Bryopesanser hebelomaia, Tilbrook, Kevin J., 2012

Tilbrook, Kevin J., 2012, Review of the bryozoan genus Bryopesanser Tilbrook, 2006 (Escharinidae: Cheilostomata) with the description of 11 new species, Zootaxa 3165, pp. 39-63 : 55

Bryopesanser hebelomaia n. sp.

(Figures 38–40, Table 1)

Mastigophora dutertrei var. pes anseris: Thornely 1905 (part): 117.

Material. Holotype (here selected): NHMUK ex 1936.12.30.60B, Sri Lanka, Thornely collection.

Description. Brooding colony consisting of only 8 small autozooids, ca 0.60 x 0.40 mm, irregularly polygonal, distinct, separated by shallow grooves. Frontal shield smooth, slightly convex, evenly perforated with small pores, areolar septular pores at each lateral and proximal angle. Primary orifice rounded D-shaped, as wide as long (ca 0.10 x 0.10 mm, excluding sinus), anter deeply arched, proximal border straight, condyles minutely denticulate, sinus drop-shaped, as wide as long. Oral spines 7, evenly spaced. Proximal peristome present only in brooding zooids. Avicularia originating lateral to most proximal pair of spines, rostra small, with smooth edges, open-ended distally, crossbar complete, distally directed, mandibles fan-shaped. Ovicell hyperstomial, producing a thickened proximal edge, frontal process lacking. Ovicellate zooids with 6 oral spines, the most distal pair incorporated into ovicell. Ancestrula longer than wide, 0.30 x 0.20 mm, with 10 spines, 6 closely spaced distally, 4 widely spaced proximally, opesia occupying almost half of frontal surface.

Etymology. Greek hebe, youthful prime; maia, good mother, alluding to its precociousness in producing ovicells at such a small colony size.

Remarks. Bryopesanser hebelomaia n. sp. is characterised by the details of its primary orifice, with its straight proximal border, minutely denticulate condyles, sinus as wide as long, and the lack of a peristome in all but the brooding zooids. The position and size of the avicularia is also characteristic.

Bryopesanser hebelomaia n. sp. differs from B. pesanseris in the shape of its oral condyles, the size and positioning of the avicularia, and its precocious nature. It differs from B. tonsillorum n. sp. (also part of the Sri Lanka collection examined by Thornely) in both the shape of its oral condyles (those of B. tonsillorum are convex and coarsely denticulate) and the presence of multiporous frontal pores in the latter species.

Distribution. Bryopesanser hebelomaia n. sp. is known only from a single colony found in Sri Lanka.