Polycarpa gradata, Monniot, 2002

Monniot, Claude, 2002, Stolidobranch ascidians from the tropical western Indian Ocean, Zoological Journal of the Linnean Society 135 (1), pp. 65-120 : 80

publication ID	https://doi.org/ 10.1046/j.1096-3642.2002.00017.x
DOI	https://doi.org/10.5281/zenodo.5490270
persistent identifier	https://treatment.plazi.org/id/436F3F3C-FFDF-FFBE-FF22-F9A1FE541C63
treatment provided by	Carolina
scientific name	Polycarpa gradata
status	sp. nov.

Treatment

POLYCARPA GRADATA View in CoL SP. NOV. (Figs 13,14A)

Material

Holotype: MNHN S1 View Materials POL.B 435, Mozambique: Inhaca Island , 2 m, coll. Berggren, 1986 , Other material examined: Madagascar: Tulear, 50 m, coll. R. Plante, 1970 .

Djibouti, 15 m, coll. C. Monniot, 1996.

Description

In the Mozambican type material ( Fig. 14A View Figure 14 ), six pedunculate individuals arise from a common stolon. The specimen from Djibouti has only two individuals on a common base. A single pedunculate specimen comes from Madagascar.

The largest body reaches 1.5 cm in length on a peduncle of same length and width. The other lobes present either a single body on a narrow peduncle or one body atop a basal part that contains an incompletely developed individual. In all specimens the tunic is corrugated and naked in its anterior part, while some sand and epibionts occur only on the lower tunic. The apical but well-separated siphons do not protrude ( Fig. 14A View Figure 14 ).

The following description is that of the largest individual arising from the upper part of a lobe of the type colony. The tunic is thick, solid but flexible. Removed from the tunic, the body is oval, and the siphons lie opposite a prolongation of the body wall that penetrates a short way into the peduncle.

The body wall is opaque, with an evenly distributed musculature. There is a large oral velum. At its base about 30 long thin tentacles alternate with others that are clearly smaller. The prepharyngeal band curves in a dorsal V where the dorsal tubercle, has a C-shaped slit opening anteriorly. The dorsal lamina is high with a smooth edge. The branchial tissue is thin. There are four round folds on each side, wide and low, carrying uncrowded longitudinal vessels. We counted up to five stigmata in a mesh on the folds. There is an average of two longitudinal vessels between the folds, separated by eight stigmata. The branchial formula is: