Cave-dwelling calcareous sponges (Porifera: Calcarea) from the Marquesas Islands, French Polynesia

A recent study reveals that the Marquesas Islands, part of French Polynesia and a UNESCO World Heritage Site, harbor a unique diversity of cave-dwelling calcareous sponges. Researchers identified five species, four of which are new to science: Borojevia moana, Bidderia watremezi, Leucascus polynesiensis, and Leucandra cavernicola, alongside the previously known Murrayona phanolepis. Unlike adjacent rocky shores, these sponge assemblages exhibit distinct characteristics, with Leucascus polynesiensis being the sole species found both inside and outside caves in French Polynesia. The study employed morphological and molecular tools (ITS and C-LSU) to analyze sponges collected from semi-dark or dark lava tubes. Notably, M. phanolepis appears to be a widespread cave-dwelling species, potentially representing cryptic diversity. Additionally, aliactine spicules may serve as a synapomorphy in the subclass Calcaronea. The findings suggest that Marquesan caves harbor an underestimated and unique biodiversity of calcareous sponges.

Lopes, M. V., Pérez, T., & Klautau, M. (2024). Cave-dwelling calcareous sponges (Porifera: Calcarea) from the Marquesas Islands, French Polynesia. Zoological Journal of the Linnean Society, 202(3). https://doi.org/10.1093/zoolinnean/zlae138