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Iziphya [Macrosiphini]Iziphya are medium sized aphids with oval or pear-shaped rather broad bodies. The aptera usually has a dorsal abdominal pattern of pigmented blackish areas. Alatae have a more-or-less regular series of dark bands on tergites III to VIII, those on III-VI often enlarged and fused into a central shield. The forewings have dark-bordered veins and dark areas along the distal parts of the veins. Apterae lack secondary rhinaria, and the rostrum is short. The fore and middle legs are modified for leaping, with enlarged femora and thick bases of tibiae. The base of the tibia has a heavily sclerotized 'knee-cap' which articulates with the femur. Empodial hairs are spatulate. Dorsal hairs are usually short and fan-shaped; there are no mushroom-shaped hairs, nor are there fan-shaped hairs on the lateral margins of the eye (between the eye and antennal socket). The dorsum is without membranous borders from the mesonotum to abdominal tergite I, and from tergites III or IV to VI. Siphunculi are stump-shaped with a rounded apical rim, apparently between segments V & VI. Note there is considerable variation in important diagnostic characteristics related to environmental factors, such as body pigmentation, antennal length and shape of dorsal hairs. There are 12 species of Iziphya worldwide, six are Nearctic, five are Palaearctic and one (Iziphya spenceri) is Holarctic. They feed on sedges, with no host alternation. All species are monoecious holocyclic. Iziphya are not attended by ants. Iziphya bufo (Jumping toad aphid) Europe, South-west & Central Asia.Adult apterae of Iziphya bufo (see first picture below) are yellowish or greenish yellow, usually with a pair of large dark areas on the metathorax, and dark areas around the siphunculi. The latter are more-or-less joined by a dark arc of pigment so there is never a clear spinal stripe - sometimes the dorsum is almost completely black. The head is dark, usually with a paler central area. Their antennae, which are about 0.7-0.8 times the body length, have segments I-II and IV-VI dark, and segment III pale with a dark apex. The terminal process is about 1.5 times the base of antennal segment VI. The dorsum and margins of tergites VI-VIII have both short fan-shape hairs and longer capitate or rod-shaped hairs (cf. Iziphya ingegardae, which have all dorsal and marginal hairs slightly capitate or pointed). There are no rod-shaped marginal hairs anterior to the siphunculi (cf. Iziphya memorialis, which has a few rod-shaped marginal hairs anterior to the siphunculi). Spinal hairs are borne on tubercular bases. The siphunculi are dark, stump shaped with a rounded apical rim. The body length of adult Iziphya bufo apterae is 1.4-2.1 mm. Immature Iziphya bufo are pale yellow with dusky siphunculi and rows of dusky spinal and marginal tubercles.
Pictures above copyright Pierre Gros under a cc by-nc licence. Alatae (see second picture above) have a dark central dorsal abdominal patch and broadly banded wing veins. Antennal segment III bears about 18-20 secondary rhinaria along the entire segment. The middle abdominal tergites each have two irregular transverse rows of hairs. Iziphya bufo lives on on various sedge (Carex) spp., especially Carex arenaria. Other recorded hosts include Cyperus rotundus, Juncus and grasses such as Cynodon dactylon. It is often found in drier situations such as sandhills, drained forest soil and steppe regions, but also sometimes in bogs. The species got the name 'bufo' (meaning toad) because of its ability to jump a short distance using its enlarged femora and tibiae - albeit other Iziphya share these traits. Oviparae and apterous males occur in September-October. Iziphya bufo is widespread in Europe, and in south-west and central Asia.
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