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Wax-banded daisy aphidOn this page: Identification & Distribution Biology & Ecology Other aphids on the same host
Identification & Distribution
Adult apterae of Aulacorthum palustre are whitish green, pale green or pinkish yellow with black tips to the antennae and legs. The dorsum and antennae have short capitate hairs. They often have rust-coloured or darker green spots around the bases of the siphunculi. The siphunculi are straight and pale, 1.8-2.5 times the length of the cauda, often with conspicuous darkened flanges. Immature Aulacorthum palustre are easy to recognise as they have serial cross bands of whitish wax powder around the body (see pictures below of fourth instar nymphs), but these are apparently lost by the adult stage.
The alate Aulacorthum palustre is reddish or greenish with a brown or black abdominal dorsal pattern. The siphunculi are brown or with brown apices.
Aulacorthum palustre feed on the underside of leaves of plants in the daisy family (Asteraceae) such as cats ear (Hypochaeris), oxtongues (Picris), and possibly dandelions (Taraxacum) and hawkbits (Leontodon). They do not host alternate but live all year round on the same host. They may produce sexuales in autumn and overwinter as eggs, or they may overwinter parthenogenetically as viviparae. Aulacorthum palustre is found throughout Britain and much of Europe.
Biology & Ecology
Aulacorthum palustre seems to be rather a rare aphid in Britain, and we have only found it on a few occasions. It is relatively easy to recognise in the field mainly on account of the serial cross bands of white powder on the bodies of the immatures as shown in the three pictures below.
Heie (2009) uses Aulacorthum palustre as an example of an aphid that, in Denmark at any rate, is rare having only been found once, despite its food plant being common. Heie observed that of 481 known species in Denmark, 93 had only ever been found once in that country (about 20%).
We suggest in Rare aphids and conservation that around half the aphids recorded in Britain can be regarded as rare. In the case of Aulacorthum palustre its apparent rarity may just result from it being under-recorded, given its cryptic habitat underneath lower leaves.
Other aphids on same host: