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BugGuide Gathering
Smoky Mountains
University of Tennessee Biological Field Station
August 8-10, 2008
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Photos from the last gathering (Minnesota 2007)

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Genus Elaphrus

Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Adephaga (Ground and Water Beetles)
Family Carabidae (Ground Beetles)
Subfamily Elaphrinae
Tribe Elaphrini
Genus Elaphrus
Other Common Names
Marsh Ground Beetles, Bog Ground Beetles
Pronunciation
eh-LAFF-rus
Numbers
Nearctica.com lists 19 species.
Size
circa 7-9 mm
Identification

Sexing specimens: "Adult males, except those of E. punctatus which lacks any secondary sexual characteristics, are recognized by enlarged basal tarsomeres of forelegs with white hair-like structures ventrally, termed spongy pubescence. In most species, males have a small tooth-like projection at the base of inner spur of the mid-tibia." More information in Goulet, 233.
Range
Much of North America, with a majority of species restricted to Alaska, Canada, and the northern United States.
Season
Spring to early summer. April-May (Minnesota). March-June (E. ruscarius, North Carolina).
Food
Predatory on other insects, presumably.
Remarks
Goulet postulates that the ancestor species arose in tropical Asia. Eventually species became extinct except for the immediate ancestor species of today's Elaphrini, which survived in Alaska and northern Siberia. From there the Elphrini radiated and evolved into current species. Today the Elaphrini are more common in Alaska, Canada, and the northern U.S. than in the southern states. (Goulet, 221.)

For those living in the eastern United States south of Pennsylvania, the most widespread species is Elaphrus ruscarius, which ranges widely all the way to the Gulf of Mexico. (Goulet, 371.)
Print References
Ciegler, pp. 32-33, fig. 44, lists E. ruscarius from South Carolina, with probably occurrence of E. californicus, which is found in North Carolina, Florida (3).
Salsbury, p. 165--photo E. ruscarius (4)
Arnett et al., pp. 75-77, fig. 199--E. ruscarius (5)
White, pp. 88-89 (6)
Sikes, pp. 50-51 lists 5 species from Rhode Island (7).
Brimley p. 116 (8)

(9) GOULET, H. 1983: The genera of Holarctic Elaphrini and species of Elaphrus Fabricius (Coleoptera:Carabidae): classification, phylogeny and zoogeography. Quaestiones Entomologicae, 19: 219-481
Internet References
North Carolina State Univ. Entomology lists two species from that state: cicatricosus (1 pinned), ruscarius (73 pinned)
Insects of Cedar Creek--E. ruscarius
Ground Beetles of Canada--Tribe Elaphrini, etc.