370 PROCEEDmGS OF THE NATIONAL MUSEUM vol. io4 



Thoracic bristles brownish yellow and somewhat flattened; lower 

 mesopleural bristle slightly shorter and weaker than upper; posterior 

 notopleural bristle considerably shorter and weaker than anterior. 

 Dorsocentral pair inserted nearer supra-alar bristle than transverse 

 suture, approximately in distal two-fifths of distance between them. 

 Apical pair of scutellar bristles only slightly shorter than basal pair. 



Coxae and legs entirely testaceous yellow. 



Wings with the usual pattern of genus. Apical half of humeral 

 cross-vein (th) black; costa not blackened at tip of th and subcosta. 

 Basal band abbreviated and ending in a subtriangular, nearly opaque, 

 dark brown spot at apex of apical process. First costal section 1.04, 

 second 1.73; third 1.23, and fourth 0.82 mm. long. Basal section of 

 fourth longitudinal vein 1.48, penultimate (median) 0.41, and ultimate 

 1.88 mm. long, strongly curved. Inner cross-vein 0.43 mm. long and 

 nearly parallel to the 0.86-mm.-long outer cross-vein. Whole anal 

 cell 1.23 mm. long, 3.0 times as long as the apical process (0.41 mm. 

 long). 



Halteres ochraceous yellow, 



Preabdomen 2.4 mm. long and 2.6 mm. wide, yellowish brown, 

 except for the wide yellow hind margins of second to fifth tergites; 

 sixth tergite with narrow hind margin; preabdomen covered with very 

 short brownish black hairs. Third to sixth tergites each marked with 

 pair of lateral black spots, irregular in shape. Sixth tergite 0.41 mm. 

 long, slightly longer than the fifth (0.35 mm.). Intersclerotal mem- 

 brane pale yellow, sternites testaceous yellow. 



The dorsoventrally flattened ovipositor sheath entirely ochraceous 

 yellow, opaque, densely covered with fine yellow hairs; mder at base 

 (1.11 mm.) than long (0.80 mm.), apically 0.48 mm. wide and basally 

 0.22 mm. high in profile. 



Types: Holotype 9 (Coll. Blanchard), Argentina, Entre Rios, 

 Concordia, November 1947, Ismael Minatta. Named in honor of 

 the collector. 



Tomoplagia minuta Hering 



Figures 95,/; 97, /i; Plate 21, figitbe 10 

 Tomoplagia minuta Hering, 1938, p. 187. 



This species pertains to the obliqua-grou-p and it is the smallest of 

 all; it may be easily distinguished from its allies (monostigma and 

 cressoni) as indicated in the key, and from biseriata (Loew) by the 

 mostly hyaline coloration of the second basal cell of the wing. 



Male: Length 2.8 mm.; wing 3.1 mm. long and 1.3 mm. wide, 

 nearly 2.4 times as long as wide. 



Head pale ochraceous yellow, 0.52 mm. long, 0.96 mm. wide, and 

 0.68 mm. high; antennae and mouthparts testaceous yellow. Frons 



