middle and late pleistocene wild boar remains from

第四紀研究(The Quaternary Research) 40 (2) p. 149-160 April 2001

Middle and Late Pleistocene Wild Boar Remains from Locality 1 of Ube

Kosan Quarry in Yamaguchi Prefecture and from the Kannondo

Cave Site in Hiroshima Prefecture, Western Japan

Masakatsu Fujita*1 and Yoshinari Kawamura*2

A systematic description is given to a Middle Pleistocene remain (M3) from Locality 1 of Ube Kosan Quarry, and three Late Pleistocene remains (frontal bone, I2 and P4) from the Kannondo cave site. These remains are important to elucidate morpholog-ical characters of wild boars inhabited the mainland of Japan during the Pleistocene, because wild boar remains dated certainly as the Pleistocene are quite limited in Japan. The remains are compared with the living and Quaternary fossil suid species known from East Asia. The morphological characters of the remains are mostly coincident with those of Sus scrofa, an extant species now widely distributed inEurasia, but the exact identification is left pending owing to the insufficiency of the morphological data of the fossil species as well as the poor preservation of the present remains. The remains are therefore assigned to S. cf. scrofa. As regards the size of the remains, the M3 is larger than that of S. scrofa leucomystax, an extant subspecies of S. scrofa now distributed in Honshu-Shikoku-Kyushu, but is approximately as large as those of S. scrofa from other Middle Pleistocene localities. The other three remains are approximately as large as S. s. leucomystax. On the basis of the present study as well as the data so far obtained, it is inferred that the wild boar of S. scrofa or its allied form already inhabited Honshu-Shikoku-Kyushu in the middle Middle Pleistocene, and then decreased toward the Late Pleistocene. From the late Late Pleistocene to Holocene, it increased drastically, and became a dominant artiodactyl in the Holocene fauna of Honshu-Shikoku-Kyushu.

Key words: Middle Pleistocene, Late Pleistocene, wild boar, Ube Kosan Quarry,

Kannondo cave site, Japan

I. Introduction

Our knowledge on Pleistocene wild boars has been fragmented in Japan, owing to the scant-iness of fossil material. Until recently, wild boar remains dated as the Pleistocene had been almost limited to those from Tsukinoki in Akita Prefecture (Matsumoto 1915a, b, 1916; Tokunaga, 1927; Naora, 1944), Yoshizawa Quarry in Tochigi Prefecture (Shikama, 1933, 1937a, b, c, 1949; Naora, 1944, 1954), the Kannondo cave site in Hiroshima Prefecture

(Kawamura, 1980, 1992, 1995), Locality 1 of

Ube Kosan Quarry in Yamaguchi Prefecture

(Kawamura, 1988), and Matsugae Cave in Fukuoka Prefecture (Tokunaga, 1930; Naora, 1944, 1954), which are shown in Figure 1. Of the remains, those from Tsukinoki and Yoshizawa

Quarry were described systematically by Matsumoto (1915a) and Shikama (1949), respec-tively. But no systematic description was

given to the remains from Matsugae Cave, which were possibly lost during the World War II. On the other hand, the remains from the Kannondo cave site and Locality 1 of Ube Kosan Quarry were obtained in relatively

Received June 5, 2000, Accepted October 28, 2000. *1 Graduate School of Science

, Osaka City University. 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka, 558-8585, Japan.

E-mail:*2 Department of Earth Sciences

, Aichi University of Education. 1 Hirosawa, Igaya-cho, Kariya, 448-8542, Japan.

150 M. Fujita and Y. Kawamura April 2001

Fig. 1 Pleistocene fossil localities of wild boars in

the mainland of Japan

recent years, but their systematic descriptions have not been published so far.

Recent excavations of the Middle Pleistocene sediments of NT Cave produced rich wild boar remains which were systematically described in detail by Fujita et al. (2000) in the course of our studies on Quaternary wild boars of Japan and the adjacent areas. In the same coause, we here attempt to provide a systematic descrip-tion of the remains from Locality 1 of Ube Kosan Quarry and the Kannondo cave site. The remains are quite limited in number and

poor in preservation, but their systematic de-scription is expected to supplement important knowledge to the Pleistocene wild boars in Japan.

II. Fossil locality

Ube Kosan Quarry is a large limestone

quarry in Isa Cement Plant of Ube Kosan Com-

pany, which is situated at Isa, Mine City, Yamaguchi Prefecture. Fossil localities yield-ing Quaternary mammals have been occasion-

ally found in the quarry by the advance of limestone quarrying (Shikama and Okafuji, 1958, 1963; Shikama et al., 1967; Okafuji, 1971; Kawamura, 1988). Locality 1 named by Kawa-mura (1981) is one of the fossil localities, in which Pleistocene fossiliferous cave sediments were exposed. The stratigraphic sequence of the sediments and the f aunal list of the mam-mals obtained were given in Kawamura (1988), and all the sediments are considered to be of late Middle Pleistocene age (Kawamura, 1988, 1991; Kawamura et al., 1989). The wild boar remain described herein was obtained from the lowest part of the sediments (Layer 4b; vide Fig. 6 of Kawamura, 1988). The Kannondo cave site is located at

Nagano, Jinseki, Hiroshima Prefecture. This

site is one of the largest and most important

sites in the limestone cave and rockshelter sites collectively called the Taishaku-kyo sites dis-

tributed mainly along the gorge of the Taishaku River. Over 30 years' excavations

of the site have revealed that the upper part

of the sediments yields abundant artifacts, human bones and vertebrate remains of

Holocene age, while the lower part dated as the

Late Pleistocene produces abundant vertebrateremains, but lacks evident signs of humans. The stratigraphic sequence of the sediments and the disposition of the excavation grids are summarized in Kawamura (1988). In the upper

part of the sediments (Holocene horizons), wild boar remains are abundant, but they are very scarce and restricted to Horizon N and Horizon 0 (upper part) in the lower part (Late Pleisto-cene horizons), as already pointed out by Kawamura (1992). These horizons are approxi-mately dated between 20 and 40 ka (vide Fig. 2 of Kawamura, 1992).

III. Terminology and measuring method

The terminology of the skull and teeth a-dopted here is given in Figure 2. For the cusp terminology of the cheek teeth, we mainly follow Made (1996). The tooth measurements are taken parallel or perpendicular to the base line (BL) as shown in Figure 2. As regards the measurements, the following abbreviations are used: Lhp: Length from the menial surface of the

2001年4月 Pleistocene wild boar remains from western Japan 151

Fig. 2 Terminology and measuring method for describing the present wild boar remains

For the abbreviations see text.

hypopreconulid to the distal surface of the

pentapreconulid in M3. LLD: Labiolingual diameter of the crown

in I2, measured at 2mm above the lingual cervix, which is measurable in the I2 described here. Wa: Width of M3 between the buccal sur-face of the protoconid and the lingual surface of the metaconid. In the M3 described here, Wa is estimated from Wm by the regression line shown in Figure 6.

Wm: Width of M3 between the buccal sur-face of the hypoconid and the lingual surface of the entoconid, which is the same as the middle width of the crown by Fujita et al.

(2000).

IV. Systematic description

Order Artiodactyla Owen, 1848

Family Suidae Gray, 1821 Subfamily Suinae Zittel, 1893

Genus Sus Linnaeus, 1758

Sus cf. scrofa Linnaeus, 1758

(Figs. 3-5) Material-

Locality 1 of Ube Kosan Quarry: 1 fragmental left M3 from Layer 4b (ASM

703374) stored in the Akiyoshi-dai Museum of Natural History (listed in p. 102 of Kawamura, 1988). Kannondo cave site (Late Pleistocene hori-

zons): 1 skull fragment (right frontal bone) from

Horizon N (Layer 24-B in Grid J) numbered HUA-K04160 (listed in p. 68 of Kawamura, 1980)

;1 left I2 from Horizon N (Layer 24 in Grid HE) numbered HUA-K04161 (listed in p. 123 of Kawamura, 1995); 1 fragmental left P4 from the upper part of Horizon O (Layer 25-B in Grid

J) numbered HUA-K04162 (listed in p. 68 of Kawamura,1980). All the specimens are stored in the Department of Archaeology, Faculty of Letters, Hiroshima University.1)

Description

Skull-

The skull is represented only by a right fron-


tal bone from the Kannondo cave site (HUA-K 04160; Fig. 3). The frontonasal, frontolacrimal and coronal sutures form the anterior, ante-rolateral and posterior margins of the speci-men respectively, where the striated vertical surfaces of the sutures are observed. This sug-

gests that the nasal, lacrimal and parietal bones were easily removed from the frontal bone along the sutures, and thus the frontal bone belongs to a relatively young individual.

In lateral view, the dorsal surface of the ex-ternal plate of the frontal bone gently curves upward, and the orbital margin preserved is a circular arc (Fig. 3, B). The wall of the orbit forms a smooth spherical surface. In dorsal view, the external plate of the frontal bone is smooth except in its anteromedial part, where a shallow groove runs parallel to the lateral margin of the bone from the position of the supraorbital foramen whose dorsal wall is broken away (Fig. 3, A). The internal surface of the internal plate of the frontal bone is wrinkled. As a whole, the morphology and size of the orbit, the external and internal plates and the frontal sinuses between the plates are almost equal to those of the living S. scrofa leuco-mystax compared.

I2- I2 is represented only by HUA-K04161 from

the Kannondo cave site (Fig. 4, la-c). The crown is strongly worn, so that its lingual sur-face becomes only 1-2mm in height. Its labial surface, relatively well preserved, is smooth and weakly inflated. The occlusal surface forms a flat wear facet with a narrowly ellipti-cal occlusal outline (Fig. 4, 1b). The enamel exposed on the facet measures 0.6mm to 1.2 mm in thickness. The cervix is almost straight on the lingual surface, while it is remarkably undulated on the labial surface. A stout root is observed above the cervix. It extends dorso-distally, although its apical part is lost. The cross section of the root is elliptical at its broken end. No longitudinal grooves are ob-served on both labial and lingual surfaces of

the root. LLD measures 5.0mm. P4-

P4 is represented only by HUA-K04162 from the Kannondo cave site, which preserves the linguodistal part of the crown and the distal root (Fig. 4, 2a, b). The metaconid and hypo-conid form the distal part of a high cutting edge, which descends distally. The lingual sur-face of the crown is weakly concave between these cusps to form a shallow vertical valley. A small accessory cusp is attached on the distal surface of the hypoconid. The cusp is slightly lower than the hypoconid. A furrow between the cusp and hypoconid is short, but clearly observed. This furrow is blocked lingually byanother small accessory cusp, which is much

lower than the hypoconid. In lateral view, the

posterior margin of the crown steeply inclines

mesially. The cervix is nearly straight and

gently inclines mesially. The root is much

longer than the height of the crown preserved.

It extends straight ventrally, and tapers

apically. Its cross section is broadly elliptical.

M3- M3 is represented only by ASM703374 from

Locality 1 of Ube Kosan Quarry, which pre-serves the middle part of the crown (Fig. 5). The width of the crown decreases distally (Fig. 5, A). All the cusps preserved are unworn, but the enamel thickness is measurable on the ven-tral broken surface of the tooth. It ranges from 0.9mm to 1.8mm.

Of the cusps preserved, the hypopreconulid

is slightly lower and much smaller than the

entoconid which has nearly the same size and

height as the hypoconid. In occlusal view, the

hypopreconulid shows an elliptical outline

elongated transversely, and is situated relative-

ly buccal to the median line of the crown. Two

fine vertical furrows are observed on the lin-

gual and buccal surfaces of the cusp, respec-

tively. A narrow transverse groove separates

the hypopreconulid from the entoconid and

hypoconid. The lingual part of the groove is

deeper and more distinct than its buccal part.

The entoconid and hypoconid are conical,

1) In addition to these three specimens, Kawamura (1995) listed a canine fragment of Sus scrofa from the upper part of Horizon O in his Table 5 (p. 123). Our revision, however, has revealed that the fragment

does not belong to S. scrofa, but is probably assignable to a bear canine.


Fig. 3 Sus cf. scrofa from the Late Pleistocene horizons of the Kannondo cave site

Skull fragment numbered HUA-K04160.

Fig. 4 Sus cf. scrofa from the Late Pleistocene

horizons of the Kannondo cave site


Fig. 6 Relationship between Wa and Wm in the

living Sus scrofa leucomystax from Honshu.

A regression line (Wa=0.9597 Wm+1.4254)

is obtained in order to estimate Wa from

Wm in the M3 from Locality 1 of Ube

Kosan Quarry.

Fig. 5 Left M3 of Sus cf. scrofa from Locality 1 of

Ube Kosan Quarry (ASM703374)

and are opposite in position. They are sepa-

rated from each other by a central longitudinal

groove, which meets the transverse groove at

its mesial end. On the mesiobuccal surface of

the entoconid, there is a fine vertical furrow

which has a branch extending distobuccally. A

short vertical furrow is also observed on the

buccal surface of the entoconid and on the

lingual surface of the hypoconid, respectively.

The furrow on the buccal surface of the en-

toconid has a long branch extending mesio-

lingually. Furthermore, a longer vertical

groove is observed on the distal surface of the

entoconid and on the distal surface of the

hypoconid, respectively. The groove on the

distal surface of the hypoconid bifurcates near

the apex of the cusp. There is no cingulum on

the lingual surface of the entoconid and on the

buccal surface of the hypoconid.

The central longitudinal groove bifurcates

distally; one branch extends distobuccally,

while another extends distolingually. These

branches separate the pentapreconulid from

the hypoconid and entoconid. The penta-

preconulid is elliptical in occlusal view, and is considerably lower and smaller than the hypoconid and entoconid. The pentaectoconu-lid is attached on the buccal surface of the

pentapreconulid. This cusp is much smaller and lower than the pentapreconulid. Further-more, a very small accessory cusp is attached on the mesiobuccal base of the pentaectoco-nulid (Fig. 5, A, B). On the other hand, a cusp corresponding to the pentaectoconulid is ob-served on the lingual surface of the penta-

preconulid. This cusp has almost the same size and height as the pentaectoconulid. Addition-ally, two small indistinct accessory cusps are attached on its lingual base (Fig. 5, C). Lhp and Wm measure 16.3mm and 17.9mm,

respectively. Wa is estimated as 18.5mm from the regression line shown in Figure 6.

Comparison We compare the present fossil specimens

with the living and Quaternary fossil suid spe-cies known from East Asia. As regards the living suids of the Palaearctic and Oriental Regions, their taxonomy was recently revised by Corbet (1978), Groves (1981), and Corbet and Hill (1992). According to these authors, only one species of suids, S. scrofa, is now dis-tributed in East Asia. This species contains six East Asian subspecies, such as S. s. leucomystax


in the mainland of Japan (Honshu-Shikoku-Kyushu; excluding Hokkaido), S. s. riukiuanus in the Ryukyu Islands, S. s. ussuricus (=S. s.

gigas) in northeast China, Korea and Far East Russia, S. s. sibiricus in Transbaikalia and northern Mongolia, S. s. moupinensis from North and South China and S. s. taivanus in Taiwan (Groves, 1981). On the other hand, the following Quaternary fossil species have been recorded from East Asia.

Potamochoerus nodosarius Han (from Gigan- topithecus Cave, Liucheng, Guangxi, southern China; Early Pleistocene)

Dichoryphochoerus ultimus Han (ditto) Sus liuchengensis Han (ditto) S. australis Han (ditto) S. peii Han (ditto) S. xiaozhu Han, Xu et Yi (from Giganto-

pithecus Cave, and from Bijiashan, Liu- zhou, Guangxi, southern China; Early

Pleistocene)S. bijiashanensis Han, Xu et Yi (ditto) S. subtriquetra Xue (from Weinan, Shaanxi,

northern China; Early Pleistocene) S. lydekkeri Zdansky (from many fossil

localities of Early and Middle Pleistocene age in northern China)

Among these fossil species, S. subtriquetra was described on the basis of a pair of dentaries with canine, and one worn M2 only (Xue, 1981). This species is, therefore, impossible to com-

pare with the present fossil specimens. The remaining species except S. lydekkeri are

compared with the present fossil specimens on the basis of the descriptions and figures of Han et al. (1975) and Han (1987), because we could not observe the specimens of these species di-rectly in the Institute of Vertebrate Paleontolo-

gy and Paleoanthropology, Academia Sinica, and because these papers are the only data sources which provide us morphological char-acters of the species. On the other hand, we could observe many specimens of S. lydekkeri in the same institute. Thus our comparison with S. lydekkeri is based upon the direct obser-vation as well as the descriptions and figures of Zdansky (1928) and Young (1932). Of the fossil species listed above, Potamo-

choerus nodosarius and Dichoryphochoerus

ultimus are problematic in their generic alloca-

tion, judging from the recent revision of fossil suids in the Indian Subcontinent (Pickford, 1988). But we use Han's original allocation here, because we did not observe their speci-mens and their generic allocation is not the aim of this paper. On the other hand, the taxonom-ic position of S. lydekkeri was discussed by Fujita et al. (2000) who considered it as a chron-ological subspecies of S. scrofa, because its characters are accommodated in the range of variation of S. scrofa, judging from the recent taxonomical concept of S. scrofa (Corbet, 1978; Groves, 1981; Corbet and Hill, 1992). We here follow Fujita et al. (2000), and treat S. lydekkeri as S. scrofa lydekkeri. Among the fossil specimens described here, the skull from the Kannondo cave site is com-

parable with that of the living S. scrofa leucomystax from Honshu as well as those of S. scrofa from the Middle Pleistocene of NT Cave, S. scrofa lydekkeri from the Middle Pleistocene of Locality 1 of Zhoukoudian and P. nodosarius from the Lower Pleistocene of Gigantopithecus Cave. The comparisons with D. ultimus, S. liuchengensis, S. australis, S. peii, S. xiaozhu and S. bijiashanensis are, however, impossible, be-cause the morphology of their skulls is un-known (vide Han et al., 1975; Han,1987). The present skull is very similar to that of S.

scrofa leucomystax in size and shape. It is also similar to S. scrofa from NT Cave and S. s. lydekkeri from Locality 1 of Zhoukoudian, but is considerably smaller than these two. On the other hand, the skull of P. nodosarius is differ-ent from the present skull in having the exter-nal plate of the frontal bone steeply elevated

posteriorly and the supraorbital foramen positioned more posteriorly. Furthermore the groove extending anteiorly from the foramen is deeper and more distinct in the skull of P. nodosarius. The I2 from the Kannondo cave site is compa-

rable with those of the living S. scrofa leucomystax, S. scrofa from NT Cave and S. scrofa lydekkeri from Locality 1 of Zhoukou-dian. The I2 coincides with that of S. scrofa leucomystax in morphology and size (Fig. 7). It is also similar to those of S. scrofa from NT Cave and S. scrofa lydekkeri from Locality 1 of Zhoukoudian in morphology, but is considera-


Fig. 7 Size variation in LLD of I2 and Wa of M3 in the subspecies of the living Sus scrofa, in

comparison with that in the fossils (S. cf. scrofa from the Kannondo cave site and Locality 1

of Ube Kosan Quarry, S. scrofa from NT Cave and S. s. lydekkeri from Locality 1 of

Zhoukoudian)

This figure shows that the size variation of the fossils is accommodated in that of the living

S. scrofa. In the M3 from Locality 1 of Ube Kosan Quarry, Wa is estimated from Wm by the

regression line of Figure 6.

bly smaller. The P4 from the Kannondo cave site is com-

parable with those of the living S. scrofa leucomystax, S. scrofa from NT Cave and S. s. lydekkeri from Locality 1 of Zhoukoudian as well as those of D. ultimus and P. nodosarius. The P4 is very similar to that of the living S. scrofa leucomystax in morphology and size, as far as the preserved part is concerned. The P4 also resembles those of S. scrofa from NT Cave and S. s. lydekkeri from Locality 1 of Zhoukou-dian in general, but it is considerably smaller and its distolingual accessory cusp is better developed. On the other hand, the P4 differs from those of D. ultimus and P. nodosarius in having a relatively slenderer crown and less cuspidate pattern with a high cutting edge. Additionally, the descriptions and figures of P4 of S. liuchengensis, S. australis, S. peii and S. xiaoxhu are obscure in Han et al. (1975) and Han

(1987), and the comparisons with the present P4 are impossible. But it can be said that the P4 of S. xiaoxhu is decidedly smaller than the present P4.

The M3 from Locality 1 of Ube Kosan Quarry is comparable with those of the living S. scrofa leucomystax, S. scrofa from NT Cave and S. s. lydekkeri from Locality 1 of Zhoukoudian as well as those of D. ultimus, P. nodosarius, S. liuchengensis, S. australis, S. peii, S. xiaoxhu and S. bijiashanensis. The M3 is similar to that of the living S. scrofa leucomystax in morphology, but is considerably larger (Figs. 7 and 8). The M3 is coincident with that of S. scrofa from NT Cave in size and shape and with that of S. s. lydekkeri from Locality 1 of Zhoukoudian in shape, but is somewhat smaller than that of S. s. lydekkeri (Fig. 7). On the other hand, the M3 is distinct from

those of D. ultimus and P. nodosarius in having thinner enamel, better developed furrows on the cusps and better developed hypopre-conulid and pentapreconulid. The M3 is also different from S. liuchengensis, S. australis, S.

peii, S. xiaoxhu and S. bijiashanensis in having better developed furrows on the cusps, and better developed hypopreconulid and/or pen-tapreconulid. In addition to these discriminat-


Fig. 8 Scatter diagram showing the relationship

between Lhp and Wm in M3 of the fossil

and living wild boars of Sus scrofa or its

allied form

ing characters, M3 of S. xiaozhu is easily distin-

guishable from the present M3 in its much

smaller size.

In conclusion, the present fossil specimens are morphologically similar to the living S. scrofa leucomystax, S. scrofa from NT Cave and S. s. lydekkeri from Locality 1 of Zhoukoudian. Of the specimens, the M3 from Locality 1 of Ube Kosan Quarry approximates that of S. scrofa from NT Cave in size, which are generally larger than the living S. scrofa leucomystax. The remaining specimens from the Kannondo cave site are coincident with the living S. s. leucomystax in size, and therefore smaller than S. scrofa from NT Cave and S. s. lydekkeri from Locality 1 of Zhoukoudian. These size differ-ences are considered to be intraspecific, as Fujita et al. (2000) considered (Fig. 7). On the other hand, all the fossil specimens

described here differ from the Quaternary fossil species listed above, as far as the compa-rable parts are concerned. The comparisons are, however, quite limited owing to the insuffi-ciency of the morphological data of the fossil species, as well as the poor preservation of the

present fossil specimens. The morphological similarity to the living S. scrofa leucomystax, S. scrofa from NT Cave and S. s. lydekkeri sug-

gests that the specimens are taxonomically

near to S. scrofa, but the insufficiency of the comparisons prevents us from identifying them as S. scrofa. Consequently, we assign them to S. cf. scrofa herein. Discussion

The M3 from Locality 1 of Ube Kosan Quarry is the only representative of wild boars in the late Middle Pleistocene of Honshu-Shikoku-Kyushu, when we adopt the chronological framework given by Kawamura (1988, 1991) and Kawamura et al. (1989). This specimen re-ferred to S. cf. scrofa above, resembles the M3 of S. scrofa from the middle Middle Pleistocene of NT Cave in shape and size. In the mammali-an assemblage of NT Cave, S. scrofa is relative-ly abundant (Kawamura et al., 1998), while S. cf. scrofa is rare in the assemblage of Locality 1 ofUbe Kosan Quarry, and no wild boar remains are found in the assemblage of Locality 3 of Ube Kosan Quarry which is also dated as the late Middle Pleistocene (Kawamura, 1988). These facts suggest that the wild boar (S. scrofa or S. cf. scrofa) decreased in number from the middle Middle Pleistocene to the late Middle Pleistocene without any remarkable morphological and size changes. The remains from the Kannondo cave site

are also the only representatives of wild boars certainly dated as the late Late Pleistocene in Honshu-Shikoku-Kyushu. They are also as-signed to S. cf. scrofa, and are coincident with the living S. scrofa leucomystax in morphology and size. Thus they are smaller than the middle and late Middle Pleistocene wild boars. The wild boar in Honshu-Shikoku-Kyushu

probably diminished in size from the late Middle Pleistocene to the late Late Pleistocene. On the other hand, wild boar remains exactly dated as the early Late Pleistocene are un-known. These facts indicate that the wild boaralmost extinguished from the late Middle Pleis-tocene to early Late Pleistocene. In the late Late Pleistocene, however, it appeared in small number, and then drastically increased at the beginning of the Holocene, when we take abundant occurrence of wild boars in archaeo-logical sites and fossil localities of Holocene age into consideration, as already pointed out by Kawamura (1992).


V. Conclusion

The comparisons with living and Quaterna-ry fossil suid species of East Asia indicate that the Middle Pleistocene remain from Locality 1 of Ube Kosan Quarry (left M3) and the Late Pleistocene remains from the Kannondo cave site (right frontal bone, left I2 and left P4) are similar to Sus scrofa in morphology. But they are allocated only to S. cf. scrofa because of their poor preservation and the insufficiency of the comparisons. Among the remains, the M3 is larger than those of the living S. scrofa leucomystax from Honshu, but is nearly as large as those of S. scrofa from NT Cave. The size of the other three is coincident with that of the living S. s. leucomystax. On the basis of the present study and the

data so far obtained, it is inferred that the wild

boar of S. scrofa or its allied form already

inhabited Honshu-Shikoku-Kyushu in the middle Middle Pleistocene, and decreased in

number toward the Late Pleistocene. The wild

boar of the Middle Pleistocene had a large size

comparable to or somewhat smaller than S. s. lydekkeri of North China. In the early Late

Pleistocene, it is likely that the wild boar was

very rare or almost became extinct in Honshu-Shikoku-Kyushu. In the late Late Pleistocene

localities, it was rarely found, which suggests

the revival of the wild boar in this time. The

wild boar of the late Late Pleistocene was smaller than that of the Middle Pleistocene,

and was nearly as large as that of the Holocene

and living S. s. leucomystax. The wild boar drastically increased at the beginning of the

Holocene, and became a dominant element of

the Holocene terrestrial mammal fauna in Honshu-Shikoku-Kyushu.

Acknowledgments

We are grateful to Messrs T. Haikawa and S. Sugimura of the Akiyoshi-dai Museum of Nat-ural History for assisting one of us (Y. Ka-wamura) with the field survey of 1978 in Ube Kosan Quarry, and for giving him many facilities in the research activities in their museum. The staffs of the quarry (Isa Cement Plant of Ube Kosan Company) including Mr. F.

Shibata permitted him the field survey and

provided useful pieces of information. We also

thank the staffs of the Department of Archaeol-

ogy, Hiroshima University including Mr. T.

Nakagoshi, Prof. T. Kawagoe, Prof. M. Kawase,

Associate Prof. K. Furuse for giving us permis-

sion, facilities and encouragement to study the

specimens from the Kannondo cave site.

Thanks are due to Prof. T. Inada (Okayama University) and Dr. Jin Chang-zhu (Institute of Vertebrate Paleontology and Paleoanthropol-ogy, Academia Sinica=IVPP) who permitted and assisted us to access the comparative spec-imens. The measurements of the collections of the following institutions by us are used to draw Figure 7: American Museum of Natural History (AMNH), British Museum of Natural History (BMNH), IVPP, Department of Anato-my, Osaka City University (OCU), ZoologicalInstitute, Academia Sinica (ZI). We are grateful to Prof. R. H. Tedford, Dr. X. M. Wang and Ms. F. Brady (AMNH); Dr. J. Hooker, Mr. A. Cur-rant and Dr. P. D. Jenkins (BMNH); Dr. M. Abe

(OCU); Prof. Feng Z. J. and Ms. M. Luo (ZI) and many other staffs of the institutions who

permitted and assisted us to access the collec-tions in their care and gave us many facilities. We also thank to many people who helped us to collect the living specimens of S. scrofa leucomystax from Honshu. This study was partly supported by the

Grants-in-Aid from the Ministry of Education, Science, Sports and Culture, Japan (project nos. 11301014 and 09208101).

References

Corbet, G. B. (1978) The mammals of the Palaearctic Region: A taxonomic review. 314 p, British Museum

(Natural History) and Cornell Univ. Press. Corbet, G. B. and Hill, J. E. (1992) The mammals of the

Indomalayan Region: A systematic review. 488 p, Oxford Univ. Press.

Fujita, M., Kawamura, Y. and Murase, N. (2000) Middle Pleistocene wild boar remains from NT

Cave, Niimi, Okayama Prefecture, west Japan. Jour. Geosci., Osaka City Univ., 43, 57-95.

Groves, C. (1981) Ancestors for the pigs: Taxonomy and phylogeny of the genus Sus. Dept. Prehist. Res.

School Pacific Studies, Australian Nat. Univ., Tech- nical Bull., 3, 1-96.

Han D. F. (1987) Artiodactyla fossils from Liucheng Gigantopithecus Cave in Guangxi. Mem. Inst. Vert.


Palaeont. Palaeoanthrop. Acad. Sinica, 18, 135-208, pls. 1-12. (C+E)

Han D. F., Xu C. H. and Yi G. Y. (1975) Quaternary mammalian fossils from Bijiashan, Liuzhou,

Guangxi. Vert. Palas., 13, 250-256, pls. l-2. (C) Kawamura, Y. (1980) Mammalian remains of the Pre-

Jomon Period from Taishaku-Kannondo Cave Site (Part 1). Mammalian remains obtained by the

excavation of 1975. Ann. Bull. Hiroshima Univ. Taishaku-kyo Sites Res. Centre, 3, 61-74, pls. 11-13. (J)

Kawamura, Y. (1981) Micro-mammalian remains from Ube Kosan Quarry, Mine, Yamaguchi Prefecture

(Part 1). Abst. 88th Ann. Meet. Geol. Soc. Japan, 280. (J)

Kawamura, Y. (1988) Quaternary rodent faunas in the Japanese Islands (Part 1). Mem. Fac. Sci. Kyoto

Univ., Ser. Geol. Min., 53, 31-348. Kawamura, Y. (1991) Quaternary mammalian faunas

in the Japanese Islands. The Quat. Res. (Daiyonki- Kenkyu), 30, 213-220.

Kawamura, Y. (1992) Stratigraphic distribution of mammals in the Taishaku-kyo Sites, Hiroshima

Prefecture, west Japan. The Quat. Res. (Daiyonki- Kenkyu), 31, 1-12. (J+E)

Kawamura, Y. (1995) Mammalian remains of the Pre- Jomon Period from Taishaku Kannondo Cave Site (Part 4). Mammalian remains obtained by the exca-

vation of 1979. Ann. Bull. Hiroshima Univ. Taishaku-kyo Sites Res. Centre, 10, 118-126, pl. 25. (J)

Kawamura, Y., Fujita, M. and Murase, N. (1998) Qua- ternary mammals from NT Cave at Tarumi, Niimi,

Okayama Prefecture. Inada, T. (ed.) Report of the Grant-in-Aid from the Ministry of Education, Science

Sports and Culture Japan, for the academic years 1995-1997: 12-21. (J)

Kawamura, Y., Kamei, T. and Taruno, H. (1989) Middle and Late Pleistocene mammalian faunas in

Japan. The Quat. Res. (Daiyonki-Kenkyu), 28, 317- 326. (J+E)

Made, J. van der (1996) Listriodontinae (Suidae, Mam- malia), their evolution, systematics and distribu-

tion in time and space. Contr. Tertiary and Quater- nary Geol., 33, 3-254.

Matsumoto, H. (1915a) On some fossil mammals from Tsukinoki, Ugo. Sci. Rep. Tohoku Imp. Univ., 2nd

Ser. 3, 39-48, pls. 16-19.Matsumoto, H. (1915b) Origin of the Japanese wild

boar. Gendai-no-kagaku, 3, 73-82 (J) Matsumoto, H. (1916) List of mammalian fossil beds

in Japan. Jour. Geol. Soc. Tokyo, 23, 291-299. (J) Naora, N. (1944) History of Japanese mammals. 265 p,

Yotokusha. (J) Naora, N. (1954) Old stone age in Japan. 298 p, Neiraku-

shobo. (J) Okafuji, G. (1971) Fossil monograph of Akiyoshi-dai

and its neighbourhood, Yamaguchi Prefecture, Japan (Carboniferous, Late Triassic and Pleistocene). 147 p,

Educational. Foundation, Yamaguchi Prefecture. (J)

Pickford, M. (1988) Revision of the Miocene Suidae of the Indian Subcontinent. Munchner Geowiss. Abh.,

Ser. A, 12, 1-91.Shikama, T. (1933) On the Kuzuu Formation. Jour.

Geol. Soc. Tokyo, 40, 700-722. (J) Shikama, T. (1937a) Geological survey of the Kuzuu

Formation (fissure deposits). Contr. Inst. Geol. Palaeont. Tohoku Imp. Univ., Jap. Lang, 27,1-34, pls.

1-18. (J) Shikama, T. (1937b) Ossiferous fissure deposits of

Kuzuu, Totigi Prefecture. Proc. Imp. Acad. Tokyo, 13, 364-367.

Shikama, T. (1937c) Short notes on the excavation of the ossiferous fissures and caves in Kuzuu during

the years 1931 to 1936. Jour. Geol. Soc. Japan, 44, 405- 420. (J+E)

Shikama, T. (1949) The Kuzuu Ossuaries: Geological and palaeontological studies of the limestone fissure deposits, in Kuzuu, Totigi Prefecture. Sci.

Rep. Tohoku Univ., 2nd Ser. (Geol.), 23, 1-209+1-26, pls. 1-32.

Shikama, T., Hasegawa, Y, and Okafuji, G. (1967) On a rhinocerid skull from Isa, Yamaguchi Prefecture,

Japan. Bull. Nat. Sci. Mus.,10, 455-462, pls. 1-2. Shikama, T. and Okafuji, G. (1958) Quaternary cave

and fissure deposits and their fossils in Akiyosi District, Yamaguti Prefecture. Sci. Rep. Yokohama

Nat. Univ., Sect. 2, 7, 43-103, pls. 4-15. Shikama, T. and Okafuji, G. (1963) On some Chou-

koutien mammals from Isa, Yamaguchi Prefecture, Japan. Sci. Rep. Yokohama Nat. Univ., Sect. 2, 9, 51-

58, pl. 2.Tokunaga, S. (1927) Mammalian fossils of the Imp.

Geol. Survey destroyed by the Earthquake of 1923. Jour. Geogr., 39, 500-501, pls. 13-16. (J)

Tokunaga, S. (1930) Remains of the Pleistocene den dwellers in Honshu, Kyushu and Korea. Nippon

Gakujutsu Kyokai Hokoku, 6, 175-178. (J) Xue X. X. (1981) An Early Pleistocene mammalian

fauna and its stratigraphy of the River You, Weinan, Shensi. Vert. Palas.,19, 35-44, pls. 1-2. (C+ E)

Young, C. C. (1932) On the Artiodactyla from the Sinanthropus Site at Chouk'outein. Palaeont. Sinica,

Ser. C, 8, fasc. 2, 1-100, pls. 1-29. Zdansky, O. (1928) Die Saugetiere der Quartarfauna

von Chou-K'ou-Tien. Palaeont. Sinica, Ser. C, 5, fasc. 4, 1-146, pls. 1-16.

(J) in Japanese, (C) in Chinese, (J+E) in Japanese with English abstract or resume, (C+E) in Chinese with English abstract or summary


山口県宇部興産採石場第1地点と広島県帝釈観音堂洞窟遺跡産の

中・後期更新世イノシシ化石

藤田正勝*1・河村善也*2

(要旨)

山口県美祢市にある宇部興産採石場第1地点から産出

した中期更新世のイノシシ化石1点(下顎第3大臼歯)

と,広島県神石町にある帝釈観音堂洞窟遺跡から産出し

た後期更新世のイノシシ化石3点(前頭骨,上顎第2切

歯,下顎第4小臼歯)を系統分類学的に記載し,それらの

形態的特徴を明らかにした.わが国では確実に更新世の

イノシシ化石といえるものは少なく,これらは更新世の

本州・四国・九州に分布したイノシシの特徴を知る上で

貴重な材料となる.これらの化石を東アジア産のイノシ

シ類の現生種および第四紀の化石種と比較した結果,現

在ユーラシアに広く分布するSus scrofaにその形態的

特徴がよく一致することがわかった.しかし,東アジァ

産化石種の形態に関するデータは十分でなく,今回の化

石標本も数が少ない上に保存も悪く,十分な比較が行え

なかったので,今回はこれらの化石をS.cf.scrofaとす

るにとどめる.これらの化石のうち,宇部興産採石場第

1地点産のものは,現在の本州・四国・九州に分布する

S.scrofaの亜種S.s.leucomystaxのそれより大きく,

ほかの中期更新世の化石産地のものとほぼ同じ大きさで

あった.しかし,帝釈観音堂洞窟遺跡産の化石はS.s

leucomystaxとほぼ同じ大きさであった.今回の研究の

結果とこれまでに得られているデータから,S.scrofaや

それに近いイノシシは中期更新世中期にはすでに本州・

四国・九州に生息していて,そこから後期更新世にかけ

て数が減少し,さらに後期更新世後期から完新世にかけ

ては逆に急増した後,この地域の完新世の動物相の主要

な構成要素となったと推定される.

*1大阪市立大学大学院理学研究科〒558-8585大阪市住吉区杉本3-3-138 .E-mail9

*2愛知教育大学地学教室〒448-8542愛知県刈谷市井ヶ谷町広沢1 .

middle and late pleistocene wild boar remains from

Documents