Identifying AGRRA Corals: Part 4 Branching and Nodular Corals
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Identifying AGRRA Corals: Part 4 Branching and Nodular Corals © K. Marks © K. Marks © K. Marks Revision: 2013-05-22 Judith Lang Images in this presentation are Copyright © by Ken Marks, New World Publications and by other photographers. Copyright © Ocean Research & Education Foundation Permission is granted to use this Powerpoint presentation for educational purposes 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: M. Brandt, K. Desai, I. Drysdale, D. Fenner, P. Humann, W. Precht, C. Rogers, R. Steneck, M. Vermeij, E. Weil, A. Yñiguez Reminder: What to Look for Underwater 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 Polyp colour – brown, tan, yellow, olive, green, red Septal shape – fat, thin; smooth, toothed Adapted from P.R. Kramer Reminder: AGRRA Coral Species The stony corals illustrated here are limited to species found in the wider Caribbean at depths (<20 m) typical of most AGRRA surveys. The names of some of these corals are changing as a result of modern research. More taxa are added as we gain underwater photographs of species that are rare and/or of geographically limited distributions. Expect periodic updates! Photographers who can enhance this collection are encouraged to contact Judy Lang at: [email protected] or [email protected] For each species: (# in m and ft) = maximum colony size Remember: Coding Corals in AGRRA Surveys Use the CARICOMP-based coral codes. The coral code for a genus (or occasionally a species complex) is the first 4 letters of its genus name and should be used whenever you are unsure of a coral’s species identity: MADR = Madracis The coral code for a species is the first letter of the genus name followed by the first 3 letters of its species name: MSEN = Madracis senaria Codes are shown before names appear on the introductory slide for species that are commonly recorded in AGRRA surveys. Colony Boundaries in Branching Corals Branching corals are easily broken and scattered, thus colony boundaries are often indistinct. © C. Rogers P. porites PPOR © C. Rogers © E. Weil A. palmata APAL M. auretenra MAUR Digitate (finger) Porites All species: tall thin polyps look fuzzy when expanded smooth branch surfaces are seen when polyps contract © K. Marks Porites porites PPOR Porites porites PPOR thick (>2 cm/1 in), irregularly shaped branches, many PPOR with blunt tips elongate polyps often expand during the day light grey, cream, yellow- brown or blue PPOR © R. Steneck © K. Marks Porites porites PPOR examples of variation in colour and branch shape (clumps to > 2 m/6 ft wide) © K. Marks © K. Marks © K. Marks © C. Rogers © K. Marks Porites porites PPOR polyps are alive only near the branch tips in large colonies © M. Brandt © K. Desai Porites furcata PFUR long, “finger-like” branches, (~ 1-2 cm/.4-.8 in. wide), PFUR many with rounded tips grey, tan or shades of brown (clumps to > 2 m/6 ft wide) © K. Marks PFUR PFUR © C. Rogers © K. Marks Porites furcata PFUR How differs from P. porites: branches are thinner, longer, more widely spaced, less irregular in shape, and with more rounded tips often darker colours (these are pale from bleaching) © K. Marks © K. Marks Which is Which? © E. Weil P. porites P. furcata PPOR PFUR Porites divaricata PDIV thin (<1 cm/.4 in), short, widely-spaced branches, many subdivided near tip PDIV (“Y-shaped”) grey, yellow-brown to brown (clumps to ~ 30 cm/1 ft wide) © C. Rogers Porites divaricata PDIV How differs from P. furcata: thinner, shorter, more widely- spaced branches, more often divided at tips fully grown colonies are smaller rare on fore reefs © C. Rogers Which is Which? © E. Weil P. divaricata P. furcata PDIV PFUR Which is Which? © E. Weil © K. Marks © E. Weil P. divaricata P. porites P. furcata PDIV PPOR PFUR Complications! Some colonies look like “intermediates” of P. porites and P. furcata or of P. furcata and P. divaricata If unsure of species identity, code as Porites “digitate” PDIG Madracis MADR All species: small, round polyps are often exsert (“outies”) polyps look fuzzy when tentacles are expanded © K. Marks Madracis auretenra MAUR Madracis auretenra MAUR* thin, fragile, near-parallel, and densely packed MAUR* branches with blunt tips tentacles often expanded by day cream, yellow or yellow-brown (usually to ~ 1.5 m/5 ft) © K. Marks MAUR* *MAUR, formerly called M. mirabilis, was described as a new species by Locke et al., 2007 (reference given on next-to-final slide). © K. Marks Madracis auretenra MAUR clumps many meters/10s of feet wide occur in sheltered habitats © R. Steneck Madracis auretenra MAUR How differs from Porites divaricata polyps are exsert branches are straighter and more closely set yellowish colours larger colonies when fully grown © K. Marks Which is Which? © K. Marks © K. Marks P. divaricata M. auretenra PDIV MAUR Madracis decactis MDEC short, stubby nodules or lumpy crusts* MDEC MDEC small, exsert polyps, each usually with 10 © K. Marks conspicuous septa MDEC green, tan, grey, © K. Marks yellow-brown to dark brown (to ~ 1 m/3 ft) © K. Marks *See Wells, 1973; encrusting colonies with 10 septa/polyp are also called Madracis decactis f. pharensis (Fenner, 1993, 1999) or morphospecies Madracis pharensis (Frade et al., 2010, and citations therein) (references given on next-to-final slide). Madracis decactis MDEC How knobby morph differs from M. auretenra + P. porites: forms stubby knobs, not branches darker colours fully grown colonies are smaller + from P. porites: septa are distinct (can be counted underwater) © K. Marks © M. Vermeij Which is Which? © K. Marks M. decactis P. porites MDEC PPOR Which is Which? © R. Steneck M. auretenra M. decactis MAUR MDEC Madracis senaria MSEN widely spaced polyps, each with about 6 large, exsert MSEN septa (and about 4 small septa) thick crusts that generally follow © M. Vermeij the contours of the substratum, can form conical-round columns MSEN green to orange-brown to dark brown (to ~ 30 cm/1 ft) MSEN © E. Weil Madracis senaria MSEN How differs from encrusting M. decactis (and from M. pharensis f. pharensis sensu Wells 1973): thicker crusts more widely spaced polyps, each with about 6 large septa © M. Vermeij © E. Weil Madracis formosa MFOR most polyps have 8 septa (can be counted underwater) rounded branches with blunt tips MFOR yellow-brown or red-brown to brown; yellowish polyp mouths ( to ~ 60 cm/2 ft) © M. Vermeij MFOR MFOR © M. Vermeij Madracis formosa MFOR How differs from M. decactis polyps usually have 8 septa branching, not nodular, colonies that are larger when fully grown © M. Vermeij © M. Vermeij Madracis carmabi MCAR* polyps have 10 septa ovoid or rounded branches MCAR* often grow in the same plane and may have blunt tips brown with yellow-green polyp mouths © M. Vermeij (to ~ 2 m/6 ft) MCAR* *M. carmabi was described as a new species by Vermeij et al., 2003, and is thought to be a hybrid of M. formosa and either M. decactis or M. pharensis sensu Frade et al., 2010 (references on next-to-final slide). © M. Vermeij Madracis carmabi MCAR How similar to M. formosa thick branches with blunt tips How similar to M. decactis + how differs from M. formosa: polyps have 10 conspicuous septa How differs from M. decactis: branching, not nodular, colonies that are larger when fully grown © M. Vermeij Which is Which? Close-up Close-up © M. Vermeij © M. Vermeij M. carmabi M. formosa MCAR MFOR Oculina diffusa ODIF short, somewhat twisted branches with ODIF large, distinct polyps yellow-brown, or may lack zooxanthellae (to ~ 30 cm/1 ft) © K. Marks ODIF ODIF © C. Rogers © K. Marks Oculina diffusa ODIF How differs from M. auretenra: polyps are larger and protrude more above the skeleton © P. Humann © K. Marks Which is Which? © K. Marks © K. Marks M. auretenra O. diffusa MAUR ODIF Acropora ACRO All species: tiny (axial) polyps at the tips of actively growing branches are colourless (look white) © K. Marks Acropora palmata APAL lateral (radial) polyps are brown or yellow-brown (contain zooxanthellae) © K. Marks Acropora cervicornis ACER Acropora palmata APAL large branches, cylindrical where exposed to waves can form big colonies (to ~ 4m/12 ft) APAL © C. Rogers Acropora palmata APAL branches flatten in calm water © W. Precht © K. Marks Acropora cervicornis ACER long, slender (1-3 cm), round branches ACER (to ~ 3m/10 ft) ACER © C. Rogers © K. Marks Acropora cervicornis ACER can form very large clumps © C. Rogers Acropora prolifera APRO a hybrid of A. palmata and A. cervicornis branches (0.5-2 cm wide) look like “intermediates” between A. palmata APRO and A. cervicornis (to ~ 3-4 m/10-13 ft) APRO Acropora prolifera APRO How the more “fused branch” forms differ from A. palmata: short branches don’t fuse into large thick masses fully grown colonies are smaller APAL APRO Acropora prolifera APRO How the more “shrubby” and “spindly” forms differ from A. cervicornis: branches are shorter, straighter, more densely packed and may be thinner © K. Marks © K. Marks © K. Marks Which is Which? © C. Rogers © K. Marks © C. Rogers A. prolifera A. palmata A. cervicornis APRO APAL ACER Millepora spp. MILL How Millepora differs from the scleractinian stony corals: minute defensive polyps protrude from tiny pores in the colony surfaces © K. Marks Millepora complanata Millepora complanata MCOM upright blades that rise above an encrusting base may have MCOM subdivided tips blades may interconnect to form complex “honeycombs” yellow, tan or yellow brown © K.