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Norway maple periphyllus aphidOn this page: Identification & Distribution Biology & Ecology Damage & Control
Identification & Distribution:Periphyllus lyropictus apterae (see first picture below) are yellowish with brown dorsal markings, usually comprising a broad spinal stripe on head and thorax and a large V-shaped mark on the dorsal abdomen. The terminal process of the sixth antennal segment is 4.5-6.0 times longer than the base of that segment. The antennal and dorsal hairs are acute and fine pointed. The siphunculi of the Periphyllus lyropictus aptera are pale to dusky, conical, and about as long as their basal widths. The cauda is tongue shaped, about as long as broad, and often with a slight constriction (cf. Periphyllus testudinaceus where the cauda is clearly shorter than its basal width). The body length is 1.9-3.0 mm.
Periphyllus lyropictus alatae (see second picture above) have dark marginal sclerites, but other dorsal sclerotization is limited to the spinal area, not forming cross-bands. The shorter hair on the basal part of the sixth antennal segment is 0.025-0.04 mm long (cf. Periphyllus hirticornis which has this hair 0.019-0.025 mm long). The siphunculi are 0.17-0.23 mm long (cf. Periphyllus hirticornis where the siphunculi are 0.21-0.28 mm long).
The Norway maple aphid lives on the undersides of leaves of Norway maple (Acer platanoides). They often form large colonies producing much honeydew and are visited by ants and other insects. Periphyllus lyropictus does not produce aestivating nymphs. Oviparae and alate males are produced in October-November. The Norway maple periphyllus is native to Europe, but it was introduced on Norway maple to North America, where it is now also widespread.
Biology & Ecology:
Periphyllus lyropictus eggs hatch early in spring and the fundatrices develop and stay on the bark of one-year old branches. Their nymphs constitute the second generation and develop on the undersides of the leaves, as soon as the buds open. There is then a third generation, some of which develop into alates. The alatae (see picture below) disperse to colonize other trees (Hill Ris Lambers, 1947 ).
Although most Periphyllus lyropictus colonies are on the undersides of leaves, they will occasionally establish a colony on the upperside of a leaf (see picture below).
Subsequent generations are usually apterous, and live in small groups on the undersides of the leaves along the main veins (see picture below).
The apterae often collect at the same spot and sit with their heads almost touching, depositing their offspring. Periphyllus lyropictus does not produce aestivating nymphs.
In the autumn a variety of different colour forms can be produced (see pictures below).
At this time they also produce oviparous females (see picture below) and alate males.
After mating, the oviparae lay their eggs on the wood of the branches.
A wide range of predators and parasitoids attack Periphyllus lyropictus - the picture below show the egg of a syrphid fly laid on the edge of the colony.
Another predator we have found active in Periphyllus lyropictus colonies is Anthocoris nemorum (see picture below), a well known predator of sycamore aphids (Dixon & Russel (1972) )
Hill Ris Lambers (1947) reports that the colonies of Norway maple aphids are usually attended by ants (Lasius spp.) during the summer. Stroyan (1977) notes that Periphyllus lyropictus may be locally common, but is little recorded.
Damage and control
Unlike most Periphyllus species, Periphyllus lyropictus causes marked leaf wrinkling at the site of the colony. Since it can be abundant, it is often considered a pest species both in America and in Europe (Ripka (1999)).