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Aphidinae : Macrosiphini : Acyrthosiphon boreale
 

 

Acyrthosiphon boreale

Northern cinquefoil aphid

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

Identification & Distribution

Adult apterae of Acyrthosiphon boreale are green with the anterior part of the body yellowish. The dorsal cuticle is slightly sclerotized and wrinkled, but not pigmented. Their antennal tubercles are well developed with diverging, rough inner sides. The antennae are 0.7-1.1 the body length and the terminal process is 4.6-6.0 times longer than the base of the sixth antennal segment. The third antennal segment of the aptera has 2-14 (rarely less than 5) slightly raised secondary rhinaria mainly on the basal half (cf. Acyrthosiphon malvae ssp. potha, which has 1-9 (rarely more than 5) rhinaria on III). The siphunculi are cylindrical with a rather well developed flange. The siphunculi are 0.21-0.30 times the body length and 1.5-2.6 times longer than the cauda. The cauda is rather thick, not constricted and bearing 7-11 hairs. The body length of apterous Acyrthosiphon boreale is 2.7-3.2 mm.

The alate viviparaAcyrthosiphon boreale has large marginal sclerites partly or nearly fused with large pleural intersegmental sclerites, with cross bars on tergites VII and VIII. The antennae, siphunculi and cauda are dark. The antennae bear 5-17 secondary rhinaria on segment III.

The fundatrix is similar to the aptera, but the terminal process is only 2.7 times longer than the base of the sixth antennal segment. Males are apterous.

Acyrthosiphon boreale lives year round on cinquefoils (Potentilla) species. It has a boreo-alpine distribution including northern Europe, Greenland and Canada.

 

Biology & Ecology:

We have only found Acyrthosiphon boreale on one occasion, a colony of the aphids on marsh cinquefoil (Potentilla palustris) in Inverness-shire in Scotland.

The colony comprised several adult apterae feeding on the stems and leaves of the host plant.

They were depositing first instar nymphs on the leaves close to the leaf mid-vein (see picture below).

Heie (2015) notes that Acyrthosiphon boreale can be present in huge numbers on Potentilla species.

 

Other aphids on same host

Acyrthosiphon boreale has been recorded on 23 Potentilla species (Potentilla anglica, Potentilla anserina, Potentilla argentea, Potentilla aurea, Potentilla blaschkeana, Potentilla chrysantha, Potentilla collina, Potentilla crantzii, Potentilla erecta, Potentilla hispanica, Potentilla hypactica, Potentilla impolita, Potentilla norvegica, Potentilla ornithopodioides, Potentilla palustre, Potentilla patlua, Potentilla pedata, Potentilla puberula, Potentilla recta, Potentilla reptans, Potentilla sericea, Potentilla supina, Potentilla tephroleuca).

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. (2010). Aphids - Aphidinae (Macrosiphini). Handbooks for the identification of British insects 2(7). Royal Entomological Society, London.

  • Heie, O.E (2015). Aphidomorpha. In:Bocher, J. et al. The Greenland Entomofauna. An identification manual of insects, spiders and their allies. Brill. Leiden, The Netherlands.