Ascidiacea (Tunicata) from deep waters of the continental shelf of Western Australia
Author
Kott, Patricia
text
Journal of Natural History
2008
2008-04-30
42
15 - 16
1103
1217
http://dx.doi.org/10.1080/00222930801935958
journal article
10.1080/00222930801935958
1464-5262
5219188
Sigillina australis
Savigny, 1816
Sigillina australis
Savigny 1816
, p. 179
.
Kott 1990a
, p. 87
.
Distribution
Previously
recorded (see
Kott, 1990a
):
Western Australia
(
Montebello I.
to
Albany
);
South Australia
(
Great Australian Bight
,
Investigator Strait
);
New
South Wales
(
Port Jackson
to
Nelson’s Bay
);
New Zealand
(
North Island
).
New
records:
Western Australia
CSIRO
SS10
/05 (
Albany
,
Stn
26, 212 m
, 23.11.05,
QM
G328438
;
Kalbarri
,
Stn
96, 4,12,05,
435 m
,
QM
G328473-
5 specimens
; Kalbarri, Stn 102, 96–
98 m
, 05.12.05,
QM
G328445
;
Shark Bay
, Stn
115, 120 m
, 7.12.05,
QM
G328136
,
QM
G328142
;
Shark Bay
, Stn
116, 100 m
, 07.12.05,
QM
G328135
;
Shark Bay
, Stn
118, 100 m
, 07.12.05,
QM
G328134
; Carnarvon, Stn
124, 100 m
, 08.12.05,
QM
G328145
)
.
Description
The heads of the colonies of the present specimens are often relatively short, and the stalks sometimes longer and thinner than those of
Sigillina cyanea
(which the present species closely resembles in its colony and zooid form). However, it lacks the characteristic colour of the latter species and is more or less grey or colourless in preservative.
The newly recorded specimens from Kalbarri appear to have been dried, although a large larva was detected in a brood pouch at the postero-dorsal corner of the thorax of zooids that otherwise had disintegrated. The larval trunk is
0.9 mm
long and there are two vertically elongated antero-median adhesive organs. The tail is wound only halfway around the trunk. Other organs were not detected.
Remarks
The species has a similar range to that of
S. cyanea
, although its range is not interrupted across the Great Australian Bight and it also has been recorded from North Island (
New Zealand
). Generally, this species appears to be a temperate one extending into the tropics on the western Australian coast, while
S. cyanea
has a characteristically tropical range extending into temperate waters in south-western
Australia
and onto the central
New South Wales
coast on the eastern seaboard of the continent.