354 PROCEEDINGS OF THE NATIONAL MUSEUM vol. in 



Subfamily Sehirinae 



Sehirides Amyot and Serville, 1843, p. 96. 



Diagnosis. — Either the arrangement of the two trichobothria of 

 sternites III-VII in a transverse row posterior to the spiracle (fig. 171) 

 or the venation of the metathoracic wing (fig. 166, shape of radial 

 cell and presence of a hamus) will define this group in the technical 

 sense. For greater ease of identification of the sole species of the 

 only genus that occurs in the Western Hemisphere, one may rely 

 on the narrow, creamy white lateral margins of the pronotum, corium, 

 and abdomen.^ 



Description.- — ^Head: Margins entire; antennae 5-segmented ; labial 



II simple. 



Wings: Posterior wing (fig. 166) with r-m joining M distad of 

 fracture in Sc + R; Sc and R leaving radial cell at antero-apical 

 angle; radial cell receiving hamus from M. 



Scutellum: Long, surpassing apices of clavi, latter not forming 

 commissure posterior to scutellar apex. 



Thoracic pleurae: Posterior margins well developed; propleuron 

 with anterior and posterior convexities; mesopleuron with posterior 

 margin touching or overlapping anterior edge of metapleuron for 

 most or all of width; metapleuron with posterior margin reaching 

 base of abdomen across full width, completely covering internal 

 part of hind coxa. 



Legs: Anterior tibia weakly compressed, with row of small blunt 

 spines on dorsal margin; tarsi inserted at apices of tibiae, with II 

 more slender than I or III. 



Sternites (fig. 171): Sutures nearly straight, not sinuate laterally; 



III to VII each with two trichobothria in transverse row behind 

 spiracle. 



Terminalia: Male genital capsule opening dorsall}^ 



Type of subfamily. — Genus Sehirus Amyot and Serville (1843, 

 p. 96). 



Distribution. — Members of the Sehirinae have been reported 

 from all major fauna! regions of the world except the Australian and 

 Neotropical. The range of the single New World species extends 

 southward from southern Canada into Mexico. 



Discussion.— This subfamily, as defined here and in the key to 

 subfamilies, is now known to contain the two genera Legnotus Schiodte 

 (=Gnathoconus Fieber, vide China, 1943) and Sehirus Amyot and 

 Serville. Only Sehirus has been found in the Western Hemisphere. 

 A more detailed discussion of this genus is given below. 



> One other species in the New World has >a creamy white costa, but it lacks the pale edges on the pronotum 

 and abdomen. 



