Calcinean sponges (Porifera: Calcarea) from the shelf edge of the Great Australian Bight.

This article focuses on the taxonomic characterization and biodiversity assessment of calcareous sponges (subclass Calcinea) from the deep-water regions of the Great Australian Bight (GAB), an area subject to hydrocarbon exploration. Using integrative taxonomy combining morphological and molecular analyses, the study identified 11 calcinean species at depths of 189–283 m, including nine species and two genera new to science, such as Clathrina williamsi, Leucascus boomerang, and Robspongia vociva. The findings reveal a unique and previously undocumented community of calcareous sponges in the GAB, with high species richness concentrated near the continental shelf edge (~200 m depth) and suggest a high degree of endemism. The study also provides revised taxonomic diagnoses for several genera and discusses the phylogenetic relationships within the family Leucettidae and related taxa.