Dentatisis Xu, Watling & Xu 2024, gen. nov.

Dentatisis Xu, Watling & Xu, gen. nov. urn:lsid:zoobank.org:act: 9E17621F-5AA4-4B93-BDB4-EAAA9031B2FD Diagnosis. Colony unbranched or irregularly dichotomously branched from the short nodes. Polyps cylindrical with a slightly medial constriction, usually biserially arranged but sometimes irregularly on all sides. Flat rods in tentacles with toothed lateral edges and two rounded and slightly expanded ends. Sclerites various in polyp body wall and coenenchyme, including granulated rods/needles, flat rods and scales. Small rods with irregular conical projections in the pharynx. Type species. Dentatisis bathyalis Xu, Watling & Xu, sp. nov. Etymology: Composition of the Latin prefix dentat- (means dentate and toothed, in reference to the elongate and dentate sclerites in the tentacles) and + isis, the stem group name. Remarks. The new genus Dentatisis is characterized by flat rods in tentacles with toothed lateral edges and two rounded and slightly expanded ends, rods with irregular conical projections in the pharynx, granulated needles and flat rods both present in polyp body wall, which can easily separated the new species from other genera in clade J3. There are two new species found in this genus, including Dentatisis bathyalis sp. nov. and D. projecta sp. nov., as described below. They have obvious differences in morphology, especially the sclerites in polyp body wall and coenenchyme, showing high interspecific morphological differentiation. However, they have similar sclerite forms in the tentacles and pharynx. Moreover, their mtMutS and 28S gene sequences allow them to form their own clade with interspecific differences (see the genetic analysis before).