Diplommatina diminuta von Moellendorff, 1891
“Stated shortly the points in which this species differs most from diminuta Mllff. are shape and armature of aperture and the much smaller number of costulations.” (Tomlin, 1938)
Möllendorff (1891) original descriptions on Diplommatina diminuta – “T.sinistrorsa, vix rimata, gracilis, turrita, corneo-flavescens: spira turrito-conica, apice obtusiusculo brunnescente. Anfr. 7½, perconvexi, medio subangulati, oblique costulato-striati, 2 ultimi paullum distorti, ultimus penultimo angustior, initio constrictus, tum inflatulus, antice ascendens. Apertura parum obliqua, angulato-subcircularis; peristoma duplex, externum campanulatum, expansum, internum sat porrectum, expansiusculum, margine columellari cum basali angulum subacutum formante. Lamella columellaris modica, obliqua, palatalis longiuscula, supra rimam tranlucens.”
Kobelt (1902) descriptions on Diplommatina (Sinica) diminuta – “Schale linksgewunden, kaum geritzt, schlank getürmt, mit schrägen Rippenstreifen, gelblich hornfarben; Gewinde getürmt kegelförmig, Apex ziemlich stumpf, braun; 7½ sehr gewölbte, in der Mitte schwach kantigen Windungen, die 2 letzten leicht verdreht, letzte schmaler als die vorletzte, am Beginn eingeschnürt, dann leicht aufgeblasen, vorn ansteigend; Mündung wenig schi'äg, eckig kreisrund; Mundrand doppelt: äusserer glockenförmig erweitert, ausgebreitet, innerer ziemlich vorgezogen, leicht ausgebreitet, am unteren Ende der Spindel ziemlich spitzwinkelig; Spindelfalte massig stark, schief, Gaumenfalte ziemlich lang, über der Nabelgegend durchscheinend.”
Tomlin (1938) original descriptions on Diplommatina (Sinica) sinistra – “About the same size as, and superficially similar to D. (Sinica) diminuta Moellendorff from Bukit Pondong: it is minute, sinistral, has 7 ½ whorls which are convex, with deeply impressed sutures, the penultimate whorl being broader and rather more dilated than the ultimate; it has about twenty-four axial costulations on the penultimate whorl and a deep-seated columella tooth, but lacks parietal and palatal teeth; the number of costulations in diminuta is not stated but must be, from the figure, many more than this; aperture in sinistra irregularly rounded except that on the right-hand side the peristome is almost straight from its junction with the body whorl, forming a chord to the irregular are of the rest of the peristome.”
Laidlaw (1949) descriptions on Diplommatina diminuta – “Shell fusiform, of about 7 ½ whorls, the penultimate rather broader and more inflated than the last. About 24 ribs on the penultimate whorl. Mouth nearly vertical, rounded, but the columellar limb less strongly curved than the rest. Peristome very little expanded; columellar tooth prominent.”
Diplommatina diminuta – “Longit. 2, diam. max. 0.9 mm.” (Möllendorff, 1891); Diplommatina (Sinica) diminuta – “H. 2, Durchm. 0.9 mm.” (Kobelt, 1902); Diplommatina (Sinica) sinistra – “Long., 1.9 mm.; diam. max., 1 mm.” (Tomlin, 1938); Diplommatina diminuta – “Length 2 mm. Breadth max. 0.95 mm.” (Laidlaw, 1949); Diplommatina sinistra – “Length 1.9 mm. Breadth max. 1 mm.” (Laidlaw, 1949)
Type locality – “Bukit Pondong” leg. R. Hungerford (Möllendorff, 1891); Diplommatina (Sinica) sinistra “Sungei Siput, Perak” leg. M. W. F. Tweedie (Tomlin, 1938)