Taxonomic revision of Ascidiacea (Tunicata) from the upper continental slope off north-western Australia
Author
Kott, Patricia
text
Journal of Natural History
2009
2009-07-22
43
31 - 32
1947
1986
http://dx.doi.org/10.1080/00222930902993708
journal article
10.1080/00222930902993708
1464-5262
5216855
Culeolus herdmani
Sluiter, 1904
Culeolus herdmani
Sluiter, 1904
, p. 105
.
Kott 2002
, p. 63
and synonymy.
Distribution
Previously
recorded (
Kott 2002
):
western Australia
(off
Collier Bay
,
Lacepede Archipelago
,
Cape Leveque
);
New Caledonia
;
Indonesia
;
Philippines
;
Sea
of
Japan
.
New
record:
CSIRO 0507
western Australia
(
Station
082-171,
Imperieuse
,
18.46 S
120.15 E
,
80 m
,
Sled
tow, 19.6.07,
QM
G328562
)
.
Although the new record is of a single specimen from
80 m
, the previous records from north-western
Australia
are of from one to
six specimens
at depths from
400–500 m
and the specimens from the
western Pacific
(
New Caledonia
:
Monniot C and Monniot F (1991))
were taken from
400–1000 m
.
It
is known from soft bottoms and appears to be a relatively commonly occurring species
.
Description
The species is readily identified by its long wiry-looking stalk extending from just ventral to the branchial aperture which is directed down toward the base of the stalk The sessile atrial aperture about one-third of the body length from the terminal (posterior) end of the body, is a transverse slit. The test is characteristically translucent and has small scale-like blisters, each with a small point in the centre. The body wall has circular muscles around each aperture and a few fine longitudinal bands radiate from each of the apertures. On each side of the body a narrow but conspicuous muscle band extends from one sides of the branchial aperture to the same side of the atrial aperture. The branchial tentacles are branched, the dorsal lamina has pointed languets, and the dorsal tubercle is a C-shaped slit with one horn in-rolled.
The species is remarkably uniform, without significant variations in its morphology. It has the usual geographic range recorded for the group of Indo-west Paciific species detected (in this survey) at intermediate depths. Like the sympatric stalked species,
Pterygascidia mirabilis
, it appears to be a common component of the fauna in this area and at this depth between the fauna of the continental shelf and that of the lower continental slope and abyssal depths.
The stalk of the present species is particularly long, thin and wiry, possibly anchoring the individual in soft sediments in habitats where currents affect its orientation and ensure that the open branchial aperture is presented to the oncoming currents, thus compensating for the lack of ciliated stigmata.