''Lobactis'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of plate or mushroom coral in the family

Fungiidae The Fungiidae () are a family of Cnidaria, commonly known as mushroom corals or plate corals. The family contains thirteen extant genera. They range from solitary corals to colonial species. Some genera such as ''Cycloseris'' and ''Fungia'' ar ...

. The genus is monotypic with a single species, ''Lobactis scutaria'', that is found in the

Indo-Pacific 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 ...

region.

Description

''Lobactis scutaria'' is a solitary, non-colonial

coral Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and sec ...

that is free living and not attached to the

seabed The seabed (also known as the seafloor, sea floor, ocean floor, and ocean bottom) is the bottom of the ocean. All floors of the ocean are known as 'seabeds'. The structure of the seabed of the global ocean is governed by plate tectonics. Most of ...

. It is discoid or elongated in shape and can grow to a very large size. The polyp can be up to long ''Fungia scutaria''
Corals of the World online. Retrieved 2011-12-14. and is embedded in a cup shaped hollow known as a

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 ...

, surrounded by calcareous material. Lining this are narrow ribs known as

septa The Southeastern Pennsylvania Transportation Authority (SEPTA) is a regional public transportation authority that operates bus, rapid transit, commuter rail, light rail, and electric trolleybus services for nearly 4 million people in five coun ...

, each having a tall tentacular lobe near its origin in the centre. The septa bear unlobed teeth and further tentacular lobes at intervals where the septa divide. Outside the corallite the ribs continue, now known as costae, bearing rows of tiny spines. The underside of the coral bears a scar resulting from its detachment from the sea bed as a juvenile. The colour varies, often being brown, yellowish or blue with contrasting tentacular lobes. The polyp has a central, slit-like mouth and a small number of short, tapering

tentacle In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work main ...

s.''Fungia'' (mushroom coral)
Reef coral genera of the Western Indian Ocean. Retrieved 2011-12-14.Plate Coral- ''Fungia scutaria''
LHS Virtual Zoo. Retrieved 2011-12-14.

Distribution and habitat

''Lobactis scutaria'' occurs in the Indian Ocean on upper reef slopes especially where there is considerable movement of the water as a result of wave action. It is usually found on sand or beds of coral fragments. It is often associated with other species of ''

Fungia ''Fungia'' is a genus of corals in the family Fungiidae. It is monotypic with the single species ''Fungia fungites'', which is found growing on reefs in the Indo-Pacific. Taxonomy Until 2015, the genus ''Fungia'' had more than 30 species, but b ...

''.

Biology

''Lobactis scutaria'' is a

carnivore A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other sof ...

and catches

plankton Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...

shrimp Shrimp are crustaceans (a form of shellfish) with elongated bodies and a primarily swimming mode of locomotion – most commonly Caridea and Dendrobranchiata of the decapod order, although some crustaceans outside of this order are refer ...

s and

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

with its tentacles. ''Lobactis scutaria'' is a

hermaphrodite In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrate ...

. Eggs and sperm are ejected through the mouth and after fertilisation, develop into

planula A planula is the free-swimming, flattened, ciliated, bilaterally symmetric larval form of various cnidarian species and also in some species of Ctenophores. Some groups of Nemerteans also produce larvae that are very similar to the planula, which ...

larvae which form part of the plankton. After some time these settle on the seabed and undergo

metamorphosis Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some inse ...

. The juveniles attach themselves to the substrate and start feeding, extruding their hard skeletons and growing. At a later stage they become detached from their base and drift around on the sea bed. The polyps feed by day as well as by night.

References

{{Taxonbar, from1=Q18592708, from2=Q3331883 Fungiidae Animals described in 1801 Monotypic cnidarian genera