Ceruraphis eriophori (Wayfaring tree - sedge aphid): identification, images, ecology, control

Ceruraphis eriophori is a medium-sized, oval, aphid. The antennae are short, only 0.29-0.37 times their body length. The dorsum of the fundatrix on the primary host (shown below) has extensive dark sclerotization. The same is true for Ceruraphis eriophori aptera on their secondary host. The siphunculi are black and are more than twice as long as the very short conical cauda. The body length of the Ceruraphis eriophori fundatrix is 2.5-3.0 mm, and that of the aptera on the secondary host is 2.0-2.8 mm.

Ceruraphis eriophori (wayfaring tree - sedge aphid) aptera & nymphs in a gall on Viburnum lantana (wayfaring tree) at Alciston, East Sussex, UK on 5/5/12 at 15.53 h.

The nymphs produced by the fundatrix are violet coloured (see first picture above) and all develop to alates (see second picture above) which migrate to the secondary host.

The clarified slide mounts below are of adult viviparous female Ceruraphis eriophori (on primary host) : wingless, and winged.

Ceruraphis eriophori (on primary host). Clarified slide mount of adult viviparous aptera.

The wayfaring tree - sedge aphid host alternates between Viburnum spp. (especially wayfaring tree (Viburnum lantana)) and various sedges (Carex spp.). On the wayfaring tree the aphid lives in a pseudogall of curled leaves. Ceruraphis eriophori is found in Europe and northern India and has been introduced to North America.

Biology & Ecology:

The overwintering eggs on wayfaring tree hatch in spring, and the nymphal fundatrices feed on the young shoots. This makes the leaves shrivel and curl downwards, thus enclosing the aphids in a pseudogall. These pseudogalls are very conspicuous on the tree in spring (see pictures below).

Gall caused by Ceruraphis eriophori (wayfaring tree - sedge aphid) on Viburnum lantana (wayfaring tree) at Anscombe Bottom, East Sussex on 26/4/12 at 17.38 . Pseudogall caused by Ceruraphis eriophori (wayfaring tree - sedge aphid) on Viburnum lantana (wayfaring tree). Black Rock, Mendip Hills, Somerset, UK on 25/4/09 at 14.39 h

The developing fundatrices are greyish before maturing to the black adult fundatrices (see first picture below). The fundatrices then produce characteristic violet-coloured nymphs (see second picture below) which fill the gall.

Ceruraphis eriophori (wayfaring tree - sedge aphid) developing (grey) and mature (black) fundatrices on Viburnum lantana (wayfaring tree) at Black Rock, Mendip Hills, Somerset, UK on 25/4/09 at 14.33 h

Ceruraphis eriophori produce large amounts of honeydew, which can make the galls and surrounding leaves very sticky.

Ceruraphis eriophori (wayfaring tree - sedge aphid) developing nymphs and adult fundatrix on Viburnum lantana (wayfaring tree) at Alciston, East Sussex on 5/5/12 at 15.54 h

Sometimes (but not always), Ceruraphis eriophori are attended by ants feeding on the excreted honeydew. We have found two species of ants attending Ceruraphis eriophori, jet black ants (Lasius fuliginosus) (see first picture below) and a Myrmica sp. (see second picture below).

Ceruraphis eriophori (wayfaring tree - sedge aphid) attended by Lasius fuliginosus (jet black ants) on Viburnum lantana (wayfaring tree) at Alciston, East Sussex on 5/5/12 at 15.49 h.

Where ants are present, we have found much larger colonies of Ceruraphis eriophori in the galls. All the violet-coloured nymphs mature to alates (see picture below) which migrate to the secondary hosts.

Ceruraphis eriophori (wayfaring tree - sedge aphid) alate taking off from Viburnum lantana (wayfaring tree) at Anscombe Bottom, East Sussex on 7/5/13 at 17.03 h.

Unfortunately we have not yet found Ceruraphis eriophori on their secondary host (hence no pictures), although it must be fairly common given the abundance of the species on the primary host in some locations.

There seems to be very little published information on Ceruraphis eriophori. In New Brunswick, USA MacGillivray(1960) compared the taxonomy and biology of the invasive Ceruraphis eriophori with the indigenous Neoceruraphis viburnicola. Both could be found in spring and autumn in the curled leaves of their Viburnum primary hosts.

Damage and control

Ceruraphis eriophori is not considered to cause any economic damage in Europe. However, in America it is an alien invasive species, and is considered a potential threat to the long term survival of the endangered false hop sedge (Carex lupuliformis) (Environment Canada, 2014 ).

Acknowledgements
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).

Useful weblinks

References

Environment Canada (2014). Recovery Strategy for the False Hop Sedge (Carex lupuliformis) in Canada. Species at Risk Act Recovery Strategy Series. Environment Canada, Ottawa. v + 23 pp. Full text
MacGillivray, M.E. (1960). Notes on life-history and taxonomy of Ceruraphis eriophori (Wlk.) and Neoceruraphis viburnicola (Gill.), and a description of the apterous viviparous female of Neoceruraphis viburnicola (Gill.) (Homoptera: Aphididae). The Canadian Entomologist 92(9), 704-707. Abstract

Ceruraphis eriophori

Wayfaring tree - sedge aphid

Identification & Distribution:

Biology & Ecology:

Damage and control

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References