Patinella sp.

Ramalho, L. V., Muricy, G. & Taylor, P. D., 2009, Cyclostomata (Bryozoa, Stenolaemata) from Rio de Janeiro State, Brazil, Zootaxa 2057, pp. 32-52 : 47-50

Patinella sp.

( Fig. 10A–C)

Material examined. Rio de Janeiro state, Brazil: MNRJ-181, MNRJ-244, 23°47.629’S, 041°42.514’W, 20 July 2004, collector D.C. Savi, depth 341 m.

Description. Colony white, disc-shaped, encrusting, surrounded by basal lamina that is frequently elevated from substratum. Sometimes two or more colonies (?subcolonies) grow as a stack ( Fig. 10A–B). Calcification of outer walls of autozooids and basal lamina with small granules and spinules ( Fig. 10B–C), spinules on basal lamina thorn-like, inclined distally. Autozooids elongate, tubular with circular apertures, forming irregular, radial, non-connate rows diverging from colony centre; autozooids near centre of colony grow vertically, those at periphery more inclined and lower ( Fig. 10B); apertural spines 6–8, long and thin ( Fig. 10C); some apertures with serrated distal edge or with small denticles at different levels, longer on one side than other. Alveoli large, almost same diameter as autozooidal apertures ( Fig. 10B–C). Gonozooid not observed.

Remarks. Marcus (1955) described a new species from Brazil under the name Lichenopora tonica . This is here transferred to Patinella following Gordon & Taylor’s (1997) revision of the type species of Lichenopora which showed it to have a steeply conical colony-form unlike that of the numerous recent species that have been assigned to this genus. In the absence of a brood chamber, the very long apertural spines favour assignment of this species to Patinella rather than to Disporella .

In comparing Marcus’s description and drawings to the material from Rio de Janeiro, P. tonica differs in having prominent radial ridges on the basal lamina, uniserial rows comprising 5–12 connate autozooidal apertures, and no apertural spines. Braga (1968) also mentioned the possible occurrence of P. tonica in the Cabo Frio region but was uncertain about his identification as the material was poor. The Rio de Janeiro material differs from P. radiata ( Audouin, 1826) which has autozooidal apertures arranged in connate, uniserial rows and a basal lamina with radial striations. In Patinella verrucaria ( Linnaeus, 1758) the apertures are bicuspate and the basal lamina is striated.

While this species may be new, the lack of a brood chamber and small sample size dissuade us from introducing a new name.

Ecology. Colonies found on calcareous rock at 341 m depth.

Geographic distribution. Study area : Rio de Janeiro State, Região dos Lagos (23°47.629’S, 041°42.514’W) .