Table 2 (continued on next page). Comparison of conchological characters of all species of Acmella W.T. Blanford, 1869 from India and Myanmar.CharactersA. bensoni sp. nov.A. tersa W.H. Benson, 1853A. mellilla Godwin-Austen, 1895A. moreletiana G. Nevill, 1878A. roepstorffiana G. Nevill, 1878A. hyalina Theobald & Stoliczka, 1872Size (SH × SW) (in mm)1.22–1.37 × 1.03–1.092.14–2.38 × 1.45–1.661.75 ×1.252 × 1.331.5 × 11 × 0.7Shell shapeconical-oval, turbinate, shiny and somewhat transparent, and depressedtypical assimineid (conical to ovoid), somewhat semi-transparentovately turreted, somewhat semi-transparentconical-turreted, hyaline/ glossy, transparent, polished, and shiningconico-turrited, shining, translucent, silkyovately conical, hyalineColorwhitebrownish corneouspale umberwhite–dirty whitishUmbilicusopen and widenarrow, nearly closedwidely openwidely openopenmoderately perforatedWhorls4.25–4.5, convex4.5–5, convex5–5.5, sides flat5, highly convex, last whorl globular, convex below5, slightly convex whorls, gradate, last whorl subcylindrical, slightly compressed at periphery, convex beneath4.5, somewhat convexLirationindistinct, fine and densely spaced spiral and radial ribs or growth lines across shell surface, fine radial ribs clearly visible on neck of apertureprotoconch finely granulose, teleoconch with irregular, rather strong, somewhat wavy ribs, some of which may convergesculpture oblique, fine, close costulation, radially ribbed across shell, very densed and overlapped at aperture necksculptured round umbilicus in very characteristic manner, with regular distinct plications, beneath suture, faint striation is discernible, with lensentirely distinct, somewhat strongly, closely, evenly or regularly striated; striae thread-like, oblique, more prominent toward base, especially around umbilical regionsmoothSpireacuminateacuminatedepressedly conicdepressedly conicalacuminatebluntApexconicalconicalvery bluntbluntblunt and conicalconicalSuturemoderate to well-impressed with slightly extended shoulderwell-impressedimpressedwell-impressedwell-impressedsimple and deep sutureApertureovate-lunate, oblique or sub-verticalprosocline, only slightly oblique to shell axis from lateral view, elongate ovoid with pointed parieto-palatal angleoval, subobliqueperfectly rounded, margins closely approximated but not continuousvery small, subcircular, with margins almost but not continuous, columellar one being abruptly bent back over umbilicus and then beautifully and boldy roundedregularly ovate, above (or posteriorly) somewhat angled, not obliquePeristomesimple, somewhat thick and continuous, parietal lip straight, sometimes indistinct, merged with body-whorl, parieto-palatal juncture distinct and sharply angulated, palatal, basal and columellar lips or edges roundishsharp, not expandeddouble, with strong callus on body whorlslightly thickened, columellar margin gradually rounded, not covering the umbilicus.thickened, not continuous, externally slightly expanded; columellar margin strongly arched, more or less covering the umbilicusthin, almost continuousOperculumunknownhorny, extremely thin, paucispiralunknownunknownunknownabsent?Habitatboth dry and wet walls of cave, approximately 4–12 m from cave entrancemoss in foresttropical rainforesttropical rainforestmidddy coastal areaon limestone hillsDistributionKrem Puri, Meghalaya, India; Arwah Cave, Meghalaya, IndiaMawsmai Cave, Musmai (= Mawsmai) near Cherrapunji (= Cherrapunjee), Meghalaya, IndiaSouth Andaman, IndiaBatti Malve, Nicobar Islands, IndiaKatchall, Nicobar Islands, IndiaSouth of Moulmein, Myanmar