Styela clava Herdman, 1881

Kott, Patricia, 2008, Ascidiacea (Tunicata) from deep waters of the continental shelf of Western Australia, Journal of Natural History 42 (15 - 16), pp. 1103-1217 : 1196

Styela clava Herdman, 1881

Styela clava Herdman 1881, p. 70 . Kott 1985, p. 115 and synonymy. Hewitt et al. 2002. NBII National Biological Information Infrastructure) and ISSG (Invasive Species Specialist Group) 2006.

Distribution

Previously recorded (see Kott 1985; Hewitt et al. 2002, p. NBII 2006): In Australia, it has been found in Port Phillip Bay from the 1970s. New record: Western Australia CSIRO SS10/05 (Shark Bay, Stn 118, 100 m, 07.12.05, QM G328137).

Originally recorded from the north-western Pacific the species has readily adapted to temperate locations in the northern and southern hemispheres to which it appears to have been introduced in the last half century.

Description

The single individual taken has a leathery, wrinkled test with longitudinal grooves. It is characteristically vertical, almost cylindrical, with both apertures close together and terminal. The gut loop is a simple vertical loop and there are eight longitudinal gonads on the left with the usual testis follicles in the body wall between the ovarian tubes.

Remarks

From its first recorded occurrence in Australia in the mid-1970s, this species has spread relatively slowly (see Hewitt et al. 2002, p. NBII (National Biological Information Infrastructure) and ISSG (Invasive Species Specialist Group), 2006), although the newly recorded colony from Shark Bay at 100 m suggests that there may be populations established in south-western Australia. The new record is also significant in that it is the only occurrence recorded outside temperate waters .