New and little-known species of Didemnidae (Ascidiacea, Tunicata) from Australia (part I)
Author
Kott, Patricia
text
Journal of Natural History
2004
2004-03-20
38
19
731
774
http://www.tandfonline.com/doi/abs/10.1080/00222930310001647334
journal article
10.1080/00222930310001647334
1464-5262
4653689
Leptoclinides cucurbitus
sp. nov.
(
figure 1
)
Distribution.
Type locality:
Tasmania
(
Tasman
Peninsula, Waterfall Bay, Paterson’s Arch on rock wall, coll. K. Gowlett Holmes,
18 September 1998
,
holotype
SAM E2905).
Description
. The colony is an encrusting sheet with evenly spaced rounded swellings, each with a terminal common cloacal aperture, on the upper surface. A large central common cloacal cavity occupies the surface swellings and canals from the periphery of the cavity extend out amongst the zooids (at oesophageal level). Spicules are present throughout. They are up to
0.09 mm
diameter, with short, sharply pointed rays,
11–13 in
optical transverse section, the rays are not crowded and their bases are well separated from one another on the central test mass. The ray length
/
spicule diameter ratio is only about 0.1. Zooids open to the surface through stellate branchial apertures, each with a plug of spicules in the siphon. A short posteriorly orientated atrial siphon arises from the posterior one-third of the dorsal surface and a large circular plate-like lateral organ is just ventral to the base of the atrial siphon. Zooids have large eggs against the dorsum of the post-pyloric gut loop but testis follicles are not present. Larvae are not known.
Remarks
. In the
holotype
, few details of zooid structure were determined and the species is characterized by its unique spicules with their very short pointed rays.
Leptoclinides imperfectus
Kott, 1962
has a similar colony, but its spicules have longer rays, and some have truncated or chisel-shaped tips which are not in the present species.