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Pine needle aphidsOn this page: Eulachnus Eulachnus agilis Eulachnus brevipilosus Eulachnus rileyi
Identification Small, narrow and elongate greenish to olive brown aphids with long limbs. The siphunculi are slightly elevated, rim-like structures, barely visible in this image of an adult apterous Eulachnus. Antennae are 6-jointed.
This genus comprises about 17 species all of which live on the needles of Pinus. They are cryptic when feeding, but very active when disturbed. The best-known species show preferences for certain Pinus spp., but none is strictly confined to one species.
Eulachnus agilis (Spotted green pine needle aphid)Apterae are spindle-shaped, bright green with numerous dark spots and no wax. They are small with a body length of only 1.6-2.3 mm. The hind legs often have mottled pigmentation.
Found usually feeding on old needles on many Pines (Pinus spp.), but especially common on Scots pine (P. sylvestris). Occurs throughout Europe, and parts of Asia and introduced to North America. Does not host alternate.
Eulachnus brevipilosus (Light green pine needle aphid)Apterae of Eulachnus brevipilosus are spindle-shaped and slender with a body length of 1.4-2.2 mm. They are light green with numerous faint spots and no wax. The antennae are about 0.4-0.5 times body length - markedly longer than in the superficially similar Essigella. The legs are rather pale.
This first image shows an adult light green pine needle aphid on a pine needle. The second image shows a micrograph of Eulachnus brevipilosus in alcohol.
The light green pine needle aphid may be found feeding on needles on pines , especially on Scots pine (Pinus sylvestris) and stone pine (Pinus mugo). It does not host alternate. It is unclear whether sexual morphs are produced or they overwinter as viviparae. It occurs throughout Europe and parts of Asia, and has been introduced to North America and New Zealand.
Eulachnus rileyi (Active grey pine needle aphid)Wingless female viviparae are very elongate spindle-shaped, and vary in colour from dark olive green to orange-brown or grey. They have prominent blackish setae on the dorsum. Older specimens become covered in bluish-grey wax sometimes with tufts of wax filaments posteriorly. The hind pair of legs and other pairs to a variable extent are dark brown to black. The siphuncular cones are reduced to small blackish rings. The body length of apterae is 2.3-3.0 mm. Winged viviparae are similar to apterae, but with the head and thorax darker, and less prominent setae on the abdomen.
The active grey pine needle aphid can be found feeding on the needles of many species of pines (Pinus spp.). In Europe it occurs more commonly on European black pine (Pinus nigra) and mountain pine (Pinus mugo) than on Scots pine (Pinus sylvestris) They are cryptic when feeding, but become very active when disturbed. The species is found in Europe, the Mediterranean area and south west Asia and has been introduced into Africa south of the equator and America.