Ramshorn Gall - Andricus aries f. agamic
The asexual gall produced by this wasp in the buds of native Quercus species is said to resemble the horns of a Ram in its shape. The gall commonly forms a 'chimera' with another gall-causing species, causing oddly-shaped galls, and the presence of the inquiline wasps Synergus spp can also change the shape of the gall, causing enlargement of the bulbous base.
[Note: The sexual gall is reported to be on the catkins of evergreen or Turkey Oak; we are not aware of any descriptions of this gall or of its occurrence in the UK.]
Photograph the gall on oak, and note the host species
Oak tree
Unknown in England until its appearance in Berkshire in 1997, it is becoming more common and extending its range.
fairly common
See British Plant Galls (Redfern & Shirley, 2023)
Graham Calow
Sapcote, Donkey Lane
29 June 2024
galls on oak
Mike Higgott
Anstey, Link Road Playing Fields
05 July 2024
Dylan
Melton River Eye
19 June 2024
Peter Smith
Leicester, former Western Park Golf Course
17 August 2024
(with marble gall)
Leicestershire & Rutland Map
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UK Map
Species profile
- Common names
- Ramshorn Gall Causer
- Species group:
- Bees, Wasps, Ants
- Kingdom:
- Order:
- Family:
- Records on NatureSpot:
- 95
- First record:
- 01/07/2009 (Calow, Graham)
- Last record:
- 06/11/2025 (Pochin, Christine)
Total records by month
% of records within its species group
10km squares with records
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