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Hormaphidinae : Cerataphidini : Astegopteryx formosana
 

 

Astegopteryx formosana

Dark-spot horned aphid

On this page: Identification & Distribution Other aphids on the same host

Identification & Distribution

Adult apterae of Astegopteryx formosana are very broad-bodied and pale yellow or greenish-yellow, with the head, pronotum and siphunculi brownish-orange. There is an extensive unbroken, dark blue-green patch on the dorsum which is broadest anteriorly (cf. most other Astegopteryx are with or without green, but the green is always interrupted, at least absent in the middle of abdominal segment III and IV). There is a marginal fringe of white wax on the head, and all thoracic and abdominal segments. The head bears frontal 'horns' with rounded tips. The antennae are pale and have 4, or (incompletely divided) 5 segments. The apical rostral segment (RIV+V) is 0.59-0.77 times as long as the second hind tarsal segment. The head is fused to the pronotum. The abdominal segments have almost colourless marginal and marginal sclerite wax glands. Abdominal tergite VI usually has 3 or more hairs, and tergites II-III each have 9-15 hairs in addition to those near the wax glands (cf. most other Astegopteryx, where tergite VI usually has 2 hairs, and tergites II and III each have 4-11 hairs). The legs are pale. The siphunculi are cone shaped. The cauda is transversely elongate, somewhat constricted at the base and with 7-9 hairs.

Note: Blackman in Aphids on Worlds Plants points out that slide-mounted specimens of Astegopteryx formosana are difficult to distinguish from Astegopteryx bambusae, but in life the broad abdomen and dark blue-green patch (see above) are distinctive. This dark patch is not sclerotized, so does not show in a clarified mount.

Images above by permission, copyright Sunil Joshi & Poorani, J. Aphids of Karnataka. (accessed 12/8/20).

The alate Astegopteryx formosana has a brown head and thorax, with a yellowish green or yellow abdomen largely covered with a dark greenish-black dorsal spot. Their eyes and antennae are black, and the legs are colourless apart from the tarsi, and distal ends of the femora and tibiae. The head has very short frontal horns.

Images above by permission, copyright Sunil Joshi & Poorani, J. Aphids of Karnataka. (accessed 12/8/20).

Astegopteryx formosana is found on the undersides of bamboo leaves (Bambusa, Dendrocalamus, Gigantochloa). In Taiwan this species seems to be mainly restricted to Dendrocalamus latiflorus, although it has also been found on Bambusa oldhami. Astegopteryx formosana occurs from India across to China and Taiwan and south to Indonesia and Malaysia.

 

Other aphids on the same host

Astegopteryx formosana has been reported on 3 genera of bamboos (Bambusa, Dendrocalamus, Gigantochloa) as well as on several unspecified genera.

Acknowledgements

We are grateful to Sunil Joshi & J. Poorani for permitting us to use their excellent images from Aphids of Karnataka. We have used the keys and species accounts of Noordam (1991) together with those of Roger Blackman & Victor Eastop in Aphids on Worlds Plants. We fully acknowledge these authors and those listed in the reference sections as the source for the (summarized) taxonomic information we have presented. Any errors in identification or information are ours alone, and we would be very grateful for any corrections. For assistance on the terms used for aphid morphology we suggest the figure provided by Blackman & Eastop (2006).

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References

  • Noordam, D. (1991). Hormaphidinae from Java (Homoptera: Aphididae). Zool. Verh. Leiden 270, 1-525. Full text