Rhinocochlis nasuta (Metcalfe, 1851)
“This elegant species is covered with a thin epidermis, of a pale straw colour, under which the shell is milky white. It bears some analogy to H. tayloriana (Adams and Reeve, Zool. Of the Samarang, Mollusca, pl. 15. Fig. 2 a,b), but the projection at the extremity of the aperture is much more acute, and the shell is of a more gelatinous texture: it differs also in being sinistral.” (Metcalfe, 1851)
“A few specimens, the largest of which measures only 24 mill, instead of 35, as is mentioned by the author; having also a whorl less, it may be a young one, though the projection of the aperture is already faintly marked. The specimens are too little in number, to describe a new variety upon, which will probably prove to be desirable when more material is at hand.” (Schepman, 1896)
“Ein Exemplar vom Baram ist erheblich kleiner, als der Typus (36 mm), deutlich, wenn auch etwas überdeckt, durchbohrt, und obenher mit einigen deutlichen, wenn auch, schwachen Spiralreifen; die feine Spiralskulptur ist besonders auf der Unterseite gut entwickelt, einige stärkere, schon dem blofsen Auge autfallende Furchen stehen im ersten Viertel der Unterseite nahe dem Kiel.” (Kobelt, 1897)
“Samarinda, ein junges Exemplar von drei Umgängen, nur 14 mm im großen Durchmesser, glänzend gelb, das nach der ganz flachen Oberseite und deren schwacher Skulptur, sowie dem sehr scharfen Kiel zu dieser Art gehören dürfte.” (Martens, 1908)
Metcalfe (1851) original descriptions on Helix nasuta – “H. testâ subdiscoideâ, sinistrorsâ, carinatâ, angustè perforatâ, tenuissimâ, lineis incrementi et spiralibus confertis subtilissimè decussatâ, pellucidâ, hyalinâ; lineâ angustâ pallidè brunneâ ad carinam ornatâ; spirâ subconica; anfractibus 5½ planulatis, ultimo acutissimè carinato, subtus nitescente; aperture subrhomboideâ, ad angulum exteriorem valdè productâ et coarctata; peristomate simplici, tenui, margine superior vix reflexo, basali anticè reflexiore, umbilicum subtengente.”
Kobelt (1897) descriptions on Dyakia nasuta – “Testa sinistrorsa, subobtecte perforata, depressa, tenuissima, acutissime carinata, oblique striata, lineis spiralibus subtilissimis sub lente minutissime decussata lirisque nonnullis fortioribus superne sculpta, pallidissime corneo-virens. Spira breviter conoidea apice acutiusculo. Anfractus 5½, superi plani vel vix convexiusculi, ultimus prope suturam planatus, dein convexiusculus, ad carinam acutam utrinque compressus, basi convexior, circa umbilicum subgibbus, antice band descendens, ad carinam in rostrum acuminatum productus. Apertura perobliqua, elongato-triangularis, intus concolor, profunde canaliculata; peristoma tenue, undique breviter expansum, marginibus haud junctis, supero stricto, basali rotundato, columellari superne brevissime retlexo.”
“One specimen of this very remarkable and beautiful shell was preserved in spirit. Animal pale-coloured, like that of D. hugonis; the mucous gland has a very small overhanging lobe and a broad pallial margin. The odontophore has the central tooth tricuspid, the central cusp hardly rising above those on either side; the median are square at the end, bicuspid, the laterals have a sharp inner cusp and a rounded outer cusp, rising close together; the outermost laterals are unicuspid and small: (+ 70 . 14 . 1 . 14 . 70 +) and (+ 80 . 1 .80 +.) Some of the small outermost teeth were lost in dissection. The generative organs are similar to those of D. hugonis and do not require any further description. It would be difficult to select two shells differing so much in form as D. hugonis and D. nasuta; any classification based on shell characters would place them widely apart, yet the animals as regards their structure are closely allied. This points to a long occupation of this island by this group of land-shells.” (Godwin-Austen, 1891)
Helix nasuta – “Long. 1 4/10; lat. 1 1/10; alt. 5/10 unc.” (Metcalfe, 1851); Dyakia nasuta - “Diam. maj. 31, min. 24, alt. 12 mm.” (Kobelt, 1897)
Type locality – “Borneo” leg. W. J. Hamilton/Nov. 1850 (Metcalfe, 1851)
Other localities – “Come sopra” leg. Doria and Beccari (Issel, 1874); “Niah Hills” (Godwin-Austen, 1891); “Top of Mount Klam near Sintang” leg. Hallier/Jan. 1894 (Schepman, 1896); ”Baram” (Kobelt, 1897); “Sungei Guleh, Sangkulirang” (Martens, 1908)