Polycarpa chinensis ( Tokioka, 1967 )

Kott, Patricia, 2008, Ascidiacea (Tunicata) from deep waters of the continental shelf of Western Australia, Journal of Natural History 42 (15 - 16), pp. 1103-1217 : 1200-1201

Polycarpa chinensis ( Tokioka, 1967)

Cnemidocarpa chinensis Tokioka 1967, p. 188 .

Polycarpa chinensis: Kott 1985, p. 157 and synonymy.

Distribution

Previously recorded (see Kott 1985): Western Australia (Dampier Archipelago, Cockburn Sound); Victoria (Bass Strait); Queensland ( Moreton Bay , Gladstone, Mackay, Bowen, Townsville, Nymph I., Temple Bay , Murdoch Point, Murray I.); China (Hsia-men); Vietnam. New records: Western Australia CSIRO SS10 / 05 (Albany, Stn 26, 212 m, 23.11.05, QM G328437 five specimens; Bald I., Stn 35, 200 m, 24.11.05, QM G328053 G328463 ; Jurien Bay , Stn 83, 113 m, 2.12.05, QM G 328170 ; Carnarvon, Stn 124, 100 m, 08.12.05, QM G328146 ) .

Description

Specimens are laterally flattened, the test thin, rigid and brittle with embedded sand and the body wall adheres closely to it. The largest specimen (QM G328146) has roots along the ventral margin and is 2 cm long. It has up to four internal longitudinal vessels on the folds and two to four between the folds. The gut does not form a loop, rather it extends in a gentle arc from the posterior end of the thorax to the sessile atrial aperture about one third of the way down the dorsal surface. The small, rounded stomach at the proximal end of the gut has straight, internal folds. The anus is fringed with 15 rounded scallops. A row of gonads is along the body wall each side of the endostyle. Each gonad consists of eight pairs of male follicles beneath a short oval ovary directed toward the atrial aperture.

Remarks

The relatively few internal longitudinal branchial vessels between and on the low branchial folds, the gut running a more or less straight course, gonads in a line each side of the endostyle together with the general form of the body, its brittle rigid test and the roots that fix it into the substrate are all characteristic of this species. There appears to be some variation in the distribution of scallops around the anal border although it is not considered a sufficient reason to separate the present specimen from Carnarvon from others assigned to this species.

The species appears to be primarily tropical, although its range extending into temperate waters is evident from its occurrence at Bald I. and Bass Strait to the south, and north to the South China Sea.