Fergusonina Explained

Fergusonina, the sole genus in the family of Fergusoninidae, are gall-forming flies. There are about 40 species in the genus, all of them producing galls on Eucalyptus, Melaleuca, Corymbia, and Metrosideros^[1] species (all in the family Myrtaceae) in Australia and New Zealand.

These flies are small and their larvae grow within galls formed on the leaf, shoot or flower buds. The galls themselves are induced by endosymbiotic nematodes in the genus Fergusobia (family Neotylenchidae) which are obligate mutualists of the flies.^[2] Females carry the nematode in their haemocoel, and transport them to host plants while laying their eggs. Most of the fly species are specific to their tree hosts but a few use more than one species of host.^{[3] [4]}

The taxonomic placement of Fergusoninidae is disputed. While formerly in the superfamily Opomyzoidea, a 2020 study places it within superfamily Nerioidea based on morphology,^[5] while a 2021 study using transcriptome data places it in a group along with Agromyzidae and other families^[6]

Further reading

• Purcell, Michaela Fay Elizabeth. 2017. Phylogeny and host relationships of the Australian gall-inducing fly Fergusonina Malloch (Diptera: Fergusoninidae). Australian National University. PhD thesis.
• Head, Elise. 2008. Ecology of the Fergusonina fly and Fergusobia nematode gall association in South Australia. University of Adelaide. MSc thesis.

Notes and References

1. 10.1111/j.1365-3113.2007.00383.x. First record of Fergusonina (Diptera: Fergusoninidae) and associated Fergusobia (Tylenchida: Neotylenchidae) forming galls on Metrosideros (Myrtaceae) from New Zealand. Systematic Entomology. 32. 3. 548–557. 2007. Taylor. Gary. Davies. Kerrie. Martin. Nicholas. Crosby. Trevor. 84323543.
2. 10.1111/bij.12237. An emerging example of tritrophic coevolution between flies (Diptera: Fergusoninidae) and nematodes (Nematoda: Neotylenchidae) on Myrtaceae host plants. Biological Journal of the Linnean Society. 111. 4. 699–718. 2014. Nelson. Leigh A.. Davies. Kerrie A.. Scheffer. Sonja J.. Taylor. Gary S.. Purcell. Matthew F.. Giblin-Davis. Robin M.. Thornhill. Andrew H.. Yeates. David K.. free.
3. 10.1071/IS02033. Revision of Fergusonina Malloch gall flies (Diptera : Fergusoninidae) from Melaleuca (Myrtaceae). Invertebrate Systematics. 18. 3. 251. 2004. Taylor. Gary S..
4. 10.1016/j.ympev.2017.07.023. 28757445. Phylogenetics of Australasian gall flies (Diptera: Fergusoninidae): Evolutionary patterns of host-shifting and gall morphology. Molecular Phylogenetics and Evolution. 115. 140–160. 2017. Scheffer. S.J.. Davies. K.A.. Taylor. G.S.. Thornhill. A.H.. Lewis. M.L.. Winkler. I.S.. Yeates. D.K.. Purcell. M.F.. Makinson. J.. Giblin-Davis. R.M.. free.
5. Lonsdale . Owen . 2020-02-17 . Family groups of Diopsoidea and Nerioidea (Diptera: Schizophora)—Definition, history and relationships . Zootaxa . 4735 . 1 . 1–177 . 10.11646/zootaxa.4735.1.1 . 1175-5334. free .
6. Bayless . Keith M. . Trautwein . Michelle D. . Meusemann . Karen . Shin . Seunggwan . Petersen . Malte . Donath . Alexander . Podsiadlowski . Lars . Mayer . Christoph . Niehuis . Oliver . Peters . Ralph S. . Meier . Rudolf . 2021-02-08 . Beyond Drosophila: resolving the rapid radiation of schizophoran flies with phylotranscriptomics . BMC Biology . 19 . 1 . 23 . 10.1186/s12915-020-00944-8 . 1741-7007 . 7871583 . 33557827 . free .