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Brachysiphoniella aphidsOn this page: Genus Brachysiphoniella Brachysiphoniella montana
Brachysiphoniella are rather small aphids with an oval, not elongated body. There are no prominent hairs. Antennal tubercles are absent. Eyes are normal. The antennae are much shorter than the body, and six-segmented. The terminal process is longer than the base of antennal segment VI. The wings have the media vein twice forked, and the hind-wings have 2 obliques. The siphunculi are very small, as long as or a little longer than wide, broadest at the base, and without constriction. The cauda is large and very long, with a constriction about the middle. The Brachysiphoniella genus is closely related to Brachycolus, but is distinguished by the structure of the siphunculi, and the larger cauda.
There is one, or possibly two, species of Brachysiphoniella. The best-known species, Brachysiphoniella montana (see below), is mainly anholocyclic on grasses, especially aquatic species. In Korea there is evidence of host alternation to Pyrus spp. It is distributed through much of East, South and South-east Asia, as well as Australia. The other species, Brachysiphoniella apiaca, feeds on wild celery (Apium graveolens) in China.
Brachysiphoniella montana (Asian waxy grass aphid) East Asia, Australia
Adult apterae of Brachysiphoniella montana (see two pictures below) are dirty greenish-brown in colour, but this is largely obscured by a thick coat of white mealy wax on the head, body and tibiae. Their antennae are dark greenish brown, less than half the body length and with the terminal process about twice as long as the base of antennal segment VI. The apical rostral segment is at most 1.3 times as long as wide at its base. Abdominal tergites I and VII are without marginal tubercles. The tibial hairs are short, not longer than the width of the tibia at midlength. The siphunculi are short, black, broad-based cones, not longer than wide at their base, with a distinct apical rim around a large terminal pore. The cauda is long, black and finger-like with a midway constriction, and bears 12-19 hairs. The body length of the adult Brachysiphoniella montana aptera is 1.1-1.9 mm.
Images above by permission, copyright Sunil Joshi & Poorani, J. Aphids of Karnataka (accessed 12/2/20).
We have been unable to find a description of the alate vivipara, although it is pictured in Noordam (2004). Immatures tend to appear grey, rather than white, because of a less dense wax coating.
Brachysiphoniella montana is found on the upper surface of grass leaves, usually near or in water. Host plants include Leersia (L. hexandra), Cynodon (C. plectostachyus), Eleusine, Microstegium, Miscanthus, Oryza, Panicum, Pennisetum and Phragmites. It is thought to be mainly anholocyclic but, at least in Korea and possibly Japan, there is evidence of host alternation to pear (Pyrus spp.). Brachysiphoniella montana is known from India, Bangladesh, Nepal, China, Taiwan, Vietnam, Korea, Japan, Philippines, Malaysia, Indonesia, and Australia.