Pseudodistoma pilatum Kott, 1992

Kott, Patricia, 2006, Observations on non-didemnid ascidians from Australian waters (1), Journal of Natural History 40 (3 - 4), pp. 169-234 : 193

Pseudodistoma pilatum Kott, 1992

( Figures 3A–C , 9C )

Pseudodistoma pilatum Kott 1992a, p 439 .

Distribution

Previously recorded (see Kott 1992a): South Australia (Great Australian Bight, Gulf St Vincent). New records: Tasmania (Tasman Peninsula, 12–14 m, SAM E3244 ; 10–14 m, E3296). The newly recorded location is the most southerly recorded for this species .

Description

The colonies are as previously described, with the long, narrow, cylindrical sandy stalks arising from a common base and a terminal cylindrical glassy, transparent head with the relatively crowded zooids opening all around it. The sand becomes less crowded toward the top of the stalk and is only sparse in the head. In this species the oesophagus is long and the four-chambered pseudodistomid stomach is in the distal one-third of the relatively long abdomen. The posterior abdomen is long and narrow, about twice to three times the length of the abdomen, with two broad bands of muscles and a short row of gonads at the posterior end (in the base of the stalk).

Figures

Figure 3. (A–C) Pseudodistoma pilatum (SAM E3244): (A) thorax and oesophageal neck; (B) posterior end of abdomen; (C) end of posterior abdomen. (D) Polyclinum incrustatum (SAM E3274): thorax and abdomen. Scale bars: 0.2 mm.

Figure 9. In situ images of: (A) Pseudodistoma gracile (SAM E3270); (B) Pseudodistoma inflatum (SAM E3297); (C) Pseudodistoma pilatum (SAM E3296); (D) Polyclinum incrustatum (SAM E3274); (E) Polyclinum marsupiale (SAM E2866); (F) Aplidiopsis confluata (SAM E3281); (G) Aplidiopsis confluata (SAM E3282); (H) Synoicum citrum (SAM E3277).