Lissoclinum perforatum (Giard, 1872)

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 : 158

Lissoclinum perforatum (Giard, 1872)

Fig. 3 F

References and synonymy: Lissoclinum argyllense Lafargue (1968) p. 422; Lissoclinum perforatum (Lafargue 1975) p. 292.

Localities: 2N, 3N.

The colonies are encrusting, of whitish colour. The tunic has a moderate abundance of spicules. These are of ca. 40 µm and have a characteristic shape, with flabellate rays.

The common cavity of the colony is wide, with zooids included in strands of tunic. The branchial sacs are widely open to the common cavity, with wing-shaped thoracic organs in the middle part. The digestive system is small and not twisted (i.e., it has the stomach in ventral position). There were no gonads or larvae.

Remarks. this species has appeared on artificial structures and bivalve cultures in the Coquimbo area. Lissoclinum perforatum is an Atlanto-mediterranean species that has been introduced in the western Atlantic (Monniot 1983, Rocha et al. 2005, Rocha and Bonnet 2009, Dias et al. 2013). This is the first finding of this species in the Pacific Ocean, representing a remarkable range expansion.

Figures

FIGURE 3. Didemnid species. Didemnum studeri: A, colonies, B, anterior region of a larva; Polysyncraton trivolutum: C, image of a colony, D, thorax in dorsal (left) and lateral (right) view; E, spicules of Didemnum studeri; F, spicule of Lissoclinum perforatum; G, spicule of Polysyncraton trivolutum. Scale bars: A, 5 cm; B, 0.1 mm; C, 1 cm; D, 0.25 mm; E, 10 µm; F, 5 µm; G, 1 0 µ m.