Pseudodistoma arborescens Millar, 1967

Monniot, Françoise, 2012, Some ascidians from the southern coast of Madagascar collected during the “ AtimoVatae ” survey, Zootaxa 3197, pp. 1-42 : 25

Pseudodistoma arborescens Millar, 1967

Pseudodistoma arborescens Millar, 1967: 359 Fig. 1 , Madagascar. Monniot F.1987, New Caledonia.

Stations. TA 28 (MNHN A1 PSE 80). Madagascar, Nosy Be, 28m, 13/07/1992, Laboute col. (MNHN A1 PSE 33) Maldives, 04° 12.94 N –73° 29.04 E, 7m, 23/09/1997, CRRF col. (MNHN A1 PSE 49)

The colonies are made of a bush of lobes erect on sandy stalks, exactly as described and figured by Millar (1967). The bulbous top of a zooid is about 5mm in diameter, the stalk reaches 20mm. In formalin the zooids removed from the tunic are yellow and the testis lobes are often pink. The post-abdomen is particularly long, the ovary is far from the abdomen and the testis vesicles lie behind the ovary but do not reach the extremity of the postabdomen. A long vascular process penetrates into the common peduncle of the colony lobes. No larvae have been found.

The geographic distribution is wide: Madagascar and Maldives in the Indian Ocean and New Caledonia in the south-west Pacific.

Figures

FIGURE 1. Aplidium benhami: A, B, in situ colony (photo P. Laboute); C, colony in formalin.