''Acropora humilis'', also known as finger coral, is a species of
acroporid 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 ...
found in the
Gulf of Aden
The Gulf of Aden ( ar, خليج عدن, so, Gacanka Cadmeed 𐒅𐒖𐒐𐒕𐒌 𐒋𐒖𐒆𐒗𐒒) is a deepwater gulf of the Indian Ocean between Yemen to the north, the Arabian Sea to the east, Djibouti to the west, and the Guardafui Channe ...
, the
Red Sea
The Red Sea ( ar, البحر الأحمر - بحر القلزم, translit=Modern: al-Baḥr al-ʾAḥmar, Medieval: Baḥr al-Qulzum; or ; Coptic: ⲫⲓⲟⲙ ⲛ̀ϩⲁϩ ''Phiom Enhah'' or ⲫⲓⲟⲙ ⲛ̀ϣⲁⲣⲓ ''Phiom ǹšari''; T ...
, the northern and southwestern Indian Ocean, Australia, the central
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 ...
, Japan, southeast Asia, the
East China Sea
The East China Sea is an arm of the Western Pacific Ocean, located directly offshore from East China. It covers an area of roughly . The sea’s northern extension between mainland China and the Korean Peninsula is the Yellow Sea, separated b ...
, the central and western Pacific Ocean, the
Johnston Atoll
Johnston Atoll is an Unincorporated territories of the United States, unincorporated territory of the United States, currently administered by the United States Fish and Wildlife Service (USFWS). Johnston Atoll is a National Wildlife Refuge and ...
and the northwestern
Hawaiian Islands
The Hawaiian Islands ( haw, Nā Mokupuni o Hawai‘i) are an archipelago of eight major islands, several atolls, and numerous smaller islets in the North Pacific Ocean, extending some from the island of Hawaii in the south to northernmost Kur ...
. It also occurs in the
Raja Ampat Islands,
Mariana Islands
The Mariana Islands (; also the Marianas; in Chamorro: ''Manislan Mariånas'') are a crescent-shaped archipelago comprising the summits of fifteen longitudinally oriented, mostly dormant volcanic mountains in the northwestern Pacific Ocean, betw ...
,
Palau
Palau,, officially the Republic of Palau and historically ''Belau'', ''Palaos'' or ''Pelew'', is an island country and microstate in the western Pacific. The nation has approximately 340 islands and connects the western chain of the Caro ...
, and the
Pitcairn Islands
The Pitcairn Islands (; Pitkern: '), officially the Pitcairn, Henderson, Ducie and Oeno Islands, is a group of four volcanic islands in the southern Pacific Ocean that form the sole British Overseas Territory in the Pacific Ocean. The four isl ...
. Occurring in tropical shallow reefs on upper reef flats and slopes at depths of up to , it was described by Dana in 1846.
Description
The species is found in digitate colonies of thick tapering branches. The branches contain one or more axial corallites that are large and dome-shaped, and either incipient axial corallites or branchlets at their bases. Its radial corallites are found in two different diameters, the larger of which are organised in rows. It is mainly cream, blue, brown or purple in colour and the branches have cream or blue tips.
Distribution
It is classed as a Near Threatened species on the
IUCN Red List
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...
and it is believed that its population is decreasing; the species is also listed under Appendix II of CITES. Figures of its population are unknown, but is likely to be threatened by the global reduction of coral reefs, the increase of temperature causing coral bleaching, climate change, human activity, the crown-of-thorns starfish (''Acanthaster planci'') and disease.
It occurs in the Gulf of Aden, the Red Sea, the northern and southwestern Indian Ocean, Australia, the central Indo-Pacific, Japan, southeast Asia, the East China Sea, the central and western Pacific Ocean, the Johnston Atoll and the northwestern Hawaiian Islands. It is present in the Raja Ampat Islands, Mariana Islands, Palau, and the Pitcairn Islands. The species occurs at depths of up to on tropical upper reef flats and slopes and is exported to aquariums.
Taxonomy
It was described as ''Madrepora humilis'' by Dana in 1846.
References
{{Taxonbar, from=Q3940467
Acropora
Corals described in 1846
Near threatened animals