Key to spp.: Galley (1999)
"Please note that Selonodon is one of those exceptionally difficult genera. Despite the fact that there is a nice modern revision, things still don’t seem to make complete sense in Texas, probably because of the lack of specimens from many critical places. I’ve just about given up trying to understand the Texas species, as I have several “species” from Texas that don’t seem to be in Galley’s revision. ...
Females are flightless – and this always seems to be linked to problems in alpha taxonomy, as specimens seem to be a little different among various locations. If there was ever a genus where you could ID the species by locality, this is it, just look at most of Galley’s distribution maps.
Another complicating factor is that most adult activity seems to be during and immediately after big rainstorms, thus they can not always be collected simply by visiting a known location –or certainly not collected in the lengthy series needed to help understand their taxonomy. One’s collecting trip needs to coincide with the correct weather event.
To work out the taxonomy of this genus in Texas would be a lofty goal, and would require a lot of serious targeted field work year after year. A thorough working knowledge of the geology of Texas surface soils would probably be essential." (E.G. Riley, pers. comm., 2010)
Galley K.E.M. (1999) Revision of the genus Selonodon Latreille (Coleoptera: Cebrionidae). Occasional Papers of the Florida State Collection of Arthropods 10: 1-49.