A review of the family Clenchiellidae (Mollusca: Caenogastropoda: Truncatelloidea)
Author
Ponder, Winston F.
Author
Fukuda, Hiroshi
Author
Hallan, Anders
text
Zootaxa
2014
3872
2
101
153
journal article
10.11646/zootaxa.3872.2.1
e9b8d555-d661-4f1a-86e8-f2a0acc38798
1175-5326
253224
F9F81CC8-E033-46B7-B73B-9FB777DF4116
Coliracemata
n. gen.
Type
species:
Coliracemata mortoni
n. sp.
Etymology.
Colis
(Latin): penis;
racemus
(Latin): bearing bunches or clusters of grapes. Gender feminine.
Diagnosis.
Shell minute (less than
1.9 mm
in diameter;
Fig. 16
). Spire flat except for raised protoconch, or slightly raised, periphery evenly convex; umbilicus moderate to wide. Whorls with many distinct, minutely wavy, spiral cords; spiral keels absent. Aperture near circular, peristome simple, prosocline, external varix absent. Operculum similar to
Clenchiella
with central peg but with triangular white, possibly calcareous, plate-like deposit covering muscle insertion area on middle of inner side. Head-foot colourless with no pigment; posterior end of foot rounded.
Radula
as for family, cusps on inner outer marginal teeth slightly larger than those on outer marginals. Penis with two or three clusters of many apocrine glands on dorsal edge of middle portion. Bursa copulatrix small to large; bursal duct short. Two seminal receptacles.
Remarks.
Members of this genus are distinguished from
Clenchiella
in having evenly rounded shells (no keels; although spiral threads cover the shell surface as in
Clenchiella
) which lack an apertural varix, no black pigment on the head-foot, rounded posterior end of the foot (instead of pointed) and massive glandular extensions from the penis that are composed of many small but distinct apocrine glands. The
radula
is very similar to those of species of
Clenchiella
but the operculum differs in having a white smear covering the muscle insertion area on its inner side.
Three species are confirmed as members of this genus as they are known anatomically. Two additional species with unknown anatomy are provisionally included here based on a general similarity in shell morphology. Specimens from a mangrove forest in Sembawang,
Singapore
were examined alive and are probably a member of this genus but the material is unavailable for description.