Glyphyalinia - Glyph Snails (Family Zonitidae)
a Glyph Snail with mm scale
The Glyph Snails (Glyphyalinia) have an interesting shell. The whorls are loosely coiled and the past whorl, especially, expands greatly. The shell is glossy and the surface has noticeable radial indented lines (transverse striae). The expansion of the last whorl and the indented lines serve to separate this genus from most others.
Two species are most likely common in suitable habitat across the state – the Carved Glyph Snail (Glyphyalinia indentata) and the Bright Glyph Snail (Glyphyalinia wheatleyi). These two species look very much alike except that the umbilicus is perforate in the Carved Glyph, but umbilicate in the Bright Glyph. The distinct indented radial lines are equally and widely spaced are common as is ever-increasing whorls size seem from above. Six other species may be found in the state, rarely, but their status is uncertain. These are described below.
Key for the two most likely species:
umbilicate - Glyphyalinia wheatleyi
perforate (to rimate) - Glyphyalinia indentata
Glyphyalinia indentata (Say, 1823) with mm scale
Glyphyalinia indentata (Say, 1823)
Characteristics: umbilicus perforate to rimate, very glossy surface, distinct indented radial lines are equally and widely spaced, aperture not reflected, faint growth lines and fine spiral striae; 4.7-7.1 mm in diameter; 4.5-5 whorls. Distinguished from the Bright Glyph and Thin Glyph by its perforate to rimate umbilicus.
Habitat: under leaf litter in mixed hardwood forests, from mesic to xeric habitats, riverside bluffs, moist leaf litter and soil, prairies, glades, and perhaps along roadsides and in urban areas
Status: Widely distributed in the state in suitable habitat.
Bright Glyph Snail
Glyphyalinia wheatleyi (Bland, 1883)
Characteristics: umbilicus wide and ovalish, very glossy surface, distinct indented radial lines are equally and widely spaced, aperture not reflected, fine spiral striae may be weak or absent; 5-5.5 mm in diameter;
5-5.5 whorls. Distinguished from the Carved Glyph and Thin Glyph by its umbilicus.
Habitat: under moist conditions in leaf litter and deeper detritus in mixed hardwood forests, including hillsides and ravines.
Status: Less widely distributed than the Carved Glyph, in scattered counties in suitable habitat.
Other Potential Species
The other six species are, if they really exist in the state at all, rare. They fall into three groups.
Species in the first group have both museum records and listing in NatureServe. They are Glyphyalinia cryptomphala, Thin Glyph Snail; Glyphyalinia rimula, Tongued Glyph Snail; and Glyphyalinia solida, Imperforate Glyph Snail. These two species are the most likely of this grop of six to actually exist in the state (if true species - note the comments above on this genus).
Species in the second group are listed in NatureServe but have no museum records (at the time of accessing the data): Glyphyalinia latebricola, and Glyphyalinia lewisiana - neither have common names I could find.
One species is in the final group - Glyphyalinia umbilicate, Texas Glyph Snail, with one record in the databases but not listed in NatureServe where is a distinctly southen species. This is most likely a mis-identfied specimen.
Four of these have Indiana locations in the databases, but the records are very few (one species is not listed for Indiana in NatureServe). Two further species are listed in Nature Serve, but there are no records of them in the databases as accessed for this project. Echoing Dourson (2015), this genus “can be a troublesome group of land snails for the novice. Even for the experienced malcologist, they are challenging.” More on this genus can be found there. As well, Hotopp et al. (2013) note that “Hubricht (1985) reported variation in genital anatomy within Glyphyalinia indentata and he suggested the species is a complex of several species with similar shells. Therefore, our current understanding of this species’ range and habitat requirements are probably far too general. Accurate conservation rank assessments must await taxonomic study and clarification of the complex.”