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Coral Id American Samoa

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CORAL IDENTIFICATION

AMERICAN SAMOAChuck Birkeland, University of Hawaii, Zoology Dept. November 2001Phylum Cnidaria (or Coelenterata which once included Ctenophora) Class Hydrozoa (two of the orders produce solid calcareous skeletons and are called hydrocorals) - no mesenteries, no septa, no stomodeum, tiny polyps Order Milleporina (fire corals) 1 genus; 10 - 15 species With zooxanthellae, grow out in the open Only hermatypic corals with complex life cycle; sex in medusa stage Medusa stage buds in internal chambers, medusa sexual stage. Dimorphism: gastrozooids for feeding, dactylozooids for defending. Millepora dichotoma - colonies branching, usually in one plane, with flattened stems fused into reticular patterned plates Millepora platyphylla - extensive encrusting or submassive base from which solid upright plates develop Millepora tuberosa - encrusting with irregular lumpy or nodular surface; looks like lavender red crustose coralline algae Order Stylasterina Without zooxanthellae, grow under overhangs or in crevices or caves. Brood larvae. No medusa stage. Stylaster gracilis - Arborescent with fine branches growing in one plane. Dimorphism, one feeding polyp surrounded by a ring of defending polyps. Distichopora gracilis - Arborescent with flattened, blunt-ended, non-anastomosing branches of uniform width growing in one plane. Feeding polyps in a row, with a row of defending polyps on both sides. Class Scyphozoa (large medusa, small polyp [often longer lived]) Stephanocyphus, white or green, hidden in algal turf 1

Class Cubozoa (large medusa, small polyp [often longer lived] Class Anthozoa No medusa stage. Mesenteries allow polyps to grow large by increasing surface areas. Mesenteries contain mesoglea. Septa present. Mesenteries location of gonads, contractile muscles. Chord-like structure at the edge becomes free at the bottom and become acontia and mesenterial filament. Subclass Octocorallia (= Alcyonaria) Pinnate tentacles; 8 tentacles Order Coenothecalia Heliopora coerulea - blue coral Order Pennatulacea (one main-frame polyp, in sand) Order Alcyonacea Suborder Stolonifera - runners that bud polyps Clavularia - field of grey ferns Suborder Telestacea - polyps bud side-branch polyps Tubipora musica - organ-pipe coral Suborder Alcyoniina - leathery coenenchyme Family Alcyoniidae - leathery, rubbery, massive Sinularia - one kind of polyp, all sorts of arms and ridges Lobophytum - two kinds of polyp, all sorts of arms and ridges Sarcophyton - two kinds of polyp, flat mushroom Cladiella - cauliflower ghost corals, one kind of black pepper polyp 2

Family Nidaliidae (Siphonogorgiidae) Most spicules; spicule-supported walls; water-filled stalks; arborescent Siphonogorgia - fans with no supporting skeletal framework Chironephthya - look like desiccated or deflated fans with dense spicules Family Nephtheidae Large and conspicuous spicules; widened base; arborescent, stalks and capitulum (usually) Azooxanthellate - brilliant colors Dendronephthya - easily see white spicules in the tissues; polyps brilliantly colored Scleronephthya - solid bright colors; looks like made of modeling clay Zooxanthellate - generally grey-brown Stereonephthya - scratchy tree Nephthya - dull brown or grey tree Litophyton - slimy tree Lemnalia - leathery tree Paralemnalia - fingers up from a pad Family Xeniidae Stalk and capitulum; reduced spicules, feels soft Xenia - pulsating polyps Suborder Scleraxonia mats, carpets, and columns Suborder Holaxonia - scleroprotein axial skeleton plus CaCO3 3

gorgonians

Subclass Hexacorallia (= Zoantharia) Order Actiniaria Sea anemones; 1000+ species Order Zoanthidea Colonial or clonal; zooxanthellate; polyp diameter 0.5 to 2 cm; alternating up/down tentacles; often trumpet shaped; may incorporate sand Order Corallimorpharia Flat, wide oral disks, short polyp; short tentacles arranged in radiating rows; clonal aggregation; 3 to 10 cm. Order Antipatharia Six (6) simple tentacles (not octocorals); cannot be withdrawn; no additional rhind Order Ceriantharia Burrowing in soft sediment; has a parchment tube; 2 cycles of tentacles, inner and outer [Order Ptychodactiaria - Arctic and Antarctic deep water] Order Scleractinia

SCLERACTINIATriassic; families Mesozoic 6 suborders; 11 families of strictly tropical, zooxanthellate, reef-building species; 5 additional families mix of zooxanthellate and non-zooxanthellate species; 7 families entirely nonzooxanthellate (= 23 families total)

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Suborder Astrocoeniina No intermediates with other suborders since first found in Triassic

AstrocoeniidaeStylocoeniella Little pillar with each calice Stylocoeniella armata - tucked away, small (usually < 5 cm), green

PocilloporidaeArborescent, small plocoid calices Pocillopora Bushy or cauliflower colonies characterized by wart-like clumps of polyps called verrucae Pocillopora damicornis - verrucae are essentially the branches; numerous slender crooked branches with numerous short twig-like secondary stems along their length Pocillopora danae - the verrucae are distinct and cover bulbous branches Pocillopora meandrina - small uniform verrucae; meandering flabellate branches Pocillopora verrucosa - permanently colored red-brown stalks; verrucae irregular in size; branches have an upright form Pocillopora eydouxi - colony consists of stout, latterally flattened columns Stylophora Stylophora mordax - thick, blunt-ended branches; corallites immersed, hooded with rasplike hoods Seriatopora Seriatopora hystrix - branches taper to a point; corallites in neat rows

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Acroporidae(Field characters are site-specific.) Light spongy skeletons; very small to moderate calices; poorly developed septa; reduced or lost columella; widely separated small plocoid calices; costae often absent Four genera, greatest number of species AcroporaSUBGENUS ISOPORA

More than one axial corallite per branch; thick cuneiform (wedge-shaped) branches; can be encrusting Reproduces sexually by internal fertilization, larvae brooded before release Acropora palifera - thick branches as ridges or columns with multiple axial corallites, sometimes encrusting Acropora cuneata - rounded clumps, cuneiform branching can form blade-like branches perpendicular to the reef front, can be encrusting Acropora crateriformis - circular encrusting (up to 80 cm) brown cow piesSUBGENUS ACROPORA

Single axial corallite forms axis of branch, opening at the tip. Nearly all are branching. The spongy skeleton and division of function of corallites into two types allows for rapid organized growth. Reproduces by spawning [Acropora austera group] Acropora austera colony is very rugged and rough irregular thicket; thick branches with large bulbous tightly packed radial corallites [Acropora humilis group] 6

Sturdy, digitate or corymbose, terete or conical; size determine by axial corallite; very shallow surf zone, reef flat or edge; one or two sizes of radial corallites Acropora humilis - Usually terete (to conical); generally one size of radial corallites; big flat conspicuous white or blue tip axial polyp Acropora gemmifera - just like A. humilis, but with immersed as well as larger radial corallites, i.e., 2 sizes Acropora monticulosa - broad, low, conical; terminal polyp smaller than A. humilis or A. gemmifera, about same size as radial polyps; corallites increase in size down the branches; bases often look hexagonal Acropora samoensis - not so sturdy, caespitose-corymbose, frequent branching, branches terete; radial corallites separate, not touching; cream or pale brown; very rough, radial corallites protrude a lot, especially near the base; found deeper, to 15 m Acropora digitifera - digitate-corymbose, branches short and thin relative to others in group; corallites close to branches; usually blue tips; large rims on corallite [Acropora nasuta group] Corallites nariform, even-sized or in 2 sizes, corymbose colonies Acropora nasuta - branches almost as thick as fingers, fairly stout, white coenosteum Acropora cerealis - thinner branches than A. nasuta; spiny appearance, extended outer radial corallite walls; white coenosteum, usually blue tips, surrounded by pink; plates side-attached or small tables Acropora secale - long tubular and short nariform corallites; purple tip and yellow branch, same color as A. valida but thicker Acropora valida - small rounded corymbose or thick tables (same color as A. secale but thinner) Acropora lutkeni (= A. ocellata) - radial corallites are rounded and smooth; irregular corallites; sturdy branches, irregular growth so no two colonies alike; corymbose to irregular caespitose

[Acropora verweyi group] 7

Radial corallites evenly sized and shaped, with large round openings Acropora verweyi - whitish or creamy brown, usually with orange axial corallites; bulbous rounded club-shaped corallites; very long protruding purple or blue tip axial polyp; low clumps or patches, more flat-topped than rounded Acropora glauca - stout looking; radial corallites evenly shaped, evenly arranges, just touching; radial corallites appressed with large round tubular openings; corymbose or anastomizing corymbose; like rocky shores [Acropora divaricata group] Radial corallites contribute strongly to branch diameter; branches usually well-spaced and evenly arranged, which tends to produce symmetrical colonies; determinate growth Acropora divaricata - break off a branch and see scribble marks; divergent branching pattern within a bracket or rounded arborescent table, radial corallites are tubular, slight nariform, and tending towards appressed Acropora clathrata - large tables, very flat surface; anastomosing branches; large spaces, able to stick fingers in spaces [Acropora muricata group] Open branches, very arborescent Acropora muricata (= Acropora formosa) - narrow tubular radial corallites close together; going every which way; thickets; rel