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Dysaphis hirsutissima

Hairy mealy root aphid

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

Identification & Distribution

Adult apterae of Dysaphis hirsutissima are bluish-green with a dark dorsal pattern of paired sclerites and cross-bands (see first picture below). Dorsal hairs are long and very numerous on each tergite. The longest hairs on antennal segment III are 57-97 μm long, 2.5-3.7 times the basal diameter of that segment (cf. Dysaphis anthrisci which has longest hairs on antennal segment III at 26-72 μm and dorsal hairs less numerous and shorter).

They are usually attended by ants (see second picture above). The micrographs below show an adult Dysaphis hirsutissima (dorsal and ventral) preserved in ethanol.

The clarified slide mounts below are of adult viviparous female Dysaphis hirsutisima : wingless, and winged.

Micrographs of clarified mounts  by permission of Roger Blackman, copyright AWP  all rights reserved.

Dysaphis hirsutissima is found on the stem base and in leaf sheaths of cow parsley (Anthriscus sylvestris). It has only been recorded from Britain, Denmark, the Netherlands, Sweden, Switzerland and Italy, but is probably widespread over most of Europe.

 

Biology & Ecology

We found this species on an isolated plant of cow parsley at Birling Gap on the East Sussex coast. The plant itself was nearly dead, although the stem was still green.

The Dysaphis colony was partly below the soil surface, with the upper part tented with soil by Myrmica ants.

Immatures of Dysaphis hirsutissima (see picture below) are also blue-green and are very hairy like the adult, but they lack the black markings. They also have an orange patch around each siphunculus as do immatures of several other Dysaphis species.

 

Other aphids on the same host

Blackman & Eastop list 20 species of aphid  as feeding on cow parsley (Anthriscus sylvestris) worldwide, and provide formal identification keys.

Of those aphid species, Baker (2015)  lists 12 as occurring in Britain: Aphis brohmeri Aphis fabae,  Aulcaorthum solani,  Cavariella aegopodi,  Cavariella archangelicae,  Cavariella pastinacae,  Dysaphis anthrisci, Dysaphis crataegi,  Dysaphis hirsutissima, Hyadaphis foeniculi,  Macrosiphum euphorbiae,  Macrosiphum gei  and Pemphigus protospirae. 

The image below shows a colony of Aphis fabae on the upper stem of the same plant as a Dysaphis hirsutissuma colony shown above. 

Acknowledgements

Our particular thanks to Roger Blackman for images of his clarified slide mounts.

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).

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