Corresponding author: Menno Schilthuizen (
Academic editor: F. Köhler
We present reviews of the Sabah (Malaysia, on the island of Borneo) species of the following problematical genera of land snails (
Vermeulen JJ, Liew TS, Schilthuizen M (2015) Additions to the knowledge of the land snails of Sabah (Malaysia, Borneo), including 48 new species. ZooKeys 531: 1–139. doi:
Apart from a few revised groups (
At present, the material available to us largely consists of dry specimens, generally extracted from soil samples gathered by the authors since 1986. The samples from Sabah have yielded close to 8000 lots in our combined collections. Therefore, the species are distinguished by shell characters only. We are aware of the shortcomings of these proceedings, but we feel that investigations into the Sabah snail fauna are better helped by describing the species now, rather than by waiting until we have preserved animals of a representative selection of the species.
In the enumerations of localities, words are used from the Malay language:
The material studied derives from the following collections, indicated with abbreviations: ( (Naturalis, the natural history museum of the Netherlands) (private collection J.J. Vermeulen, Leiden, the Netherlands)
The drawings were made by the first author, with the aid of a Wild M8 stereo microscope with a Camera Lucida device; the SEM images were made by the second author. Also, all
Shell very small to medium-sized, dextral, globose, ellipsoid, ovoid or conical, rarely almost discoid. Last whorl without a pore near the suture; on the inside usually without a constriction, rarely with a constriction (
In marine and intertidal environments, in the tropics also terrestrial. Globally distributed in temperate and tropical regions.
We provide a review of the terrestrial
Land snails. Spire without constriction. Umbilicus often with a slight periomphalic thread starting on the columellar side of the peristome, close to the columellar corner, and spiralling (steeply) upwards. Peristome usually not or hardly hardly thickened (except sometimes in gerontic shells).
Within several species long and slender shells occur next to shorter and wider ones. The periomphalic thread is sometimes inconspicuous and difficult to see, a mere strip of somewhat rougher sculpture that betrays its presence by the dirt that accumulates around it.
The family typically inhabits intratidal and supratidal environments. Only few genera live in fresh water or on land.
We divide the genus into two informal groups.
Malaysia, Sabah, Interior Province, Sepulut valley, Gua Sanaron (leg. J.J. Vermeulen & M. Schilthuizen,
Shell minute, thin, somewhat translucent, white. Surface shiny. Spire conical with approx. flat sides, apex obtuse, whorls convex, sometimes slightly shouldered.
Primary and secondary forest on limestone bedrock, at 0–700 m alt.
Shares the prominent, prosocline radial sculpture with
The material of this species displays variability in two characters but we are not able to divide it into discrete units. The ratio height/width varies, and with it the width of the umbilicus. The spacing of the radial ribs above the periphery also varies; specimens with moderately spaced radial ribs above the periphery have the radial ribs bifurcating more frequently below the periphery. Next to this, the whorls are more depressed in some specimens than in others.
The name refers to the shape of the riblets [
Malaysia, Sabah, Interior Province, Pinangah valley, Batu Urun (= Bukit Sinobang) (leg. J.J. Vermeulen,
Shell minute, thin, somewhat translucent, white. Surface shiny. Spire conical with flat or slightly concave sides, apex obtuse, whorls convex, sometimes slightly shouldered.
(Disturbed) primary forest on limestone bedrock, at c. 400 m alt.
Differs from
Just as in
The name refers to the wide umbilicus.
Shell very small, rather thick, hardly translucent, white. Surface dull or somewhat shiny. Spire conical with approx. flat or slightly convex sides, apex obtuse, whorls moderately convex.
Primary and secondary forest on limestone bedrock, often in caves. Alt. 0–500 m.
The largest
Malaysia, Sabah, Interior Province, Pinangah valley, Batu Urun (= Bukit Sinobang) (leg. J.J. Vermeulen,
Shell minute, rather thin, translucent, white. Surface shiny. Spire conical with slightly convex sides to ovoid, apex (broadly) obtuse, whorls slightly to moderately convex, sometimes slightly shouldered.
Primary and secondary forest on limestone bedrock, at 0–700 m alt.
Characterized among the Sabah species by the more or less ovoid outline of the shell.
Differs from
The index h/w is highly variable, and the umbilicus may be wider than in the illustrated shell.
The name refers to the shell outline [
Malaysia, Sarawak, 4th Division, Niah Caves, South side of limestone area, West side of quarry, soil-filled crevice opened in quarry (leg J.J. Vermeulen,
Shell minute (one of the smallest Borneo snail species), thin, translucent, white. Surface shiny. Spire conical with almost flat to distinctly convex sides, apex broadly obtuse, whorls moderately convex, sometimes slightly shouldered.
(Disturbed) primary forest on limestone bedrock. Alt. 0–500 m.
Most similar to
Also similar to
The name refers to the size [
Malaysia, Sabah, Tawau Province, Batu Baturong c. 50 km W.S.W. of Lahad Datu (leg. J.J. Vermeulen & H. Duistermaat,
Malaysia, Sabah,
Shell minute, rather thin, somewhat translucent, white. Surface shiny. Spire conical with flat to slightly convex sides, apex somewhat narrowly obtuse, whorls (moderately) convex, sometimes slightly shouldered.
(Disturbed) primary forest on limestone bedrock, at c. 100 m alt.
Most similar in size and shell sculpture to
The general shell shape is virtually identical to
The name refers to the shell surface [
Malaysia, Sabah, Kudat Province, Balambangan Island, South end, Batu Sireh (leg. J.J. Vermeulen & M. Schilthuizen,
Description: Shell minute, rather thin, slightly translucent, corneous to white. Surface shiny. Spire conical with approx. flat sides, apex somewhat narrowly obtuse, whorls convex, often somewhat shouldered.
Primary forest, primary coastal woodland and secondary vegetation on limestone bedrock, also found in soil over sandstone and volcanic bedrock, at 0–1400 m alt.
Characterized among Sabah
Also similar to
Most Sabah samples have a slightly oblique spiral striation. In Sarawak shells with a spiral striation parallel to the suture predominate in most localities.
Samples from Mantanani and Balambangan Islands contain relatively large shells of dark colour. Similar shells are found locally in the Kinabatangan River valley; but towards the West populations grade into a smaller form with white shells, as is found in Gunung Mulu N.P., Sarawak. A sample from Kalimantan contains medium-sized and white shells.
The samples
The name refers to the shell surface [
Land snails. Spire with a slight constriction about 1/2 whorl back of the aperture, consisting of a circular rim on the inner surface, on the outside this rim shines through as a thin, white line. Umbilicus without periomphalic thread. Peristome thickened.
The presence of a constriction distinguishes
Originally included in the
Malaysia, Sabah, Tawau Province, Batu Baturong c. 50 km W.S.W. of Lahad Datu (leg. J.J. Vermeulen & H. Duistermaat,
Shell minute, rather thick, about opaque, pale corneous. Surface shiny. Spire conical with approx. flat or slightly concave sides, apex somewhat narrowly obtuse, whorls moderately convex.
Primary forest on limestone soil, at 100–300 m alt.
The sculpture uniquely identifies the species among the Sabah snail fauna.
The name refers to the shell surface [
Shell small to very large, dextral, discoid to ovoid to conical. Last whorl with or without a pore near the aperture; on the inside with (
Terrestrial; ground- or tree-dwellers. Asia, Africa, Australia, and Oceania; fewer species in temperate regions.
Shell very small, white to pale corneous or pale greenish, without any colour patterns. Surface shiny or glossy. Spire rather high-conical, to approx. flat with a protruding apex. Radial sculpture absent or inconspicuous. Spiral sculpture prominent, consisting of distinct cords and keels. Peristome simple or double, expanded or not, without a notch in the angular corner. Height up to 2.3 mm. Umbilicus wide.
Borneo species of
The two Borneo species of
We provide a review of the Sabah species of the genus.
The cyclophorid fauna of Borneo includes a small number of species with small shells with conspicuous spiral cords:
For the Borneo material we conclude that the species listed below generally differ from the ones included in
We divide the genus into three informal groups.
Malaysia, Sabah, Upper Padas valley, Matang River South of Long Pasia (leg. J.J. Vermeulen,
Shell very small, rather thick, somewhat translucent, whitish. Surface shiny. Teleoconch whorl entirely detached, more or less in one plane; apex protruding from the plane, distinctly oblique.
Found in montane forest, in a sandstone rock crevice near a small stream in thick leaf litter, at 1100 m alt.
Uniquely identified among the Sabah species by the tubular, detached teleochonch.
Species from elsewhere with a detached teleoconch are
Named in honour of Dr. Geoffrey Davison, tireless advocate of nature conservation in Southeast Asia.
Malaysia, Sabah, West Coast Province, Crocker Range N.P., near the km 54 marker on the road Kota Kinabalu-Tambunan, Gunung Mas (leg. J.J. Vermeulen & M. Schilthuizen,
Shell very small, rather thick, hardly translucent, pale greenish. Surface shiny. Spire rather high-conical. Radial sculpture: fine growth lines, locally grading into fine, densely placed riblets.
Primary montane oak forest on sandstone bedrock, in leaf litter, sub-alpine forest on ultrabasic and granodioritic bedrock, 1300–1400 m (Crocker Range), 2000–3400 m (Mount Kinabalu) alt.
Similar to
The name refers to the peristome [
Shell very small, rather thick, somewhat translucent, white to pale corneous. Surface shiny. Spire conical, apex not protruding, not oblique.
Primary forest on sandstone and limestone soil, 400–1200 m alt.
Elsewhere in Borneo, the conical spire and the angular whorl profile identify the species.
Malaysia, Sabah, Tawau Province, Danum Valley Conservation Area (RMNH5003920).
Shell very small, rather thick, somewhat translucent, white to pale (yellowish) green. Surface shiny or glossy. Spire almost flat, but apex protruding, slightly oblique.
Primary forest on limestone soil, rarely on sandstone, 0–600 m alt.
Well characterized among Sabah
Elsewhere,
The name refers to the shape of the apex [
Malaysia, Sabah, Interior Province, Sepulut valley, Gua Sanaron (
Shell very small, rather thick, somewhat translucent, off-white to pale greenish yellow. Surface shiny. Spire rather low-conical, apex slightly protruding, slightly oblique.
Primary and secondary forest. Predominantly on limestone soil, scattered records from sandstone, 0–1000 m alt.
Differs from
The drawn specimen has relatively thick spiral cords, specimens with thinner cords occur.
The name refers to the constricted peristome.
Indonesia, Kalimantan Timur, Sangkulirang Peninsula, Liang Belana near Merabu (
Shell very small, rather thick, somewhat translucent, corneous to brown. Surface shiny or glossy. Spire low-conical with convex sides, apex protruding, slightly oblique.
Found in forest on ultrabasic bedrock. Elsewhere also on limestone bedrock, 400–500 m alt.
The spire height of
The name refers to the peripheral keel [
Shell very small, rather thick, somewhat translucent, white to pale greenish. Surface shiny or glossy. Spire conical with convex sides, apex somewhat protruding, hardly oblique.
Primary forest on sandstone and limestone soil, 200–800 m alt.
Uniquely identified among the Sabah species by the double peristome.
Elsewhere,
Shell small, white to pale corneous or pale greenish, usually marked with brown. Surface dull or shiny. Spire low to high-conical. Radial sculpture usually consisting of growth lines, locally grading into riblets. Spiral sculpture usually consisting of inconspicuous to distinct threads, sometimes with a peripheral keel. Peristome simple or double, expanded or not, with a notch in the angular corner. Height 4–12 mm. Umbilicus narrow to wide.
The genus
The Borneo species, numbering about 25, have not yet been revised. Nonetheless, we feel confident to describe one, highly distinctive, new species.
Malaysia, Sabah, Interior Province, Crocker Range N.P., Gua Laing c. 12 km North of Keningau (leg. J.J. Vermeulen,
Shell small, rather solid, opaque, white to yellowish, with vaguely outlined pale brown radial blotches on the upper surface. Surface slightly shiny. Spire conical, top distinctly protruding, periphery sharply angular, whorls almost flat to slightly convex (in large specimens) above the periphery, slightly convex below; transition from basal to umbilical area somewhat less distinctly angular than the periphery. Whorls not channeled towards the suture.
Secondary forest on limestone bedrock. Alt. c. 500 m. Sabah: Crocker Range, Laing Cave near Keningau only. Endemic to Sabah.
Shares the angular periphery and the whorls which are only slightly convex above and below with
The name refers to the fact that the upper and lower surface of the last whorl are about equally convex [
Shell (very) small, dextral or less frequently sinistral, ellipsoid to ovoid to conical, or cylindrical. Last whorl without a pore near the aperture; on the inside with a constriction. Coiling axis changing direction one to several times during development, often resulting in (partly) detached whorls. Sculpture: usually a distinct radial sculpture, spiral sculpture subordinate; rarely with spiral sculpture only, or without sculpture. Aperture rounded to somewhat angular above; peristome (distinctly) thickened. Umbilicus closed, or open, narrow. Operculum corneous, paucispiral (Family description based on Webster et al. 2012;
Rock and soil foragers, frequently associated with limestone substrates. Asia (from India, China, Japan Southwards) to Australia, and Oceania.
The Borneo species of
Malaysia, Sabah, Tawau Province, Batu Baturong c. 50 km W.S.W. of Lahad Datu (leg. J.J. Vermeulen & H. Duistermaat,
Shell dextral, conical, with the last whorl or the last two whorls widest; sides flat or slightly convex. Suture impressed.
(Disturbed) primary forest on limestone bedrock, at c. 100 m alt.
Uniquely identified by the parietal lamella, which runs over the full length of the tuba and which is visible as a pearietal tooth deep in the aperture.
In
The name refers to the two teeth in the aperture [
Malaysia, Sabah, Interior Province, Gunung Trusmadi slopes, Gua Loloposon (
Shell dextral, fusiform, with the penultimate whorl widest. Suture impressed.
Found in primary forest on limestone soil. Alt. 900–1000 m.
Uniquely identified among Sabah
The name refers to the diagnostic character [
Shell (very) small, dextral, ellipsoid to ovoid to conical. Last whorl without a pore near the aperture, on the inside without a constriction. Sculpture absent, or inconspicuous to distinct spiral and/or radial sculpture present, often fused to nodular structures. Aperture rounded to somewhat angular above; peristome usually not thickened. Umbilicus usually covered by a thickened callus, an extension of the peristome. Operculum calcareous, paucispiral, with a central calcareous peg projecting from the inner surface (Family description adapted from
Widespread in humid terrestrial environments, often associated with limestone habitats. Palearctis, Africa, but most diverse in Southeast Asia to Australia and Oceania.
The family is poorly known and has not been revised in the past 140 years and as a consequence, the status of the various genus names (including
Malaysia, Sabah, Interior Province, Sepulut valley, Gua Pungiton (
Shell minute, rather solid, translucent, white; spire conical with convex sides to approx. ovoid; apex rounded. Surface with a silky luster. Whorls moderately convex, rounded; last whorl somewhat more narrowly rounded to slightly angular at the periphery, rounded below.
Primary and secondary forest on limestone bedrock. Alt. up to c. 500 m.
The small size, hardly over 1 mm high at 3 whorls, characterizes the species.
The name refers to the white shell [
Malaysia, Sabah, Sandakan Province, Kinabatangan valley, Batu Keruak 2 near Sukau (
Shell minute, solid, opaque or nearly so, orange to white; spire conical with convex sides; apex rounded. Surface with a silky luster. Whorls distinctly convex, rounded; last whorl rounded at the periphery.
Primary and secondary forest on limestone bedrock. Alt. up to c. 100 m.
Most similar to
The name refers to the shape of the aperture [
Snails or semi-slugs. Shell (very) small to very large, dextral or sinistral, (low-)conical, ellipsoid, lenticular or discoid; semi-slugs with a (partly) reduced shell. Sculpture absent, or inconspicuous (rarely more distinct) spiral and/or radial sculpture present. Aperture without teeth or lamellae, peristome usually thin and not reflected. Umbilicus closed or open, narrow (Family description adapted from Baker (1941), and
Generally forest species found on leaf litter and vegetation. Throughout South, East, and Southeast Asia, and Oceania, with a few species circumtropically introduced.
Malaysia, Sabah, West Coast Province, Kinabalu N.P., summit trail, near Layang-layang at 2641 m (Leg. Liew T.S.,
Examined material from Sabah:
Shell small, membranous, leathery with only a thin calcareous layer on the inside, somewhat translucent, greenish or brownish, low-conical with slightly concave sides; apex narrowly rounded. Surface shiny.
Primary forest on sandstone or granodiorite bedrock. Alt. 2400–2700 m.
We assume this is the shell of an ariophantid semi-slug. Among the genera already reported from Borneo, it fits best in
Only damaged material was available to us, with some dried remnants of the animal.
The name refers to the shell sculpture [
Malaysia, Sabah, West Coast Province, Crocker Range N.P., Ulu Kimanis, along Keningau-Kimanis road (
Shell medium-sized, very thin, translucent, pale yellowish green, conical with slightly concave (juveniles) to slightly convex (adults) sides; apex narrowly rounded. Surface glossy.
Primary forest on sandstone bedrock. Alt. 1200–1500 m.
Very similar to
Adult shells of
The name refers to the green body of the living animal [
Shell minute or very small, thin, lenticular, inflated-lenticular to depressed-ovoid; spire almost flat to moderately elevated. Surface shiny or glossy. Sculpture very fine, hardly prominent. Umbilicus open but very narrow, to closed, often partly or entirely covered by a minute, triangular spur protruding from the columellar corner of the peristome; this spur lacking or inconspicuous in juveniles. Dimensions: Width of adult shells 1.7–3.6 mm.
The genus
Borneo
Placement of
We provide a review of the Sabah species of
Malaysia, Sabah, Interior Province, Gua Pungiton (
Shell very small, thin, translucent, white, lenticular; spire almost flat or slightly elevated. Surface glossy. Whorls slightly convex.
Rainforest, periodically dry, shrubby woodland, coastal woodland, secondary forest and other degraded vegetation; on limestone, sandstone and granitic soil, up to 3500 m alt.
Characterized among the Borneo
Elsewhere,
The name refers to the spur covering the umbilicus [
Malaysia, Sabah, Mantanani Group, Pulau Lungisan (
Shell very small, (rather) thin, almost opaque or slightly translucent, white, lenticular; spire almost flat to moderately elevated. Surface with a silky luster. Whorls slightly convex.
Coastal woodland on limestone soil.
Uniquely identified within
The name refers to the callus in the aperture.
Malaysia, Sabah, Tabin Valley (
Shell very small, thin, almost (slightly) translucent, white, lenticular; spire almost flat to slightly elevated. Surface with a silky luster. Whorls slightly to moderately convex.
Rainforest, seasonally dry coastal forest and shrubby forest on limestone bedrock, up to 1000 m alt.
Differs at first sight from
Elsewhere,
SEM images at 400 times magnification show that the areas in between the spiral grooves on the upper surface of the teleoconch have a ‘welded’ appearance.
The name refers to the sculpture [
Shell minute, thin, somewhat translucent, pale yellowish to pale corneous, lenticular; spire moderately elevated, conical with a rounded apex. Surface moderately glossy, or with a silky shine. Whorls moderately convex.
Primary and secondary forest, coastal woodland on limestone, sandstone and volcanic bedrock, up to 1100 m alt. Elsewhere also in more severely degraded environments such as
Shares the small size, slowly expanding whorls, and pitted protoconch with
Shell very small, thin, translucent, pale yellowish green to yellowish brown, approx. lenticular; spire moderately elevated, conical with a rounded apex. Surface shiny, glossy below. Whorls moderately to distinctly convex.
Primary forest on granodiorite soil, 2200–3200 m alt., elsewhere at 0–1700 m alt.
Uniquely characterized within Group 2 by the fine and dense radial ribbing above the periphery.
Elsewhere,
The description includes extralimital material as well. The Kinabalu material has slightly coarser radial riblets than the type.
Malaysia, Sabah, Mt. Trusmadi, Gua Dawaras (
Shell very small, thin, translucent, yellowish brown, discoid-lenticular; spire almost flat. Surface glossy. Whorls moderately convex.
Primary forest on limestone soil, 1600–1700 m alt.
Identified by the distinctly more rapidly expanding whorls than in any other species in Group 2.
The name refers to the shell shape [
Shell very small, thin, somewhat translucent, brown, lenticular; spire slightly to moderately elevated, conical with a rounded apex. Surface glossy. Whorls slightly convex.
Primary and secondary forest on limestone and sandstone soil, up to 1400 m alt.
The only Sabah species within group 2 of
Shell very small, thin, translucent, straw yellow to brown, approx. lenticular; spire moderately elevated, conical with a rounded apex. Surface shiny. Whorls moderately convex.
Primary and secondary forest, coastal woodland on limestone and sandstone soil, up to 2100 m alt.
Usually well-characterized by the spiral striation consisting of minute pits. Rare populations (one in Sabah) lack this striation on the teleoconch. On the protoconch, however, the pits are always present, which serves to distinguish
Shell very small, thin, translucent, yellowish brown to brown, lenticular; spire almost flat to moderately elevated, conical with a rounded apex. Surface glossy. Whorls moderately convex.
Primary and secondary forest on sandstone bedrock, up to 900 m alt., elsewhere up to 2400 m alt.
Very similar to
Most Sabah shells have a comparatively high spire.
Malaysia, Sabah, Sandakan Province, Kinabatangan Valley, Batu Keruak 2, near Sukau (
Shell very small, thin, slightly translucent, brown; inflated-lenticular to depressed-ovoid; spire (moderately) elevated (more distinctly elevated in some adults) conical with convex sides or depressed-ovoid, with a rounded apex. Surface glossy. Whorls moderately convex.
Rainforest, seasonally dry forest, coastal forest, secondary woodland; on limestone and sandstone bedrock, up to 2600 m alt.
Generally identified among Sabah
Elsewhere, the following species have a similar inflated-lenticular or depressed-ovoid shell of comparable size.
Juveniles and some adults have the basal edge of the peristome more angular than in the illustrated specimen. A small callus (not protruding beyond the rim of the peristome, as in
The name refers to the inflated shell shape [
Snails. Shell often colourful, medium-sized to very large, dextral, sinistral or chirally dimorphic, (narrowly-)conical, ellipsoid, ovoid, lenticular discoidal or globose. Sculpture absent, or inconspicuous; often with minute, geometrically arranged scars, each with a periostracal hair on top. Aperture usually without teeth or lamellae, peristome usually thickened and/or reflected. Umbilicus closed or open, narrow (Family description adapted from
Tree and rock dwellers. Widespread and species-rich throughout Southeast Asia, Australia, and Oceania.
Although the family is well-studied, and some groups have been confidently excluded because of polyphyly, such as the American taxa (Scott 1996; Wade et al. 2007),
Malaysia, Sabah, Interior Province, Pun Batu c. 30 km West of Sepulut (
Shell sinistral, rather large, rather thin but rather solid, opaque, white, top whorls with or without some oblique, pale brownish-purple markings, spire high-conical with convex sides to approx. narrowly ovoid; apex narrowly rounded. Surface shiny. Whorls: top whorls convex, other whorls slightly convex, flat or slightly concave just below the suture; last whorl rounded at the periphery, slightly convex below the periphery.
Found in shrubby forest on limestone bedrock. Alt. c. 500 m.
The small size, combined with the narrow spire uniquely identifies this species within in the genus
The name refers to the size of the shell [
The classification of this genus is still unresolved (
Malaysia, Sabah, Sandakan Province, Gunung Meliau, South flank (
Shell dextral, medium-sized, thin, opaque, whitish with 3 rather narrow, brown bands: one slightly above the periphery, one below the suture and one basal, peristome white, spire low-conical with slightly convex sides; apex almost flat. Surface dull. Periostracum rather thick, easily peeling off in dead shells, translucent, greenish-corneous, with regularly spread, short hairs. Whorls convex and not shouldered, last whorl rounded at the periphery, convex below the periphery.
Found in primary forest on ultrabasic bedrock. Alt. 600–700 m.
Uniquely identified among Sabah
This species may be endemic to the Sabah areas on ultrabasic bedrock.
The name refers that the species is found on serpentinite bedrock.
Snails. Shell small to medium-sized, dextral, conical, lenticular, or discoidal. Sculpture often rather distinct, consisting of spiral striation and/or radial ribs, sculpture sometimes inconspicuous or absent. Aperture with or without teeth or lamellae, peristome neither thickened nor reflected. Umbilicus closed or open, narrow or wide (Family description adapted from
Generally found in litter and on the vegetation. Worldwide, but particularly species-rich on the islands of and around the Pacific.
The status of several genera often included in this family, including the ones we discuss here (
The endodontid genera
We provide a review of the Sabah species of the
Shell conical to conical-ovoid, whorls somewhat depressed or not. Teleoconch: Radial sculpture prosocline, indistinct to coarse growth lines only, or with fine growth lines grading into rather densely placed, rather distinct riblets. Last whorl without spiral threads, or with 1–6 distinct spiral threads (next to a number of much finer spiral threads), the lowermost around the periphery, the others above the periphery and often interrupted. Umbilicus open, narrow, or closed.
Type of the genus is
On account of anatomical characters,
We divide the genus into two informal groups.
Malaysia, Sabah, Interior Province, Gunung Trusmadi slopes, Gua Loloposon (
Shell very small, thin, translucent to opaque, pale brown- or yellow-corneous to white, conical with flat or slightly convex sides; apex widely rounded. Surface with a silky luster.
Damp primary forest around streams, on limestone and sandstone bedrock, 500–1000 m alt.
Differs from
The name refers to the area where the species is found.
Shell very small, thin, translucent to opaque, light brown to pale yellow-corneous to white, conical with slightly convex sides, sometimes conical-ovoid; apex rounded. Surface shiny.
Primary and secondary forest, shrubby regrowth, rock outcrops, on sandstone and limestone soil, up to 600 m alt. (up to 1200 m alt. in Sarawak).
Most individuals of
Shell very small, rather thin, more or less opaque, brown, very rarely yellowish, conical with approx. flat or slightly convex sides; apex rounded. Surface about dull or with a silky luster above the periphery, glossy below.
Primary and secondary forest on limestone and sandstone soil, up to 1100 m alt.
Resembles
Indonesia, Kalimantan Timur, Sangkulirang Peninsula, Meweding Cave near village Tabalar Ulu (
Shell very small, rather thin, more or less opaque, (dark) brown, sometimes yellowish, conical with approx. flat or slightly convex sides; apex rounded. Surface about dull or with a silky luster above the periphery, glossy below.
Primary and secondary forest on limestone and sandstone soil, up to 500 m alt.
Differs from
The name refers to the shell colour [
Shell very small, very thin, translucent, pale yellow-corneous to white, conical with convex sides, to almost conical-ovoid; apex rounded. Surface glossy.
Found in damp forest on sandstone soil, at 500–1700 m alt.
Shells from Thailand (V5603, from Chiang Mai) have a slightly more distinct spiral sculpture, particularly on the lower surface, than shells from Java. The Borneo shells are intermediate in this respect.
Malaysia, Sabah, West Coast Province, Kinabalu N.P., Mesilau trail (
Shell very small, thin, hardly translucent, yellow-corneous, low-conical with slightly convex sides; apex somewhat flattened. Surface glossy.
Montane forest on sandstone soil. Alt. 2100–2400 m.
Differs from
The name refers to the absence of an umbilicus [
Malaysia, Sabah, West Coast Province, Kinabalu N.P., summit trail (
Shell very small, very thin, hardly translucent, yellowish brown, (low) conical with slightly convex sides; apex rounded. Surface with a silky luster.
Subalpine vegetation on granodiorite soil. Alt. 2900–4100 m.
Distinctly larger than
The name refers to the shell surface [
Malaysia, Sabah, West Coast Province, Kinabalu N.P., summit trail (
Shell minute, very thin, hardly translucent, pale yellow-brown, yellow-corneous below, (low-)conical with approx. flat sides; apex rounded. Surface with a silky luster.
Subalpine vegetation on granodiorite soil. Alt. 3200–4100 m.
Most similar in size and shape to
The species is named in recognition of generations of mountain guides (‘
Shell conical, with almost flat sides, with depressed whorls. Teleoconch: Radial sculpture prosocline, consisting of densely placed to moderately spaced, fine riblets. Last whorl with 2–3 distinct spiral threads (next to a number of much finer spiral threads), the lowermost around the periphery, the others above the periphery and often interrupted. Umbilicus open, narrow, or closed.
The Sabah species of
The generic position of the two species listed below is unresolved.
Shell very small, rather thin, somewhat translucent or opaque, pale brown to white, high-conical with approx. flat sides; apex rounded. Surface about dull or with a silky luster above the periphery, shiny below.
Found near a limestone cliff in logged forest, at 400–500 m alt. Elsewhere in a range of disturbed environments, drought tolerant.
The relative width of the shell shows some variability: some shells are slightly higher than wide, others are distinctly higher than wide.
Shell very small, rather thin, somewhat translucent or opaque, (pale) brown, somewhat depressed conical with approx. flat sides; apex rounded. Surface about dull or with a silky luster above the periphery, shiny below.
Found on limestone hills near the coast. Elsewhere also found in coastal environments.
More depressed conical than
The Borneo material is virtually identical with the Australian shell shown in
The species is now known from three widely distant coastal areas. It is probably a widespread element of the coastal fauna, but appears very rare. It is not an Australian endemic species, as was assumed so far.
Snails. Shell (very) small, dextral, conical, ovoid or sometimes lenticular. Sculpture inconspicuous, consisting of very fine spiral striation and/or radial riblets. Aperture without teeth or lamellae, peristome neither thickened nor reflected. Umbilicus closed, or covered by a thin callus extending from the peristome, or open, narrow (Family description adapted from Baker 1941,
Generally dwelling in litter and low vegetation. Worldwide.
Teleoconch: Radial sculpture prosocline, consisting of fine growth lines or densely placed to moderately spaced, fine riblets. Last whorl without prominent spiral threads (numerous very fine spiral threads may be present), or with 1 spiral thread or keel at the periphery.
The inclusion of the species listed below in
We provide a review of the Sabah species of
Shell very small, thin, somewhat translucent, pale brown, conical with flat sides; apex rounded. Surface shiny. Top whorls moderately convex, outer whorls slightly convex, last whorl angular at the periphery, slightly convex below the periphery.
Primary and secondary forest on limestone and sandstone soil. Alt. up to 1000 m, elsewhere up to 1700 m alt.
Information on the radula is from
Shell very small, thin, about opaque, greenish brown, (low) conical with flat or slightly convex sides; apex rounded. Surface shiny. Top whorls moderately convex, outer whorls moderately convex and somewhat shouldered, last whorl angular at the periphery, slightly convex below the periphery.
Submontane to subalpine forest on granodiorite and sandstone soil. Alt. 1200–3300 m.
Cross diagnosis: Shares the distinct sculpture of spiral threads above and below the periphery with
Shell very small, very thin, somewhat translucent, slightly brownish green, conical with flat or slightly concave sides; apex rounded. Surface shiny. Whorls slightly to moderately convex and not shouldered, last whorl angular at the periphery, slightly to moderately convex below the periphery.
Upper montane forest on granodiorite soil.Alt. 3000–3100 m.
Shell small, very thin, somewhat translucent, slightly greenish brown, conical with flat or slightly concave sides; apex rounded. Surface shiny. Whorls moderately convex and not shouldered, last whorl angular at the periphery, moderately convex below the periphery.
Subalpine forest on granodiorite soil, at 3300–3400 m alt.
Very similar to
Shell very small, thin, translucent, very pale greenish to yellowish, somewhat depressed-conical with flat sides; apex rounded. Surface shiny.
Primary and secondary forest on limestone soil. Alt. 0–500 m.
Easily recognizable within group 1 by the spiral sculpture on the teleoconch, above the periphery.
Shell small, very thin, somewhat translucent, greenish or brownish, depressed-conical with flat sides; apex rounded. Surface shiny.
Subalpine forest on diorite bedrock. Alt. 3300–3400 m.
The whorls increase faster in width than in any other Borneo
Malaysia, Sabah, Interior Province, Gunung Trusmadi slopes, Gua Loloposon (
Shell small, rather thin, somewhat translucent or opaque, pale yellow-corneous to white, depressed-conical with approx. flat or slightly convex sides; apex rounded. Surface shiny.
Primary forest on limestone and sandstone soil. Alt. c. 400–1000 m.
Differs from
The name refers to the inflated shell shape [
Malaysia, Sabah, West Coast Province, Crocker Range N.P., km 54 marker on the road Kota Kinabalu-Tambunan, Gunung Mas (
Shell small, very thin, somewhat translucent, pale yellowish-brown, somewhat depressed-conical with flat or slightly concave sides; apex rounded. Surface shiny.
Primary and secondary forest on limestone and sandstone soil. Alt. 900–1700 m.
In general shape most similar to
It differs from
The name refers to the mode of coiling [
Malaysia, Sabah, Interior Province, Gunung Trusmadi slopes, Gua Loloposon (
Shell very small, rather thin, somewhat translucent or opaque, yellow-brown corneous, depressed-conical to almost lenticular with slightly convex sides; apex rounded. Surface shiny.
Found in primary forest on limestone soil. Alt. 900–1000 m.
Uniquely identified among Sabah
The name refers to the shell shape [
Malaysia, Sabah, Interior Province, Sepulut River valley, Gua Pungiton (
Shell (very) small, thin, slightly translucent or more or less opaque, pale (yellowish) brown, conical with flat or slightly convex sides; apex rounded. Surface shiny.
Primary and secondary forest on limestone and granodiorite soil, up to 1700 m alt.
Uniquely identified by the pitted spiral sculpture on the teleoconch, in combination with its size. In
The spiral sculpture above the periphery is fine in some specimens, somewhat coarser in others. The continuous spiral striation below the periphery is absent in some specimens.
Refers to the shell sculpture [
Shell small, very thin, translucent, pale yellowish-green to pale yellowish-brown, conical with about flat sides. Surface with a silky luster, shiny below the periphery.
Primary and secondary forest on limestone and sandstone soil. Alt. up to 1000 m.
When fresh, shell thinner and more translucent than the other species in this group,
Elsewhere,
Malaysia, Sabah, West Coast Province, Crocker Range N.P., km 54 marker on the road Kota Kinabalu-Tambunan, Gunung Mas (
Shell very small, very thin, somewhat translucent, greenish-brown, conical with slightly convex sides; apex rounded. Surface with a silky luster. Top whorls convex, outer whorls only a little less convex, last whorl angular at the periphery, somewhat obtusely so near the aperture in adult specimens, moderately convex below the periphery.
Primary forest on sandstone soil. Alt. 1100–1700 m.
General shape as in
The name refers to the small size [
Shell small, rather thin, somewhat translucent or opaque, (pale) brown-corneous, (somewhat elongated) conical with almost flat or slightly convex sides; apex narrowly rounded. Surface shiny or with a silky luster.
Primary and secondary forest, rocky, vegetated roadsides, on limestone, sandstone, and granodiorite soil, up to 2200 m alt.
Incidental specimens lack the spiral thread along the periphery of the last whorl. A fine but almost continuous spiral striation may be present on the top whorls.
Shell small, rather thin, somewhat translucent or opaque, (pale) yellow-corneous to brown-corneous, (somewhat depressed) conical with convex sides; apex broadly rounded. Surface glossy or shiny.
Primary and secondary forest on limestone, sandstone and volcanic soil, up to 1400 m alt.
Adult or nearly adult shells differ from
Shell small, rather thin, somewhat translucent, (pale) brown, sometimes white, rather low-conical with flat to slightly convex sides; apex rounded. Surface with a silky luster.
Primary and secondary forest, coastal forest, at 0–1000 m alt, elsewhere to 2000 m alt.
Samples from montane environments (e.g. Poring Hot Springs,
Information on the radula is from
Shell small, very thin, somewhat translucent, (yellowish) brown, rather low-conical with flat sides; apex rounded. Surface shiny.
Montane and sub-alpine forest on granodiorite and sandstone soil, at 1600–3400 m alt.
In general shape, sculpture and mode of coiling very similar to
Juveniles of
We depict a keeled, juvenile specimen with approx. 1 whorl less than the type specimen, which does not have a keel. The sculpture and general shape is similar in both specimens.
The Gunung Trusmadi record is based on a shell consisting of hardly more than a protoconch. Its identity is somewhat uncertain.
Shell small, rather thin, slightly translucent or opaque, (pale) brown, rather low-conical with approx. flat sides; apex broadly rounded. Surface with a silky luster. Whorls (moderately) convex, last whorl rounded at the periphery (somewhat angular in juveniles), rounded above and below the periphery.
Primary forest, secondary forest and coastal forest on limestone bedrock and volcanic bedrock; all localities in the lowlands.
Shell shape similar to
Teleoconch: Radial sculpture approx. orthocline, consisting of widely spaced, coarse ribs. Last whorl with 1 spiral thread near the periphery.
The genus
Malaysia, Sabah, Sandakan Province, Kinabatangan valley, Batu Pangi (
Shell small, rather solid, somewhat translucent to opaque, (pale) brown, conical with convex sides to almost ovoid; apex rounded. Surface shiny.
Primary and secondary forest on limestone soil, up to 500 m alt.
Differs from
All continental Asiatic species of
The name refers to the sculpture [
Shell very small, dextral, lenticular or discoid. Sculpture consisting of inconspicuous radial riblets, spiral sculpture subordinate. Aperture without teeth or lamellae, peristome usually thin and not reflected. Umbilicus open, narrow or wide (Family description adapted from
Soil and litter dwellers. Widely distributed in Africa, Europe, Asia, and Australia.
The family is poorly known and although many genera and species have been described, the true diversity may consist of a smaller number of widespread, regionally variable species.
Sabah
Malaysia, Sabah, West Coast Province, Crocker Range, Kiansom Waterfall (
Shell minute, thin, slightly translucent, yellowish brown, low-conical to lenticular, apex rounded. Surface shiny.
Secondary forest on sandstone hills, lowland conditions.
Characterized within the genus by the narrow umbilicus, the presence of radial riblets on the protoconch, and the distinct and widely spaced spiral sculpture on the lower surface.
The name refers the the narrow umbilicus [
Snails. Shell small to very large, dextral (rarely sinistral), narrowly conical to cylindrical and more or less tapering towards the apex. Sculpture absent, or inconspicuous, radial riblets with usually subordinate spiral striation; rarely spiral keels present. Aperture without teeth or lamellae, peristome thin, not reflected. Umbilicus closed or open, narrow (Family description adapted from on
Scavengers of soil and litter. Globally distributed in the tropics and subtropics.
The generic and specific classification of the
Malaysia, Sabah, Tawau Province, Danum Valley Conservation Area, 2 km NW of Research Station (leg. H.A. Rutjes,
Shell small, thin, slightly translucent, white, subcylindrical, only slightly tapering towards the apex, with slightly convex sides. Surface glossy.
Primary and secondary forest on limestone, also on other types of bedrock. Alt. 0–400 m.
Among Borneo
The name refers to the general shape of the shell [
Snails, rarely semi-slugs. Shell medium-sized to very large, dextral or sinistral, (low-)conical, to lenticular or discoid. Sculpture usually inconspicuous to distinct, fine spiral striation and/or radial riblets; in some species coarser sculpture is present, for instance spiral ridges or nodular structures on the intersection of spiral and radial sculpture. Aperture without teeth or lamellae, peristome thin or thick, reflected or not. Umbilicus closed or open, narrow (Family description adapted from Baker 1941;
Most species are found on understorey vegetation. Widely distributed in Southeast Asia and Oceania.
The genera reviewed are
Generally, the two genera include species with conical shells, not unlike
Shell rather small to medium-sized, (pale) yellowish green to (yellowish) brown, without any colour patterns, or with lighter or darker streaks following the growth lines; low-conical with flat or slightly convex sides, apex protruding or not. Radial sculpture above the periphery distinct, consisting of riblets or irregularly spaced, raised growth lines locally causing a coarse, irregular wrinkling. Spiral sculpture distinct, consisting of threads which are highest or nodular where crossing the radial sculpture, lower or even absent elsewhere. Umbilicus closed, entirely covered by an extension of the parietal callus of the peristome.
Shares the closed umbilicus with Borneo
Possibly, the protoconch with radial riblets can be added to the diagnostic set distinguishing between Borneo
We provide a review of the Sabah species of
Malaysia, Sabah, West Coast Province, Crocker Range N.P., near the km 54 marker on the road Kota Kinabalu-Tambunan, Gunung Mas (leg. J.J. Vermeulen & M. Schilthuizen,
Shell rather small, thin, opaque, reddish brown with darker brown or whitish streaks following growth lines, slightly paler brown with similar darker streaks below the suture, conical with flat sides; apex not protruding. Surface dull or slightly shiny above the periphery, glossy below.
Mixed montane forest, c. 1400 m alt.
Uniquely identified by the very coarse, at irregular intervals interrupted spiral sculpture.
The material seen is probably sub-adult, and has the apex damaged. The description of the apex and the peristome will need amendation once more material becomes available.
The name refers to the shell surface [
Shell rather small, rather thin, about opaque, (pale) yellowish brown to pale greenish brown, moderately low-conical with approx. flat sides; apex not protruding. Surface with a silky luster above the periphery, shiny below.
Montane and sub-alpine forest on sandstone and granodiorite bedrock, 2400–3300 m alt.
See under
Malaysia, Sabah, West Coast Province, Kinabalu N.P., near Summit trail (leg. T.S. Liew et al.,
Shell medium-sized, rather thin, about opaque, yellowish brown, moderately low-conical with somewhat convex sides; apex slightly protruding. Surface with a silky luster above the periphery, shiny below.
Montane and sub-alpine forest on sandstone bedrock, 1900–3300 m alt.
Consistently larger than
The name refers to the knotted shell surface [
Malaysia, Sabah, West Coast Province, Kinabalu N.P., near Summit trail (leg. T.S. Liew et al.,
Shell rather small, rather thin, about opaque, yellowish brown, low-conical with somewhat convex sides; apex protruding. Surface with a silky luster above the periphery, shiny below.
Montane forest on sandstone bedrock, 1900-2300 m alt.
Similar to
The only available shell is a juvenile with the last 1/8 whorl broken. The description needs to be amended once more material becomes available.
The name refers to the protruding apex [
Shell rather small to medium-sized, (pale) corneous to (yellowish) brown, without any colour patterns, or with brown spiral bands (
We provide a review of the Sabah species of
Kudat Province. Balambangan Island, Kok Simpul (leg. J.J. Vermeulen & M. Schilthuizen,
Shell medium-sized, rather thin, opaque, uniformly pale yellowish brown, low-conical with flat to slightly convex sides; apex not protruding or only slightly so. Surface with a silky luster above the periphery, shiny below.
Dry primary lowland forest, coastal forest on limestone soil.
Characterized by the combination of lack of spiral colour bands, the not-pinched periphery, the moderately convex whorls and lower surface of the shell.
A group of very similar species, distinguished here on account of shell colour, aperture shape and the position of the peripheral keel relative to the shell height. Anatomical and molecular investigation is needed to further unravel the taxonomical structure of the group.
Shell medium-sized, rather thin, opaque, creamy white, greyish very pale yellowish brown, periphery whitish, with a narrow, rather vaguely outlined, pale to dark (ochre-)brown band immediately above it, and often a second, similar band immediately below it, shell low-conical with approx. flat sides, apex not or hardly protruding. Surface shiny.
Primary and secondary forest on limestone soil. Lives on decaying wood.
Differs mainly from
Shell medium-sized, rather thin, opaque, brown, sometimes a slightly paler brown just below the suture, periphery pale brown to dull white; shell low-conical with approx. flat sides, apex not or hardly protruding. Surface with a silky luster above the periphery, shiny below.
Primary and secondary forest on sandstone and shale bedrock, 600–2800 m alt. Lives on decaying wood.
See under
The exact morphology of a very fine radial wrinkling of the supra-peripheral part of the shell needs to be investigated.
Malaysia, Sabah, West Coast Province, Kinabalu N.P., Headquarters area (leg. M. Schilthuizen,
Shell medium-sized, rather thin, opaque, uniformly somewhat pale brown, periphery pale brown; shell low-conical with approx. flat or slightly concave sides, apex not or hardly protruding. Surface with a silky luster above the periphery, shiny below.
Forest on sandstone or limestone soil, also found in grassy roadside with forest nearby, alt. 900–2200 m.
See under
The name refers to the convex lower side of the shell [
Shell medium-sized, rather thin, opaque, uniformly pale to dark brown (some material from Sarawak a paler brown just below the suture), (low-)conical with almost flat to distinctly concave sides, apex slightly to distinctly protruding. Surface more or less dull or with a silky luster above the periphery, shiny below.
Primary and old secondary forest on sandstone and volcanic bedrock, lowland conditions. Living on decaying wood.
Generally characterized by the conical spire, but low-conical specimens occur. These approach the
See also the remarks under
Malaysia, Sabah, West Coast Province, Crocker Range N.P., Ulu Kimanis, along Keningau-Kimanis road (
Shell medium-sized, rather thin, opaque, above the periphery greyish with a somewhat vaguely outlined brown band just above the peripheral keel, and with an irregular pattern of white stains and spots which more or less follow the radial and spiral sculpture, periphery white, below the periphery dark brown, grading to white towards the periphery; shell conical with convex sides; apex not protruding. Surface shiny above the periphery, glossy below.
Disturbed primary forest on sandstone bedrock, c. 1400 m alt.
Uniquely identified within
The only shell available is possibly sub-adult. The description of the aperture may need to be amended once more material becomes available.
The pattern of low, vaguely outlined spiral ridges and similar rows of oblique indentations do not occur in any other
The name refers to the dirty white apiral band [
Malaysia, Sabah, Tawau Province, Tawau Hills N.P. (leg. J.P. King,
Shell medium-sized, rather thin, about opaque, brown, above the periphery with a very fine, slightly paler spiral striation, high-conical with concave sides; apex protruding. Surface slightly shiny above the periphery, glossy below.
Forest on sandstone or volcanic soil, lowland conditions.
Uniquely identified within
The name refers to the shape of the spire [
Malaysia, Sabah, West Coast Province, Kinabalu N.P., Headquarters area, Silau Silau (leg. K. Kittel,
Shell rather small, rather thin, about opaque, yellowish brown, whorls slightly darker brown towards the periphery, moderately low-conical with approx. flat sides; apex not protruding. Surface dull or slightly shiny above the periphery, shiny below.
Mixed montane forest, 1500–1800 m alt.
In size and general shape most similar to
The single shell available is somewhat worn in the apical region. Traces of what may be radial riblets are present in the suture of the protoconch, close to the transition to the teleoconch.
Named after Mr. Klaus Kittel, Germany, who collected the type specimen.
Shell rather small, rather thin, about opaque, pale corneous to pale brown, low-conical with approx. flat sides; apex not protruding. Surface with a silky luster above the periphery, shiny below.
Mixed montane forest, 700–2100 m alt.
Malaysia, Sabah,
Sandakan Province. Kinabatangan valley, Batu Mawas (leg. T.S. Liew & M. Schilthuizen,
Shell rather small, rather thin, about opaque, yellowish to pale brown, moderately low-conical with slightly concave to slightly convex sides; apex slightly to moderately protruding. Surface with a silky luster.
Primary and secondary forest and more degraded vegetation types on limestone soil, up to 200 m alt.
Most similar to
The name refers to the slightly protruding peripheral keel, creating a small notch in between the whorls in lateral view [
Malaysia, Sabah, Interior Province, Sepulut valley, Batu Punggul (leg. J.J. Vermeulen,
Shell rather small, rather thin, about opaque, yellowish to pale brown, moderately low-conical with flat to slightly convex sides; apex slightly protruding or not. Surface with a silky luster.
Primary, secondary forest and abandoned agricultural land on limestone and sandstone soil, up to 1300 m alt.
Shell less wide than
The name refers to the slightly protruding peripheral keel, creating a small notch in between the whorls in lateral view [
We are greatly indebted to John Ablett (