New records of deep-sea ascidians (Tunicata, Ascidiacea) from the New Caledonia region
Author
Monniot, Francoise
text
Zootaxa
2021
2021-07-06
4996
3
443
468
journal article
10.11646/zootaxa.4996.3.2
1175-5326
5074595
A1982CE0-AD2F-496B-80AB-FB3C4FA69F7A
Scotiazoa lilium
(
Monniot & Monniot, 1982
)
Figure 6
Stations: Kanadeep CP 5095; CP 5109. Nine specimens.
Protoholozoa lilium
Monniot C. & Monniot F. 1982
.
All colonies are brittle, very soft with a triangular head above a long cylindrical peduncle (
Fig. 6A
). The diameter of the head (always damaged) is about
1cm
, the longest peduncle is
6 cm
with
2 mm
in diameter. The zooids have their thorax and abdomen contained in the transparent tunic of the head the post abdominal vascular extensions extend into the peduncle. The thorax is in vertical position for most of the zooids with the atrial aperture at the top surface of the colony and the oral siphon near the peduncle. The thoraces are narrow
6 to 8 mm
long (
Fig. 6C
). The body wall is thin with circular muscles at the base of the oral siphon and with 15 transverse muscles along the thorax. There are eight to ten oral tentacles. The branchial tissue includes three transverse bars on each side attached to the endostyle and a dorsal membrane. This organisation corresponds to that of specimens from
New Caledonia
described as
Protoholozoa lilium
by
Monniot & Monniot (1991
,
Fig. 15
). The digestive loop encircles the hermaphrodite gonad. The ovary is anterior to the testis vesicles which are arranged in a rosette. A pedunculate brood pouch (
Fig. 6C
) is inserted at the base of the thorax and occasionally contains a single larva. The tadpole has three adhesive papillae in a triangle and one otolith (
Fig. 6B
). The larval body is
1.7 mm
long encircled by the tail.
The structure of the larva is typical of the
Holozoidae
family. It confirms the attribution of the species to the genus
Scotiazoa
instead of
Protoholozoa
(see
Monniot & Tatian 2020
).