Culeolus longipedunculatus Vinogradova, 1970

Sanamyan, K. E. & Sanamyan, N. P., 2006, Deep-water ascidians (Tunicata: Ascidiacea) from the northern and western Pacific, Journal of Natural History 40 (5 - 6), pp. 307-344 : 327

Culeolus longipedunculatus Vinogradova, 1970

( Figure 11 )

Culeolus longipedunculatus Vinogradova 1970, p 503 .

Material examined

St. 5621, 5035– 5220 m. One intact specimen marked by Vinogradova as ‘‘ Paratype 1’’.

Description

The body length is 65 mm, the peduncle is long but not complete, an entire peduncle being 132.5 cm long ( Vinogradova 1970). The peduncle is much thinner than in other Culeolus species, being 0.4–0.5 mm in diameter along its whole length. The thin, translucent, whitish test is covered with small hemispherical papillae, some of which have an opaque central granula. The T-shaped postero-ventral crest consists of soft high lamellae. A shorter mid-ventral branch and longer branches extend obliquely along each side from the posteroventral point, and end halfway along the body (far from the atrial siphon). Branchial and atrial orifices are large.

The body wall is thin and translucent except for a thickened area around the branchial and atrial siphons. The body muscles, composed of circular and radial ribbons, form a rather regular network. The circular muscles are crowded around the siphons and form a sphincter under the ring of tentacles, which projects slightly from the body wall. Thin, short and weakly branched branchial tentacles do not protrude outside of the branchial aperture. They are sparse and not numerous, about 15 larger tentacles belonging to the first and the second size orders, with numerous minute slender tentacles irregularly distributed between them. A thick and high prepharyngeal band runs close to the ring of tentacles ventrally and laterally and makes a wide dorsal V around the large dorsal tubercle. The branchial sac has six folds on each side with wide flat intervals between them. The branchial formula is: 2(4)3(8)4(9)5(11)4(10)5(9)2DL3(10)4(9)5(6)4(6)4(7)3(3)2.

Two thick, elongate-oval gonads are on each side of the body. They are not divided into lobes and each is completely covered by a large endocarp. The gonads are in the anterior half of the body, and are parallel to each other and to the longitudinal axis of the body. On the left both gonads are outside of and removed from the open gut loop. The leaf-like lobulated hepatic diverticulae are in two series, one along each side of the stomach. The anus has a slightly undulating margin, but without distinct lobes.

Figures

Figure 11. Culeolus longipedunculatus Vinogradova, 1970. (A) Intact specimen (whole stalk not shown); (B) specimen opened along ventral mid line; branchial sac removed to show gut, gonads, and muscles.