Acanthopharynx Marine Nematodes (Nematoda, Chromadoria, Desmodoridae) Dwelling in Tropical Demosponges: Integrative Taxonomy with Description of a New Species

In the exploration of meiofauna associated with sponges and corals in shallows Cuba, we investigated nine species (Demospongia), wherein 26 nematode were revealed. Most specimens (50–95% all individuals) sponge samples belonged to family Desmodoridae (order Desmodorida), followed by Chromadoridae Chromadorida). A major part is constituted genus Acanthopharynx. statistical morphometric analysis (principal component multidimensional scaling testing via similarities) revealed two close cohorts that differed size pharynx shape. Molecular genetic analyses (COI, 18S, 28S) also distinguished groups corresponded cohorts. Based on morphometry molecular genetics, larger-sized group was defined as Acanthopharynx micans (Eberth, 1873), while smaller-sized considered A. parva sp. n. light taxonomic review Acanthopharynx, emended generic diagnosis, annotated list ten valid species, from other its peculiar shape (gradually widened cardia), smaller body size, pattern precloacal organs.