Biology, images, analysis, design...
|"It has long been an axiom of mine that the little things are infinitely the most important" |
Resplendent lupin aphidOn this page: Identification & Distribution Other aphids on the same host
Identification & Distribution
Adult apterae of Macrosiphum zionense (see pictures below) are green, yellow or orange, with a dusting of white wax especially on the thoracic segments. The antennae, tibiae and siphunculi are black (cf. Macrosiphum albifrons & Macrosiphum euphorbiae, both on Lupinus, which have the antennae, tibiae & siphunculi mainly pale). The antennae are longer than the body, with antennal segment IV nearly as long as segment III (cf. Aphis lupini, which has antennae shorter than the body). Antennal segment III bears 2-3 secondary rhinaria (cf. Macrosiphum albifrons, which has 17-40 small secondary rhinaria on segment III). The hairs on antennal segment III are more than 0.5 times the basal diameter of that segment. The siphunculi have a subapical zone of polygonal reticulation (cf. Aphis lupini which has no zone of polygonal reticulation on its siphunculi). The cauda is long and pale. The body length of adult Macrosiphum zionense apterae is about 4.1 mm.
The first picture below shows a preserved adult apterous vivipara of Macrosiphum zionense. The second picture shows a fundatrix (=foundress), in other words a parthenogenetic female produced from an (overwintering) fertilized egg. This fundatrix is of the golden-yellow form; there is also a bright orange form. Jensen waxes eloquent about this aphid with its "beautiful orange colour, with striking dark siphunculi and tibiae".
The alate Macrosiphum zionense (not pictured) is green. The antennae are long and black, except the proximal ends of III and distal tips of III, IV, and V, which are pale. Antennal segment III bears 25 to 27 secondary rhinaria. The antennal tubercles are well developed. The rostrum reaches the second pair of coxae. The siphunculi are black, with about the distal 0.15 reticulated. The cauda is large and pale.
Macrosiphum zionense is monoecious holocyclic on lupin (Lupinus spp.) and golden pea (Thermopsis spp.). For most of the year these aphids are found on the upper plant stems, but later in fall as the plants senesce, the sexuales start to develop. These can be found on the lower stems of the plants, just above the soil level. The resplendent lupin aphid lives in the mountains of the interior in western USA (Utah, Idaho, Oregon, Washington).
Other aphids on the same host
Macrosiphum zionense has only been recorded from lupin species (Lupinus & Thermopsis spp.). It has been found on at least 24 Lupinus species, albeit it dose not appear to be specific to any one of them.
Macrosiphum zionense has been recorded from 3 "false lupin" species (Thermopsis divaricata, Thermopsis gracilis, Thermopsis montana).