Opisthobranchs from the western Indian Ocean, with descriptions of two new species and ten new records (Mollusca, Gastropoda)
Author
Yonow, Nathalie
text
ZooKeys
2012
197
1
130
http://dx.doi.org/10.3897/zookeys.197.1728
journal article
http://dx.doi.org/10.3897/zookeys.197.1728
1313-2970-197-1
Phyllidiopsis gemmata (Pruvot-Fol, 1957)
Fig. 25, Plate 74
Phyllidia gemmata
Pruvot-Fol, 1957: 121, figs. 50-53, pl. 1 figs. v, vi (no locality, NHMUK).
Phyllidiopsis gemmata
. -
Brunckhorst 1993
: 65, pl. 7H (La
Reunion
and Thailand).
Material.
Maldives: 33
x
15 mm pres. (NY-35), Maayafushi Tila, Ari Atoll, 23 m depth, 14 May 1990, leg. N Yonow ("white with 4 black lines, sole pale grey/white, foot extends beyond margin, has black line dorsally"); photographs of one individual, Maayafushi, South
Male
Atoll, March 1997, J Hinterkircher.
Description.
Living specimen very white and grey with two longitudinal black lines on each side of centre; each pair meets in front of its respective rhinophore. Outer black lines additionally meet posteriorly beyond anus and extend to mantle margin. Tubercles small and simple, although they may occur in clusters along tuberculate lines. Anus located on a tubercle, and was extended in life. Sole pale grey to white but top of foot with black line.
In preservative, specimen is distinctive: relaxed, with a very broad but thin mantle skirt. Central tubercles bead-like, arranged in three longitudinal lines; median one
several
tubercles wide. Skirt has scattered tubercles arranged neither in groups nor in lines. Anterior margin of foot narrow with thickened edge. Head distinctive, forming a
"funnel"
below broad fused oral tentacles, difficult to see in Fig. 25 (but similar to
Phyllidiella zeylanica
); gills and head white in preserved material.
Figure 25.
Phyllidiopsis gemmata
, 33 mm (NY-35), view of propodium, head, and oral tentacles.
Remarks.
There appear to be very few records of this species in the literature: the species identified as
Phyllidia
cf. gemmata by
Lin (1983)
, although listed as such by
Brunckhorst (1993)
, does not appear to be a species of
Phyllidiopsis
: the oral tentacles are the shape of those of species belonging to the genera
Phyllidia
and
Phyllidiella
, separated and long; the shape of the oral tentacles and the three dorsal ridges are more characteristic of
Phyllidia varicosa
or
Phyllidia alyta
although there is apparently no black line on the sole of the foot. Larger specimens of
Phyllidia gemmata
have perpendicular short black lines on the skirt (
Pruvot-Fol 1957
,
Brunckhorst 1993
, http://seaslugs.free.fr/nudibranche/a_intro.htm).