Tetraneura ulmi, the elm sack gall aphid and also known as a fig gall, is a species of aphid in the family Aphididae. It was described by Carl Linnaeus and named in his Systema Naturae, published in 1758. The mite is found in Asia, Europe and North America, causing abnormal plant growths, known as galls on their primary host, elm trees (Ulmus species).[2][3][4][5] They feed on a secondary host, the roots of various grasses.
| Tetraneura ulmi | |
|---|---|
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| Gall on an elm leaf | |
Scientific classification 
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Insecta |
| Order: | Hemiptera |
| Suborder: | Sternorrhyncha |
| Family: | Aphididae |
| Subfamily: | Eriosomatinae |
| Genus: | Tetraneura |
| Species: | T. ulmi
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| Binomial name | |
| Tetraneura ulmi | |
| Synonyms | |
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Description
editThe gall is a stalked, club-like smooth pouch (7−15 mm high) on the leaves of elm trees. Feeding inside the gall is a nymph and some wax. Partly formed galls are pale yellow patches with irregular lumpy projections on the top surface of the leaf. On the underside of the leaf, young galls may have a hairy opening.[6]
Life cycle
editMature asexual females leave the galls in the summer and lay eggs on grass roots. The aphids are pink, orange or purple, 2–3 mm long and covered in a thin layer of powdered wax.[7] In the autumn, winged forms fly to elms and give birth to wingless mites of both sexes. After mating each female lays an egg and a female nymph hatches in the spring and starts feeding on the underside of a leaf. The leaf reacts by forming a tiny, yellowish pimple on the upper side, which is the early growth of a gall, into which the nymph enters, feeds and produce offspring.[8]
Galls have been found on the following species, small-leaved elm (Ulmus minor) and wych elm (Ulmus glabra); rarely on American elm (Ulmus americana), David elm (Ulmus davidiana), European white elm (Ulmus laevis).[7]
References
edit- ^ "Tetraneura (Tetraneura) ulmi (Linnaeus, 1758)". Fauna Europaea. Retrieved 16 March 2022.
- ^ "Tetraneura ulmi species details". Catalogue of Life. Retrieved 2018-04-11.
- ^ "Tetraneura ulmi". GBIF. Retrieved 2018-04-11.
- ^ "Tetraneura ulmi Species Information". BugGuide.net. Retrieved 2018-04-11.
- ^ "Tetraneura ulmi Overview". Encyclopedia of Life. Retrieved 2018-04-11.
- ^ Redfern, Margaret; Shirley, Peter; Bloxham, Michael (2011). British Plant Galls (Second ed.). Field Studies Council. p. 340. ISBN 978-1-85153-284-1.
- ^ a b Ellis, W N. "Tetraneura ulmi (Linnaeus, 1758) elm-grass aphid, elm sack gall aphid". Plant Parasites of Europe. Retrieved 16 March 2022.
- ^ Chinery, Michael (2011). Britain's Plant Galls. A photographic guide. Old Basing, Hampshire: WildGuides. p. 42. ISBN 978-1903657-43-0.
Further reading
edit- Arnett, Ross H. Jr. (2000). American Insects: A Handbook of the Insects of America North of Mexico (2nd ed.). CRC Press. ISBN 0-8493-0212-9.
- Foottit, R.G.; Halbert, S.E.; Miller, G.L.; Maw, E.; et al. (2006). "Adventive aphids (Hemiptera: Aphididae) of America north of Mexico". Proc. Ent. Soc. Wash. 108: 583–610.
- Skvarla, Michael J.; Halbert, Susan E.; Foottit, Robert G.; Jensen, Andrew S.; et al. (2017). "An Update to the Adventive Aphids (Hemiptera: Aphidoidea) of America North of Mexico, with Notes on Intercepted Species". Proceedings of the Entomological Society of Washington. 119: 90–111. doi:10.4289/0013-8797.119.1.90. S2CID 91004743.