Distaplia colligans Sluiter, 1932

Turon, Xavier, Cañete, Juan I., Sellanes, Javier, Rocha, Rosana M. & López-Legentil, Susanna, 2016, Ascidian fauna (Tunicata, Ascidiacea) of subantarctic and temperate regions of Chile, Zootaxa 4093 (2), pp. 151-180 : 154

Distaplia colligans Sluiter, 1932

Fig. 2

References and synonymy: Distaplia colligans Millar (1960) p. 77; Kott (1969) p. 32; Sanamyan & Schories (2003) p. 94.

Localities: 1S,2S,3S,6S,9S.

The species forms crusts ca. 5 mm in thickness of a bright yellow colour. Cloacal apertures are slightly raised over the colony surface, but no conspicuous zooid systems are visible. The tunic is soft and free of sand.

The zooids measure up to 3 mm. The atrial aperture is large with an anterior lip. The branchial sac has 4 stigmata rows with about 20 stigmata per half-row. A parastigmatic vessel cuts each row. At least 8 fine longitudinal muscles are counted at each side of the thorax. The abdomen is small, comprising the digestive loop with an elongated stomach whose surface is slightly wrinkled. The gonads lie in the centre of the intestinal loop, comprising several male follicles and a central mass of a few oocytes.

There were larvae in the colonies, apparently free in the tunic. They measure 1–1.5 mm of trunk length and bear an oozooid and three adhesive papillae. The stalks of the papillae had two lateral outgrowths in the ventral papilla and one each in the two dorsal papillae.

Remarks. This species is widely distributed in Antarctic and subantarctic waters (Monniot & Monniot 1983, Schories et al. 2015)

Figures

FIGURE 2. Distaplia colligans. A, image of a colony; B, zooid as seen from the left hand side; C, Thoracic region as seen from the right hand side; D, larva. Scale bars: A, 2 cm; B, C, D, 0.5 mm.