Acropora sarmentosa

Acropora sarmentosa

Taxonomical systematics

Scientific name

Acropora (Acropora) sarmentosa (Brook, 1892)

Synonyms

Madrepora sarmentosa Brook, 1892

Acropora vermiculata Nemenzo, 1967

Common names

Acropora,

Subgenus

Acropora Oken, 1815

Genus

Acropora Oken, 1815

Family

Acroporidae Verrill, 1902

Suborder

Astrocoeniina Vaughan and Wells, 1943

Order

Scleractinia

Subclass

Zoantharia

Class

Anthozoa

Phylum

Cnidaria

Phylogeny

Closest sibling

Acropora (Acropora) florida (Dana, 1846) (Wallace, 1999)

Species group

florida group (Wallace, 1999)

Clade

SFAHL clade (C) (Wallace, 1999)

Clade origination

SFAHL clade (C) origination appears to coincide with the isolation of the Indo-Pacific Tethys from the Caribbean Tethys after early to mid-Miocene (Wallace, 1999)

Geological history

Fossil record

None

Local ecology

Distribution

Tropical Western Pacific Ocean, Great Barrier Reef, Tropical Eastern Indian Ocean.

Habitat

Shallow exposed upper reef slopes (Veron and Wallace, 1984). Subtidally on reeftops and slopes (Wallace, 1999). Upper reef slopes and lagoons (Veron, 2000).

Biological characteristics

Description

Lobed or cushion-like colonies. Main branches are prostrate. Secondary branches are bottlebrush-like. Dull greenish-grey or brown with pale brown or orange branch tips (Veron, 2000).

 

Polyps have 12 tentacles, 6 entocoelic and 6 exocoelic. The tentacle above the directive septum is elongated. The gastrovascular cavity contains 12 mesentries arranged in 6 bilateral pairs. Pairs 3 and 4 are directive and pairs 5 and 6 are incomplete. (Wallace, 1999).

 

Captive colony showed strong fluorescence. Captive colonies have tentacles extended during the day.

Zooxanthellate

Hermatypic

Associated organisms

Zooxanthellae: dinoflagellate symbionts of the genus Symbiodinium, most likely clade C (Wallace, 1999).

 

Crabs of the genera Tetralia and Tetraloides (Wallace, 1999).

 

Shrimps of the genera Coralliocaris, Jocaste, Philarius and Periclimenes (Wallace, 1999).

 

Barnacles, small fish (e.g. Gobiodon, gastropods and bivalves (Wallace, 1999).

 

Additionally, coral-feeding such as Chaetodon may feed on the polyps (Wallace, 1999).

 

Acropora sarmentosa colony at Cod Hole, Ribbon Reef #10, Queensland, Australia.

 

 

 

A. sarmentosa colony at Osprey Reef in the Coral Sea.

 

 

 

A. sarmentosa colony at Eagle Rock, Ribbon Reef #10, Queensland, Australia.

 

 

 

A. sarmentosa in the aquarium.

 

 

 

Close-up of A. sarmentosa in the aquarium showing corallites with tentacles extended.

 

 

 

Crab (probably Tetralia sp.) in branches. Note this is the actually the discarded exoskeleton of the crab.

 

 

Skeletal structure

Corallum

Hispidose to corymbose. One or two branching units (sometimes more). Main branch usually horizontal or oblique, up to 30 mm in diameter. Branchlets are 6-12 mm in diameter and up to 25 mm in length. In deeper water, the branches may be flattened with branchlets only on upper surface. Growth determinate, or almost so (Wallace, 1999).

Corallites

Axial corallites large and rounded, 3.0-4.0 mm in diameter with calices 1.0-2.0 mm in diameter. Primary septa present up to 3/4 R, secondary septa present up to 1/2 R. Radial corallites 2.6-3.6 mm in diameter with round calices 2.1-2.8 mm in diameter, just touching or slightly separated on branch, tubular appressed. Primary septa present up to 2/3 R, secondary septa present up to 1/4 R. (Veron and Wallace, 1984; Wallace, 1999)

Coenosteum

A dense reticulum with spinules that are laterally flattened or slightly elaborated evenly and sparsely distributed. (Wallace, 1999)

 

Acropora sarmentosa skeleton.

 

Captive care

Lighting

Intense (based on shallow habitat)

Water flow

High with turbulence and/or surges (based on exposed habitat)

Feeding

Zooplankton (e.g. Copepods, Artemia nauplii), particulate organic matter (e.g. finely grated shrimp or mussel meat)

Growth rate

No specific numbers available. Subjective observations suggest the growth rate is medium to fast under ideal conditions.

Diseases and other maladies

"Black band disease" had been reported from A. sarmentosa on the Great Barrier Reef (Dinsdale, 1994 in Wallace, 1999).

 

"White band disease" has not so far been reported in A. sarmentosa not from the Great Barrier Reef, but has been reported for several species in the Philippines (Wallace, 1999)

 

Other maladies may be possible including: Shut-down reaction (SDR), which may be the same as Rapid Tissue Degeneration (RTD) and Bleaching.

 

I have personally lost a colony to SDR/RTD.

Reproduction

Sexual reproduction mode

Broadcast spawner (Wallace, 1999)

Sexes

Hermaphrodite (Wallace, 1999)

Asexual methods

Fragmentation due to storms and other physical disturbances neither frequent nor infrequent (Wallace, 1999). Fragments can be propagated.

References

Veron J.E.N. 2000. Corals of the World - Volumes 1, 2, 3. Australian Institute of Marine Science, Townsville, Australia. 1382pp.

Veron J.E.N. and Wallace C.C. 1984. Scleractinia of Eastern Australia. Part 5 Family Acroporidae. Australian Inst Mar Sci Monogr Ser VI:, . 485pp.

Wallace C.C. 1999. Staghorn Corals of the World : A Revision of the Coral Genus Acropora. CSIRO, Collingwood, Australia. 420pp.