''Amphiprion mccullochi'', also known as whitesnout anemonefish or McCulloch's anemonefish, is a species of

anemonefish Clownfish or anemonefish are fishes from the subfamily Amphiprioninae in the family Pomacentridae. Thirty species of clownfish are recognized: one in the genus '' Premnas'', while the remaining are in the genus '' Amphiprion''. In the wild, t ...

found in subtropical waters at

Lord Howe Island Lord Howe Island (; formerly Lord Howe's Island) is an irregularly crescent-shaped volcanic remnant in the Tasman Sea between Australia and New Zealand, part of the Australian state of New South Wales. It lies directly east of mainland P ...

and Norfolk Island.. It was named for Allan McCulloch, a former Curator of Fishes at the

Australian Museum The Australian Museum is a heritage-listed museum at 1 William Street, Sydney central business district, New South Wales, Australia. It is the oldest museum in Australia,Design 5, 2016, p.1 and the fifth oldest natural history museum in the ...

, Sydney. Like all anemonefishes it forms a symbiotic mutualism with sea anemones and is unaffected by the stinging tentacles of the host anemone. It is a

sequential hermaphrodite Sequential hermaphroditism (called dichogamy in botany) is a type of hermaphroditism that occurs in many fish, gastropods, and plants. Sequential hermaphroditism occurs when the individual changes its sex at some point in its life. In particular, ...

with a strict sized based

dominance hierarchy In biology, a dominance hierarchy (formerly and colloquially called a pecking order) is a type of social hierarchy that arises when members of animal social groups interact, creating a ranking system. A dominant higher-ranking individual is so ...

: the female is largest, the breeding male is second largest, and the male non-breeders get progressively smaller as the hierarchy descends. They exhibit

protandry Sequential hermaphroditism (called dichogamy in botany) is a type of hermaphroditism that occurs in many fish, gastropods, and plants. Sequential hermaphroditism occurs when the individual changes its sex at some point in its life. In particular, ...

, meaning the breeding male will change to female if the sole breeding female dies, with the largest non-breeder becomes the breeding male.

Description

''A. mccullochi'' is dark brown with a pale snout, a white bar on each side of the head (but not connected on top of the head) and a pale tail. Juveniles have two white bars and the edge of the pectoral fins is yellow. They have 10 dorsal spines, 2 anal spines, 15-17 dorsal soft rays and 13-14 anal soft rays. They reach a maximum length of .

Color variations

Some anemonefish species have color variations based on geographic location, sex and host anemone. ''A. mccullochi'' does not show any of these variations.

Similar species

''A. mccullochi'' is similar in appearance to '' A. melanopus'' which is distinguished by its reddish chest, belly and dorsal fin, with a yellowish to slightly red tail. The white bars are also connected over the top of the head.

Genetic analysis Genetic analysis is the overall process of studying and researching in fields of science that involve genetics and molecular biology. There are a number of applications that are developed from this research, and these are also considered parts of ...

suggested evolutionary connectivity among samples of ''A. mccullochi'' and ''A. akindynos''. Historical hybridization and introgression in the evolutionary past resulted in a complex mitochondrial DNA structure. There were two evolutionary groups with individuals of both species detected in both, thus the species lacked reciprocal

monophyly In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

. There were no shared haplotypes between species. Image:Amphiprion mccullochi RLS3.jpg, ''A. mccullochi'' (Whitesnout anemonefish) Image:Amphiprion melanopus RLS.jpg, '' A. melanopus'' (Red & Black anemonefish) Image:Amphiprion akindynos RLS.jpg, The genetically related ''A. akindynos'' (Barrier Reef anemonefish)

Distribution and Habitat

''A. mccullochi'' is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

to the south western

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 contin ...

at Lord Howe Island,

Middleton Reef Middleton Reef is a coral reef in the Coral Sea. It is separated by a deep oceanic pass some 47 km wide from nearby Elizabeth Reef, forming part of the Lord Howe Rise underwater plateau. It is around 230 km from Lord Howe Island and ...

Elizabeth Reef Elizabeth Reef, located at is a coral reef in the Coral Sea. The reef is separated by a deep oceanic pass, some 47 km wide, from nearby Middleton Reef, both of which are part of the underwater plateau known as the Lord Howe Rise. It ...

and Norfolk Island.

Host anemones

The relationship between anemonefish and their host sea anemones is not random and instead is highly

nested ''Nested'' is the seventh studio album by Bronx-born singer, songwriter and pianist Laura Nyro, released in 1978 on Columbia Records. Following on from her extensive tour to promote 1976's ''Smile'', which resulted in the 1977 live album '' Seas ...

in structure. ''A. mccullochi'' is highly specialised, being hosted with only 1 species of anemone: *''Entacmaea quadricolor'' Bubble-tip anemone

Conservation status

Anemonefish and their host anemones are found on coral reefs and face similar

environmental issues Environmental issues are effects of human activity on the biophysical environment, most often of which are harmful effects that cause environmental degradation. Environmental protection is the practice of protecting the natural environment on t ...

. Like

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 ...

s, anemone's contain intracellular

endosymbiont An ''endosymbiont'' or ''endobiont'' is any organism that lives within the body or cells of another organism most often, though not always, in a mutualistic relationship. (The term endosymbiosis is from the Greek: ἔνδον ''endon'' "within ...

zooxanthellae Zooxanthellae is a colloquial term for single-celled dinoflagellates that are able to live in symbiosis with diverse marine invertebrates including demosponges, corals, jellyfish, and nudibranchs. Most known zooxanthellae are in the genus ''S ...

, and can suffer from

bleaching Bleach is the generic name for any chemical product that is used industrially or domestically to remove color (whitening) from a fabric or fiber or to clean or to remove stains in a process called bleaching. It often refers specifically, to ...

due to triggers such as increased water temperature or

acidification Acidification may refer to: * Ocean acidification, decrease in the pH of the Earth's oceans * Freshwater acidification, atmospheric depositions and soil leaching of SOx and NOx * Soil acidification, buildup of hydrogen cations, which reduces the ...

. Characteristics known to elevate the risk of extinction are small geographic range, small local population and extreme habitat specialisation. The small geographic range, small local population and extreme habitat specialisation (it only associates with '' Entacmaea quadricolor'') are all characteristics known to elevate the risk of extinction making ''A. mccullochi'' of particular conservation concern. This species was not evaluated in the 2012 release of 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 ...

Etymology

The specific name honours Whitley's colleague, the Australian ichthyologist Allan Riverstone McCulloch (1885-1925) who collected the

type specimen In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralizes th ...

In aquaria

This species has bred in captivity.

References

External links

* * {{Taxonbar, from=Q1852922 Pomacentridae mccullochi Fish of Australia Fish described in 1929