Pocillopora meandrina, common name cauliflower coral, is a species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of coral

Coral

Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...

 occurring in the East Pacific and the Indo-West Pacific. This coral lives in shallow reef environments.

Description

The colonies of P. meandrina can be fairly solid and dome-shaped or branching with areas that are either flattened and ridge-like or fine and convoluted. The colonies are covered by wart-like growths called verrucae. The colour ranges from brown to pink and the polyp

Polyp

A polyp in zoology is one of two forms found in the phylum Cnidaria, the other being the medusa. Polyps are approximately cylindrical in shape and elongated at the axis of the body...

s with their extended tentacle

Tentacle

A tentacle or bothrium is one of usually two or more elongated flexible organs present in animals, especially invertebrates. The term may also refer to the hairs of the leaves of some insectivorous plants. Usually, tentacles are used for feeding, feeling and grasping. Anatomically, they work like...

s are usually visible only at night.

Distribution and habitat

P. meandrina occurs in the Indian and Pacific Oceans and is found across a range of habitats that include exposed reef

Reef

In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water ....

s, protected lagoons and lower reef slopes.

Biology

P. meandrina is a hermaphrodite

Hermaphrodite

In biology, a hermaphrodite is an organism that has reproductive organs normally associated with both male and female sexes.Many taxonomic groups of animals do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which both...

 and each polyp contains four sets of male and four sets of female gonad

Gonad

The gonad is the organ that makes gametes. The gonads in males are the testes and the gonads in females are the ovaries. The product, gametes, are haploid germ cells. For example, spermatozoon and egg cells are gametes...

s. The larva

Larva

A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...

e develop inside the body of the polyp and are not expelled into the water until they are mature. They remain free swimming for a number of weeks before settling and starting to build a hard matrix. The polyps can also reproduce asexually

Asexual reproduction

Asexual reproduction is a mode of reproduction by which offspring arise from a single parent, and inherit the genes of that parent only, it is reproduction which does not involve meiosis, ploidy reduction, or fertilization. A more stringent definition is agamogenesis which is reproduction without...

 by fragmentation.

The polyps feed by capturing tiny prey

Predation

In ecology, predation describes a biological interaction where a predator feeds on its prey . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption...

 with their tentacles. They also contain zooxanthella

Zooxanthella

Zooxanthellae are flagellate protozoa that are golden-brown intracellular endosymbionts of various marine animals and protozoa, especially anthozoans such as the scleractinian corals and the tropical sea anemone, Aiptasia....

e, microscopic algae

Algae

Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...

, which are able to photosynthesise

Photosynthesis

Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...

. These symbionts

Symbiosis

Symbiosis is close and often long-term interaction between different biological species. In 1877 Bennett used the word symbiosis to describe the mutualistic relationship in lichens...

produce energy-rich compounds which the polyps metabolise while the rigid structure of the shallow water coral provides a stable, well-lit, protective environment for the algae to flourish.

External links

• Information including a map of distribution of the species http://www2.aims.gov.au/coralsearch/html/301-400/Species%20pages/309.htm
• Aquarium information about how much light various coral species need. Includes a detailed close-up view http://www.advancedaquarist.com/2007/3/aafeature1/view
• ARKive: Pocillopora meandrina http://www.arkive.org/cauliflower-coral/pocillopora-meandrina