New Species of the Genus Nemotelus from the Western United States (Diptera: Stratiomyidae)
By Hanson, WJ
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contains a key to the species the subgenus Camptopelta found in America north of Mexico
Note: Although the key is labelled "Key to Species in America North of Mexico", it doesn't include
Nemotelus kansensis and it doesn't use the presence or absence of R4 as a character state.