The Diplommatinidae of Fiji - a hotspot of Pacific land snail biodiversity (Caenogastropoda, Cyclophoroidea)
Author
Neubert, Eike
Author
Bouchet, Philippe
text
ZooKeys
2015
487
1
85
http://dx.doi.org/10.3897/zookeys.487.8463
journal article
http://dx.doi.org/10.3897/zookeys.487.8463
1313-2970-487-1
4DA2B44E63514E61B9F258D33CBCE817
4DA2B44E63514E61B9F258D33CBCE817
Taxon classification Animalia Mesogastropoda Diplommatinidae
Diancta trilamellata
sp. n.
Figs 44-46
Type
material.
Holotype MNHN IM-2000-27433, paratypes MNHN/62 IM-2000-27434, NMBE 516871/10. Type locality: Viti Levu, Waivisa karst, 50-80 m, rainforest, -17.6879 178.4033, leg. Bouchet, 27.08.1998.
Etymology.
Latin numeral tres = three, and adjective lamellatus, -a, -um for possessing lamellae.
Diagnosis.
Shell sinistral, very small, teleoconch sculpture of coarse ribs, initially widely, then densely, spaced, last whorl ascending, aperture circular, detached from last whorl, with a palatal and a parietal lamella and broad columellar plate.
Description.
Shell sinistral, very small, whitish to yellowish; last whorl strongly constricted; protoconch broad, obtuse with a pitted microsculpture; umbilicus closed, very narrow periomphalum; teleoconch sculpture initially of coarse widely spaced ribs, changing to a more dense pattern on the central whorls, with a few very strong ribs on the last whorl; last whorl strongly ascending; aperture almost circular, not connected to the last whorl, peristome doubled and funnel-shaped, apertural rims connected; no dentition visible in the aperture by frontal view; internally with a palatal and a parietal lamella, columellar plate broad, subdivided into an inner and outer part, inner part with a slight notch.
Operculum corneous, flat, with a short apophysis, OD = 0.39.
Measurements.
Holotype (Fig. 44): H = 2.37; D = 1.91; PH = 1.13; PD = 1.17; W = 5.
Figures 44-46.
Diancta trilamellata
sp. n. 44 Holotype MNHN IM-2000-27433, Viti Levu, Waivisa karst, 50-80 m, H = 2.37 mm 45 paratype, last whorl opened to show internal lamellae (enlarged, not to scale) 46 operculum, 46a inner surface, 46b outer surface). Figure 44
x
10, Figure 46
x
40 magnification.
Distribution
(Fig. 170). only known from the type locality.
Remarks.
Diancta trilamellata
sp. n. superficially resembles
Diancta martensi
, but differs from it by its smaller size, the detached aperture, and the presence of a parietal lamella.