> Lyogyrus latus Thompson & Hershler 1991
 

> Habitat & Distribution
Lyogyrus latus is widespread in the main stem and some larger tributaries of the Ogeechee River.  The FLMNH also contains single records of the species from the Altamaha River, and from a tributary of the Flint River in western Georgia, which imply that the range of L. latus may ultimately be found to include most of the larger rivers of the Georgia coastal plain.  Thompson & Hershler (1991) describe its microhabitat as cryptic, "on the underside of chert and sandstone cobbles and boulders in riffles."
   

> Ecology & Life history
Thompson & Hershler, in their original description of L. latus, characterized its behavior as "secretive," possibly nocturnal.  No specific life history data are presently available for L. latus, but Jokinen (1983) reported an annual life cycle for a population of Lyogyrus granum in Connecticut. 

> Taxonomy & Systematics
The genus Lyogyrus is in the hydrobiid subfamily Amnicolinae, characterized by a doubly-ducted penis.  For many years the taxon was considered a subgenus of Amnicola, but Thompson & Hershler (1991), in their description of L. latus, raised Lyogyrus to the genus level. 

> Map of Lyogyrus distribution (PDF)


> References
Jokinen, E. H. (1983)  The freshwater snails of Connecticut.  State Dept of Environmental Protection Bulletin 109, 83 pp.  Kabat, A.R., and R. Hershler (1993) The prosobranch snail family Hydrobiidae (Gastropoda: Rissooidea): review of classification and supraspecific taxa. Smithsonian Contributions to Zoology 547:1-94. Thompson, F. G. (1968)  The aquatic snails of the family Hydrobiidae of peninsular Florida.  University of Florida Press, Gainesville.  268 pp.  Thompson, F. G. & R. Hershler (1991)  Two new hydrobiid snails (Amnicolinae) from Florida and Georgia, with a discussion of the biogeography of freshwater gastropods of south Georgia streams.  Malac. Rev. 24: 55-72.    Thompson, F.G. (2004)  An identification manual for the freshwater snails of Florida.