Identifying AGRRA Corals: Part 4Identifying AGRRA Corals: Part 4Branching CoralsBranching Corals

Judith Lang and Kenneth MarksJudith Lang and Kenneth MarksAtlantic and Gulf Rapid Reef Assessment (AGRRA) ProgramAtlantic and Gulf Rapid Reef Assessment (AGRRA) Program

Revision: 2012-03-09Revision: 2012-03-09 www.agrra.orgwww.agrra.org

The following images are Copyright ©by New World Publications

and by other photographers.

Permission is granted to use the photographs and slides in this presentation with the

AGRRA Program and, with attribution, for other valid educational purposes..

All other uses are strictly prohibited.

For images used in Part 4, our special thanks to:K. Desai, P. Humann, W. Precht, C. Rogers, R. Steneck, M. Vermeij, E. Weil, A. YniguezA. Yniguez

Adapted from P.R. Kramer

Colony shape – massive (= mound, columnar, heavy plates), crust, plate, branching

Colony size range – small to big

Colony surface – bumpy, smooth, ridged

Polyp size – small to big

Polyp shape – round, elliptical, irregular, Y-shaped, meandroid (= short or long ridges and valleys)

Polyp colour – brown, tan, yellow, olive, green, redSeptal shape – fat, thin; smooth, toothed

Reminder: What to Look for Underwater

The stony corals illustrated here are limited to species that are found in the wider Caribbean at depths (<20 m) that are typical of most AGRRA surveys.

The names of some corals are changing as a result of modern research. Expect updates!

For each species:(number in m and ft = maximum colony size)

Reminder: AGRRA Coral Species

Reminder: Coding Corals in AGRRA Surveys

Use the CARICOMP-based coral codes.

The coral code for a genus is the first 4 letters of its genus name.

ACRO = AcroporaUse the genus code whenever you are unsure of a coral’s species identity.

The coral code for a species is the first letter of the genus name followed by the first 3 letters of its species name.

APAL = Acropora palmata

Colony Boundaries in Branching Corals

Branching corals are easily broken and scattered, thus colony boundaries are often indistinct.

A. palmata APAL M. auretenra MAUR

P. porites PPOR

Porites porites PPOR

thick (>2 cm), branches, many with blunt tips

elongate polyps often expand during the day

light grey, cream, yellow-brown or blue

Porites porites PPOR

polyps are alive only near the branch tips in large colonies

(clumps to > 2 m/6 ft wide)

Porites furcata PFUR

long, ~1-2 cm wide, “finger-like” branches, many with rounded tips

grey, tan or brown

(clumps to > 2 m/6 ft wide)

Porites furcata PFUR

How differs from Porites porites:branches are thinner, longer, more widely spaced, with more rounded tips

often darker colours (these are pale from bleaching)

P. porites P. furcata PPOR PFUR

Which is Which?

Porites divaricata PDIV

thin (<1 cm), short, widely-spaced branches, many subdivided near tip (“Y-shaped”)

grey, yellow-brown to brown

(clumps to ~ 30 cm/1 ft wide)

Porites divaricata PDIV

How differs from Porites furcata:

thinner, shorter, more widely-spaced branches, more often divided at tips

smaller colonies

rare on fore reefs

P. divaricata P. porites P. furcata PDIV PPOR PFUR

© E. Weil

Which is Which?

Complications!

Some colonies look like “intermediates” ofP. porites and P. furcata

or ofP. furcata and P. divaricata

If unsure of species identity, code as Porites “digitate” PDIG

Madracis auretenra MAUR

thin, fragile, near-parallel, and densely packed branches with blunt tips

polyps often expanded by day (look “fuzzy”)

cream, yellow or yellow-brown

(usually to ~ 1.5 m/5 ft)

*formerly called M. mirabilis, described as a new species by Locke et al. (2007)

Madracis auretenra MAURclumps many meters/10s of feet wide occur in sheltered habitats

M. auretenra P. porites MAUR PPOR(pale yellow) (light grey)

Which is Which?

Madracis decactis MDEC

short, stubby knobs, crusts, lumpy crusts or short nodules

distinct polyps, with conspicuous septa (usually 10/polyp)

green, tan, grey, yellow-brown or dark brown

(to ~ 15 cm/6 in)

Madracis decactis MDEC

How knobby morph differs from Madracis auretenra:

forms stubby knobs, notbranches

darker colours

Madracis decactis MDEC

How knobby morph differs from Porites porites:

forms stubby knobs, notbranches

septa are distinct (can becounted underwater)

darker colours

M. decactis P. porites MDEC PPOR

Which is Which?

M. auretenra M. decactis MAUR MDEC

Which is Which?

Madracis carmabi MCARand Madracis formosa MFOR

Both have thick branches with blunt tips

8 septa/polyp (to ~ 2 m/6 ft)

10 septa/polyp, perhapsa hybrid of M. formosa and M. decactis

or M. pharensis (Frade et al. 2010)

Madracis carmabi MCARand Madracis formosa MFOR

How differ from M. decactis:thick, near-parallelbranches, with flattened tips

+ from M. auretenra:thicker, more widely spaced branches

Code as MADR if unsure of species identity

Madracis formosa MFOR

M. formosa/ M. carmabi M. auretenra M. decactis MADR MAUR MDEC

Which is Which?

Oculina diffusa ODIFshort, somewhat twisted branches with large, distinct polyps

yellow-brown, or may lack zooxanthellae

(to ~ 30 cm/1 ft)

© P. Humann

Oculina diffusa ODIF

How differs from Madracis auretenra:

polyps are larger and more exert (protrude more above the skeleton)

M. auretenra O. diffusa MAUR ODIF

Which is Which?

Acropora ACRO

All species:tiny (axial) polyps at the tips of actively growing branches are colourless (look white)

lateral (radial) polyps are brown or yellow-brown (contain zooxanthellae)

Acropora palmataAcropora palmata

Acropora cervicornisAcropora cervicornis

Acropora palmata APAL

large branches, cylindrical where exposed to waves

can form large colonies (to ~ 4m/12 ft)

Acropora palmata APAL

branches flatten in calm water

Acropora cervicornis ACER

long, slender (1-3 cm), round branches

(to ~ 3m/10 ft)

Acropora cervicornis ACERcan form very large clumps

Acropora prolifera APRO

a hybrid of A. palmata and A. cervicornis

branches (0.5-2 cm wide) look like “intermediates” between those of A. palmata and of A. cervicornis

(to ~ 1.5 m/5 ft)

Acropora prolifera APRO

How “palmate” form differs from A. palmata: short branches don’tfuse into large thickmasses

smaller colonies

Acropora prolifera APROHow bushy form differs from A. cervicornis:branches are closer together, sometimes narrower, and more likely to have a horizontal orientation

A. prolifera A. palmata A. cervicornis APRO APAL ACER

Which is Which?

Millepora spp. MILL

How Millepora differs from the scleractinian stony corals:

Millepora complanata

tiny polyps armed with stinging tentacles that protrude from the small pores visible in colony surfaces

Millepora complanata MCOM

narrow, upright lobes above an encrusting base

yellow to tan

(to ~ 60 cm/2 ft)

Millepora complanata MCOM

A distinctive form of MCOM with short blades that often split to form narrow “boxes” is classified by some asMillepora striata (MSTR).

Millepora squarrosa MSQU

short, box-like structures with thick walls, blunt tips above an encrusting base

tan to yellow-brown with characteristic reddish, pinkish or lavendar tints

(to ~ 5 cm/2 in)

M. complanata M. squarrosa MCOM MSQU

Which is Which?