''Rabdophaga strobilina'' is a

gall midge Cecidomyiidae is a family of flies known as gall midges or gall gnats. As the name implies, the larvae of most gall midges feed within plant tissue, creating abnormal plant growths called galls. Cecidomyiidae are very fragile small insects us ...

which forms

gall Galls (from the Latin , 'oak-apple') or ''cecidia'' (from the Greek , anything gushing out) are a kind of swelling growth on the external tissues of plants, fungi, or animals. Plant galls are abnormal outgrowths of plant tissues, similar to be ...

s on the buds of some species of

willow Willows, also called sallows and osiers, from the genus ''Salix'', comprise around 400 speciesMabberley, D.J. 1997. The Plant Book, Cambridge University Press #2: Cambridge. of typically deciduous trees and shrubs, found primarily on moist s ...

(''Salix'' species). It was first described by

Hermann Loew Friedrich Hermann Loew (19 July 1807 – 21 April 1879) was a German entomologist who specialised in the study of Diptera, an order of insects including flies, mosquitoes, gnats and midges. He described many world species and was the first specia ...

in 1850.

Description

The gall is green, reddish, later black but never hairy. The leaves of the terminal bud are slightly thickened, sometimes crinkled and curled into an elongate gall, which can be hidden by older leaves. Inside the gall is an elongate cavity with orange or reddish larvae numbering from one to forty. It is uncertain whether white larvae are the young larvae of ''R. terminalis'' or inquilines, '' Macrolabis saliceti'' and/or '' R. strobilina''. The gall has been found on the following species: * '' Salix alba'' – white willow * '' Salix babylonica'' – Babylon willow * '' Salix caesia'' * ''

Salix excelsa ''Salix excelsa'' is a species of flowering plant in the willow family Salicaceae. It is native to the Caucasus, Central Asia (except Kyrgyzstan), Iran, Afghanistan, and Pakistan, and has been introduced to the Levant, Yemen, the Himalayas, and I ...

'' * ''

Salix × fragilis ''Salix'' × ''fragilis'', with the common names crack willow and brittle willow, is a hybrid species of willow native to Europe and Western Asia. It is native to riparian habitats, usually found growing beside rivers and streams, and in marshe ...

'' – crack willow * ''

Salix pentandra Willows, also called sallows and osiers, from the genus ''Salix'', comprise around 400 speciesMabberley, D.J. 1997. The Plant Book, Cambridge University Press #2: Cambridge. of typically deciduous trees and shrubs, found primarily on moist so ...

'' – bay willow * ''

Salix purpurea ''Salix purpurea'', the purple willow purpleosier willow or purple osier, is a species of willow native to most of Europe and western Asia north to the British Isles, Poland, and the Baltic States.Flora Europaea''Salix purpurea''/ref>Meikle, R. D ...

'' – purple willow * ''

Salix triandra ''Salix triandra'', with the common names almond willow, almond-leaved willow or black maul willow, is a species of willow native to Europe and Western and Central Asia. It is found from south-eastern England east to Lake Baikal, and south to Sp ...

'' – almond willow * ''

Salix viminalis ''Salix viminalis'', the basket willow, common osier or osier, is a species of willow native to Europe, Western Asia, and the Himalayas.Meikle, R. D. (1984). ''Willows and Poplars of Great Britain and Ireland''. BSBI Handbook No. 4. .Rushforth, K ...

'' – osier * '' Salix viridis''

Distribution

The insect or gall has been found in Belgium and the United Kingdom.

References

terminalis Nematoceran flies of Europe Gall-inducing insects Insects described in 1850 Taxa named by Hermann Loew Willow galls {{Bibionomorpha-stub