''Tubastraea faulkneri'', common name Orange sun coral, is a species of large-polyp stony corals belonging to the family

Dendrophylliidae Dendrophylliidae is a family of stony corals. Most (but not all) members are azooxanthellate and thus have to capture food with their tentacles instead of relying on photosynthesis to produce their food. The World Register of Marine Species incl ...

. Other common names of this coral are Orange Cup Coral, Sun Coral, Orange Polyp Coral, Rose Sun Coral, Golden Cup Coral, Sun Flower Coral, and Tube Coral.

Etymology

The species has been named ''faulkneri'' by the American paleontologist John West Wells in 1982 in honor of Douglas Faulkner, who collected and illustrated in color the specimen used for the description.

Distribution

This species is mainly present in the

Indo-Pacific Ocean The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the s ...

, in Australian water and from the Philippines to the Galapagos Islands.

Habitat

These large-polyp stony corals usually occurs in areas with a strong water flow and a high nutrient content, not necessarily related to the reef, at depths of 3 to 5 m.

Description

''Tubastraea faulkneri'' is an encrusting coral that can become massive and strongly convex. The

corallite A corallite is the skeletal cup, formed by an individual stony coral polyp, in which the polyp sits and into which it can retract. The cup is composed of aragonite, a crystalline form of calcium carbonate, and is secreted by the polyp. Corallit ...

s of this species are covered with a porous tissue (

coenosteum In corals, the coenosteum is the stony skeletal material secreted by the coenosarc, the layer of living material lying between the corallites (the stony cups in which the polyps sit). The coenosteum is composed of aragonite, a crystalline form of c ...

) with a vermicular appearance. The calices have a diameter of and a depth of . They are spaced of and rise of above the

. The tentacles of the polyps are bright yellow-orange, while the coenosteum and the center of the polyps are deeper orange. The surface of the coenosteum is swollen between calices. They have four cycles of septa, with almost vertical internal margins dropping steeply towards the

columella Lucius Junius Moderatus Columella (, Arabic: ) was a prominent Roman writer on agriculture in the Roman Empire. His in twelve volumes has been completely preserved and forms an important source on Roman agriculture and ancient Roman cuisin ...

.Wells, J. W. 198
Notes on Indo-Pacific Scleractinian Corals. Part 9. New Corals from the Galapagos Islands Pacific Science 36(2):211-219 [216]
/ref> The third cycle of septa barely reaches the edge of the calice and the fourth cycle is weakly developed, often incomplete and irregularly fused in the third cycle. The columella is deep, spongy, and often slightly compressed. This species is rather similar to ''

Tubastraea coccinea Orange cup coral (''Tubastraea coccinea'') belongs to a group of corals known as large-polyp stony corals. This non-reef building coral extends beautiful translucent tentacles at night. ''Tubastraea coccinea'' is heterotrophic and does not conta ...

'', but the latter species lacks of spacing between the corallites and usually they are united only at the base, while in ''T. faulkneri'' there is clearly a space between the polyps.

Biology and behavior

These corals are slow growers and do not contribute to coral reef development ( ahermatypic). Unlike many tropical corals, they are azooxanthellate or non-photosynthetic, meaning that they do not live in symbiosis with

zooxanthellae Zooxanthellae (; zooxanthella) is a colloquial term for single-celled photosynthetic organisms that are able to live in symbiosis with diverse marine invertebrates including corals, jellyfish, demosponges, and nudibranchs. Most known zooxanthell ...

in their tissues, allowing them to grow in complete darkness as long as they can capture enough food. They extend their translucent tentacles during the late evening and the night, while during the day the tentacles are completely withdrawn and also the coenosteum is visible. They usually feed on plankton. Like most

coral Corals are colonial marine invertebrates within the subphylum Anthozoa of the phylum Cnidaria. They typically form compact Colony (biology), colonies of many identical individual polyp (zoology), polyps. Coral species include the important Coral ...

s, ''Tubastraea faulkneri'' reproduce asexually. They are

hermaphrodite A hermaphrodite () is a sexually reproducing organism that produces both male and female gametes. Animal species in which individuals are either male or female are gonochoric, which is the opposite of hermaphroditic. The individuals of many ...

s. Mature gametes are spawned through the mouth. The zygote develops into a planktonic

planula A planula is the free-swimming, flattened, ciliated, bilaterally symmetric larval form of various cnidarian species and also in some species of Ctenophores, which are not related to cnidarians at all. Some groups of Nemerteans also produce larva ...

larva.Sea Life Base
/ref>Ayre, D.J. and Resing, J.M. 1986. Sexual and asexual production of planulae in reef corals, Marine Biology 90: 187-190.

References

{{Taxonbar, from=Q3942622 Dendrophylliidae Animals described in 1982