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 : Macrosiphum valerianae
 

 

Macrosiphum valerianae

Crimson highland aphid

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

Identification & Distribution

Adult apterae of Macrosiphum valerianae (see first picture below) are dark reddish, purplish, or nearly black, with very long dark antennae and siphunculi. The dorsum is often pruinose (= dusted with fine white wax powder), especially in immatures. Secondary rhinaria are confined to the basal third of segment III, arranged in a straight row, numbering from 3 to 8, generally 5 or more (cf. Macrosiphum rosae which has 10-36 rhinaria on segment III, not in a row). The terminal process is 6.5 times the base of antennal segment VI, and hairs on apical half of third antennal segment are either equal to or longer than the width of the segment. The rostrum is short, failing to reach the mesocoxae, and the apical rostral segment is 0.80-0.95 times the second hind tarsal segment. The prothorax is without marginal tubercles. The coxae and trochanters are pale; femora are pale at the base usually shading to dark, and tibiae & tarsi are dark (cf. Macrosiphum euphorbiae which has rather pale femora and tibiae - but note some specimens of Macrosiphum valerianae can be rather pale). There are usually distinct (but pale) presiphuncular sclerites present (cf. Macrosiphum euphorbiae which does not have presiphuncular sclerites). The siphunculi are 1.03-1.30 times antennal segment III and 1.9-2.2 times the cauda (cf. Macrosiphum pallidum which has siphunculi 0.73-0.95 times antennal segment III, and 1.2-1.7 times the cauda). The cauda is light yellowish brown, and quite long. The body length of adult apterae is 2.1-4.0 mm.

Note: Macrosiphum kiowanepus (sometimes mispelt as kiowanepum) described by Hottes (1933) is a synonym.

Images above copyright Andrew Jensen, under a creative common licence.

The alate Macrosiphum valerianae is dark red, rendered slightly bluish by the wax powder on the dorsum; antennae are dark apart from segments I, II & base of III which are dusky. Secondary rhinaria are confined to antennal segment III, arranged in a straight row, numbering from 8 to 19 (averaging 13). The long black siphunculi taper gradually from a rather wide base to the apex, and cauda is pale.

Macrosiphum valerianae is a polyphagous species, colonising leaves and stems of a wide range of host plants: Apiaceae (Lomatium), Asparagaceae (Camassia), Asteraceae (Hymenoxys, Rudbeckia, Taraxacum), Brassicaceae (Arabis), Melanthiaceae (Zigadenus), Onagraceae (Epilobium), Rosaceae (Geum, Potentilla, Rosa), Scrophulariaceae (Pedicularis, Penstemon) and Valerianaceae (Valeriana). It is monoecious holocyclic, and may utilise various overwintering hosts. Macrosiphum valerianae is found in mountains and foothills throughout western USA and Canada.

 

Other aphids on the same host

Macrosiphum valerianae has been recorded on 3 Geum species of (Geum macrophyllum, Geum rivale, Geum triflorum).

Macrosiphum valerianae has been recorded on 1 species of Potentilla (Potentilla bakeri).

It is the only aphid species recorded for that plant.

Macrosiphum valerianae has been recorded on 1 species of Zigadenus (species unidentified, and probably now in a different genus within the Melanthiaceae).

Acknowledgements

We are grateful to Andrew Jensen for making his images of Macrosiphum valerianae available for use under a creative commons licence.

We have used the species account given by Hottes (1933) (as Adactynus kiowanepus), together with information from Jensen (2012), and 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 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

  • Hottes, F.C. (1933). Descriptions of Aphididae from Western Colorado. Proceedings of the Biological Society of Washington 46, 1-24 (p. 14) Full text

  • Jensen, A.S. (2012). Macrosiphum (Hemiptera: Aphididae) Update: One new species, one synonymy, and life cycle notes. Proceedings of the Entomological Society of Washington 14(2), 205-216.Abstract