''Pictichromis diadema'', the bicolor dottyback, diadem dottyback, or purple-top dottyback is a

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 ...

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of the

dottyback The dottybacks are a family, Pseudochromidae, of fishes which were formerly classified in the order Perciformes, but this has been revised and the family is regarded as of uncertain affinities, or ''incertae sedis'' within the Ovalentaria, a cl ...

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

. It is a popular

aquarium An aquarium (plural: ''aquariums'' or ''aquaria'') is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aq ...

fish species.

Distribution

This species is found in rich

coral reef A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups. Co ...

s in the western central

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

, eastern

Malay Peninsula The Malay Peninsula (Malay: ''Semenanjung Tanah Melayu'') is a peninsula in Mainland Southeast Asia. The landmass runs approximately north–south, and at its terminus, it is the southernmost point of the Asian continental mainland. The area ...

, and western

Philippine The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

waters. They are found as close as to the surface and as far down as . They are native in 4 countries, including

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

Malaysia Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

, and

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...

Appearance and anatomy

This species is usually yellow in colour with a magenta stripe running along its back. In the wild, they grow to a reported .

Ecology

Their diet in the wild is only known to consist of

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...

s. These fish are capable of changing their sex. After eggs are laid, the male aerates them by picking them up in his mouth. In the wild, they defend a territory several yards in diameter.

In the aquarium

Pictichromis diadema is the first dottyback to be kept in captivity. They are widely sold for the

trade. A very skittish addition to any aquarium, one should be wary to keep this species with other fish of similar sizes; if the ''Pictichromis diadema'' is the bigger, he will attack them, whereas if he is the smaller, he will hide most of the time.

References

* Gill, A. C. 2004 (3 June) Revision of the Indo-Pacific dottyback fish subfamily Pseudochrominae (Perciformes: Pseudochromidae). Smithiana Monographs No. 1: 1–213, Pls. 1–12.

External links

* diadema Fish described in 1978 {{ray-finned fish-stub