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Hyadaphis foeniculi

Fly honeysuckle aphid, Fennel aphid

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

Identification & Distribution:

Hyadaphis foeniculi apterae on the primary host are greyish-green or light green with the middle part of the dorsum darker green. Their colour is rather more variable on the secondary host and reddish brown spots are often present at the siphuncular bases. The legs and antennae of Hyadaphis foeniculiare dark. The prosternal sclerite is 1.4 to 2.6 times wider than long. The siphunculi are black and slightly swollen and are 1.05-1.4 times the length of the cauda. The body length is 1.3 to 2.6 mm on the primary hosts, 1.4-2.0 mm on the secondary hosts..

The alate often has 1-4 secondary rhinaria on the fifth antennal segment.

N.B. The characteristics of some Hyadaphis foeniculi populations, we have found, appear to be intermediate between Hyadaphis passerinii and Hyadaphis foeniculi. Hence we cannot be certain about their identification. Some authorities only give Hyadaphis passerinii and Hyadaphis foeniculi subspecific status.

The clarified slide mounts below are of adult viviparous female Hyadaphis foeniculi : wingless, and winged.

Micrographs of clarified mounts  by permission of Roger Blackman, copyright AWP  all rights reserved.

Hyadaphis foeniculi host alternates. It mainly uses fly-honeysuckle (Lonicera xylosteum) as its primary host. Infested leaves are curled upwards in spring. Hyadaphis foeniculi migrates to various Apiaceae where it feeds on stems, leaves and flowers. Secondary hosts include hemlock (Conium), fennel (Foeniculum) and Pastinaca. It is widespread in Europe, especially in the north. Hyadaphis foeniculi extends eastwards to Turkey and Iraq and is also found in North America and Brazil.


Other aphids on same host:

Primary host

Hyadaphis foeniculi has been recorded from 16 Lonicera species, and (occasionally) on several Symphoricarpos species. 

Secondary hosts


Our particular thanks to Roger Blackman for images of his clarified slide mounts.

We have made provisional identifications from high resolution photos of living specimens, along with host plant identity. In the great majority of cases, identifications have been confirmed by microscopic examination of preserved specimens. We have used the keys and species accounts of Blackman & Eastop (1994)  and Blackman & Eastop (2006)  supplemented with Blackman (1974) , Stroyan (1977) , Stroyan (1984) , Blackman & Eastop (1984) , Heie (1980-1995) , Dixon & Thieme (2007)  and Blackman (2010) . We fully acknowledge these authors 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).

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