SUBGENUS TRICHAPION — KISSINGER 369 



Material examined : Lectotype and 50 specimens. 

 Known distribution: 



United States: Arizona: No exact locality (USNM). Colorado: No exact 

 locality (USNM); Lincoln Co., Aug. 12, 1926 (UC). Illinois: New Canton, 

 Aug. 12, 1948, Sanderson and Stannard (INHS). Kansas: Douglas Co. (UK) ; 

 Hodgeman Co., July 17-25, 1917 (UK) ; Onaga July 7, 1925, R. H. Beamer (UK); 

 Sedgwick Co., 1,291 ft., 1916, R. H. Beamer (UK); Sumner Co., 1,189 ft., 1916, 

 R. H. Beamer (UK); Wallace Co., Aug. 11, 1926, W. Benedict (UK) ; Wichita, 

 Sept. 6, 1935, R. H. Beamer (UK). Nebraska: No exact locality (USNM). 

 Texas: Potter Co., July 7, 1927, R. H. Beamer (UK). 



Remarks: Although A. capitatum has hne priority over A. oblitum, 

 Fall (1898), as the first reviser, fixed the latter as the valid name. 



Schwitzgebel and WUbur (1942) collected this species on ironweed, 

 Veronia interior Small. 



Apion nigrum Group 



The five species comprising this group are distinct in that the 

 middle of the pro thorax is distinctly wider than the base and the 

 sides are strongly rounded at the middle; males of these species 

 exhibit more or less well developed secondary sexual modifications 

 of the front legs. The five species do not overlap m range. A. nigrum 

 Herbst occurs in the eastern half of the United States; A. dolosum 

 Fall occurs in the mountains of New Mexico and Aiizona; A. cor datum 

 Smith occurs on the Pacific Coast from Washington to southern 

 California; A. heterogeneum Sharp occurs in the mountains of central 

 Mexico; and A. lativentre Beguin-Billecocq occurs in Brazil and 

 Argentina. 



Of the five species, A. dolosum and A. nigrum are the most alike. 

 The former differs in that the sides of the prothorax are not as strongly 

 rounded, the beak of both sexes is comparatively long; the front tarsi 

 of the male are not strongly dilated, and the front femora of the male 

 are incrassate. A. nigrum differs from the other four species by the 

 dilated, densely pubescent front tarsi of the male. The front tibiae 

 of the male of A. heterogeneum are dilated, curved, and have long, 

 yellowish ciliae on the inner surface. The front tibiae of the male of 

 A. cordatum are minutely mucronate. A. lativentre is distinct in 

 that the basal lateral region of the prothorax is prominent on either 

 side of the middle. 



Apion {Trichapion) cordatum Smith 



Figure 17,a-c 



Apion cordatum Smith, Trans. Amer. Ent. Soc, vol. 11, p. 54, 1884. — Fall, Trans. 

 Amer. Ent. Soc, vol. 25, p. 163, pi. 4, fig. 3, 1898. 



Description: Length, 2.00 to 2.75 mm. 



Moderately robust. Black; pubescence conspicuous, white, coarse, 



