Rabdophaga terminalis

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.^[1][2]

It is uncertain whether white larvae are the young larvae of R. terminalis or inquilines, Macrolabis saliceti and/or R. strobilina.^[2]

The gall has been found on the following species:

• Salix alba – white willow
• Salix babylonica – Babylon willow
• Salix caesia
• Salix excelsa
• Salix × fragilis – crack willow
• Salix pentandra – bay willow
• Salix purpurea – purple willow
• Salix triandra – almond willow
• Salix viminalis – osier
• Salix viridis

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