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

Aphidinae : Macrosiphini : Myzus ajugae
 

 

Myzus ajugae

Bugle pseudogall aphid

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

Identification & Distribution

Myzus ajugae induces a pseudogall on bugle (Ajuga spp.) (see first picture below) by feeding on the upper surfaces of the leaves, causing the leaves to become tightly curved inwards. The apterae (see second picture below) vary in colour from brown to dirty yellowish green to dark green. The siphunculi are dusky brown, darker at the apex, and the cauda is brownish. The antennal terminal process is 3.2-4.0 times as long the base of antennal segment VI. The longest hair on antennal segment III is 0.3-0.6 times the basal diameter of that segment. The apical rostral segment (RIV+V) is 1.0-1.3 times the second hind tarsal segment (HTII), with 4-6 accessory hairs (cf. Myzus persicae, which has RIV+V 0.9-1.0 times HTII, with usually only 2 hairs). The siphunculi are 2.6-3.0 times the caudal length; they are slightly swollen on the distal half, with the diameter of the swollen part 1.2-1.4 times the diameter of the narrower basal half. The cauda has 4-6 hairs. Body length of adult Myzus ajugae apterae is 1.5-1.9 mm.

Images above copyright hhbrun under a creative common licence.

The images below show clarified slide mounts of an apterous and alate vivipara. The alate vivipara of Myzus ajugae has a solid pigmented area occupying the mid-abdominal dorsum from tergites III to VI, as well as further bars on adjoining tergites, much like Myzus persicae. The antennae are about the same length as the body, with a terminal process 3.4-3.9 times the base of antennal segment VI. There are 7-12 secondary rhinaria on segment III, with usually none on segments IV & V. The siphunculi are 2.1-2.2 times as long as the cauda.

Images above by permission of Roger Blackman, copyright AWP all rights reserved.

Myzus ajugae is monoecious on bugle (Ajuga spp.). The aphid is reputedly most often found on plants growing in deep shade. The species is holocyclic, with oviparae and apterous males developing in autumn. Myzus ajugae is found over most of Europe, but is very rare in some countries.

 

Other aphids on the same host

  • Myzus ajugae has been recorded on 3 Ajuga species (Ajuga genevensis, Ajuga orientalis, Ajuga reptans).

    Blackman & Eastop list 5 species of aphid as feeding on common bugle (Ajuga reptans worldwide, and provide formal identification keys (Show World list). Of those aphid species, Baker (2015) lists 5 as occurring in Britain (Show British list).

  • Myzus ajugae is the only species of aphid recorded on Ajuga orientalis.

  • The only other species of aphid found on Ajuga genevensis is Aulacorthum solani.

Acknowledgements

We especially thank hhbrun for putting his images of Myzus ajugae under a creative commons licence.

We have used information from Stroyan (1957) and Heie et al. (1994), along with information from Roger Blackman & Victor Eastop in Aphids on Worlds Plants. We fully acknowledge these authors, and those listed in the reference sections, 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

  • Heie, O.E. (1994). The Aphidoidea (Hemiptera) of Fennoscandia and Denmark. V. Family Aphididae: Part 2 of tribe Macrosiphini of subfamily Aphidinae. Fauna Entomologica Scandinavica 28 (p. 20).

  • Stroyan, H.L.G. (1957). Further additions to the British aphid fauna. Transactions of the Royal Entomological Society of London 109(2), 311-360. Abstract