New syntheses and new species in the Australian Ascidiacea
Author
KOTT, PATRICIA
text
Journal of Natural History
2003
2010-12-03
37
13
1611
1653
https://www.tandfonline.com/doi/full/10.1080/00222930110104258
journal article
10.1080/00222930110104258
1464-5262
5260089
Polycitor columna
Kott, 1954
Polycitor columna
Kott, 1954: 153
.
Distribution
. Type locality:
Tasmania
(Maria I., 174–
155 m
,
syntypes
AM Y1297).
Description
.
Syntype
colonies have been re-examined. They have thick fleshy stalks about the same length as, and only slightly less diameter than, the head. The stalks taper toward the base. The test is translucent without contained sand. Zooids open around the head by separate six-lobed apertures. About 15 longitudual thoracic muscles per side extend in a wide band along each side of the abdomen. The branchial sac has 16 rows of about 35 stigmata per row. The stomach has four shallow longitudinal furrows. The large larvae (trunk 1.6 mm long) are as previously described with the tail wound half-way around the trunk.
Remarks
. Kott’s (1954) report of only 12 stigmata in each row is wrong. On re-examination of these specimens at least 35 stigmata have been detected on each side. The species most resembles
Polycitor calamus
Kott, 1990a
in its stalked colony, but
P. calamus
has a longer stalk, a shorter head, fewer stigmata per row, and 12 distinct longitudinal gastric folds.