Granulogorgia Tang, Alderslade & Xu, 2025

Genus Granulogorgia Tang, Alderslade & Xu , gen. nov.

urn:lsid:zoobank.org:act:17A1D143-481D-46AE-B1EB-B42E0424FD47

Diagnosis. Colony planar with proteinaceous axis possessing a hollow, cross-chambered core. Polyps retractile into volcano-shaped calyces. Polyp armature consisting of large spindles arranged as collaret and points. The tentacles contain flattened rods and spindles, sometimes curved. Sclerites in calyx are elongate plates or scales, often tapering at one or both ends, with irregularly lobed margins and notably large warts both of which are ornamented with granules. The coenenchyme contains warty rods and spindles together with irregular branched forms.

Type species. Granulogorgia amoebosquama gen. et sp. nov. by monotypy.

Etymology. Part of the Latin granulum, in reference to the granule-ornamented warts and lobes on the sclerites, combined with the commonly used octocoral suffix - gorgia. Gender feminine.

Remarks. There is a species of Astromuricea sensu lato, and one of Placogorgia sensu lato that have similarities to Granulogorgia amoebosquama gen. et sp. nov., and these are discussed in the Remarks of the species description, below. At the generic level it would seem prudent to compare the new taxon with Discogorgia Kükenthal, 1919 when the description of D. erythraeensis Stiasny, 1938 is considered, since Stiasny’s Fig. C depicts oval to elongate scales with heavily indented edges. However, Grasshoff’s (2000: 65‒67) redescription of the holotype clearly shows inaccuracies in Stiasny’s own representation of the sclerites: users of Stiasny’s works should constantly bear this in mind, such deficiencies in his publications. As seen in Discogorgia campanulifera ( Nutting, 1910) , the type of the genus, the scales or plates are also quite different to those found in Granulogorgia gen. nov. Additionally, they cover the whole surface of the calyces and coenenchyme.

It is worth remarking that the transfer of D. erythraeensis to Pseudoparacis Matsumoto & van Ofwegen, 2023 by those same authors would appear to be unsupported. The authors’ definition of the genus includes “Calycular sclerites are thornscales. Points with spindles with upper end spiny and lower end tuberculate. Collaret with bent spindles, more tuberculate in the middle part. Tentacles with rods.” Grasshoff’s description, however, shows that D. erythraeensis does not have sclerites in the tentacles (Stiasny did not record any, either), the calicular sclerites do not include thornscales, and the tips of the point sclerites are slender and heavily or sparsely warted, but not obviously spined. The sclerites of Pseudoparacis are mostly plates, but they occur all over the colony surface, and are very thick. The borders are more-or-less entire, but there are some sclerites with irregular edges. Those in the coenenchyme often have projections on the outer face. Additionally, the calyces also contain well developed thornscales and large point sclerites with a spiny distal portion. It should be noted that these characters match those of Lepidomuricea Kükenthal, 1919 : compare the illustration of Lepidomuricea ramosa ( Thomson & Henderson, 1906: pl. V, Figs 1,4) with that of Pseudoparacis spinifera ( Nutting, 1912) given by Matsumoto & van Ofwegen (2023: Fig. 36A). In our phylogenetic analysis, Lepidomuricea sp. DQ302857 View Materials and Pseudoparacis spinifera (the type species of Pseudoparacis ) showed a genetic distance for mtMutS of 0.14%, indicating they may be congeneric and warrant further review.