Hesperoboreus brevicaudus  (Byers, 1961)


Diagnosis:  This is one of two species of Hesperoboreus that can be separated from Boreus by the relatively short maxilla-labial complex of the rostrum; lack of spines on the male forewing (except apical spine); male ninth tergum lacking medial hood; male ninth sternite smoothly rounded; forewing of female with apical bristles; female ovipositor short, ninth sternite less than twice height of eighth segment. 


Distribution – Geographical:  this species is known from the lower elevations (30 to 579 m) of the Coast Range and Willamette River Valley of Oregon north to the lower elevations of the Olympic Mountains of Washington (Penny, 1977).


Distribution – Temporal:  Adults have been collected from 16 October until 31 December.


Ecology:  On Mary’s Peak near Corvallis, OR, this species can be found on vine maple, Acer circinatum Pursh), among the abundant epiphytic bryophytes covering the stems.  These bryophytes include Rhytidiadelphus loreus (Hedw.) Warnst. (Rhytidiaceae), Metaneckera menziesii (Hook.) Steere, and Neckera douglasii  Hook. (Neckeraceae) (Russell, 1979).


Biology:  At Mary’s Peak this species appears to breed in epiphytic rather than terrestrial bryophytes (Russell, 1979).


Notes:  The name comes from the Greek hesperus = western and boreus = boreal, and refers to the geographical position in the northwestern part of the Nearctic Region, as well as brevis = short and caudus = apical portion.




Byers, G.W. 1961. An unusual new species of Boreus (Mecoptera: Boreidae) from Oregon. Journal of the Kansas Entomological Society, 34:73-78.


Penny, N.D. 1977. A systematic study of the Family Boreidae (Mecoptera). University of Kansas Science Bulletin, 51(5)141-217.


Russell, L.K. 1979. A new genus and a new species of Boreidae from Oregon (Mecoptera). Proceedings of the Entomological Society of Washington,81(1):22-31.



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