The leopard blenny (Exallias brevis) also known as the pink-spotted blenny, shortbodied blenny and honeycomb blenny is a fish full of character. When first approached underwater they will often dive for the nearest hole or crevice in their rather ungainly swimming fashion which looks more like series of hops than a swim. Once the leopard blenny is in it’s hiding spot it will poke its head out and then sometimes, it will start watching you.
The leopard blenny has a proportionally large head which tapers down to a small tail. The skin is not smooth with a series of dimples, most likely to aid with camouflage. Females are white with a series of brown colored spots situated in the dimples. Spots are darker around the head and upper body and lighter going back towards the tail. The pectoral, dorsal and caudal fins are yellow in color. Males have similar brown spots on the head but have red or pink spots from behind the gills onto the tail as can be seen above. The dorsal and caudal fins are also either red or pink in color. The pattern and coloration camouflages the leopard blenny remarkably well on some porites corals.
Leopard blennies have a fringe of cirri running across the body just behind the eyes with a tentacle above each eye and two below the eyes, nearer to the mouth. The eyes are rather large with a series of dark brown dots, similar size to the pupil, around the edge of the eye. The mouth of the leopard blenny has a series of comb-like protuberances on the upper jaw which are used for scraping their food. The fish grows to roughly 14 cm (5.5″) in length.
The leopard blenny occurs throughout the Indo-Pacific, from the East African Coast and Red Sea, to Hawai, and is found mainly on coral reefs, always with a hiding place or hole close by. At night they are often found sleeping in staghorn corals.
They feed mainly on coral which include; Acropora, Porites, Millepora and others. It eats by using its lower jaw to bite onto coral while the upper jaw (with the comb like appendages) scrapes coral polyps into its mouth. The fish has been observed to cause localized bleaching during its feeding activities creating white spotted markings on the coral.
Not much is known of the reproduction, however, the male has been reported to graze heavily on an area of coral and eggs are usually laid on this area. The male in the image below on the left was seen on Fern reef in Dar es Salaam Tanzania. It was swimming in circles around an acropora coral and darting into the same spot in the coral. On closer inspection there was a female in the coral. The male was swimming in a circle, darting in next to the female, darting out and in the four or five minutes that I was able to observe it, it must have done this 20 times. Even my proximity did not stop it from swimming the circle. As I swam away to carch up with the rest of the dive it was still repeating its fast circular swim. In all probability this was mating behaviour.
Because their diet comprises of exclusively of coral polyps this fish should not be kept in an aquarium unless the aquarist has access to continual supplies of live corals. There are reports that some specimens can be switched onto other foods but they then require feeding three times a day. Note that they also give off a slime when stressed and this could create problems in an aquarium.
LEOPARD BLENNY CLASSIFICATION
Feeding activity by the blenny Exallias brevis causes multifocal bleaching in corals: Comment on Zvuloni et al. (2011) Bruce A. Carlson http://www.int-res.com/articles/meps_oa/m463p297.pdf
Dianne J. Bray, 2011, Leopard Blenny, Exallias brevis, in Fishes of Australia, accessed 06 Nov 2014, http://www.fishesofaustralia.net.au/home/species/1911