New and little-known species of Didemnidae (Ascidiacea, Tunicata) from Australia (Part 3)
Author
Kott, Patricia
text
Journal of Natural History
2005
2005-06-30
39
26
2409
2479
http://dx.doi.org/10.1080/00222930500087077
journal article
10.1080/00222930500087077
1464-5262
5215680
Trididemnum areolatum
(
Herdman, 1906
)
(
Figure 16H
)
Didemnum areolatum
Herdman 1906
, p 337
.
Trididemnum areolatum
:
Kott 2001
, p 258
and synonymy.
Distribution
Previously recorded (see
Kott 2001
): Queensland (Hervey Bay–Lizard I.); Central Pacific (Kure and Line Is);
French Polynesia
;
New Caledonia
; Indian Ocean (
Sri Lanka
). New record: Northern Territory (Bynoe Harbour, QM G308746).
Description
The newly recorded specimen is a gelatinous, encrusting colony of even thickness. A superficial layer of bladder cells mixed with some black pigment particles and some sparse spicules overlies a single layer of spicules. Spicules also are in a layer lining the common cloacal cavities. The spicules are large (to
0.1 mm
diameter) and have 13–15 stubby short conical to rounded rays in optical transverse section.
Zooids have black squamous epithelium and a black endostylar pigment cap. In this specimen the gut is filled with large, muddy faecal pellets that obscure the zooids. Eight coils of the vas deferens surround the undivided testis.
Remarks
Differences from previously recorded specimens were not detected.