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Mint aphidOn this page: Identification & Distribution Biology & Ecology Other aphids on the same host
Identification & Distribution:
Ovatus mentharius apterae have been described as greenish-white (see first picture below), but pale green with darker green markings may be a better description of the adult aptera. The antennae are as long as, or longer than, the body. The inner sides of the antennal tubercle and the first antennal segment of Ovatus mentharius each have a forwardly directed process (see first micrograph below). The process on the antennal tubercle is as long as or longer than its basal width in dorsal view. The siphunculi are attenuated and cylindrical on the distal half, and at midlength are about as thick as the hind tibiae at midlength; the siphunculi are 2.0-2.5 times as long as the cauda. The body length of adult apterae of Ovatus mentharius is 1.2-1.8 mm.
The alate viviparous female has the head and thorax brownish, the abdomen green, the antennae black and the siphunculi brownish with paler bases. Immatures (see second picture above) are pale yellow-green.
The micrographs below are (first) a dorsal view of the head of Ovatus mentharius showing processes on antennal tubercle and antennal segment I, and (second) a ventral view of the adult aptera.
The clarified slide mounts below are of adult viviparous female Ovatus mentharius : wingless and winged.
The mint aphid does not host alternate and lives all year on the underside of leaves of mint (Mentha species). It is not attended by ants. Winged males and oviparae can be found in autumn. Ovatus mentharius is found over most of Europe south to Turkey and in central Asia.
Biology & Ecology
In southern England we have found flourishing colonies on water mint in March.
Hence it is likely that the species is overwintering parthenogenetically, at least in mild winters.
In much of Europe sexuales develop in autumn and the species overwinters in the egg stage. The ovipara is reported to be greenish yellow with small intersegmental sclerites on the dorsum. The siphunculi are thinner than in viviparae, the cauda is thicker, and the hind tibiae are swollen over almost their entire length. The male is alate with dark siphunculi and cauda.
Other aphids on same host:
Ovatus mentharius has been recorded from 8 Mentha species.
Blackman & Eastop list 26 species of aphid as feeding on Mint (Mentha species) worldwide, and provide formal identification keys (Show World list). Of those aphid species, Baker (2015) lists 17 as occurring in Britain (Show British list).