Cornucopina antlera, Branch & Hayward, 2005

Branch, M. L. & Hayward, P. J., 2005, New species of cheilostomatous Bryozoa from subantarctic Marion and Prince Edward Islands, Journal of Natural History 39 (29), pp. 2671-2704 : 2676-2678

Cornucopina antlera sp. nov.

( Figure 4A )

Material

Holotype: St. 42 Marion Island (46 ° 32 9 S, 37 ° 51 9 E), 510 m, SAM A27531 . Paratype: St. 38 Marion Island (46 ° 58 9 S, 37 ° 59 9 E), 200 m, SAM A27545 .

Other material. St. 45 Marion Island (47 ° 00 9 S, 37 ° 55 9 E), 420–540 m, SAM A27532 .

Description

Colony erect, branching, delicate; made up of two alternating rows of club-shaped zooids. Autozooids with broad distal portion, 0.4–0.55X 0.25 mm, projecting from the branch axis, and a slender, proximal (axial) portion 0.8–1.0 mm long; opesia elongate-oval, occupying two-thirds of frontal surface of distal portion. Four to five curved, cylindrical spines spaced along the disto-basal wall of the autozooid, up to 1 mm long, and two or more spines on the lateral, axial side of the autozooid; one shorter, proximo-lateral spine. A short, pedunculate avicularium present, fronto-lateral in position, close to the border of the opesia; up to 0.2 mm long and 0.12 mm across the top with hooked, triangular rostrum. Ovicell not observed.

Etymology

Named with reference to the disposition of the disto-basal spines of the autozooid.

Remarks

Cornucopina antlera sp. nov. is characterized by the combination of a short frontal avicularium, the lack of a disto-lateral process and the antler-like arrangement of the spines. Several other species of Cornucopina are known in which the spines arise directly from the disto-basal wall of the autozooid, rather than from an elongate dorso-lateral process. Cornucopina antlera may be distinguished from all of them by its short, oval opesia, which does not extend close to the colony axis, and in its small, fronto-laterally situated avicularia. The samples were obtained from depths of 200–540 m; that from St. 45 lacked avicularia.

Figures

Figure 4. (A) Cornucopina antlera sp. nov., SAM A27531, part of the colony showing autozooids and frontal avicularia, X40; (B) Cornucopina elongata sp. nov., SAM A27548, part of the colony showing autozooids, ovicelled autozooid and long avicularium, X40; (C) Cornucopina bryonyae sp. nov., SAM A27547, part of the colony showing autozooids, ovicelled autozooid and three types of avicularia, X40.