First fossil sponge from Antarctica and its palaeobiogeographical significance
Laocoetis piserai n. sp. (Hexactinellida, Porifera) from the mid-Cretaceous (i.e., Albian–Cenomanian) of James Ross Island is the first record of a fossil sponge from Antarctica. This new occurrence of a formerly widespread genus was restricted to relatively deep waters on the margins of an active volcanic arc. Its occurrence in Antarctica is further evidence that the genus Laocoetis underwent a dramatic reduction in its geographic range through the Cenozoic. The only living species of the genus at the present day is Laocoetis perion from Madagascar.