Biology
Antistrophus minor induces inconspicuous, externally imperceptible galls in stems of Silphium laciniatum (Fig. 7H) (Tooker et al. 2004; Nastasi and Deans 2021). Weld (1926) reported A. minor from Silphium terebinthinaceum, but Weld’s specimens from this host plant truly represent Antistrophus meganae.

Distribution
Antistrophus minor was described from adults reared alongside A. rufus in Illinois. We examined specimens providing new state records from Iowa and Wisconsin. Known and potential distribution are summarized in Fig. 9. It appears that A. minor is likely sympatric with A. rufus throughout the distribution of S. laciniatum, although further rearing of Silphium species will be needed to better understand the role of geography in the distribution of Antistrophus, especially regarding these two species.

[see also entries on gallformers page for Antistrophus rufus]

- Louis F. Nastasi, John F. Tooker, Charles K. Davis, Cecil N. Smith, Timothy S. Frey, M. J. Hatfield, Tara M. Presnall, Heather M. Hines, Andrew R. Deans: (2024) Cryptic or underworked? Taxonomic revision of the Antistrophus rufus species complex (Cynipoidea, Aulacideini)^©