New species and genera of colloniids from Indo-Pacific coral reefs, with the definition of a new subfamily Liotipomatinae n. subfam. (Turbinoidea, Colloniidae)
Author
Mclean, James Hamilton
Natural History Museum of Los Angeles County, 900 Exposition Blvd, Los Angeles, California 90007 (USA) jmclean @ nhm. org
jmclean@nhm.org
text
Zoosystema
2012
2012-06-30
34
2
343
376
http://dx.doi.org/10.5252/z2012n2a10
journal article
10.5252/z2012n2a10
1638-9387
5165469
Liotipoma dimorpha
n. sp.
(
Figs 2G
;
6
;
7
)
TYPE MATERIAL. —
Holotype
: LIFOU, stn 1442,
Loyalty Islands
,
Lifou
,
Cape Aimé Martin
,
Santal Bay
,
20°46.4’N
,
157°02.0’E
,
47 m
, diving team,
13-14.XI.2000
,
♂
shell, H 3.0, D
4.3 mm
(
MNHN 24761
,
Fig. 6
A-D).
Paratypes
:same data as
holotype
,
♀
shell, H. 3.0, D
5.1 mm
(
MNHN
24764,
Fig. 7
A-D). — MONTROUZIER expedition, stn 1331,
New Caledonia
, Grand Koumac Reef,
♂
shell, H 2.6, D 4.0 mm (
MNHN
24763,
Fig. 6
E-H). — stn 1450,
♀
shell, H 2.5, D
4.5 mm
(
MNHN
24765,
Fig.7
E-H).
ADDITIONAL MATERIAL. —
Loyalty Islands
. LIFOU, stn 1435,
Loyalty Islands
,
Lifou
,
Pointe Lefèvre
,
Santal Bay
,
20°55.2’S
,
167°00.7’E
,
5-30 m
,
8.XI.2000
, diving team,
1 immature
with operculum (
MNHN
,
Fig. 2G
)
;
1 ♂
shell at
4.6 mm
diameter and
2 immature
(
MNHN
). — LIFOU stn 1434,
Huca Hutighé
,
Santal Bay
,
20°52.5’S
,
167°08.1’E
,
5-20 m
,
6.XI.2000
, diving team,
7 ♂♂
shells, of which the largest is
4.8 mm
diameter, plus
3 immature
specimens (
MNHN
). — LIFOU stn 1432, Shelter Reef,
Santal Bay
,
20°53.5’S
,
167°01.7’E
,
12-32 m
,
21.XI.2000
, diving team, 2 mature
♂♂
shells at
4.8 mm
diameter, plus
7 immature
(
MNHN
)
.
New Caledonia
. MONTROUZIER expedition, stn 1331, Grand Koumac Reef, Koumac Sector,
20°40’S
,
162°12’E
,
55-57 m
,
X.1993
,
2 specimens
, lip not fully formed on second specimen (
MNHN
,
Fig. 6
E-H).
TYPE LOCALITY. —
Loyalty Islands
, Lifou.
DISTRIBUTION. — Lifou,
Loyalty Islands
, and Koumac Reef,
New Caledonia
.
FIG. 6. —
Liotipoma dimorpha
n. sp.
, male shells:
A-D
, holotype (MNHN 24761, stn 1442), Santal Bay, Lifou, Loyalty Islands, 47 m, H 3.0, D 4.3 mm;
E -H
, paratype (MNHN 24763, stn 1331), Grand Koumac Reef, Koumac Sector, New Caledonia, 55-57 m, H 2.6, D 4.0 mm. Scale bars: 1 mm.
ETYMOLOGY. — The name means two forms, with regard to sexual dimorphism.
DESCRIPTION
Male shell (
Fig. 6
)
Whorls 3.3; profile moderately high for genus; keel at periphery, slightly higher than mid-whorl; profile below shoulder evenly rounded; subtending cord not strongly projecting. Axial sculpture of strong ribs, 23-25 on last whorl in basal view; strongly spinose in early whorls, more closely spaced in final quarter whorl; spines projecting forward in direction of growth. Spiral sculpture of three cords on shoulder, beaded at intersections with axial ribs. Base with strong subtending cord, and two cords of nearly equal strength between peripheral cord and subtending cord; base with shallow pits on outer side of subtending cord. Umbilicus bordered by broad emergent cord, overridden by narrow axial ribs; umbilicus narrow, obstructed by massive extension of inner lip. Final lip massive, extending for ⅓ of final quarter whorl, with successively decreasing layers of deposition, with indentations conforming to spiral sculpture. Plane of aperture aligned to intersect axis of coiling at umbilicus. Aperture nearly radial, tongue short, triangular, in same plane as plane of aperture. H 3.0, D
4.3 mm
(
holotype
).
Female shell (
Fig. 7
)
Of higher profile than male shell; emergent cord high on whorl (in basal view), forming protruding carination that enlarges umbilical cavity, subtending cord and first basal cord narrow, interconnected by extensions of axial ribs; tongue not projecting into umbilical cavity for specimen of
Figure 7
A-D, slightly projecting in specimen of
Figure 7
E-H. H 3.0, D 5.1 (
Fig. 7
A-D).
Operculum (
Fig. 2G
)
Known from immature specimen, with narrow pit in center.
REMARKS
Liotipoma dimorpha
n. sp.
is characterised by having forward directed spines, a narrow subtending cord and an even narrower first basal cord, by which it differs from
L. mutabilis
n. sp.
, in which the subtending cord and the first basal cords are significantly broader. By that distinction it also possible to connect the female shell to the male shell and also to separate the separate the female shell from that species. The female shell of this species (
Fig. 7
) is unlike the female shell of both
L. wallisensis
and
L. mutabilis
n. sp.
in having the emergent cord positioned higher (in umbilical view), so that the tongue does not depress it. Female shells are larger than male shells, as expected. The two illustrated male shells differ in the length and direction of the tongue, but these differences are considered intraspecific. In
Figure 6
A-D it is shorter and in
Figure 6
E-H it is longer and not in alignment with the plane of the aperture.