Panorpa debilis  Westwood,1846


Diagnosis:  This is one of four species of Panorpa in the debilis group that are unified by the presence of unusually long, thin aedeagal hamuli as part of the male genitalia.  This group has forewings with entire apical and pterostigmal bands and no basal spots along the costal margin.  Males of Panorpa debilis have a series of stout bristles on a small lobe at the apex of the basistyles, and ventral parameres that are thin throughout, extend well beyond the basistyles, and apically cross.  Compared to the other species in this group, the aedeagal hamuli of P. debilis are shorter and divergent, not parallel.


Distribution – Geographical: This species is found in the cooler, more northern regions of the continent from New Hampshire south to Virginia and northward and westward through Ontario and Quebec to Wisconsin.


Distribution – Temporal:  June to September (Byers, 1954).


Ecology:  According to Byers (1954) this species lives in a variety of habitats that is most commonly characterized as damp swales with abundant, broad-leaved herbaceous understory.


Biology:  Nothing is known of the immature stages or life history of this species.


Notes:  Byers (1962) found Panorpa canadensis  Banks to be a synonym of this species based on a study of the type series (1♂, 1♀).  This appears to be a northern species with populations in the Appalachians.  There are currently considered to be four closely-related species in this species group (P. appalachia, P. bichai, P. debilis, and P setifera).  The other species in this group may be considered to be distinctive isolated populations of P. debilisPanorpa setifera is known from a single population at Parfrey’s Glenn in the deep ravines of the Wisconsin Dells at the western edge of the range of P. debilis.  It differs from other populations of P. debilis in the muchlonger setae on the ventral parameres, and the much longer aedeagal hamuli of the male genitalia (Webb, 1975).  Panorpa bichai also appears very similar to P. debilis and is found in a relatively small area of Tennessee near the southern end of the distribution of that species and in Indiana (Byers, 2002).  It varies from P. debilis in that the ventral parameres are more bowed outward at mid-length and extend further – half the length of the dististyles (Byers, 1993).  Finally, P. appalachia is known from two male specimensfrom Haywood  and Swain Counties, North Carolina.  It differs from P. debilis in that the ventral parameres are much broader apically and the tines of the aedeagal hamulus are longer and thinner (Byers, 2002).




Byers, G.W. 1954. Notes on North American Mecoptera. Annals of the Entomological Society of America, 47:484-510.


-----. 1962. Type specimens of Nearctic Mecoptera in European museums, including descriptions of new species. Annals of the Entomological Society of America, 55:466-476


-----. 1993. Autumnal Mecoptera of southeastern United States. University of Kansas Science Bulletin, 55(2):57-96.


-----.  2002.  A new Appalachian scorpionfly (Mecoptera: Panorpidae).  Journal of the Kansas Entomological Society 75(3):185-187.


Webb, D.W. 1975. New Species of Panorpa (Mecoptera: Panorpidae). Entomological News, 85:171-173.


Westwood, J.O.. 1846. A Monograph of the Genus Panorpa, with Descriptions of some Species belonging to other allied Genera. Transactions of the Royal Entomological Society of London, 4:184-196.



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