AGROMYZID LEAF MINERS — FRICK 431 



Phytomyza marginalis Frost 



Phytomyza. marginalis Frost, Ann. Ent. Soc. Amer., vol. 20, p. 219, 1927. 



The holotype female is in the U. S. National Museum (No. 50030). 

 This species and Phytomyza melanella are similar in having dark 

 frons, antenna, and tarsi, two equal-sized upper-orbitals, and the 

 acrostichals in two rows. From P. melanella this species can be 

 distinguished by having the third antennal segment subquadrate, the 

 genovertical plates moderately extending beyond the eye margin (fig. 

 159), and the first and second dorsocentrals equidistant from the 

 transverse suture. Known from two specimens from New York. 



Phytomyza melanella Frost 



Phytomyza melanella Frost, Mera. Cornell Univ. Agr. Exp. Sta., vol. 78, p. 86, 

 1924 (figure of wing). 



The holotype male is in the U. S. National Museum (No. 50026). 

 This species and Phytomyza marginalis are quite similar in having the 

 frons, antenna, and tarsi dark, both upper-orbitals of equal length, 

 and two rows of acrostichals. P. melanella has the thu*d antennal 

 segment rounded and the genovertical plates hardly extending beyond 

 the eye margin (fig. 160). Also, the first dorsocentral is about twice 

 as far from the transverse sutm'e as the second. I hereby restrict this 

 species to California. The specimen labeled as a paratype from 

 Kentucky is in very poor condition and is of another species. 



Phytomyza minuscula Goureau 



Phytomyza minuscula Goureau, Ann. Soc. Ent. France, ser. 2, vol. 9, p. 154, 

 1851. — Frost, Ann. Ent. Soc. Amer., vol. 23, p. 457, 1930 (figures of puparium 

 and leaf mines).— Hendel, in Lindner, Die Fliegen dcr palaearktischen 

 Region, fam. 59, p. 433, 1935 (figures of head and wing). 



Phytomyza nitida Melander, Journ. New York Ent. Soc, vol. 21, p. 271, 1913. 



Phytomyza aquilegia (Hardy), Coquillett (part), U. S. Dep. Agr., Div. Ent. 

 Bull. 10, p. 78, 1898 (specimens from Aquilegia sp.) — Melander (part), 

 Journ. New York Ent. Soc, vol. 21, p. 271, 1913 (2 cf &, Ithaca, N. Y., and 

 New Haven, Conn.). — Cory, Journ. Econ. Ent., vol. 9, p. 419, 1916 (figures 

 of leaf mines). — Frost (part), Mem. Cornell Univ. Agr. Exp. Sta., vol. 78, 

 p. 67, 1924 (figure of leaf mines). 



Phytomyza minuscula is a small dark Holarctic species (1.5 to 2 

 mm. in wing length) that has the frons dark. The dorsal upper- 

 orbital is minute and the ventral lower-orbital is about one-half the 

 size of the dorsal (fig. 161). This species is characterized by there not 

 being more than one setula in the intraalar row posterior to the trans- 

 verse suture and the inner postalar usually absent. The fourth 

 costal section varies from 2 to 3.4 times as long as the fourth costal. 

 The head has the eye relatively small and the antenna large (fig. 161). 



