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Light green pine needle aphidOn this page: Identification & Distribution Biology & Ecology Other aphids on the same host Damage & Control
Identification & Distribution:Apterae of Eulachnus brevipilosus are spindle-shaped and slender. They are light green with numerous faint spots and no wax (cf. Eulachnus agilis which is bright green with numerous very dark spots). The antennae have six segments, and are about 0.4-0.5 times body length (cf. Essigella californica which has very short 5-segmented antennae). The name 'brevipilosus' indicates the aphid is short-haired. The third antennal segment is less than 0.24 mm. long and bears hairs less than 20 µm long (cf. Eulachnus agilis which has the third antennal segment more than 0.25 mm long and bears hairs 20-130 µm long). Also, the setae on the third antennal segment are no longer than the greatest diameter of that segment. The capitate hairs on the dorsal side of the hind tibia are no longer than the diameter of tibia at its midpoint (see micograph below). The legs are rather pale. The body length of an adult aptera is 1.4-2.2 mm.
The micrograph below shows the short capitate hairs on the hind tibia.
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. According to Blackman & Eastop (1994), sexual morphs have not been found - and they overwinter as viviparae. However, Zondag (1983) reports (perhaps wrongly) that sexual forms occur in Europe. Eulachnus brevipilosus occurs throughout Europe and parts of Asia, and has been introduced to North America and New Zealand.
Biology & Ecology:
Eulachnus brevipilosus are largely solitary and do not form colonies on the pine needles. One of the most notable features about this species is that the aphids are cryptophilic (= concealment-loving).
If they are disturbed, they run away and find a hiding place. The image above shows the typical hiding place between a needle pair and close to the needle sheath.
In New Zealand numbers peak in November and April. Several predators have been reported in New Zealand including the coccinellids Adalia bipunctata and Coccinella undecimpunctata, and the chrysopids Depanacra binocula and Micromus tasmaniae.
Other aphids on same host:
Blackman & Eastop list about 170 species of aphids as feeding on pines worldwide, and provides formal identification keys for aphids on Pinus.
Damage and control
Probing and feeding by this species causes chlorotic (yellowish) spots, and needles may fall prematurely. However, Eulachnus brevipilosus numbers are usually suppressed by the predators and fungal disease.