Leptopoma trochus Dohrn, 1862
“This species has a considerable resemblance to L. undatum, Metcalfe, and L. niahense, Godwin-Austen. It is at once distinguished from the latter by the absence of the constriction behind the labrum, the double peristome, the almost concealed umbilicus, the more convex whorls, and slightly finer sculpture. L. undatum also has the body-whorl constricted behind the lip, but the peripherial keel becomes obsolete a little from it, so that in the present species and L. niahensis. L. undatum is more openly umbilicated and has not a double peristome.” (E. A. Smith, 1895)
E. A. Smith (1895) original descriptions on Leptopoma geotrochiforme - “Testa fere obtecte perforate, trochoidea, ad peripheriam acute carinata, subtus planiuscula, alba; spira conica, acuta; anfractus 6, celeriter crescents, leviter convexi, spiraliter tenuiter striate, lineisque incrementi obliquis, flexuosis, tenuissimis sculpti, ultimus supra et infra carinam concave compressus, antice haud descendens; aperture subcircularis; peristoma duplex, margine externo tenui expanso, ad angulum acuminato, latiore supra quam infra, interno continuo, paulo incrassato.”
Kobelt (1902) descriptions on Leptopoma (Trocholeptopoma) geotrochiforme – “Schale fast bedeckt genabelt, kreiseiförmig, scharf gekielt, unten fast flach, weiss; Gewinde kegelförmig, Apex spitz; 6 rasch zunehmende, leicht gewölbte Windungen, fein bogig gestreift und mit sehr feinen Spirallinien, letzte über und unter dem Kiel konkav eingedrückt, vorn nicht herabsteigend; Mündung fast kreisrund; Mundrand doppelt: innerer zusammenhängend, wenig verdickt, äusserer dünn, ausgebreitet, an der Kante zugespitzt, oben breiter als unten.”
Vermeulen (1999) descriptions on Leptopoma trochus – “Shell white, with or without translucent banding parallel to the growth lines. Whorls 5 ¼-5 5/8, the first few moderately convex, the others almost flat to slightly convex, but the last also slightly to moderately concave towards the periphery with a istinct keel that continues up to the peristome. Suture moderately depressed between the first whorls, elsewhere slightly depressed. Spiral sculpture; a fine striation, often combined with 3-5 slightly raised, inconspicuous ridgelets. Umbilicus narrow, largely or entirely covered by the peristome. Peristome white, on the palatal side usually slightly thickened and abruptly reflected, with a distinct lip that gradually increases in height towards the angular edge and then continues on the parietal side as a somewhat lower lip again.”
Leptopoma geotrochiforme – “Diam. Maj. 22 millim., min. 17, alt. 20; apertura intus 9 longa, 9 ½ lata.” (E. A. Smith, 1895); Leptopoma undatum – “Height 15-19.5 mm, width 17-22 mm; height aperture 5.5-9.5 mm, width 9-12 mm.” (Vermeulen, 1999)
Type locality – Leptopoma geotrochiforme “Mount Rabong, West Sarawak” (E. A. Smith, 1895)
Other localities – “Kpg. Tiang Bekap, 10 km S.S.W. of Kpg. Beratok” leg. De Vogel (Vermeulen, 1999)