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Ericaphis are rather small pale green or brown, often shiny aphids. The antennal and median tubercles on the head are variously developed and the antennae are shorter than the body. Apterae have no secondary rhinaria on their antennae, whilst those of alatae have a few on segment III only. Dorsal body hairs are short and blunt. The dorsal cuticle of apterae is wrinkled or corrugated. The apterae lack dark dorsal markings, but alatae have a dark dorsal abdominal patch. Their siphunculi are of moderate length, cyclindrical or tapering, and often slightly curved outwards at the end. The cauda is finger or tongue-shaped.
Ericaphis feed on heaths (Ericaceae), Rosaceae and Liliaceae. There are nine species in the world of which 3 are native to Europe, and 6 to the Americas. Some of the American species have been introduced to Europe.
Ericaphis ericae (Cross-leaved heath aphid) Europe
Adult apterae of Ericaphis ericae are green or brownish green with the tips of the antennae and legs black. The hairs on the third antennal segment are conspicuous, the longest of these hairs being 0.6-0.9 times the basal diameter of that segment. The fused last two segments of the rostrum (RIV+V) are 1.3 to 1.5 times longer than the second hind tarsal segment (HTII) (cf. Ericaphis latifrons which has RIV+V 0.9-1.2 times longer than HTII). The first tarsal segments usually have three hairs. Ericaphis ericae siphunculi have a large flange at the end. It is a small species with a body length of 1.1-1.7 mm.
Cross-leaved heath aphids live without host alternation on Erica species, especially cross-leaved heath (Erica tetralix), feeding on flowers and shoot apices. Oviparae and apterous males are produced in September and October. Blackman (2010)) notes that Ericaphis ericae is often overlooked because of its small size and cryptic colouration. It is found in Britain and continental Europe, east to Poland and south to Spain and Portugal.
Ericaphis scammelli (Blueberry aphid) North America, Europe
Adult apterae of Ericaphis scammelli are usually pale yellow-green (see first picture below), but we have also found a pink form (see colour forms below). The median frontal tubercle is prominent and the antennal tubercles tend to be rather low, so that the front of the head has a W-shaped outline in dorsal view (see micrographs below). The siphunculi are long and straight, 1.4-2.0 times as long as the finger-shaped cauda, with the aperture not turned outwards, and a moderate flange (see pictures below of live and preserved Ericaphis scammelli). The body length of adult apterae is 1.5-2.4 mm.
Third image above copyright Andrew Barclay, all rights reserved.
Alate Ericaphis scammelli are usually green (see second picture above), or occasionally pink, with dark brown dorsal abdominal markings fused into a central patch, and a pale window between the siphunculi.
Ericaphis scammelli feed on blueberry (Vaccinium), aggregating on the stem of the growing point, and along the veins on the undersides of the leaves. The species is native to North America, but has been introduced to England, Sweden, Netherlands and Italy. In Britain it has been found on blueberry seedlings and imported plants since the 1970's, with several records in Kent in recent years. Our samples came from cultivated blueberries (Vaccinium corymbosum) in Peterborough, Cambridgeshire, and from Berry Gardens in Clock House Farm, Coxheath, Kent.