Other Common Names
Pedunculate Ground Beetle
Synonyms and other taxonomic changes
Orig. Comb: Scarites subterraneus Fabricius
Distinctive body form and huge jaws, elytra deeply striated.
As per Downie and Arnett, 1996, The Beetles of Northeastern North America, Volume 1, pp. 104-105, this species can be distinguished from the similar S. quadriceps by the shape of the antennal segments as noted below. The body length quoted by the authors for S. subterraneus is questionable in the opinion of Peter Messer. A better way to distinguish by size appears in the above key.
subterraneus: antennomeres 8-10 each as broad as long (moniliform).
quadriceps: antennomeres 8-10 each longer than broad (filiform).
Downie and Arnett also list a third species in the genus, S. lissopterus, but provide neither the ability to key it out nor a description. They list its distribution as: KS, NM, OK, TX, WI? [latter very unlikely according to Peter Messer].
CA-FL-NY-SD / Ont. (Bousquet & Larochelle 1993)
Under stones, leaf litter, etc., in soil
Historically much taxonomic confusion existed at the specific level.
Guide TBA--PC. (Dillon, other print refs, e.g., Ciegler life cycle.)
ID TBA--PC. (Given taxonomic confusion, consider moving everything, including guide? to genus level. Check Ciegler on this.)
05/07/06--I have added species info from Downie and Arnett. Does this clear some taxonomic confusion or are there still issues w/ this genus? --Ethan Friedman
See key to Scarites species
by Peter Messer that hopefully will resolve confusion.
Bousquet, Y. and A. Larochelle. 1993. Catalog of the Geadephaga (Coleoptera: Trachypachidae, Rhysodidae, Carabidae Including Cicindelini) of America North of Mexico. Memoirs of the Entomological Society of Canada, 167: 1-397.
live adult image (Bastiaan Drees, Texas A&M U.)
Insects of Cedar Creek
pinned adult image (John Haarstad et al, U. of Minnesota)
adult image and common name reference [Pedunculate Ground Beetle] (Don McIntire, Torrey Pines State Reserve, California)
Ground Beetles of Canada
preserved adult image (Henri Goulet, CBIF)
Systema Entomologiae (Fabricius), p.249
Original description of the species (in Latin)
pinned adult image of S. quadriceps
(Kirk Larsen, Luther College, Iowa) - right-click the photo and select "View Image" to see an enlarged version showing the elongated antennomeres 8-10