Cnemidocarpa bathyphila Millar, 1955

Sanamyan, K. E. & Sanamyan, N. P., 2002, Deep-water ascidians from the south-western Atlantic (RV Dmitry Mendeleev, cruise 43 and Academic Kurchatov, cruise 11), Journal of Natural History 36 (3), pp. 305-359 : 339-340

Cnemidocarpa bathyphila Millar, 1955

(®gure 21)

Cnemidocarpa bathyphila Millar, 1955: 228 (part); Monniot and Monniot, 1973: 430; 1985b: 28; Monniot et al., 1976: 1190. Monniot, 1997: 21.

Cnemidocarpa sp. Monniot and Monniot, 1977a: 702.

Styela bathyphila: Kott, 1971: 52 .

Styela sericata Millar, 1959: 196 (part).

Material examined. St. 4104, 5110±5120 m, two specimens.

Description. The globular specimens are 5 and 7 mm in diameter. The body is covered by relatively thick hairs, with a naked area only around and between the apertures. About 24 tentacles of two or three size ranges arise from a high velum. There is an atrial velum with a few thin and short tentacles on its edge. Unlike in Cnemidocarpa bythia , described below, we did not ®nd any tentacles or papillae on the test lining the siphons. The prepharyngeal band has two lamellae and forms a shallow wide V around the small dorsal tubercle, which has a transverse slit. The neural ganglion is just posterior, and close to the dorsal tubercle. A high, plainedged, dorsal lamina is displaced to the left and somewhat removed from the closest longitudinal vessel on the right side of the branchial sac. Transverse branchial vessels connecting this vessel and the dorsal lamina are raised into laminar expansions, but there is no inverted fold, which is present in some deep-water Styelidae . The branchial sac has three high folds on each side, of which the most dorsal are highest, and the fourth, most ventral, fold is indicated by a cluster of about four longitudinal vessels. It is di cult to count the number of vessels on and between the folds, the approximat e formula is: E3(3)1(10)2(10)3(17)6DL3(10)4(9)5 (8)2(4)2E.

The stomach has eight to ten wide longitudinal folds and a large caecum. The anal margin is smooth. One gonad is on each side of the body. Their shape is diOEerent in the two specimens. One has a long cylindrical gonad of Cnemidocarpa - type, but in the other specimen the testis follicles are greatly developed and are not only between the ovary and the body wall, but also form clusters on the sides of the ovary (®gure 21B). In both cases the oviduct is long, and male and female openings are close to each other. Three large endocarps are present on each side of the body, one anterior and two posterior to the gonad. On the left the most posterior endocarp is in the gut loop.

Remarks. The presence of an endocarp in the gut loop, ®rst recognized by Kott (1971), is a stable feature of this species, although it was overlooked in several previous descriptions (see Monniot and Monniot, 1985b). Other distinguishing characters are long oviducts, one or two endocarps on the sides of the gonads and well-developed branchial folds.

The species is widely distributed in the Atlantic and Indian Oceans, and has also been recorded from the south-west Paci®c.