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Neonipponaphis aphidsOn this page: Neonipponaphis shiiae
Apterae of Neonipponaphis on their secondary host are aleyrodiform (=whitefly larva shaped), flattened dorsoventrally, without frontal horns, and strongly sclerotized. They comprise three parts: the prosoma (consisting of fused head, thorax, and abdominal segment I); abdominal segments II-VII fused together but distinctly separated from the prosoma (cf. Nipponaphis, which has these not distinctly separated from the prosoma); abdominal segment VIII, which is free. The strongly sclerotised prosoma bears pustulate ornamentation and numerous fine hairs (cf. Nipponaphis, which does not have numerous fine hairs on the prosoma). The eyes have 3 facets. The antennae are much reduced, indistinctly 3-segmented, (4 in immatures) with primary rhinaria placed wide apart on the terminal segment. The rostrum is short and thick, with the apical rostral segment blunt wedge-shaped, with 6 hairs. Abdominal tergites II-VII bear scattered shorter hairs. In addition each tergite has a pair of longer submarginal hairs, with the hairs on tergites V-VI shorter than hairs on other tergites, and with 4-8 hairs on tergite VIII. Tergites II and VII each have a pair of spinal setae. Hairs on the tibiae are long and fine, and the hind tibiae have several short peg-like hairs on the distal part; chaetotaxy (=bristle arrangement) on the first tarsal segment is 2-2-2 (fore-mid-hind). The siphunculi in the apterae are small and pore-like. The cauda is knobbed and constricted at the base, and the anal plate is bilobed.
The antennae of alatae (sexuparae) are 5-segmented (cf. Eriosoma, which have 6-segmented antennae, but similar wing venation). The eyes are compound. The wings are dusky and reticulated. The forewings have the pterostigma dark and broadly rounded at the hind margin, and the media is once branched; the hind wings have 2 obliques. The abdomen has 4 pairs of spiracles. Siphunculi are low, but much expanded basally, with distinct minute papillae around the pore. The cauda is short, broad, and semicircular.
Neonipponaphis is a genus of 2 species, very similar to Nipponaphis, their closest relatives. They are only known from their secondary host, chinquapins (Castanopsis), where their apterae live on branches, are ant-attended and largely wax-free. Like other Nipponaphidini, their primary hosts are probably winter-hazel (Distylium spp.), where they most likely produce galls. Neonipponaphis are found in Japan, and more recently China (Fujian).
Neonipponaphis shiiae (Japanese chinquapin aphid)
Adult apterae of Neonipponaphis shiiae on their secondary host are small, sessile and aleyrodiform (=whitefly larva shaped). They are blackish-brown to almost black, with a reddish tinge, and many long fine dorsal hairs (see first image below). There appear to be several small distinct areas of wax production in both immatures and adults, albeit there is little wax on the adult apterae (possibly due to ant-attendance). The body is circular, a little depressed, and flattened on the dorsum. The antennae are slender, nearly as long as the distance between them, but do not reach fore-coxae. Antennal segment III is fused with segment IV, and not well defined from segment II (but distinct in early instars). The eyes consist of triommatidia. The apical rostral segment is 1.8 times the second hind tarsal segment. The cephalic, thoracic, and first abdominal tergites are fused to form a prosoma (=cephalothorax), which has many fine hairs scattered on the dorsum, about 3 or 4 times as long as the middle diameter of antennal segment III. There are also many subcircular or oval pustules on the prosoma, those around the anterior thoracic spiracles being much smaller, conical, pointed and dark. (cf. Neonipponaphis pustulosis, where those around the anterior thoracic spiracles are oval or rounded). Posterior abdominal tergites II–VII are fused, forming an abdominal plate, but distinctly separated from the (much larger) prosoma by a pale membranous furrow (cf. Nipponaphis spp., where they are not distinctly separated, at least in the medial area). The abdominal plate has about 5 submarginal hairs in a row along each lateral margin, a pair of hairs near the hind margin, and about 17 scattered hairs. Siphunculi are small. The cauda is dusky, constricted basally and broadly rounded at the hind margin. The anal plate is dusky and bilobed. The body length of adult Neonipponaphis shiiae apterae is 1.3-1.7 mm.
Images above by permission copyright Aoki & Kurosu (2022).
Neonipponaphis shiiae on their secondary host produce alatae in May. Originally assumed to be secondary migrants, these are now believed to be sexuparae (Aoki & Kurosu, 2022) - viviparous alate secondary migrants are perforce unknown. The body and wings of sexuparae are dark metallic blue in life (see second picture above). In clarified slide mounts they are black, with dusky wings and a dark pterostigma. The head has 12-15 large hairs scattered on the posterior dorsum. The antennae are stout, shorter than half the body length. Secondary rhinaria are distributed 27 on antennal segment III, 13 on segment IV, and 5-6 on segment V. The apical rostral segment is about as long as the second hind tarsal segment, with very long apical primary hairs as in Nipponaphis. The wings are reticulated. On the forewing the pterostigma is broadly rounded at the hind margin, the anal vein (Cu1b) is much thicker than the cubitus, and the media is once branched. The hind wing has two obliques. The abdomen has many dorsal hairs. The siphunculi are small at the apex, but have a much-expanded base, with distinct minute papillae. Tergite VII has 2-4 rather large sclerites and 4 hairs, and tergite VIII is sclerotized on the dorsum and bears 10 long hairs. The cauda is very short, constricted basally, and has 4 or 5 long hairs on each side. The anal plate is divided, with 7 long hairs on each lobe. Body length of the Neonipponaphis shiiae sexupara is about 2 mm.
Neonipponaphis shiiae is thought to be a host-alternating aphid, albeit only known from its secondary hosts, chinquapin (Castanopsis spp.). Colonies occur on twigs, are usually ant attended, earth-tented and persist year-round. Sexuales (males and immature oviparae) are only known via culture of alate sexuparae. The Japanese chinquapin aphid has only been recorded from Japan and some of its islands.