Glyphyalinia indentata paucilirata, copyright Jason M. Crockwell.

Belongs within: Limacoidei.

Glyphyalinia snails
Published 29 May 2022

North America (as with pretty much everywhere in the world outside the coldest regions) is home to a wide diversity of small, terrestrial snails that tend to pass unnoticed. Among the more diverse of these is the zonitid genus Glyphyalinia.

Glyphyalinia carolinensis, copyright John Slapcinsky.

Glyphyalinia species are often found in forest leaf-litter in the eastern part of North America. They have a low, translucent shell that is often about half a centimetre in diameter. Whorls of the shell increase regularly in size and are marked by a series of strongly impressed radiating lines in addition to finer growth lines. The umbilicus of the shell varies between species from completely absent to quite wide (Burch & Pearce 1990). The soft body of the animal varies in coloration, again depending on species. That of G. roemeri is all white except for the eyes; that of G. wheatleyi is almost uniformly black. The reproductive system of Glyphyalinia (which are hermaphroditic) includes a well-developed epiphallus and a distinct, ovoid spermathecal sac (Baker 1930).

Multiple species of Glyphyalinia may be found living in a single patch of forest though, at present, we know little about how (and whether) micro-habitats are partitioned between species. Some species seem to tolerate a wide variety of soil types and are correspondingly widely distributed. Others are more selective and localised; some may be considered endangered by habitat degradation. Even supposedly widespread species may be more vulnerable than appreciated: at least some may represent clusters of closely related species rather than truly uniform populations. These tiny snails can be notoriously difficult to study, making for a risk that they might just slip away barely noticed.

Systematics of Glyphyalinia
<==Glyphyalinia Martens 1892BP90
|--G. clingmaniBP90
|--G. cryptomphalaH65b
|--G. cumberlandianaH65b
|--G. floridanaH63
|--G. indentataBP90
| |--G. i. indentataBP90
| `--G. i. paucilirataBP90 [=Retinella (Glyphyalinia) indentata paucilirataH65b]
|--G. lewisianaH68
|--G. luticola Hubricht 1966H66
|--G. pecki Hubricht 1966H66
|--G. praecoxH68
|--G. raderiBP90
|--G. rhoadsiBP90
|--G. roanensis (Baker 1930) [=Retinella (Glyphyalis) cumberlandiana roanensis]H65b
|--G. sculptilis [incl. Retinella (Glyphyalinia) sculptilis subdola Baker 1930]H65b
|--G. solida (Baker 1930) [=Retinella (Glyphyalinia) cryptomphala solida]H65b
|--G. specus Hubricht 1965H65a
|--G. virginicaBP90
`--G. wheatleyiH68

*Type species of generic name indicated


Baker, H. B. 1930. The North American Retinellae. Proceedings of the Academy of Natural Sciences of Philadelphia 82: 193–219.

[BP90] Burch, J. B., & T. A. Pearce. 1990. Terrestrial Gastropoda. In: Dindal, D. L. (ed.) Soil Biology Guide pp. 201–309. John Wiley & Sones: New York.

[H63] Hubricht, L. 1963. Some Succineidae, with a new species. Nautilus 76 (4): 135–138.

[H65a] Hubricht, L. 1965a. Four new land snails from the southeastern United States. Nautilus 79 (1): 4–7.

[H65b] Hubricht, L. 1965b. Notes on Zonitidae. Nautilus 78 (4): 133–135.

[H66] Hubricht, L. 1966. Four new land snails. Nautilus 80 (2): 53–56.

[H68] Hubricht, L. 1968. The land snails of Mammoth Cave National Park, Kentucky. Nautilus 82 (1): 24–28.

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