Cocotropus was first described as a genus in 1858 by the German
naturalistJohann Jakob Kaup as a
monotypic genus, the only species
classified within it being Corythobatus echinatus, which had been described in 1849 by the Danish
zoologistTheodore Cantor from
Penang in Malaysia.[1][2] The genus Cocotropus is classified within the family Aploactinidae in the
suborderScorpaenoidei within the order
Scorpaeniformes,[3] although this family is also treated as a subfamily of the
stonefish family
Synanceiidae[4][5] within the Scorpaenoidei, which in turn is treated as a
superfamily within the order Perciformes.[6] The name of the genus, Cocotropus was not explained by Kaup but may be a compound of coccum, which means "scarlet", and tropus, meaning "manner" or "way", so a "scarlet fish", however C. echinatus is reddish brown rather than scarlet.[7]
Species
There are currently 17 recognized species in this genus:[8][2]
Cocotropus velvetfishes are characterised by the gill membranes not being attached to the isthmus which has fleshy extentions. The anus is just in front of the origin of the
anal fin while the
dorsal fin is continuous. There are parallel ridges between the eyes. The body is covered in velvety scales.[9] The
pelvic fin has a single spine and 3 rays.[10] These are small fishes, the largest is the roughskin scorpionfish (C. monacanthus) which reaches a maximum published
total length of 13.1 cm (5.2 in).[8]
Distribution and habitat
Cocotropus velvetfishes are found in the Indo-Pacific region from the eastern coasts of Africa to
New Caledonia, north to Japan and south to Australia.[2] They are little know fishes most often found sheltering in crevices, underneath coral rubble, or within coral-lined algal areas on either coral or rock reefs.[9]
References
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