Leptoclinides placidus 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 : 1169-1170

Leptoclinides placidus Kott, 2001

( Figure 6F )

Leptoclinides placidus Kott 2001, p 75 ; 2004b, p 2473.

Distribution

Previously recorded (see Kott 2004b): central eastern coast (Byron Bay, Solitary I., Hervey Bay). New record: Queensland (Noosa Heads, QM G308766).

Description

The colony is robust and sheet-like and looks the same in life as it does in preservative, being white with black spots about 5 mm apart in the surface test. Spicules are absent from the superficial layer of test and the lower half of the colony, but are present on the base of the colony and they line the common cloacal cavities, which consist of deep primary cavities extending into posterior abdominal cavities. The spicules are stellate, to 0.08 mm diameter, and have 9–13 sturdy conical rays with pointed or chisel-shaped tips.

Remarks

The colony, with its three-dimensional common cloacal cavity and spotted appearance, resembles the South Australian L. maculatus Kott, 2001 (see Kott 2004b). However, the spicules of the latter species have fewer rays. The colony also resembles that of L. constellatus Kott, 2001 in the distribution and size of its spicules although L. constellatus has fewer rays. Leptoclinides tuberculatus Kott, 2004a has similar spicules but they have fewer rays and colonies lack the superficial bladder cell layer. The tropical Leptoclinides erinaceus Kott, 2001 and L. caυernosus Kott, 2001 both have spicules of similar form but they are significantly larger and the colonies are different from the present species. The present specimen conforms to descriptions of those previously assigned to this species except for the presence of black spots in the test, although Kott (2001) did report the presence of black pigment. Also, although a maximum number of 11 spicule rays in optical transverse section were reported previously for this species, some with 13 rays have been detected in the newly reported specimen.

The present species has been recorded only from the central eastern coast of Australia.

Figures

Figure 6. Scanning electron micrographs. (A) Atriolum irregulare (QM G323245); (B) Leptoclinides albamaculatus (QM G308876); (C) Leptoclinides dubius (QM G308892); (D) Leptoclinides durus (QM G308894); (E) Leptoclinides fluxus (QM G308817); (F) Leptoclinides placidus (QM G308766); (G) Polysyncraton cuculliferum (QM G3088458); (H) Polysyncraton gratum (QM G308891).