Calyssopora Grischenko & Gordon & Melnik 2018, n. gen.

Calyssopora n. gen.

Type species. Calyssopora volcano n. sp.

Etymology. Latin calyx, cup, chalice, alluding to the calyciform capitulum of the pedunculate colony, plus - pora, a common suffix in bryozoan names. Gender feminine.

Diagnosis. Colony erect, pedunculate, autozooidal peristomes radiating around infundibuliform calyx in single irregular whorl; interior surface of peristome weakly textured to prickled or pustulose. Calyx center with few or many trabeculae delimiting spaces above which develop 1–2 capacious gonozooids lacking smooth floor. Roof of gonozooid with short erect or curved ooeciostome. Ancestrula erect.

Remarks. Like the species of Dartevellopora Gordon & Taylor, 2010, Calyssopora n. gen. produces pedunculate colonies with a capitulum made up of peristomes. Whereas the stem of the type species, Dartevellopora cylindrica (Borg, 1944) lacks apertures, in Dartevellopora neozelanica Gordon & Taylor, 2010 the column is made up of closed peristomes. Further, compared to species of Calyssopora, the skeletal surface of D. neozelanica is glabrous, autozooidal peristomes lack spinules, prickles or pustules on the inner surface, and the floor of the gonozooid is a discrete, smooth and continuous layer. By way of analogy, the floor of the gonozooid in the lichenoporid genus Disporella Gray, 1848 is also discrete and continuous (though not as smooth as in Dartevellopora) while in Patinella Gray, 1848 it is alveolate (Schäfer 1991; as Lichenopora Defrance, 1823).

Colony form in Calyssopora n. gen. is also similar to that in Alyonushka n. gen., the species of which differ in having an excessively and minutely prickled skeletal surface and a discrete incubation-chamber floor.