120 NINETEENTH REPORT STATE ENTOMOLOGIST OF MIN NESOTA—I9Q22 
as a point in the margin of the wing; media slender but usually more 
distinct than in the Lachnini; colors of the body brown or black and 
wings often with smoky bands or spots. Found on woody parts of 
trees and other woody plants. The tribe is represented by the fol- 
lowing genera in Minnesota: 
a. Stigma elongate, extending far in the stigmel celi and truncate at the 
distal end!; no abdominal dorsal tubercle present. ...2% 42.67. oo oeuer 
Genus LONGISTIGMA 15 
b. Stigma elongate, pointed distally ; radial sector long end curved only basal- 
ly; abdomen with a median dorsal tubercle or gland.................. 
Genus TUBEROLACHNUS 16 
c. Stigma short: radial sector strongly curved; wings usually with dusky 
DALCHES hs, cans | aysierd BERR ee beso PA ro PAIN Genus PTEROCHLORUS 17 
15. Genus LONGISTIGMA Wilson, 1909. Type: Aphis caryae 
Harris, 1841. Stigmal vein arising some distance back of the apex 
of the very long and narrow stigma and only slightly curved near 
its base, running almost as a straight vein; stigma truncate at apex 
in the middle of the stigmal cell, and continued as a dusky band to 
or beyond tip of stigmal vein; found on woody parts, as trunks and 
limbs, of oak, hickory, basswood, etc. One species is known from 
Minnesota : 
(9) LONGISTIGMA CARYAE (Harris) Wilson, 1909 
This very characteristic species is rather abundant in Minnesota. 
The primary habitat is oak rather than hickory. It has repeatedly 
been taken on Tilia, hickory and other trees, but the sexes are 
known only from the oak. The species was well described by 
Monell under the name Lachnus longistigma taken on Tilia. 
16. Genus TUBEROLACHNUS Mordwilko, 1908. Type: Aphis 
viminalis Boyer, 1841. Stigma long, apically rounded and ending 
in the margin of the wing. Abdomen with a dorsal median tubercle, 
which is apparently glandular in function. Found in large colonies 
on woody parts of willow. One species is known from Minnesota : 
(10) TUBEROLACHNUS VIMINALIS (Boyer) Mordwilko, 1908 
Found on various willows, Salix. 
17. Genus PIEROCHLORUS Rondani, 1848. Type: dphis ro- 
boris Linnaeus, 1758. Stigma short, apically rounded; stigmal vein 
strongly curved; wings usually with spots. Found on woody parts 
of oak and rose. One species is known from Minnesota: 
~ (11) PTEROCHLORUS ROSAE (Cholodkovsky) 
Found on the stalks of the rose, usually close to the ground or 
even partly under ground. 
