Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
ref photo for peter Messer - Schizogenius litigiosus

ref photo for peter Messer - Schizogenius litigiosus
Portal , Cochise County, Arizona, USA
August 3, 2017
Size: 5.2 mm

Moved from Schizogenius.

Schizogenius litigiosus Fall [AZ rec. n.]
Schizogenius litigiosus Fall [AZ rec. n.] is my physical determination for this female specimen which is added to the PWM synoptic set of North American Caraboidea. Thank you Margarethe for this important specimen.

It fits well the key by Whitehead (1972) for S. litigiosus and matches the images of the holotype. I found the characters used in couplets 7 and 12 of Lindroth's 1961 key to be misleading and which would likely lead to failed recognition of some species. S. litigiosus is the western counterpart of very similar eastern S. sulcifrons Putzeys of which I have a good specimen to compare. As Whitehead observed, both species are dark piceous dorsally but only S. litigiosus has abdomen darkly concolorous while S. sulcifrons has abdomen distinctly paler.

Known in nearby southern California and Nevada, S. litigiosus newly extends to Arizona with this specimen. It is recorded at the Registry of Nearctic Geadephaga.

Moved from Ground Beetles.