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

 

 

Aphis veratri

European hellebore aphid

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

Identification & Distribution

The original description of adult apterae of Aphis veratri states they are black, not shining, with a slight greyish wax bloom. They have since been redescribed as dark greenish-brown. Our (sadly rather blurred) pictures suggest they are somewhat variable in colour varying from reddish-brown to black. The antennal terminal process is 2.3-3.4 times the length of the base of antennal segment VI. Antennal segment III has 8-12 hairs. The apical rostral segment (RIV+V) is 1.2-1.7 times the length of the second hind tarsal segment (HTII). There are usually marginal tubercles on abdominal segments II-IV as well as on I & VII. The siphunculi are 0.8-2.1 times the length of the cauda. The body length of an adult aptera is 1.5-2.3 mm.

On the basis of transfer experiments, Müller & Horatschek (1980) cast doubt on the validity of Aphis veratri as a species, and suggested that that the black aphids found on Veratrum album were in fact Aphis fabae cirsiiacanthoidis. Jörg & Lampel (1996), however, using enzyme electrophoresis, established that Aphis veratri is a good species within the black aphid group, forming a very isolated subgroup with Aphis cacaliasteris, an aphid that feeds only on a few members of the Asteraceae. Note we cannot be certain of the identity of the aphids in the picture below (a mixture of oviparae and viviparae found in Switzerland on Veratrum leaves with a predatory cecidomyiid larva) as specimens were not collected. But the feeding site, the lack of white wax markings on immatures, and the presence of marginal tubercles (discernible on some specimens), make it very likely to be Aphis veratri rather than Aphis fabae.

Both images above copyright Alan Outen, all rights reserved.

Aphis veratri lives only on hellebores (Veratrum species), mainly the white hellebore (Veratrum album), where it is attended by ants. It feeds on the undersides of the leaves (but not on the upper stem and inflorescences where Aphis fabae may be found). There are very few aphids that will feed on white hellebore, probably because of the high levels of toxic alkaloids to which Aphis veratri is doubtless adapted. It does not host alternate. Sexual forms may be found in late summer. Aphis veratri is found in much of Europe but not in Scandinavia, Britain or Iberia.

 

Other aphids on the same host

Aphis veratri has been recorded on 4 species of the Veratrum genus (Veratrum album, Veratrum lobelianum, Veratrum nigrum and Veratrum viride).

Blackman & Eastop list only 3 species of aphid as feeding on white hellebore (Veratrum album) worldwide, and provide formal identification keys.

Baker (2015) lists only 2 of these species as occurring in Britain: Aphis fabae and Aphis fabae ssp. mordvilkoi. (Aphis veratri has not yet been recorded from Britain.)

 

Damage and control

Veratrum album (see picture below) is an important weed on grazed montane grasslands. It exhibits acute toxicity to mammals, and locally displaces fodder plants.

Image copyright Isidre blanc under a Creative Commons Attribution-Share Alike 4.0 International License

Schaffner et al. (2001) review the available information on the ecology of Veratrum album and its herbivores, including Aphis veratri, and explores prospects for weed biological control.

Acknowledgements

We especially thank Alan Outen (Bedfordshire Invertebrate Group) for the images above.

We have made provisional 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

  • Jörg, E. & Lampel, G. (1996) . Enzyme electrophoretic studies on the Aphis fabae group (Hom., Aphididae). Journal of Applied Entomology 120 (1-5), 7-18. Full text

  • Müller, V.F.P. & Horatschek, A. (1980). Zur Taxonomie der Blattlaus Aphis veratri Walker, 1852. Mitteilungen des Naturwissenschaftlichen Vereines fur Steiermark 110, 163-170 Google Scholar

  • Schaffner, U. et al. (2001) Veratrum album in montane grasslands: a model system for implementing biological control in land management practices for high biodiversity habitats. Biocontrol News and Information 22(1), 19-28. Full text