Ianthella basta seems to have been relatively recently introduced into the Marshalls. Currently this large "Elephant Ear" sponge with colonies sometimes 2m across are a prominent feature of the lagoon bottom, seen often at the bases of southern Kwajalein Atoll lagoon pinnacles and growing conspicuously on shipwrecks at depths of about 25m and deeper. Smaller colonies are common shallower. Yet those of us who personally dove those areas in the late 1960s and through at least the first half of the 1970s can recall none of these highly visible colonies, while at the same time remembering smaller and less flamboyant species in the same areas. I suspect the species may have been introduced, possibly on the bottoms of ships passing through the atoll and stopping at Kwajalein, and it has now become well established.
Created 1 June 2019