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Aphidinae : Aphidini : Aphis lupini


Aphis lupini

Western American lupin aphid

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

Identification & Distribution

Adult apterae of Aphis lupini are dusky olive to greenish black, shading to brown or black on the head. The legs are mostly light brown, and the siphunculi, anal plate, genital plate and cauda are dark. The antennae are rather uniformly dark, although sometimes the base of segment III is pale or dusky (cf. various polyphagous Aphis spp. whose segments III-V are mainly pale). The terminal process is less than twice as long as the base of antennal segment VI, and shorter than segment III. The rostrum reaches to between the second and third pairs of coxae. The apical rostral segment (RIV+V) is acute and quite long, 1.2-1.4 times the second hind tarsal segment (HTII) (cf. Aphis lupinehansoni in northwestern USA on Lupinus, which has RIV+V blunter, and about the same length as HTII). There are sclerotized dark dorsal bands on abdominal VII and VIII. The siphunculi are rather closely imbricated, cylindrical or slightly larger at bases, and with no polygonal reticulation (cf. Macrosiphum albifrons, Macrosiphum euphorbiae and Macrosiphum zionense on Lupinus, which all have a subapical zone of polygonal reticulation). The cauda is elongate, tapering, acute at the tip, and with only a slight constriction near the base; it is unusually hairy bearing 6-10 hairs on each side. The body length of adult Aphis lupini apterae is 2.0-3.0 mm. Newly deposited immatures are yellowish-brown; older immatures are green.

First image above copyright Andrew Jensen, second image copyright CBG Photography Group,
both under a Creative Commons License.

Alate viviparae of Aphis lupini are similar in colour and size to the aptera, or slightly smaller. Antennal segment III bears 3-6 round, flat secondary rhinaria, with none on segment IV. The veins of the forewings are darkened, and the pterostigma is dusky yellowish.

Image above copyright Andrew Jensen, under a Creative Common Licence.

Aphis lupini feeds on the leaves and stems of silvery lupin (Lupinus argenteus =decumbens). They are monoecious holocyclic, with small apterous males (see small aphid on back of female in picture above). Knowlton (1935) noted that whenever he found this species in Utah, apterous viviparous females were present in abundance. Jensen in Aphidtrek comments that the species appears to go through periods of abundance, but then for years afterwards seems to be incredibly rare. The Western American lupin aphid is found in the western states of the USA.


Other aphids on the same host

Aphis lupini has been recorded on one species of lupin (Lupinus argenteus including form decumbens).

Blackman & Eastop list 2 species of aphid as feeding on silvery lupin (Lupinus argenteus) worldwide, and provide formal identification keys (Show World list). Of those aphid species, Baker (2015) lists 1 as occurring in Britain (Show British list).


We are grateful to Andrew Jensen and the CBG Photography Group for making their images of Aphis lupini available for use under a creative commons licence.

We have used the species accounts given by Gillette & Palmer (1929), Knowlton (1935)), and Palmer (1952), together 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 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


  • Gillette, C.,P. & Palmer, M.A. (1929). New Colorado Aphididae. Annals of the Entomological Society of America 22(1), 1-32. (p. 18) Full text

  • Knowlton, G.F. (1935). Four Lupine aphids. Proceedings of the Entomological Society of Washington 37(5), 112-119. (p. 114) Full text

  • Palmer, M.A. (1952). Aphids of the Rocky Mountain Region: including primarily Colorado and Utah, but also bordering area composed of southern Wyoming, southeastern Idaho and northern New Mexico. Full text