Cornucopina elongata, 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 : 2678-2679

Cornucopina elongata sp. nov.

( Figure 4B )

Material

Holotype: St. 38 Marion Island (46 ° 58 9 S, 37 ° 59 9 E), 200 m, SAM A27548 .

Description

Colony erect, branching, delicate; each branch made up of two alternating rows of clubshaped zooids. Autozooid with a broad distal portion, 0.5X 0.2 mm, projecting from the axis of the colony, and a slender proximal (axial) portion, 0.7–0.8 mm long; opesia elongate oval, occupying entire frontal surface of distal portion. A long, slender disto-lateral process extends from the frontal side of each autozooid, 0.5 mm long with a maximum thickness of 0.1 mm, bearing a group of two to four articulating, curved, cylindrical spines at the tip (up to 1 mm long) and two spines along its length; two more, short, spines present on the distobasal side of the autozooid. Avicularia sparse, arising from the basal surface of the autozooid, close to the branch axis; very long and slender, abruptly widening distally to resemble a straight coach-horn shape, up to 1 mm long and 0.18 mm across the top, with a terminal, hooked rostrum bearing a short triangular mandible. Ovicell slightly longer than wide, 0.41X 0.40 mm; smoothly calcified, with a frontal lip.

Etymology

Latin, elongatus, prolonged: with reference to the elongate disto-lateral process of the autozooid.

Remarks

The lax, feathery colonies of Cornucopina species are frequently damaged by collection, and taxonomically informative structures, such as avicularia, are readily lost. Thus, it is possible that this new species may possess more than one type of avicularium. In its elongate distolateral process, with two to four terminal spines, and its slender coach horn-shaped avicularia, Cornucopina elongata sp. nov. most resembles C. moluccensis ( Busk, 1884) , recorded from the Malay Archipelago ( Busk 1884; Harmer 1926), off Somalia ( Hasenbank 1932) and from Three Kings Island, northern New Zealand ( Hastings 1943). However, in C. moluccensis the opesia is irregularly triangular in outline, extending disto-laterally along part of the spine-bearing process, quite unlike the oval opesia of C. elongata sp. nov. Further, judging from the figures of Busk (1884) and Harmer (1926), the avicularia of C. moluccensis are proportionately far stouter, and broader distally, than the slender avicularia of C. elongata sp. nov. D’Hondt (1984) listed C. moluccensis from Marion Island, but provided neither a figure nor description of his material.

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.