Didemnum pellucidum Kott, 2001

Kott, Patricia, 2007, New and little-known species of Didemnidae (Ascidiacea, Tunicata) from Australia (part 4), Journal of Natural History 41 (17 - 20), pp. 1163-1211 : 1188-1189

? Didemnum pellucidum Kott, 2001

( Figure 9F )

Didemnum pellucidum Kott 2001, p 222 ; 2005a, p 2450.

Distribution

Previously recorded (see Kott 2005a): Western Australia (Rottnest I., Yallingup); South Australia (Yorke Peninsula); Tasmania ( Port Davey ). New record: Tasmanian Canyons (Big Horseshoe, 160 m, QM G308886 ) .

Description

The colony forms a thin smear on some rocks. Spicules are present throughout, but are more crowded in the surface test than around the abdomina. The zooids are small and mutilated. Spicules are stellate, to 0.09 mm with 9–11 conical rays in optical transverse section.

Remarks

The spicules are like those of Didemnum patulum ( Herdman and Riddell, 1913) but are significantly larger. It has been questionably assigned to Didemnum pellucidum solely on the basis of its spicules which are the same size and have the same number of rays. The colony and its spicules closely resemble those reported by Kott (2005a).

Figures

Figure 9. Scanning electron micrographs. (A) Didemnum membranceum (QM G308854); (B) Didemnum microthoracium (SAM E3259); (C) Didemnum moseleyi (QM G308866); (D) Didemnum parau (QM G308859); (E) Didemnum patulum (QM G308769); (F) Didemnum pellucidum (QM G308886); (G) Didemnum perplexum (QM G308860); (H) Didemnum psammatode (QM G308879).