Aplidiopsis confluata Kott, 1992

Kott, Patricia, 2006, Observations on non-didemnid ascidians from Australian waters (1), Journal of Natural History 40 (3 - 4), pp. 169-234 : 196

Aplidiopsis confluata Kott, 1992

( Figure 9F, G )

Aplidiopsis confluata Kott 1992a, p 468 .

Distribution

Previously recorded (see Kott 1992a): Tasmania (Ninepin Point). New record: Tasmania ( Port Davey , 4–6 m, SAM E3281 ) .

Description

The colony is soft, mushroom-shaped with a circular flat head on a short narrow stalk from the centre of the under surface. Sand, present on the outer surface of the head, is sparse in the soft internal test of the head but is crowded in the stalk. Conspicuous common cloacal apertures are present around the margin of the upper surface of the colony and zooids form circular systems around them or they line the canals that radiate to them. Photographs show the colony to have been red in life. Zooids have a long strap-like atrial lip from the body wall anterior to the opening and it has a fringe of four to six pointed projections along its free edge. A small papillum is present behind the atrial aperture. Six fine longitudinal muscles on the anterior part of the thorax fade out halfway down the sides. Sixteen rows of about 14 stigmata are on each side of the body. The stomach is smooth. The posterior abdomen is long and narrow and muscles were not detected on it.

Remarks

Previously the species was known only from its holotype, which is a larger colony with more crowded zooids and systems but otherwise is similar to the newly recorded specimen.

Figures

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).