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Allaphis [Thripsaphidini]The apterous viviparous female has the antennal tubercles poorly developed, but the median frontal tubercle is often prominent. The antennae are six-segmented, sometimes with a few secondary rhinaria on segment III. The eyes are compound, but without an ocular tubercle. The rostrum is short, barely extending beyond the fore-coxae; the apical rostral segment is short & blunt. The femora are not greatly enlarged, and the first tarsal segments normally have 5 ventral hairs, none dorsally. The empodial hairs are setiform (= bristle-like) (cf. other genera in the Saltusaphidinae, which have flabellate (= fan-shaped) empodial hairs). Hairs on abdomen and thorax are mostly short and inconspicuous. Abdominal tergites III-VI are fused, with the limits of segments only discernible dorsally. There are no clusters of wax pores. The dorsum has conspicuous nodules. Abdominal tergite VIII is rounded, weakly bifid, or with a distinct median protrusion on the posterior margin (cf. Saltusaphis spp., which have the apex of tergite VIII incised) . The anal plate is bilobed, and the cauda is knobbed. The alate vivipara has circular or oval secondary rhinaria on segment III, and rarely also on segment IV. The dorsum of the abdomen has separate sclerotic transverse bars on each tergite, or some sclerites are fused to form a dark sclerotic patch. Marginal sclerites are mostly free, sometimes fused with spinopleural sclerites. The wings are elongate with normal venation. There are about 12 species of Allaphis aphids, feeding on various sedge (Carex) species. They are found in North America, Europe, and across Asia, and apparently have been introduced to New Zealand & Australia.
Note: In the past these species were treated as a subgenus (Trichocallis) of the genus Thripsaphis. Quednau (2010) restored the group of species to its full generic status under the name Allaphis. Allaphis foxtonensis (Aotearoa wax-fringed sedge aphid) New Zealand, possibly AustraliaAdult apterae of Allaphis foxtonensis are light green to light yellowish green, with mainly dusky antennae. There is extensive wax exudation laterally and ventrally, especially on the appendages and posterior. The body is elongated and somewhat flattened. Antennal tubercles are absent. The eyes are without ocular tubercles. The antennae are about 0.7 times the body length (cf. Allaphis producta, which has antennae less than 0.55 times the body length). Antennal segment antennal III bears 1-7 secondary rhinaria. The hairs on segment III are very short, only about 0.25 times the diameter of the segment, and the terminal process is about 0.8 times the base of antennal segment VI. The rostrum extends to the first pair of coxae. The abdominal dorsum has a scale-like pattern of imbrication, and bears a few small pointed hairs. The siphunculi are reduced to more-or-less round rimmed openings on each side of tergite VI. The cauda is knobbed, constricted at the middle, and with 11-14 hairs. The body length of adult Allaphis foxtonensis apterae is 2.4-2.7 mm.
Images above copyright Stephen Thorpe under a creative common licence. Alatae of Allaphis foxtonensis (not pictured here) have a dark head and prothorax, with a median pale yellow longitudinal streak down each of them. The abdomen is light green, with a black transverse band on each of tergites I-VII, but widest on tergites III-V. There are also black marginal sclerites on tergites I-VII, and tergite VIII is black. There is a light coating of white wax on the ventral surface. There are 12-17 variously-sized secondary rhinaria on antennal segment III. Allaphis foxtonensis is monoecious on Carex, especially Carex ternaria. Cottier (1953) found this aphid species very common on its host, especially at the bases of the young leaves in the centres of the plants. It has a habit of holding its antennae pointing straight ahead and flat on the leaf surface when at rest. When it moves, it does so rather rapidly, leaving a deposit of honeydew. The Aotearoa wax-fringed sedge aphid was first found in New Zealand, and then (possibly) in Australia (Eastop, 1966 notes that it may not be the same species as that found in New Zealand). Allaphis foxtonensis may be endemic to this region, but Blackman in Aphids on Worlds Plants felt that the lack of related species in the southern hemisphere means it is almost certainly an introduced species, so far undescribed in its home environment. That said, if it arrived some time ago, it may have changed somewhat. Allaphis producta (Wax-fringed sedge aphid) North America, Europe, AsiaAdult apterae of Allaphis producta (see two pictures below) are very elongate, rather variably coloured from yellowish white to pale greyish brown to blackish. They secrete bluish white wax, especially at the end of abdomen, with a little along the sides of the posterior tergites. The antennae are rather short (see note below), and are black apart from near the base. Antennal segment III has 1-5 secondary rhinaria on its distal half. Abdominal tergite VIII has its posterior margin bluntly triangular, and with a pair of hairs close together, one on each side of the apex (cf. Allaphis ossiannilssoni which have the two most medial hairs well separated). The siphunculi are reduced to small pores. The anal plate is bilobed, and the cauda is strongly knobbed. The body length of the adult Allaphis producta aptera is 1.8-2.5 mm.
Images above copyright Jochem Kuhnen, all rights reserved. Alatae of Allaphis producta have 10-14 rhinaria on antennal segment III, and broad black cross bars that are fused into a solid patch on abdominal tergites III-VI. Allaphis producta is monoecious holocyclic on leaves of sedges (Carex spp.). Oviparae and wingless males have been found in mid-July in Iceland, from August to September in Britain, and in mid-October in Spain. Allaphis producta is widely distributed in the northern hemisphere from North America, to Europe, and across Asia to east Siberia.
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