New Insight into the Genus <i>Cladocroce</i> (Porifera, Demospongiae) Based on Morphological and Molecular Data, with the Description of Two New Species

During scientific expeditions in Indonesia and Vietnam, several sponge specimens belonging to the genus <i>Cladocroce</i> were collected. The integration of morphological and molecular analyses, incorporating species delimitation models (ABGD, ASAP, and bPTP) and phylogenetic approaches using three molecular markers (COI, 28S, and 18S–ITS1–5.8S–ITS2–28S), allowed us to discriminate three congeneric species. Two of these species (<i>C. burapha</i> and <i>C. pansinii</i> sp. nov.) were supported by morphological and molecular data, whereas a third species (<i>C. lamellata</i> sp. nov.) was delimited by morphological data only. We formally describe two new species, <i>C</i>. <i>pansinii</i> sp. nov. and <i>C. lamellata</i> sp. nov. <i>C. aculeata</i> is a newly recorded species for Indonesia and the first documented finding after the original description. The re-examination of the type material of <i>C. burapha,</i> and indirectly the molecular approach, allowed us to confirm that <i>C. burapha</i> lives in sympatry with <i>C</i>. <i>pansinii</i> sp. nov. in Vietnam and with <i>C. lamellata</i> in Indonesia. Thanks to these findings, we relocated the paratype of <i>C. burapha</i> to the new species described here, i.e., <i>C. pansinii</i> sp. nov.