InfluentialPoints.com
Biology, images, analysis, design...
Aphids Find them How to ID AphidBlog
"It has long been an axiom of mine that the little things are infinitely the most important" (Sherlock Holmes)

Search this site

Aphididae : Chaitophorinae : Siphini : Sipha
 

 

Genus Sipha

Bristly grass aphids

On this page: Sipha elegans maydis

Sipha [Siphini]

Sipha are medium-sized oval aphids that have conspicuous spine-like hairs. They have 5-segmented antennae and a sclerotic upper surface. Their short siphunculi are stump-shaped. The four species of the nominate subgenus Sipha have a knobbed cauda, and the eight species of subgenus Rungsia have a broadly rounded cauda.

Sipha feed on grasses. Some Sipha species are largely restricted to particular grass genera or even species thereof, whilst other Sipha are polyphagous. Several species are restricted to wetland or coastal habitats.

 

Sipha elegans (Bristly olive grass aphid)

Adult apterae of Sipha elegans are usually brown to yellowish brown (see first picture below) or in cooler conditions olive green (see second picture below), with rows of spiny hairs. There is a paler spinal stripe (more apparent on immatures), and dark transverse intersegmental markings (cf. Sipha flava, which are usually bright yellow with only dusky intersegmental markings). The antennae are quite short, only 0.37-0.39 times the body length, with their terminal process 1.70-2.10 times as long as the base of antennal segment VI (cf. Sipha flava, which has somehat longer antennae at 0.45-0.54 times the body length). The apical rostral segment (RIV+V) is 0.50-0.62 times the length of the second hind tarsal segment (HTII). The siphunculi are small shallow pigmented cones. The cauda is broadly rounded (cf. Sipha flava, which has a cauda which has a conical base and a rounded, knobbed apex). The body length of adult Sipha elegans apterae is 1.4-2.1 mm. Immatures (see second picture below) are yellow-green speckled with rows with dusky spots.

Both images above by permission, copyright Jessica Joachim, all rights reserved.

The alate Sipha elegans (see second and third pictures below) has a black head and thorax, and a brownish yellow abdomen with dark sclerites.

Sipha elegans feeds on a wide range of grasses and cereals including (for example) Ammophila, Festuca and Triticum. On grass it produces characteristic feeding damage - the leaf blades roll upwards and yellow-brown patches develop (see pictures below). They are usually attended by ants (see second picture below). Sipha elegans is widely distributed over the world. It is native to the Palearctic from Europe, across Asia to China and Western Siberia. It is also well-established in the northern parts of the USA.

Read more...

 

Sipha maydis (Bristly black grass aphid)

The dorsum of the adult Sipha maydis aptera (see shiny black aphid nearest the ant in picture) is shining dark brown to blackish over the sclerotized areas. The antennal terminal process is less than 1.5 times as long as base of antennal segment 5. The apical rostral segment is 0.10-0.11 mm long, with 2- 3 subsidiary hairs. The adult body length is l.0-2.l mm.

Image copyright Adam Polednicek, all rights reserved.

The alate Sipha maydis (see picture above) has a solid sclerotic carapace extending over abdominal tergites 4-7, and including the siphuncular bases and the marginal sclerites of tergites 6-7. Abdominal tergites l-3 have separate dark bands, becoming narrower towards the front. Developing alatae (see the three larger wingless individuals in the picture above) are greenish on the thoracic area with a dull black abdomen and a characteristic orange-pinkish spinal stripe.

The bristly black grass aphid feeds on numerous species of grasses (Poaceae). It is mostly found on the upper sides of leaf blades, near the base, but also occurs on the stems or flowers. It is usually attended by ants as in the picture. It probably overwinters parthenogenetically in most areas, but apterous males have been reported in some countries. Sipha maydis is found in Europe and much of Asia, and more recently in North and South America. It can reach pest numbers on some cereal crops like barley.

Read more...

Acknowledgements

Whilst we make every effort to ensure that identifications are correct, we cannot absolutely warranty their accuracy. We have mostly made identifications from high resolution photos of living specimens, along with host plant identity. In the great majority of cases, identifications have been confirmed by microscopic examination of preserved specimens. We have used the keys and species accounts of Blackman & Eastop (1994) and Blackman & Eastop (2006) supplemented with Blackman (1974), Stroyan (1977), Stroyan (1984), Blackman & Eastop (1984), Heie (1980-1995), Dixon & Thieme (2007) and Blackman (2010). We fully acknowledge these authors 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).

Useful weblinks

References

  • Blackman, R.L. & Eastop, V.F. (2006). Aphids on the world's herbaceous plants and shrubs. Vols 1 and 2. John Wiley & Sons.