ICHNEUMON-FLIES, PART 2: EPHIALTINAE 259 



Genotype: Polysphincta pallipes Holmgren. 



The generic name is derived from the Greek "sinis" (a plunderer) 

 plus "arachna" (a spider), referring to the host relationship. 



This genus contains two Holarctic species, the European Poly- 

 sphincta nigricornis Holmgren 1860, the Oriental Polysphincta ceylonica 

 Ashmead 1896, and two undescribed species from Japan and India. 

 Of these, S. anomala differs from the rest of the species in so many 

 ways that it might be placed in a separate genus. For the present, 

 however, it seems best to treat it as an aberrant species of Sinarachna. 



Key to the Nearctic species of Sinarachna 



1. Third tergite about 0.85 as long as wide; mesoscutum entirely black; flagellum 

 of male with about 22 segments, of female with about 24 segments. 



1. pallipes (Holmgren) 

 Third tergite about 0.55 as long as wide; mesoscutum dark brown, usually 

 its anterolateral margins and broad stripes along the notauli yellowish; flagel- 

 lum with about 14 segments in male, with about 16 segments in female. 



2. anomala (Holmgren) 



1. Sinarachna pallipes (Holmgren), new combination 



Figure 324,g 



Front wing 3.5 to 4.9 mm. long; body and legs rather slender; 

 flagellum of male with about 22 segments, of female with about 24 

 segments; third segment of hind tarsus about 3.0 as long as deep; 

 third tergite about 0.85 as long as wide. 



Black. Scape and pedicel of male whitish, brownish above; scape 

 and pedicel of female whitish to brown in front; flagellum of male 

 pale brown basally below; mouth parts, tegula, subtegular ridge, 

 hind corner of pronotum, and front and middle legs white or pale 

 stramineous; mesepimeron brown to stramineous; hind coxa ivory, 

 light fulvous basally; hind trochanters ivory; hind femur ivory, its 

 base and most of its front and hind faces except near base and apex, 

 light brown; hind tibia white with a narrow, faint, subbasal infuscate 

 ring and its apical 0.2 fuscous; hind tarsus fuscous, the basal 0.75 ± 

 of its first segment and sometimes also of its second and third segments 

 whitish to light brown. 



There are European and American subspecies, distinguished by 

 whether or not the thorax is partly fulvous. 



1. Mesothorax without fulvous markings, entirely black except for the white 

 subtegular ridge; scape and pedicel of female whitish in front; range: 



Europe la. pallipes pallipes (Holmgren) 



Mesothorax more or less fulvous, at least the upper hind part of meso- 

 pleurum fulvous ; scape and pedicel of female dark brown or partly light brown 

 in front; range: Nearctic America lb. pallipes strigis (Howard) 



