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Coriander aphidOn this page: Identification & Distribution Other aphids on the same host
Identification & Distribution
Adult apterae of Hyadaphis coriandri are rather small, broadly oval, somewhat short-legged, mainly dirty yellowish green, with dark-green dorsal mottling, and rust-red patches around the bases of short, dark-brown siphunculi. The first image below shows immature apterae with dusky siphunculi, and the second shows a colony of mixed age apterae on the umbels of their secondary host. The body is variably dusted with white mealy wax. The antennae have 5-6 segments, and are 0.39-0.4 times as long as the body; the terminal process is 1.3-2.3 times the length of the base of last antennal segment (but see note below). There are no secondary rhinaria on the antennae. The apical rostral segment is shorter than the second hind tarsal segment. There is no dark transverse bar present beneath the rostrum (cf. Hyadaphis foeniculi, which has a dark transverse bar present beneath the rostrum). The tergites are almost completely membranous. The siphunculi are barrel-shaped, strongly swollen at their base, 1.6-2.7 times their minimum diameter on the basal half, and 0.6-0.82 times as long as the cauda (cf. Hyadaphis foeniculi which has clavate (=club-shaped) siphunculi, 3.1-5.1 times their minimum diameter on the basal half, and 0.88-1.4 times the caudal length). The cauda is conspicuously long and bears 6-7 hairs. The body length of adult Hyadaphis coriandri apterae is 1.3-2.1 mm.
Note: The description above refers to apterae on the secondary host. All adult apterae on the primary host are fundatrices, which only produce emigrant alatae (= spring migrants). The fundatrices have 5-segmented antennae with a terminal process 0.8-0.9 times the base of antennal segment VI.
The alate Hyadaphis coriandri (not pictured alive, but see second picture below for clarified mount) has a pale-green abdomen with black dorsal markings, and reddish-brown patches around the siphuncular bases. The siphunculi are dark and the cauda pale.
Images of clarified mounts, above, copyright Brendan Wray under a Creative Commons License.
The primary host of Hyadaphis coriandri in west Asia is honeysuckle (Lonicera spp.), although the species is anholocyclic over much of its range. All the progeny of the fundatrix migrate to secondary hosts, which are numerous species & genera of Apiaceae including coriander (Coriandrum), cumin (Cuminum), and carrot (Daucus). They live and feed mostly on the umbels. Coriander is particularly susceptible to their attack, and in India coriander aphid is considered a key pest of coriander in the spring. Occasionally plants outside the Apiaceae are colonised, such as mint (Mentha, Lamiaceae), amaranth (Amaranthus, Amaranthaceae), and soy bean ( (Glycine max, Fabaceae). It has not been implicated in the transmission of any plant virus. Hyadaphis coriandri is probably of West & Central Asian origin where the holocycle still exists (Iran, Kazakhstan). Hyadaphis coriandri now occurs in Southern Europe, the Mediterranean region, the Middle East, most of Asia, and Africa, and has more recently been introduced to the United States in Florida, California & Hawaii, and to South America in Argentina & Peru.
Other aphids on the same host
Hyadaphis coriandri feeds on 5 honeysuckle species (Lonicera karataviensis, Lonicera microphylla, Lonicera nummulariifolia, Lonicera quinquelocularis, Lonicera tatarica).
Hyadaphis coriandri feeds on 1 coriander species (Coriandrum sativum).
Hyadaphis coriandri feeds on 1 Daucus species (Daucus carota).