dcsimg

Description

provided by NMNH Antarctic Invertebrates

"Cellarinella anomala sp. nov.

(Plate I, D; II, A-B)

MATERIAL.- Holotype: BMNH 1990.12.13.3, Discovery Stn. WS42; paratypes : BMNH 1990.12.13.4, Discovery Stn. WS42.

DESCRIPTION

Colony erect, with flat, curved or irregularly twisted branches, dividing irregularly to give broad lobes, or narrow strap-like rami; typically narrow at the base, rarely exceeding 6 mm wide, but tending to broaden abruptly to 20 mm or more, and then to divide into a number of Unequal rami. Basal attachment unknown. Autozooid boundaries obliterated in earliest ontogeny by reticulate frontal calcification; the colony surface appearing uniform, regularly Perforated by deep, angular pits, only the apertures marking the position of each autozooid. At the base of the colony all autozooid apertures are obscured by thick, uniformly reticulate calcification. Autozooid aperture wider than long, more or less semicircular, with a smooth, transverse proximal oral shelf; at the growing edge, before the completion of the aperture rim, a broad distal oral shelf may be seen, but there is no internal avicularium. Most autozooids with a single frontal avicularium, proximal to aperture, the rostrum oval, slightly acute to frontal plane and directed proximo-laterally. In a minority of autozooids a second, larger avicularium may be present, lodged within the proximal edge of the aperture, transversely orientated, with a curved, sharply hooked rostrum. Ovicell longer than wide, imperforate, but becoming submerged in reticulate calcification; brooding autozooids may be recognised by a thickened, projecting, proximal apertural lip, which may incorporate, on one or both sides a small, distally directed avicularium, with hooked rostrum." (Hayward and Ryland, 1991: 243-4)

Measurements (mm)

n

z

s.d.

Aperture length

20

0.10

± 0.09

Aperture width

20

0.22

± 0.01

Frontal avic. length

20

0.14

± 0.008

Apertural avic. Length

10

0.24

± 0.02