Three new species of Crambe (Crambeidae: Poecilosclerida: Demospongiae) from the south-eastern Pacific, with a review of morphological characters for the genus

Abstract

Three new species of Crambe are described from the upper and middle-southern coast of Chile, south-east Pacific. Crambe chilensis sp. nov. and C. amarilla sp. nov. are astroclone bearing species, while C. maldonadoi sp. nov. has sphaeroclones as asterose desmas. Morphological characters of Crambe were re-evaluated to consider this unsuspected high diversity of Crambe in the south-east Pacific. The main characters for the distinction of Chilean species as well as of other Crambe species were the live-colour; the shape and size of asterose desmas and (sub)(tylo)styles; the shape, number of categories and size-range of anchorate isochelae; and the presence/absence and dimensions of spined microxeas. An identification key for the Crambe of the world is provided. If astroclone and sphaeroclone desma-bearing species groups would represent two distinct evolutionary lineages, then the south-eastern/eastern Pacific Region would have been occupied by two evolutionary lineages with distinct life histories. The relatively high diversity of Crambe in the Chilean temperate coast, together with its occurrence in New Zealand's Oligocene, is suggestive of a likely wide distribution in Panthalassa, which contrasts to earlier suggestions of wide distribution in the Tethyan Realm only.