Actinocyclus verrucosus Ehrenberg, 1831

Actinocyclus verrucosus has been found at Kwajalein and Enewetak Atolls. At Kwajalein, it seems to prefer seaward reefs in channels and on the top of the reef slope, where it can occasionally be found under rocks feeding on a somewhat shiny brown sponge. It can occasionally be on lagoon reefs and pinnacles. Often it closely resembles the sponge and blends in very well. Hallaxa sp. e467 was also found on the same sponge, suggesting that species could be a smooth form of A. verrucosus. Specimens observed in the Marshalls have ranged up to about 40mm in length. We have also seen specimens in Hawaii.

The gill stalks of A.verrucosus are compact and curl into a small ball shape on the posterior dorsal surface.

This large individual was under a rock on a shallow southern Kwajalein lagoon pinnacle on 26 January 2015.

The one below was under a rock on a shallow lagoon reef on 20 May 2013.

A specimen with an egg mass found under a rock on 29 June 2014.

The small specimen below was making a trail, grazing through a thin light gray sponge.

Created 15 December 2006
Updated 14 August 2015

Return to thumbnails

UnderwaterKwaj home