The colonial ascidian fauna of Fiordland, New Zealand, with a description of two new species
Author
Page, M. J.
National Institute of Water and Atmospheric Research Ltd (NIWA), Nelson, New Zealand;
Author
Willis, T. J.
Institute of Marine Sciences, School of Biological Sciences, University of Portsmouth, Portsmouth, UK
Author
Handley, S. J.
National Institute of Water and Atmospheric Research Ltd (NIWA), Nelson, New Zealand;
text
Journal of Natural History
2014
J. Nat. Hist.
2014-04-24
48
27 - 28
1653
1688
http://dx.doi.org/10.1080/00222933.2014.896487
journal article
10.1080/00222933.2014.896487
1464-5262
5193878
5ADC2C9D-28AC-4348-8B4D-F262A43DEA66
Ritterella sigillinoides
(Brewin, 1958)
Pesudodistoma sigillinoides
Brewin, 1958a
: p. 455
, fig. 2A
1
, A
2,
A
3
, A
4
Pesudodistoma
sigillinoides
:
Millar 1982
: p. 47
Material examined
New Records
:
Edwardson Sound (
45° 56.52’S
,
166° 37.56’E
,
14 m
,
29 February 2009
,
NIWA 49948
, three colonies); Caswell Sound (
45° 01.01’S
,
167° 08.40’E
,
18 m
,
3 February 2009
,
NIWA 49989
, two colonies)
.
Previously recorded
:
New Zealand
, Stewart Island (
Brewin 1958a
); east coast Stewart Island,
101 m
(
Millar 1982
).
Description
The colonies have numerous, small light-yellow capitate heads to
10 mm
diameter on slender tapering, almost woody, sometimes branching stalks up to
40 mm
high. As many as 20–30 zooids are embedded in a soft gelatinous test and open separately to the surface. The zooids are up to
14 mm
long with atrial and branchial siphons that have six low indistinct lobes and a stomach with 11 broken folds. No larvae were present in specimens collected from Fiordland.
Remarks
This species is relatively uncommon in Fiordland and easily distinguished from other species by soft gelatinous colony heads. The branching character in the specimens collected in Fiordland agrees with the description by
Millar (1982)
collected from
135 m
off Port Pegasus, Stewart Island. Deep emergent species are common in shallow water in Fiordland. The branching character seen in colonies here may be common to individuals in deeper environments.