The so-called “brown cruisers” are no more. On April 16, 2025 genus Didymops, representing two species – the Stream Cruiser (Didymops transversa) and Florida Cruiser (Didymops foridensis) – was changed to Macromia, which includes all of the river cruisers.
Regarding differences between the two genera, Ed Lam’s fantastic new field guide Dragonflies of North America notes that the brown cruisers “fly early in the spring, their life cycle largely completed before river cruisers emerge”. Dennis Paulson’s information-packed guide Dragonflies and Damselflies of the East describes brown cruisers as “smaller, duller editions of the large and showy river cruisers” and states that they “hold the abdomen more elevated than river cruisers do”.
Clearly such differences are no longer important enough to warrant the brown cruisers being placed in their own genus.
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