Identifying the two mirids
N. tenuis was detected for the first time in France in 1986, in the Rhône valley [1]. M. pygmaeus has been used as a beneficial insect to control many tomato pests since the early 1990s [2].
N. tenuis and M. pygmaeus are two predatory plant bugs that belong to the family Miridae, tribe Dicyphini. They have a very similar morphology and feed on some of the same host plants and insect prey. The two bugs can therefore easily be mistaken one for the other. Some morphological characteristics, visible to the naked eye or with a hand lens, make it possible to distinguish one from the other (see photo below). Phytophagous activity can also be used to differentiate the two species. Indeed, in the absence of prey, N. tenuis causes damage that is highly detrimental to the tomato crop, which is not the case for M. pygmaeus. This is why N. tenuis is considered as an important pest of tomato crops, especially in soilless cultivation, in the South of France.