Cystodytes solitus Monniot, 1988

Monniot, Françoise, 2012, Some ascidians from the southern coast of Madagascar collected during the “ AtimoVatae ” survey, Zootaxa 3197, pp. 1-42 : 31

Cystodytes solitus Monniot, 1988

( Figure 25 )

Cystodytes solitus Monniot F, 1988: 223 fig 12 a–c, New Caledonia; Monniot F & Monniot C. 2006: 133 fig. 26B, and synonymy Madagascar, Mauritius.

Stations. TA 35 (MNHN A3 CYS 137). TA 52 (MNHN A3 CYS 138).

Salomon Isl. Bellona, 21° 26.403 S –158° 58.139 E, 6m, 21/04/2002 (MNHN A3 CYS 125) P. Laboute coll.

The colonies form thick crusts with a round edge ( Fig. 25A ,B). The tunic is brown and the surface layer contains small round spicules around the siphon apertures ( Fig. 25 B). The zooids are arranged in circular systems, in which the atrial openings are tightly grouped in the centre. The zooid apertures appear in a dark brown colour. The tunic is opaque and does not let see the calcareous plate-like capsules encasing the zooids. Small spicules, in balls of needles, are scattered between the capsules. The dark brown zooids (in formalin) have the general structure of the genus. A pedunculate brooding pouch ( Fig. 25 C) is appended at the oesophagus level and contains a single brown larva 1.1mm long ( Fig. 25 D).

The characteristic look of this species is due to the abundant didemnid- like spicules at the surface layer of the colony and the dark tips of the siphons ( Fig. 25A ,B). The large dark larva in a pedunculate brooding pouch ascertains the identification which is always difficult in the genus Cystodytes .

Figures

FIGURE 25 A, Cystodytes solitus: A, colony; B, colony surface; C, zooid with incubatory pouch; D, larva. Scale bars C, D = 0; 5 mm.