are cylindrical and sometimes they can be light brown to the apex.
Alatae, produced in the second and third generations, are grayish-green with a black head and thorax, dark antennae, legs and siphunculi
and a large quadrate dark green patch on the dorsal abdomen; they migrate to various Polygonum and Persicaria spp.
After measuring the wet mounts, each aphid was dissected to remove the head, legs, and siphunculi
Rostrum shape and antennae length have similarity with available literature and most important variable characters are siphunculi
color, polygonal reticulation on 8th abdominal tergite and rostrum length.
Mummies were black in color each with an emergence hole usually at dorsum above the siphunculi
(Plates V and VI; Suppl.
Wahlgreniella nervata (Gillette 1908) is a spindle-shaped, pale green aphid characterized by elongate swollen siphunculi
, apterae without sensoria on third antennal segment, cauda bearing five hairs and well developed lateral frontal tubercles (Heie 1986).
The developing wasp cut with its mandibles a circular exit hole in the mummy, usually between the siphunculi
The comparative morphological study was conducted on species (i) whose apterae possess swollen siphunculi
and have been recorded in North America or (ii) are known to feed on Asteroideae species over the World.
Mummies are with emergence hole usually at dorsum between or above the siphunculi
Body is small and brown with dark siphunculi
and the cauda unusually long and pale.
Distinguishing characters of the Lachninae include: (1) anal plate whole, (2) cauda broadly rounded or arc-shaped, (3) processus terminalis of antennal segment VI noticeably shorter than base of this segment, (4) ultimate rostral segment with 2 clearly differentiated portions, (5) head bearing an epicranial suture is well separated from prothorax, (6) empodial setae short and fine, (7) secondary sensoria subcircular or slightly ovoid, (8) antennae usually shorter than body (slightly longer than the body in some species), and (9) siphunculi
troncoconic, short and robust (more or less volcano-like) with associated setae, or small at distal ring (poriform).
The classical separation of the subgenera Uroleucon, Uromelan and Lambersius is based on the pigmentation of the siphunculi
and cauda (considered separately and compared), and secondly on the color of the body when alive and the dorsal sclerites of the abdomen; also, Lambersius is restricted to America, except for certain anthropic introductions.