature of the ornamentation. Pagodia sp .described herein is similar to Pagodia lotus in terms of theshape and extent of its glabella. The pygidial axis of theReilly Ridge form ex tends further to the posterior than doesthat of P. lotus.Genus Prochuangia Kobayashi, 1935TYPE SPECIES: Prochuangia mansuyii Kobayashi, 1935,p. 186, pi. 8, fig. 8; pi. 10, fig. 1-7.DIAGNOSIS: See Shergold (1980, p. 66).DISCUSSION: Shergold (1980) has discussed the genus indetail. Peng (1992) listed the know n species to which sh ouldbe added P. levis levis an d P. levis tenuis as described byWittke(1984).Prochuangia sp . Fig. 8I-N, 9DMATERIAL: 3 partial cranidia (AR997, AR2029, AR2028), 3librigenae (AR1976, AR1978, AR1982), and 1 pygidium(AR1980) are available from RS/f573.REMARKS: The cranidia are similar to those figured byShergold et al. (1976) as Prochuangia sp. aff. P. granulosaLee. Where the shell is preserved, the surface is granulose,but in the exfoliated parts of the specimen there is little signof granulation. The granules on the specimens figured hereinare of similar density to , but seem to be larger than, those ofP. sp. aff. P. granulosa although this may be a function ofpreservation. The pygidia of the various species ofProchuangia are differentiated by the orientation of theirspines and the degree of axial segmentation (Shergold et al.1976). On the only available pygidium (Fig. 8N ), the spinesare poorly preserved, which makes comparison withpreviously described species difficult. The axis is longer thanthat of P. sp. aff. P. granulosa or of P. glabella Shergold,1980, and it is less obviously represented than in P.granulosa. The spines of P. glabella are placed further tothe posterior than those from the Reilly Ridge form; thespines of P. lictispinata are placed much further forwardsthan those of the pygidium figured here. Prochuangia sp .as described by Shergold & Webers (1992) from theEllsworth Moun tains is similar to the Reilly Ridge specimensas far as can be determined, although the EllsworthMountains form is less granulose.

Family RHYSSOMETOPIDAE Opik, 1967Genus Rhyssometopus Opik, 1967TYPE SPECIES: Rhyssometopus (Rhyssometopus) rhysso-metopus Opik, 1967, p. 274, pi. 25, fig. 1-4; pi. 33 , fig. 4;pi . 46, fig. 3, text-fig. 93-95.


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380 New Zealand Journal of Geology and Geophysics, 1996, Vol. 39Rhyssometopus sp. indet. Fig. 6S, TMATERIAL: Incomplete cranidium (AR1206), locality RS/f459. The associated pygidium (AR1314) is tentativelyreferred to the genus.REMARKS: Althou gh incom plete, th e cran idium shows thelong arcuate palpebral lobes in contact with the glabella,the deeply impressed palpebral furrows, and the lateralglabellar bulges, all characteristic of the genus Rhysso-metopus. Incompleteness of the specimen precludes specificcomparison. An associated pygidium differs from Rhysso-metopus pygidia in having a triangular outline, but resemblesthem in having a prominent, hig h, parallel-sided axis whichreaches to the border and has four axial rings, and a distinctnarrow border which is angulate posteriorly.

Family DAMESELLIDAE Kobayashi, 1935Genus Bergeronites Sun in Kuo, 1965TYPE SPECIES: Drepanura ketteleri Monke, 1903, p. 132,pi . 6, fig. \-A.REMARKS: The relationships between the species describedunder Drepanura, Palaeadotes, and Bergeronites have beendiscussed briefly by Zhang & Jell (1987) and Wang et al.(1989). Zhang & Jell (1987) considered three separate generacan be recognised although they noted that there is amorphological gradation between the three genera. Zhang& Jell (1987, pp. 2 20-2 21) gave a list of species which theyconsider belong in Drepanura, Palaeadotes, and Berger-onites. We would prefer to include all such species inBergeronites, because as noted above there is a gradationbetween the three genera and there appear to be no significantdifferences between them.Bergeronites cf. dissidens (Opik, 1967). Fig. 6ZAcf. 1967 Palaeadotes dissidens Opik, 1967, p. 34 1, pi. 50,fig. 3-8; text-fig. 128-129.MATERIAL: Incomplete pygidium (AR1205), from localityRS/f459.REMARKS: Although incomplete, the pygidium matches thatof Opik's species, Palaeadotes dissidens, with its six pairsof spines, five annulations in the axis , depressed border, deepdistal "pits" on the pygidial interpleural grooves, and longslender anterior pyg idial sp ines. It differs slightly in that thespines of the 6th pair are shorter rather than longer than theother minor spines. The more transverse nature of thepygidium may be due to tectonic distortion.The specimen is interesting in clearly showing thedivision of the doublure into inner (adaxial) terraced, andouter (abaxial) unterraced partsrare among trilobites (Opik1967).Bergeronites sp. indet. Fig. 7A, BMATERIAL: Fragmentary cranidium (AR1307), and pygidium(AR1308), from locality RS/f585.

REMARKS: The py gidium (Fig. 7A) is too fragm entary andtectonically distorted to allow close comparison with anyspecies, but it does show the pattern of marginal spines, aswell as the distal "pits" on the interpleural grooves,characteristic of Palaeadotes as originally defined by Opik(1967), and is here listed as Bergeronites sp. The associatedcranidium (Fig. 7B) is even less complete, but shows thetwo pairs of bifurcated glabellar furrows, glabellar outline,and distally impressed occipital groove, characteristic ofBergeronites. The closest specific comparison is probablyB. acuticulatus (Ergaliev 1980) from the Maly Karatau,Kazakhstan.

Family CHANGSHANIIDAE Kobayashi, 1935Genus Changshanocephalus Sun, 1935TYPE SPECIES: Changshanocephalus reedi Sun, 1935, p. 4 1 ,pi . 1, fig. 25.Changshanocephalus? suspicor Shergold & Webers, 1992Fig. 7L, M, OChangshanocephalus'? suspicor Shergold & Webers, 1992,p. 144, pi. 10, fig. 1-10.M A T E R I A L : 3 partial cranidia (AR1310, A R 1 3 1 1 , an dAR1323) and a librigena (AR1312) from locality RS/f455are assigned to this species.DESCRIPTION: Length of gently convex glabella about 0.65-0.7 that of cranidium. Glabella tapers gently forwards. Axialfurrows shallow. Very shallow preglab ellar furrow deflectedposteriorly at centre. Occipital furrow well developed.Lateral glabellar furrows are effaced although the 1 p furrowsare probably represented by faint indentations in glabellarmargins. Long, almo st flat preglabellar field; wide, shallowanterior border furrow; almost flat wide border.Distinct but shallow palpebral furrows; long, well-developed arcuate palpebral lobes placed opposite pos teriorof glabella. Eye ridges almost effaced. Preocular sectionsof facial suture diverge slightly up to border furrow fromwhere they converge. Postocular sections of facial suturediverge markedly; they run parallel with the posterior marginbefore abruptly curving p osteriorly to intersect the posteriormargin.

Preocular areas of fixigenae slope very gently down toborder furrow; palpebral areas of fixigenae small and flat.Surface of fixigenae and preglabellar areas has closelyspaced, very shallow pits; surface of glabella with lowlongitudinal ridges.Gently convex librigena with pattern of low ridge>running parallel with the palpebral margin. Posterior borderfurrow shallowdeepens abaxially. Lateral border furrowwide and deep; it extends some distance along the genalspine. Wide lateral border with terrace lines which extendinto genal spine.DISCUSSION: T he R eilly R idge specim ens are qu ite clos e toChangshanocephalus! suspicor from the EllsworthMountains illustrated by Shergold & Webers (1992, pi. 10,fig. 1-10). The various furrows, except for the palpebralfurrows, in the Reilly Ridge specimen s appear to be deeper


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Cooper et al.Cambrian trilobites, N Victoria Land 381than those in the Ellsworth M ountains specimens. This maywell be a function of the mode of preservation, however, asmay be the apparent posterior deflection of the preglabellarfurrow. In essenc e, there is no significant differencebetween the Rei l ly Ridge and El lswor th Mounta insspecimens.

Family LIOSTRACINIDAE Raymond, 1937Genus Liostracina Monke, 1903TYPE SPECIES: Liostracina krausei Monke, 1903, p. 114,pi. 3, fig. 10-17.REMARKS: The genus is fully discussed by Opik (1967).Zhang & Jell (1987) list only three species: L. krauseiMonke, L. volens Opik, and L. nolens Opik.

outlined by Opik (1967); short glabella, bacculae, rearwardposition of the palpebral lobes, rearward slanting ocularridges, long (sag.) preocular and preglabellar field (the"brim" of Opik) with venulose prosopon, anter ior lydiverging facial sutures, and relatively wide border. Theydiffer from/), ornatus in having a double, rather than single,ocular ridge and an apparent lack of pits in the distal part ofthe preglabellar field, and probably represent a distinctspecies. Because of their incompleteness, the specimens arenot suitable for the erection of a new taxon; they are thereforeleft in open nomenclature.The specimen of Fig. 7G is clearly a related form andprobably represents the sam e species; it has been tectonicallydeformed (lengthened sagittally) and is incomplete.

Family PTEROCEPHALIIDAE Kobayashi, 1935Subfamily APHELASPIDINAE Palmer, 1960Liostracina cf. nolens Opik, 1967 Fig. 6V, W Genus Aphelaspis Resser, 1935cf. 1967 Liostracina nolens Opik, 1967, pp . 355356, p i. 35,fig. 6, 7.MATERIAL: An almost complete cranidium (AR2106) fromlocality RS/f588 and an incomplete cranidium (AR1315)from RS/f588.REMARKS: The specim ens show the prom inent, slantedocular ridges, parallel-sided glabella, bacculae, and anteriormedian furrow characteristic of Liostracina. Although they'natch well with L. nolens Opik, they are insufficiently wellpreserved for definite assignment.Liostracina sp . Fig. 7VMATERIAL: An intern al m ould of a fragm entary cran idiumiAR2105)fromRS/f566.REMARKS: The poo rly pre serv ed c rani dium is figuredbecause it is one of the few recognisable fossils from thestratigraphically important locality, RS/f566. The medianglabellar furrow, the presence of which distinguishesLiostracina from Doremataspis, appears to be genuine ratherihan the product of tectonic distortion.Genus Doremataspis Opik, 1967"YPE SPECIES: Doremataspis ornata Opik, 1967, p. 357,pi. 16, fig. 1-3; pi. 35, fig. 9; pi. 36, fig. 1-6; pi. 45, fig. 1;text-fig. 138, 139.REMARKS: The genus is monotypic and, so far as we areaware, has been recorded previously only from Australia. Itis fully described by O pik (1967).Doremataspis sp . Fig. 6P, 7GMATERIAL: 2 cranidia (AR 1317 , AR 2024) from locality RS /f576 and, tentatively, 1 cranidium (AR1320), locality RS/f586.REMARKS: The tw o cranidia from locality RS/f576 (Fig. 6P)are incomplete but both show the distinctive generic features

TYPE SPECIES: Aphelaspis walcotti Resser, 1938, p. 59,pi . 13, fig. 14.DIAGNOSIS: See Palmer (1965, p. 58).Aphelaspis sp. Fig. 8G, PMATERIAL: 2 partial cranidia (AR2025, AR2037) fromRS/f573.REMARKS: These cranidia show similarities with Aphelaspisspecies such as A. australis Henderson, 1976, A. cantoriJago, 1987, and A granulata Kuo (see Peng 1992, fig. 27G)in having a relatively long glabella, short preglabellar field,and relatively long palpebral lobes. The Reilly Ridgespecimens have a more tapered glabella and shallower axialfurrows than the species named above.Genus Notoaphelaspis Jell, 1982TYPE SPECIES: Notoaphelaspis orthocephalis Jell (in Powelletal. 1982, p. 144, fig. 11, 1-10).DIAGNOSIS: As given by Jell (in Powell et al. 1982, p. 144)with the amendment that the preglabellar field may bedownsloping to subhorizontal rather than simply down-sloping as originally diagnosed.REMARKS: This genus, which was first described from theIdamean of western New South Wales (Powell et al. 1982),has since been recorded from basal Iverian rocks of theMariner Group of Northern Victoria Land (Shergold &Cooper 1985). In addition, the species described by Solovjevet al. (1984) as Aphelaspis (Proaulacopleura) cf. buttsi andAphelaspis {Proaulacopleura) cylindrica should be placedin Notoaphelaspis and are probably synonymous.Notoaphelaspis horizontalis sp. nov. Fig. 8C-F, HMATERIAL: Several cranidia including AR1981, AR1985,AR2 039, AR2030, and AR2032 from locality RS/T573. Apygidium (AR2109) from the same locality is tentativelyassigned to this species.


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38 2 New Zealand Journal of Geology and Geophysics, 1996, Vol. 39

:r "s

!'-- -; i ' 5

^ "

. r

, HFig. 9 A, B, E, G Onchopeltis sp.: A, large cranidium, AR19 77, x4; B , partial cranidium, AR1 995, x6 ; E, partial cranidium, AR2034.x7 ; G, librigena, AR1983, x6. C, hypostoma gen. et sp. indeL, AR19 79, x5 . D, Prochuangia sp., librigena, AR19 78, x5. F, Cranidiuinindet. 7, AR2O33, x3 . H, Py gidium indet. 4, AR1 999, x5. All specimens are from locality RS/f573.

HOLOTYPE: The cranidium (AR1985) figured in Fig. 8C ischosen as holotype.DIAGNOSIS: Species of Notoaphelaspis with gently taperingglabella and very gently sloping preglabellar field.DESCRIPTION: Surface smooth. Subquadrate cranidium withsubrectangular glabella tapers gently to almost straightanterior margin. Length of gently convex glabella (includingoccipital ring) c. 0.650.7 that of cranidium. Axial andpreglabellar furrows shallow. Occipital furrow shallow.Shallow, but distinct lp furrows make an angle of about45 with axial furrow; 2p furrows very shal low; 3pfurrows are faint depressions rather than furrows. Long(sag.) preglabellar field slopes down slightly to shallow,narrow border furrow; narrow convex b order. Very shallowpalpebral furrows. Gently arcuate palpebral lobes extendfrom ap pro xim ately 3p furrows to just posterio r oflp furrows; p alpebr al areas of fixigenae almost fla t.Transversely oriented eye ridges meet axial furrows near3p furrows. Preocular sections of facial suture slightly diver-gent; postocular sections of facial suture markedly divergent.Shallow posterior border furrows; narrow convex border.

Transversely elliptical pygidium has a relatively wideaxis comprising 4 axial rings and a terminus. The axisextends to a shallow border furrow. Border gently convex.Posterior margin of pygidium deflected anteriorly behindaxis. Pleural areas with 3 ribs and 3 pleural furrows.DISCUSSION: The overall shape of the cranidium indicatesthat this species belongs in Notoaphelaspis Jell. N. horizont-

alis differs from N. orthocephalis in that horizontalis hasan almost horizontal preglabellar field as opposed to thesteeply downsloping field of orthocephalis, a feature alsoseen in Notoaphelaspis sp. of Shergold & Cooper (1985,fig. 6R, S, T). The glabella of N. horizontalis is more taperedthan that of orthocephalis. The palpebral lobes of N.horizontalis are less well developed than those of N. sp. ofShergold & Cooper. The specimen described by Shergoldet al. (1976, p. 272) as Aphelaspid sp. 1 is probably aNotoaphelaspis as noted by Shergold & Cooper (1985). Itis quite close to N. horizontalis and may represent the samespecies. The pygidium illustrated here (Fig. 8H) is includedonly tentatively in this species. It differs from that of N.orthocephalis Jell in having four instead of three rings, lessstrongly segmented pleural areas, and a m ore well d evelopedborder. It is possible that the pygidium belongs with thespecies described above as Aphelaspis sp .Notoaphelaspis sp . Fig. 7NMATERIAL: 1 partial cranidium (AR1208) from locality RS/f455.REMARKS: The gen eral sh ape and p rop ortio ns of thiscranidium are similar to those of Notoaphelaspis ortho-cephalis Jell. The glabella of the Reilly Ridge form tapersforward more than that of orthocephalis. The anterior borderof the Reilly Ridge form is narrower than that of thespec imen f igured by Shergold & Cooper (1985) a sNotoaphelaspis sp .


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Cooper et al.Cambrian trilobites, N Victoria Land 383Family CATILLICEPHALIDAE Raymond, 1938

Catillicephalidae gen. et. sp. indet. Fig. 5GMATERIAL: Incomplete cranidium (AR2008), localityRS/f402.REMARKS: Although incomplete, the cranidium shows thehighly inflated, anteriorly expanding glabella, narrowdownsloping fixigenae, parallel or converging anteriorsutures, and narrow but d istinct anterior border characteristicof Catillicephalidae, as discussed by R asetti (1954) and Shaw(1952, 1966). The specimen is closest to the genus ButtsiaWilson, but is too incomplete for definite assignment.

Family ASAPHISCIDAE Raymond, 1924Asaphiscidae, gen. et sp. indet. Fig. 6XMATERIAL: 1 well-preserve d pygidium (AR19 74) fromlocality RS/f588.DESCRIPTION: T ransv ersely elliptical pygid ium ; pleu ral areasalmost entirely effaced except at anterior. Border wide, flat.Axis comprising 6 annulations plus a terminus, extends toposterior border; a low swelling present on border behindaxis.REMARKS: Without the corresponding cephalon or cranidiumit is not possible to place this pygidium in a particular genus ;it could belong in Blountia or a similar genus.Ptychopariidae gen. et sp. indet.Listed below are various exoskeletal fragments that are eithertoo incomplete or too poorly preserved for generic or familialassignment.Cranidium 1: Fig. 6R (AR1207, locality RS/f459)This fragmentary cranidium has broad palpebral lobeswith a sharply defined palpe bral furrow. In general glabellarshape and location of the palpebral lobes it resemblesPlecthfer Opik (1967) and Crepicephalina Resser & Endoas illustrated by Zhang & Jell (1987, e.g., in pi. 35, 36). Theshape, breadth, and sharp definition of the palpebral lobesare similar to those of Rhyssometopus Opik, 1967, fromwhich it differs in its wid er palpebral areas of the fixigenae.Cranidium 2: Fig. 7E (AR2028 , locality RS/f585)This cranidium (Fig. 7E) lies next to that of Bergeronitessp. (Fig. 7B), and has a long narrow, parallel-sided glabellawi th weak ly developed occ ip i ta l fu r row, genera l lyresembling Auritama Opik, 1967.Cranidium 3: Fig. 6N (AR2001, locality RS/f576)This poorly preserved and incomplete cranidium has ageneral resemblance to Pedinocephalus (e.g., see Ivshin1962, fig. 24).Cranidium 4: F ig. 7F (AR1 316, locality RS/T586)This specimen shows the broad, well-defined palpebral lobeand glabellar form of Rhyssometopus Opik. The associated

free check has the raised and "rolled-over" border like thatfigured by Opik (1967, pi. 26, fig. 5) for R. princeps.Cranidium 5: Fig. 6U (AR1972, locality RS/f588)In terms of general morphology, this cranidium resemblesOnchopeltis Rasett i , but more and better preservedspecimens will be needed to affirm the comp arison.Cranidium 6: Fig. 7R (AR2076, locality RS/f566)The incomplete, tectonically distorted specimen has closelyspaced granules on the glabella with less closely spacedgranules on the fixed cheeks. Only the lp furrow is present.It has some resemblance to Onchopeltis but differs in havingnarrower fixed cheeks.Cranidium 7: Fig. 9F (AR2033, locality RS/f573)This poorly preserved cranidium has similarities to bothNotoaphelaspis horizontalis and Aphelaspis sp., both ofwhich occur in the same fauna. However, i ts poorpreservation prevents assignment to generic level.Librigena 1: Fig. 7S (AR2017, locality RS/T581)A well-preserved librigena can not be matched with Pagodiasp., which is the only other species known from this fauna.Pygidium 1: Fig. 6K (AR2001, locality RS/f576)This pygidium can not be matched definitely with any ofthe cranidia from the locality.Pygidium 2: Fig. 7H (AR 1313, locality RS/T455)This small pygidium has an axis which stops well short ofthe posterior border. The axis comprises four axial rings plusa terminus. Both pleural and interpleural furrows are presentwith the pleural furrows reaching almost to the pygidialmargin.Pygidium 3: Fig. 6Q (AR200 3, locality RS/f576)Incomplete and poorly preserved, this specimen has thegeneral morphology of Blountia.Pygidium 4: Fig. 9H (AR1999, locality RS/f573)This incomplete pygidium can not be assigned with certaintyto any of the species described from this locality. It has anaxis which extends almost to the posterior border; the axiscomprises four very well marked axial rings plus a terminus.There appear to be two broad pleural furrows.Hypostoma, gen. et sp. indet.: Fig. 9COne well-preserved elongated quite convex hypostome(AR1979) comes from locality RS/T573. It may belong inthe species described herein as Aphelaspis sp .

ACKNOWLEDGMENTSThese fossils were collected during expeditions of the New ZealandAntarctic Research Programme in 1974/75 and 1981/82 by Cooperand Jago and during the joint NZARP/GANOVEX Expedition of1984/85 by Begg. Logistic support was supplied by NZARP,ANARE, GANOVEX, and the VXE-6 squadron. RAC and JGB


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384 New Zealand Journal of Geology and Geophysics, 1996, Vol. 39were supported by the ( then) New Zealand Department ofScientific and Industrial Research and New Zealand Foundationfor Research, Science and Technology. Fieldwork and subsequentlaboratory work by JBJ has been supported by the AustralianResearch Council, the Australian Antarctic Science AdvisoryCom mittee, and the University of South Australia. The fossils werecollected with the assistance of John Bradshaw, Peter Braddock,Bert Rowell, and David McKinnon. Dawn Leonard (GartrellSchool) typed the f inal manuscript; Wendy St George gaveassistance with the photography. Th is paper was improved by theconstructive comments of two referees, A. R. Palmer (Colorado)and J. R. Laurie (Australian Geological Survey Organisation,Canberra).

REFERENCESAngelin, N. P. 1851: Palaeontologica Suecica, Pars 1. Iconographiacrustaceorum formationis transitionis. Fasc. 1, 1-24, pi.1-19.Bradshaw, J. D. 1987: Terrane boundaries and terrane d isplacementin northern Victoria Land , Antarctica: some problems andconstraints. In: Leitch, E. C ; Scheibner, E. ed . Terraneaccretion and orogenic belts. American Geophysical Uniongeodynamic series 19: 199206.Bradshaw, J. D.; Laird, M. G.; Wodzicki, A. 1982: Structural styleand tectonic history in Northern Victoria Land. In:Cr addock , C . ed . Anta r c t i c geosc ience . Madison ,University of Wisconsin Press. Pp. 809816.Bradshaw, J. D.; Begg, J. G.; Buggisch, W.; Brodie, C ; Tessensohn,F. ; Wright , T . O. 1985a: New data on Palaeozoicstratigraphy and structure in North Victoria Land. Ne wZealand antarctic record 6 (3): 16.Bradshaw, J. D.; Weaver, S. D.; Laird, M. G. 1985b: Suspectterrenes and Cambrian tectonics in Northern Victoria Land,Antarctica. In: Howell, D. G. ed . Tectonostratigraphicterranes of the Pacific region. Circum-Pacific Council forEnergy and Mineral Resources earth science series 1:467-479.Cooper, R. A.; Shergold, J. H. 1 991: Palaeozoic invertebrates ofAntarctica. In: Tingey, R. E. ed . Geology of Antarctica.Oxford, Oxford University Press. Pp. 45 5^ 86 .Cooper, R. A.; Jago, J . B.; Mackinnon, D. I . ; Simes, J . E.;Braddock, P. 1976: Cambrian fossils from the BowersGroup, Northern Victoria Land, Antarctica (preliminarynote). New Zealand ournal ofgeology an d geophysics 19:283-288.Cooper, R. A.; Jago, J. B.; MacK innon, D.; Shergold, J. H.; Vidal,G. 1982: Late Precambrian and Cambrian fossils fromNorthern Victoria Land and their stratigraphic implications.In: Craddock, C. ed . Antarctic geoscience. Madison,University of Wisconsin Press. Pp. 629-633.Cooper, R. A.; Jago, J. B.; Rowell, A. J. 1983: Age and correlationof the Cambrian-Ordovician Bo wers Supergroup, NorthernVictoria Land. In: Oliver, R. L.; James, P. R.; Jago, J. B.ed . Antarctic earth science. Canb erra, Australia, Academyof Science. Pp. 128-131.Cooper, R. A.; Begg, J. G.; Bradshaw, J. D. 1990: Cambriantrilobites from Reilly Ridge, northern Victoria Land,Antarctica and their stratigraphic implications. NewZealand journal of geology and geophysics 33: 55-66.Daily, B. ; Jago, J. B. 1975: The trilobite Lejopyge Hawle and Cordaand the middle-upper Cambrian boundary. Palaeontology18 : 527-550.Dalman, J. W. 1828: Arseberattelse om nyare zoologiska arbetenoch upptacke r . S venska Ve tensk apsacade m ien ,Arsberattelser, Stockholm. 138 p.

Ergaliev, G. K. 1980: The Middle and Upper Cambrian trilobitesof the Maly Karatau. Akadem iya Nauk Kazakhstana SSR,Alma-Ata. 211 p., 20 pi. [In R ussian.]Findlay, R. H. 1987: A review of the problems important forinterpretation of the Cambro-Ordovician paleogeographyof northern V ictoria Land (Antarctica), Tasmania and N ew

Zealand. In: McK enzie, G. R. ed . Gondw ana Six. Structuretectonics and geophysics. Geophysical monograph 40:49-66.Gibson, G. M. 1987: Metamorphism and deformation in theBowers Supergroup; implications for terrane accretion innorthern Victoria Land. In: Leitch, E. C ; Scheibner, E.ed : Terrane accret ion and orogenic bel ts . AmericanGeophysical Union geodynamics series 19: 207219.Harrington, H. J. and others 1959: Arthropoda. In: Moore, R. C.ed . Treatise on invertebrate paleontology. Lawrence.Kansas. Geological Society of America and U niversity ofKansas.Henderson, R. A. 1976: Upper Cambrian (Idamean) trilobites fromwestern Queen sland, Australia. Palaeontology 19: 325-364.Ivshin, N. K. 1962: Upper Cambrian trilobites of Kazakhstan, 2.Kazakhstan SSR Academy of Science. Transactions of theInstitute of Geological Sciences. Pp . 1412.Jago, J. B. 1986: An early Late Cam brian fauna from Tom Creek,western Tasmania. Papers and proceedings of the RoyalSociety of Tasmania 120: 97- 98 .Jago, J. B.; Webers, G. F. 1992: Middle Cambrian trilobites fromthe Ellsworth Mountains, West Antarctica. GeologicalSociety of America memoir 17 0: 101124.Jell, P. A.; Robison, R. A. 1978: Revision of a late Middle Cambriantrilobite faunule from northwestern Queensland. Universityof Kansas paleontological contributions paper 90.Kobayashi, T. 1935: The Cambro-Ordovician formations and

faunas of South Chosen. Palaeontology, Part 3 . Cambrianfaunas of South Chosen with a special study on theCambrian trilobite genera and formations. Journal of theFaculty of Science, Imperial University of Tokyo ser. 2 (4):49- 344 .Kushan, B. 1973: S tra t igraphie und tr i lobi tenfauna in derMila-Formation (Mittelkambrium-Tremadoc) in Alborz-gebirge (N-Iran). Palaeontographica A 144: 113165.Laird, M. G.; Bradshaw, J. D. 1983: New data on the LowerPalaeozoic Bowers Supergroup, Northern Victoria Land.In: Oliver, R. L.; James, P. R.; Jago, J. B. ed . Antarcticearth science. Canberra, Australian Academy of Science.Pp . 123-126.Laurie, J. R. 1989: Revision of species of Goniagnostus Howelland Lejopyge Corda from Australia (Agnostida, Cambrian)Alcheringa 13: 175-191.Lu Yan Hao; Lin Huanling 1983: Zonation and correlation ofCambrian faunas in W. Zhejiang. Acta Geologica Sinica4: 317-328, pi. 1-2. [Chinese with English summary.]Lu Yan Hao; Lin Huanling 1989: The Cambrian trilobites oiwestern Zhejiang. Palaeontologica Sinica whole numhes178, new series B, number 25 : 1-285, 28 pi. [Chinese withEnglish summary.]Monke, H. 1903: Beitrage zur Geologie von Shantung 1.Obercambrische trilobiten von Y en-tsy-yai. Jahrbuch derPreussischen Geologischen Landesanstalt 22: 103-151.Mortimer , G. ; Schmidt-Thome, M. ; Tessensohn, F . 1984;Stratigraphic problems in the upper part of the Bowers

Supergroup, North Victoria Land, Antarctica. GeologischesJahrbuch, Reihe B, Heft 60, vol. 1: 83- 103 .Opik, A. A. 1961a: Alimentary caeca of agnostids and othertrilobites. Palaeontology 3: 410- 438 .


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Cooper et al.Cambrian trilobites, N Victoria Land 385Opik, A. A. 1961b: The geology and palaeontology of theheadwaters of the Burke River, Queensland. Bureau ofMineral Resources of Australia bulletin 53.Opik, A. A. 1963: Early Upper Cambrian fossils from Queensland.Bureau of Mineral Resources of Australia bulletin 64.Opik, A. A. 1967: The Mindyallan fauna of northwesternQueensland. Bureau of Mineral Resources of Australiabulletin 74, vol. 1, 2.Opik, A. A. 1979: Middle Cambrian agnostids: Systematics andbiostratigraphy. Bureau of Mineral R esources of Australiabulletin 172, vol. 1, 2.Palmer, A. R. 1954: The faunas of the Riley Formation in centralTexas. Journal of paleontology 28: 709-786.Palmer, A. R. 1962: Glyptagnostus and associated trilobites in theUnited States. U.S. Geological Survey professional paper374F.63p.Palmer, A. R. 1965: Trilobites of the Late Cambrian Pterocephaliidbiomere in the Great Basin, United States. United States

Geological Survey professional pa per 493: 1105.Peng Shan-chi 1992: Upper Cambrian biostratigraphy and trilobitefaunas of the Cili-Taoyuan area, northwestern Hunan,China. Association of Australasian Palaeontologistsmemoir 13.Powell, C. McA.; Neef, G.; Crane, D.; Jell, P. A.; Percival, I. G.1982: Significance of Late Cambrian (Idamean) fossils inthe Cupala Creek Formation, northwestern New SouthWales. Proceedings of the Linnean Society of New SouthWales 106: 127-150. 'Rasetti, F. 1944: Upper Cambrian tr ilobites from the LevisConglomerate. Journal of paleontology 18: 229258.Rasetti, F. 1954: Phytogeny of the Cambrian trilobite family

Catillicephalidae and the ontogeny of Welleraspis. Journalof paleontology 28: 599-612.Resser, C. E. 1938: Cambrian System (restricted) of the southernAppalachians. Geological Society of America special paper15 : 1-39.Robison, R. A. 1964: Late Middle Cambrian faunas from westernUtah. Journal of paleontology 38: 510566.Robison, R. A. 1984: Cambrian Agnostida of North America andGreenland, Part 1, Ptychagnostidae. University of Kansaspaleontological contributions paper 109. 59 p.Robison, R. A. 1988: Trilobites of the Holm Dal Formation (lateMiddle Cambrian), central North Greenland. In : Peel, J.S. ed . Stratigraphy and palaeontology of the Holm DalF or m at ion ( l a te Middle Cam br ian) , cen t r a l Nor thGreenland. Meddelelser om Gronland geoscience 20:23-54.Robison, R. A. 1994: Agnostoid tr ilobites from the HensonGletscher and Kap Stanton formations (Middle C ambrian),North Greenland. Granlands geologiske Unders0gelsebulletin 169: 25-77.Romanenko, E. V.; Romanenko, M. F. 1967: Some problems ofpaleogeography and Cambrian tr ilobites of the AltaiMountains. Izvestiya Altayskogo Otdela GeografichestrogoObshchestra Soyuza SSR 8: 6296 [in Russian].Rosova, A. V. 1963: Biostratigraphical scheme for the Upper andtop of the Middle Cambrian and new Upper Cambriantrilobites. Trudy Inst. Geol. Geofiz 9: 3-19.Sosova, A. V. 1964: Biostratigraphy and description of Middleand Upper Cam brian trilobites from the northwest SiberianPlatform. Moscow, Science Press (Nauka). Pp. 1-106.

Rowell, A. J.; Cooper, R. A.; Jago, J. B.; Braddock, P. 1983:Paleontology of the Lower Paleozoic of northern VictoriaLand. Brachiopods with Australian and New Zealandaffinities in the Spurs Formation. Antarctic journal of theUnited States 1 8: 18-20.Schmidt-Thome, M.; Wolfart, R. 1984: Tremadocian faunas(trilobites, brachiopods) from Reilly Ridge, North VictoriaLand, An tarctica. Newsletters in stratigraphy 13: 8893.Shaw, A. B. 1952: Paleontology of northwestern Vermont II. Faunaof the Upper Cambrian Rockledge Conglomerate near St.Albans. Journal of paleontology 26: 458- 483 .Shaw, A. B. 1966: Paleontology of northwestern Vermont X.Fossils from the (Cambrian) Skiels Corner Formation.Journal of paleontology 40: 269295.Shergold, J . H. 1975: Late Cambrian and Early Ordoviciantrilobites from the Burke River Structural Belt, westernQueensland, Australia. Bureau of Mineral Resources ofAustralia bulletin 153, vol. 1, 2.Shergold, J. H. 1980: Late Cambrian trilobites from the Chatsw orth

Limestone, western Queensland. Bureau of MineralResources of Australia bulletin 186.Shergold, J. H. 1982: Idamean (Late Cambrian) trilobites, BurkeRiver Structural Belt, western Queensland. Bureau ofMineral Resources of Australia bulletin 187.Shergold, J. H. 1993: The Iverian, a proposed Late Cambrian stage,and its subdivision in the Burke River Structural Belt,western Queensland. BMR journal of Australian geologyand geophysics 13: 345358.Shergold, J. H.; Cooper, R. A. 1985: Late Cambrian trilobites fromthe Mariner Group, northern Victoria Land, Antarctica.BMR journal of Australian geology and geophysics 9 :91-106.Shergold, J. H.; Webers, G. F. 1992: Late Dresbachian (Idamean)tr ilobite faunas from the Heritage Range, EllsworthMoun tains, West Antarctica. Geological Society of Americamemoir 170: 125-168.Shergold, J. H.; Cooper, R. A.; MacKinnon , D . I.; Yochelson, E.L. 1976: Late Cambrian Brachiopoda, Mollusca andTrilobita from Northern Victoria Land. Palaeontology 19:38-42.Shergold, J. H.; Laurie, J. H.; Sun Xiaowen 1990: Classificationand review of the trilobite order Agnostida Salter, 1864:an Australian perspective. Bureau of Mineral Resourcesof Australia report 295.Snajdr, M. 1958: Trilobiti ceskeho stredniho Kamb ria. RozpravyUstredniho iistavu Geologickeho 24 . 280 p.Solovjev, I. A.; Popov, L. E.; Samson ov, U. V. 1984: New data onthe Upper Cambrian fauna of the Ellsworth and PensacolaMoun tains, West Antarctica. Antarktika 23: 46- 71 .Sun, Y. C. 1935: The Upper Cambrian trilobite faunas of NorthChina. Palaeontologica Sinica series B, 2 (2): 1-69.Tullberg, S. A. 1880: Agnostusartena i de Kambriskaaflagringarne vid Andrarum. Sveriges GeologiskaUndersokning series C, 42: 1-38.Walcott, C. D. 1890: Fauna of the Lower Cambrian or OlenellusZone. United States Geological Survey (W ashington) 10thannual report 1: 509760.Walcott, C. D. 1905: Cambrian faunas of China. United StatesNational Museum proceedings 29: 1106.Walcott, C. D. 1911: Cambrian geology and paleontology 2, No. 4.Cambrian faunas of China. Smithsonian miscellaneouscollections 57: 69-108.


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Cooper et al.Cambrian trilobites, N Victoria Land 3879. Locality RS/f586 [GS13913], Reilly Ridge (lat. 7130'20"S,long. 16313'9"E). Spurs Formation.The locality contains only Doremataspis sp. and unassignedcranidium no. 4. The presence of Doremataspis suggests aGlyptagnostus stolidotus Zone age.10. Locality RS/f588 [GS13915], Reilly Ridge (lat. 7130'18"S,long. 16313'15"E). Spurs Formation.An agnostid pygidium, q uestionably assigned to Oxyagnostus,Idolagnostus dryas, Liostracina cf. nolens, and an asaphiscidpygidium are present. In Queensland, Oxyagnostus is know n fromthe G. stolidotus Zone (Opik 1967). Idolagnostus dryas is foundin all three Mindyallan zones in Queensland; Liostracina nolensis found in the G. stolidotus Zone only (Opik 1967). Age of theassemblage is therefore late Mindyallan.11 . Locali ty RSf /566 [GS13893] , ( la t . 7133'32"S, long.16318'30"E) . Spurs Formation (South End ConglomerateMember), southern end of Reilly Ridge.Apoo rly preserved assemblage comprisingAspidagnostus sp.,Meteoraspis? sp., Liostracina sp., and cranidium 6 sp. indet. isstrongly indicative of a late Mindyallan Glyptagnostus stolidotusZone age (Opik 1967, table 4).Fauna 6: Idamean12. Locality RS/f578 [GS13905], Reilly Ridge (lat. 7130'38"S,long. 16316'16"E). Spurs Formation.The locality contains only the early Idamean zone fossilGlyptagnostus reticulatus.13. Locality RS/f455 [GS13244], Reilly Ridge (lat. 7130'22"S,long. 16315'30"E). Spurs Formation.Pagodia sp. , Notoaphelaspis sp. , Changshanocephalus?suspicor, plus pygidium gen. e t sp. indet . 2 make up theassemblage. Notoaphelaspis is known from the Idamean of westernNew South Wales (Powell et al. 1982), and early Iverian rocksfrom the Mariner Glacier area of Northern V ictoria Land. In the

Ellsworth Mountains, Changshanocephalus? suspicor is knownfrom an Asphelaspis Zone fauna (Shergold & Webers 1992), whichis equivalent to the lower three Idamean zones in the Australianbiostratigraphic scale (Shergold et al. 1990). As noted in thedescription, Pagodia sp. probably belongs in Pagodia (Pagodia).which has a possible time range IdameanPayntonian (Shergold1975). Probable age of the locality is Idamean, its possible agerange is Idamean to early Iverian.14. Locality RS/f581 [GS13908], Reilly Ridge (lat. 7130'29"S.long. 163 5'55"E). Spurs Formation.The locality contains only Pagodia sp. and an unassignedlibrigena. Pagodia sp. also occurs at locality RS/f455, which isconsidered to be probably of Idamean age.15. Locality RS/f573 [GS13900], Reilly Ridge (lat. 7131'17"S,long. 16318'21"E). Spurs Formation.This fauna contains Kormagnostella sp., Pseudagnostus cf.idalis, Onchopeltis sp., Aphelaspis sp., Notoaphelasps horizontalissp . nov., Prochuangia sp., and Reillopleura braddocki gen. etsp . nov., cranidium indet. 7, hypostome indet. 1, and pygidia 1and 4.In Queensland, Kormagnostella is represented by K. inventafrom the top Idamean Stigmatoa diloma Zone, although in Siberiathe genus has a range extending down into an equivalent of theMindyallan (Shergold et al. 1990). Shergold & Webers (1992)described Kormagnostella cf. minuta from a fauna they correlatedwith the Stigmatoa diloma Zone. A species of Onchopeltis is alsoassociated with K. cf. minuta. Notoaphelaspis was first describedfrom an Idamean fauna in western New South Wales (Powell etal . 1982) , a l though Shergold & Cooper (1985) descr ibedNotoaphelaspis sp. from a fauna they suggested was immediatelypost-Idamean (i.e. Iverian) age. In Queensland, Prochuangia isfound from the Idamean Stigmatoa diloma Zone (Shergold 1982)up to the Iverian Peichiasthania secunda/Prochuangia glabellaZone. Hence, this fauna would appear to fit best into the latestIdamean Stigmatoa diloma Zone, but it could be of early Iverianage.

cambrian trilobites from northern victoria land, antarctica

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