Adult females of Tomostethus nigritus on Fraxinus angustifolia, resting on younger leaves (left); sunning on tree stems (right), Ghent (BE), 11.IV.2019 Fons Verheyde.
Part of: Verheyde F, Sioen G (2019) Outbreaks of Tomostethus nigritus (Fabricius, 1804) (Hymenoptera, Tenthredinidae) on Fraxinus angustifolia ‘Raywood’ in Belgium. Journal of Hymenoptera Research 72: 67-81. https://doi.org/10.3897/jhr.72.38284