Cheiloporidion Cairns, 1983a

Bernal, M. C., Cairns, S. D., Penchaszadeh, P. E. & Lauretta, D., 2021, Stylasterids (Hydrozoa: Stylasteridae) from Mar del Plata submarine canyon and adjacent area (southwestern Atlantic), with a key to the species off Argentina, Zootaxa 4969 (3), pp. 401-452 : 3-5

Genus Cheiloporidion Cairns, 1983a

Type species. Cheiloporidion pulvinatum Cairns, 1983a

Included species. Cheiloporidion pulvinatum

Distribution. SWA off Argentina from Mar del Plata to Tierra del Fuego and Cape Horn. Depth: 642–1137 m (see Cairns 1983a). New record off Mar del Plata, 852–1289 m.

Diagnosis (from Cairns 1983b; changes in bold).

Colonies uniplanar with a strong tendency toward branch anastomosis, producing a network of irregularly shaped fenestrae. Branches elliptical to rectangular in cross section, the greater axis perpendicular to the plane of branching. Branches ridged on both anterior and posterior faces. Coenosteum reticulate, composed of short discontinuous strips, which are smooth or granular and have rounded edges. Dactylopores occur randomly on anterior and lateral branch surfaces; gastropores loosely aligned along lateral edges. Gastro- and dactylopore tubes short, branches compact. Gastropores flush with branch surface; gastrostyles ridged, bearing fused spines. Dactylopores rimmed by two to four vertical platelets, which form a discontinuous collar around the pore; no dactylostyles. Ampullae superficial. Soft parts unknown.