﻿amerigAna 



VOL. VI. 



BROOKLYN, JUNE, 1890. 



No. 6. 



THE BLACK PEACH APHIS. 



A new species of the genus Aphis. 



By Erwin F. Smith, Sc. D., Washington. D. C. 



Aphis persicae-niger n. sp. 



Winged viviparous female ( pscudogyiia inigraus). — Antennae as long 

 as the body, sometimes a little longer or shorter, black or dark brown, borne 

 on widely separate, inconspicuous tubercles, joints imbricated, vi and vii con- 

 spicuously so, the seventh always a little longer than the third; iii, 0.49 — 0.56 

 mm.; iv, 0.33 — 0.40 mm.; v, 0.20 — 0.29 mm.; vi, c.09 — o.ii mm.; vii, 0.47 — 

 0.61 mm.; sensoria rather large (o.oi — 0.02 mm.) ringed and distinct, numer- 

 ous and very protuberant, giving to the under surface of the antennae a 

 strongly tuberculate, almost serrate character, about 40 on iii in three irreg- 

 ular rows, about 20 on iv in two rows, 5 or 6 on v in one row, and a group 

 (4 — 6) on the rather broad distal end of vi, one of them longer than the 

 others. Beak 0.69 — 0.96 mm., usually not much more than reaching to the 

 second pair of coxce. Thorax arched with a conspicuous button-like tubercle 

 between the wings, black shining. Legs parti-colored; tarsi and tips of tibiae 

 (distal one-fourth or one-fifth) black or dark brown, coxte and distal portion 

 of femora (two-thirds, more or less) also dark, the rest pale or yellowish; 

 femora smooth, or nearly so; tibiae rather evenly and strongly spined beneath; 

 tarsi 0.127 mm. Wings hyaline, slightly irridescent, no dusky patches or 

 bands, stigma pale, rather broad (0.15 mm.). Abdomen somewhat con- 

 stricted at junction with thorax, rounded behind and rather compact, seldom 

 much longer than broad, slightly margined; dorsum smootii, black and 

 shining throughout, or sometimes bordered with brown, never roughened, 

 tuberculate, mealy, or punctate; venter uniform black or dark coffee-l)rown, 

 no green or greenish markings. Cornicles twice the length of the tarsi and 

 nearly three times the length of the style (0.25 mm. in most individuals), 

 truncate and distinctly flanged, largest at the base (0.07 mm.) and tapering 

 gradually to the apex (0.04 mm. under the flange), sometimes narrower at the 

 base and slightly expanded in the middle, but never clavate, black or dark 

 brown, smooth or indistinctly imbricate, opaque or translucent. Style not 

 cone shaped, but very blunt rounded, nearly as long as broad (0.09 mm. X 

 o.ii mm.) and always a little shorter than the tarsi, provided with a few long 

 Entomologica Americana. Vol. VI. 6 Jvne, 1890. 



