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Dark saltmarsh grass aphidOn this page: Identification & Distribution Other aphids on the same host
Identification & Distribution
Adult apterae of Atheroides brevicornis have a very elongated oval, nearly linear blackish-brown body. The head is semicircular with the front convex. The antennae are very short, 4 or 5-segmented, and only 0.14-0.17 times the body length (cf. Atheroides serrulatus, Atheroides hirtellus and Atheroides doncasteri, which all have the antennae greater than 0.20 times the body length). The terminal process is stumpy, about 0.5 times as long as the last antennal segment. The head and prothorax are fused, but their suture is very distinct. The mesothorax, metathorax and first abdominal tergite are free; abdominal tergites II-VII are fused, the second sometimes partly free; tergite VIII is semicircular and free. The dorsum is strongly sclerotic, usually uniformly dark, very coarsely corrugated, covered with club-shaped or inverse bottle-shaped hairs with blunt, sometimes emarginate (=notched at the margin) apices. The hair bases look like perforations of the dark sclerite. Tergite VIII has a number of thick, long, spiny hairs on large bases along the margin; the two longest stand rather far apart, with two club-shaped or cylindrical hairs between them. The siphunculi are reduced to very small pores on the anterior margin of tergite V (cf. Laingia psammae, which has siphunculi as slightly raised pores with sclerotic rims on abdominal tergite VI). The body length of adult Atheroides brevicornis apterae is 1.5-2.4 mm.
First image above copyright Tim Hodge, all rights reserved.
The second image above show an adult aptera of Atheroides brevicornis ventral in isopropyl alcohol. The image below is a lateral close-up of its antenna.
The alate (not pictured) has the head and thorax sclerotic and dark. The abdomen is mostly membranous with paired, very large, usually fused spinal sclerites; pleural sclerites are often absent and marginal sclerites are large. Tergites VII and VIII are uniformly sclerotic. Their antennae are as in the apterae, with 4, rarely 5, segments, but with the third segment bearing 2-4 secondary rhinaria.
The image below shows an Atheroides brevicornis apterous viviparous female dorsal (upper half) and ventral (lower half).
Atheroides brevicornis lives in rows on the upper sides of grasses especially those growing in salt-marsh habitats such as Deschampsia cespitosa, Puccinellia spp., Festuca ovina and Festuca rubra. There is no host alternation and sexual forms develop in autumn (see Wieczorek, 2010). The dark saltmarsh grass aphid is found in coastal habitats around northern Europe and the Black Sea, as well as in salty pond-side habitats. Hille Ris Lambers (1939) notes that Atheroides brevicornis is extremely common along the muddy seashores of the Netherlands where it feeds on common saltmarsh grass (Puccinellia maritima = Festuca thalassica) and reflexed saltmarsh grass (Puccinellia distans = Festuca distans), the two typical species of grass growing there.
Other aphids on the same host