Celleporina diota ( Marcus, 1938 )

Ramalho, Laís V., Muricy, Guilherme & Taylor, Paul D., 2011, Taxonomic revision of some lepraliomorph cheilostome bryozoans (Bryozoa: Lepraliomorpha) from Rio de Janeiro State, Brazil, Journal of Natural History 45 (13 - 14), pp. 767-798 : 782-785

Celleporina diota ( Marcus, 1938)

( Figure 7 )

Siniopelta diota Marcus 1938: 48 , pl. 11, fig. 27a–c.

Material examined

Arraial do Cabo: MNRJ-066, Farol beach, Cabo Frio Island , 1 February 2000, collected by L. V. Ramalho, depth 5 m.

Description

Colony massive or nodular, small, white, with irregularly disposed autozooids ( Figure 7A ).

Autozooids semi-erect, elongated with convex frontal walls, imperforate, except for large marginal areolar pores, varying from three to five along each margin, located in furrows ( Figure 7A,B ). Primary orifice longer than wide (121 µm long, range 116–126 µm, by 124 µm, range 116–136 µm), distally rounded and with a shallow U-shaped sinus on proximal border that is wider than deep (29 µm long, range 19–39 µm, by 56 µm, range 48–68 µm); condyles rounded ( Figure 7B ). Peristome becoming elevated in older zooids. Ovicell frontally flattened, closed by zooidal operculum, with pores of various shapes and sizes located between 13 and 16 longitudinal ribs crossed by one or two transverse ribs ( Figure 7A–C ).

Avicularia paired, lateral to orifice, small 65 µm long (range 58–68 µm), located at tip of erect process, directed proximally outwards and upwards; rostrum oval, slightly pointed, indented at distal border, cross-bar complete ( Figure 7A,B ). Additional avicularium sometimes developed distally or proximally of the orifice ( Figure 7A ). Interzooidal avicularia rare (only one observed), large, 204 µm long by 87 µm wide, slipper-shaped, mandible elongate, rounded.

Habitat

Colonies found on Sargassum algae at depths of up to 5 m.

Geographical distribution

Apparently endemic to Brazil: Santos (SP) ( Marcus 1938) and Arraial do Cabo (Farol beach), Rio de Janeiro State (present study).

Remarks

Three Celleporina species are known from Brazil: C. diota , C. costazii ( Audouin, 1826) and C. langei ( Marcus, 1939) (see Marcus 1937, 1938, 1939, 1941; Guimarães and Rosa 1941). Celleporina langei differs in having a weak peristome and orificial avicularia with smooth mandibles. Celleporina diota differs from C. costazii as the latter has more flattened autozooids, smaller frontal and marginal pores, no furrows at the zooidal borders, a sinus of different shape and narrow slits among the ribs of the ovicells.

The species C. souleae Morris, 1979 has a narrower and deeper sinus and an ovicell with up to eight ribs. Celleporina robertsoniae (Canu and Bassler, 1923) has a very much deeper V-shaped sinus, more interzooidal avicularia, smaller marginal pores, and the ovicell is smaller, sometimes triangular and has ribs arising from the centre of the frontal area in rays.

The species most similar to C. diota seems to be C. costata (MacGillivray, 1869) . They differ as C. costata has rounded avicularia, less elevated peristomes, smaller marginal pores and a different sculpture on the ovicells. Marcus (1938) mentioned in his description of C. diota that the avicularia are turned distally and obliquely. In the specimen from Rio de Janeiro, the avicularia have the same shape, but they are directed slightly proximally. The other characteristics are very similar to those mentioned in Marcus’s description. As the only difference between the two species is in the position of the avicularia, the specimen from Rio de Janeiro can be considered to be C. diota .

Celleporina diota was previously recorded from Santos Bay on the São Paulo coast by Marcus (1938). This is the first record of the species from the Rio de Janeiro coast. Like Marcus’s (1938) material, the Rio de Janeiro colonies occur on algae. The range of C. diota along the Brazilian coast may be greater, but because of its apparent preference for algae, it may be overlooked during sampling.

Family PHILODOPORIDAE Gabb and Horn, 1862

Figures

Figure 7. Celleporina diota (Marcus, 1938). (A) General view of the colony; (B) frontal view of the colony showing lateral avicularia, sinus, and ovicells; (C) ovicell detail. Scale bars: A: 300 µm; B: 100 µm; C: 50 µm. MNRJ-066.