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Genus Pseudogaurax - Parasitic Chloropid Fly

Parasitoids - Pseudogaurax signatus - male - female Pseudogaurax signatus Pseudogaurax (Parasitic Chloropid Fly) - Pseudogaurax anchora Acalyptratae - Pseudogaurax signatus Acalyptratae - Pseudogaurax signatus Pseudogaurax signatus Pseudogaurax signatus? - Pseudogaurax Pseudogaurax
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Diptera (Flies)
No Taxon ("Acalyptratae")
Superfamily Carnoidea
Family Chloropidae (Frit Flies)
Subfamily Oscinellinae
Genus Pseudogaurax (Parasitic Chloropid Fly)
Explanation of Names
Pseudogaurax Malloch 1915
3 spp. in our area, dozens worldwide
hosts: mostly spiders (common in Latrodectus egg sacs), but also egg cases of other arthropods, incl. several insect orders(1)
Life Cycle
Lays eggs in a partially completed spider egg sac. When the sac is finished, the fly larvae hatch and feed on the spider's eggs, but not all of them. The flies need some of the spiderlings alive to dissolve an exit hole in the sac so they can escape. (Smith 1982)
Print References
Barnes J.K., Higgins L.E., Sabrosky C.W. (1992) Life histories of Pseudogaurax species (Diptera: Chloropidae), descriptions of two new species, and ecology of Nephila clavipes (Linnaeus) (Araneae: Tetragnathidae) egg predation. J. Nat. Hist. 26: 823-834 (Full text)
Works Cited
1.Death comes on two wings: a review of dipteran natural enemies of arachnids
Gillung J.P., Borkent C.J. 2017. J. Arachnol. 45: 1–19.