14 SOUTH AMERICAN TIPULIDAE 



Two males from Lima, Peru, altitude 500 feet, August 19, 20, 

 1914, collected by Parish. 



Genus ORIMARGA Osten Sacken 

 Orimarga andina s]). n. 



Light gray, the thoracic pleura with a broad silvery stripe; wings sub hyaline; 

 legs medium brown. 



Male. — Length, 8.6 mm.; wing, 5.8 mm. 



Female. — Length, 8.5 mm. ; wing, 6 mm. 



Rostrum and palpi dark brownish black. Antennae very dark brown, the 

 first segment dusted with gray. Head light gray, brightest on the front. 



Thoracic praescutuni plumbeous with a gray l^loom; an indistinct darker 

 median stripe; lateral margin of the sclerite brightest; scutum light gray, each 

 lobe with a darker mark, these marldngs almost contiguous on the middle line, 

 scutellum pale brown; postnotum with a pale gray bloom. Pleura light silvery 

 gray with an indistinct narrow brown line from the cervical sclerites to the 

 base of the halteres; sternites darker, brownish, the sternum and the pleura 

 together enclosing a broad silvery stripe. Halteres with the extreme base 

 orange brown, stem white, knob brown. Legs with the coxae and trochanters 

 orange-brown with a very sparse gray bloom; remainder of the legs brown. 

 Wings with the extreme base orange-brown; remainder subhyaline; veins 

 brown. Venation: (see plate I, fig. 7) basal deflection of Cih about mid-length 

 of the radial sector. 



Abdomen dark brown with a sparse gray bloom, the hypopygium reddish. 



Habitat. — Colombia. Holotype, cf, La Cumbre, Colombia, 

 altitude 6600 feet. May 15, 1914 (Parish coll.). Allotype, 9, 

 topotypic. 



The described American species of this genus may be separated 

 by the following key: 



1. Wings subhyaline with dots on the cross- veins and deflections of veins 



[color of the body blue-gray; legs pale, almost white]. (British Guiana) 



punctipennis Alexander ^^ 

 Wings subhyaline or suffused with darker, not spotted with brown .... 2 



2. Tips of the tarsi white. (Panama) niveitarsis Alexander's 

 Tips of the tarsi not white. 



3. Thoracic pleura without a silvery band; legs pale yellow with the tip of 



the femur, base and tip of the tibia black. (Southwestern United 



States) arizonensis CoquiUett '' 



Thoracic pleura with a broad silvery band ; legs with the segments imif orm 



in color throiighout 4 



1^ 1914. punctipennis Alexander, Trans. Am. Ent. Soc, xl, p. 239, pi. IV, 

 fig. 3. 



" 1915. niveitarsis Alexander, Proc. U. S. Nat. Mus., xlix, p. 765, pi. 75, 

 fig. 5. 



i» 1902. arizonensis CoquiUett, Proc. U. S. Nat. Mus., xxv, pp. 83, 84. 



