“This species is a trifle less robust than Opisthostoma jucundum, much more closely lamellated, has a more expanded peristome, and a distinct basal crest or ridge upon the body whorl.” (E. A. Smith, 1894) “The keel-like crest upon the lower part of the body-whorl commences where the whorl is constricted and its irregular contortion commences. The oblique lamellae are excessively slender, like the finest threads, and slightly wavy at the periphery. There are about eighteen upon the penultimate whorl. The outer margin of the peristome is rather narrow, not expanded like the inner edge, and interrupted on the right side, or that towards the spire, as is the case also in some other species.” (E. A. Smith, 1905)

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