A worldwide community photographing and learning about wildlife
Project Noah Nature School
Trichilogaster sp
Multiple reddish green lobed galls on stems of the Sydney Golden Wattle. Pic 3 shows a dried gall. These galls are made by a chalcidoid wasp.
Spotted on Sallow Wattle in a reserve.
My thanks to John La Salle for his comments about the Trichilogaster species of wasps. This is probably T.maideni which forms stem galls on at least two species of Acacia - A.maideni and A.implexa. IThis needs further research.
Spotted on Sep 21, 2013
Submitted on Sep 30, 2013
5 Comments
Thanks Martin and Stephen. I need to research this further, obviously.
Thank you John La Salle for your comments. Prior to this I had only seen galls involving flowers buds, especially on A.pycnantha (Australian Golden wattle) and i read that these were caused by Trichilogaster signiventris. I must read further about T.maideni. Thanks again.
Interesting that these are on stems. A recent paper discusses the taxonomy and biology of the 9 known species of Trichilogaster (G. L. Prinsloo and O. C. Neser, 2007, Revision of the pteromalid wasp genus Trichilogaster Mayr (Hymenoptera: Chalcidoidea): gall-inducers on Australian acacias, African Entomology, 15(1):161-184. 2007).
They mention that T. acaciaelongifoliae is a bud galling species, but do mention that others (e.g. T. maideni) induce bud and stem galls on Acacia.
You can find this paper through Google Scholar.
Great information Leuba. It seems the wasps arrived before the flowers were setting and they attacked the stems.
these things have always fascinated me, nice spotting and info