I know this question is a central issue that keeps most of you up at night, but it was bothering Kelly Tindall, Cory Cross, and myself. We found Languria mozardi tunneling in soybean stems and were curious as to why we found this native insect in a non-native plant. This was especially interesting to us as another stem-boring beetle, Dectes texanus, is also a native beetle that has made a switch from boring native plants in the family Asteraceae to boring stems of non-native plants in the family Fabaceae.
As we read the literature on the plants used by L. mozardi, we found things that just did not seem right. The primary clue was: Languria mozardi was using plants that didn’t exist! We then went back to the source material to try and figure out exactly what was the case for this insect. To make a long story short, by not using consistent criteria and terminology 48 plants were listed as host plants for L. mozardi when only 13 were actual developmental hosts.
So we critically thought about how insects (especially L. mozardi) use plants, then came up with a way of evaluating the source literature, then slugged our way through all the source literature, and finally developed a little paper to report our results: Fothergill, K., K.V. Tindall, and C.B. Cross. 2013. What is a host plant? Plants used by Languria mozardi Latreille 1807 (Coleoptera: Erotylidae): a review. Pan-Pacific Entomologist 89.1:43-59.