| Platydracus cinnamopterus complex |
Go to species key Diagnosis: Small (12-19 mm), slender, parallel-sided Platydracus; body and appendages generally light to dark reddish brown, uniformly colored or not on head and pronotum to always variegated on abdomen, with darker venter (except abdominal apex, more or less reddish) and black scutellum; pubescence light to dark, on abdomen forming more or less distinct, paired black pubescent lines near middle and diffuse lighter pubescence laterally; head and pronotum with dense umbilicate punctures except for a complete mid-longitudinal impunctate line on the pronotum at least one puncture diameter wide; antenna pubescent from 4th antennomere; mandibles stout, apically acute, each bearing three stout median teeth (two dorsal, one ventral on left, one dorsal and two ventral on right mandible, in both cases with only two teeth visible in dorsal view); mentum brown, sclerotized, anterior edge emarginate; pronotum about as wide as long; sutural length of elytra about 0.6 times as long as pronotum; protibia usually with two stout setae in row on external edge and one posteriorly; apex of 6th visible abdominal sternite in male with broadly rounded emargination, in female with broadly rounded, non-emarginate apex, sexual dimorphism otherwise absent externally and limited to venter of genital segment and genitalia; aedeagus not or very inconspicuously asymmetrical. A species known as Staphylinus or Platydracus cinnamopterus (Gravenhorst) meeting the above diagnosis was for nearly two centuries considered the most common and widespread Platydracus species in eastern North America. In the early stages of a revision of this genus for the New World, it became apparent to the second author (Newton 1973) that three species with quite different male genitalia were being confused under this name. After further study of type material of all relevant names, including several that were long considered synonyms of P. cinnamopterus, it was established that two of the species had available names and the third was undescribed. The three species are broadly sympatric in eastern North America and all occur within at least the southern part of ECAS. They are closely similar externally and difficult to distinguish (especially older or darker specimens in poor condition) without use of male genitalia (but see external characters in key). In order to clarify the status of the available names and allow recognition of these species, the new species (P. praetermissus Newton, spec. nov.) is formally described here and the other two species (P. cinnamopterus and P. zonatus, both Gravenhorst 1802) are redescribed and their identities fixed by review of type material, including designation of lectotypes where necessary. Platydracus cinnamopterus (Gravenhorst 1802)
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