tloh2's Identifications

L2 Dytiscus sp. larva, caught in a bottle trap inspired by Inoda and Ladion's (2016) "New box trap for large predaceous diving beetles" baited with pig liver and placed in a clearing of sedges & Typha in a beaver pond.

All I can say is for certain is that they are not a D. hatchi larva. They do, however seem to be a caddisfly specialist such as D. harrisii based on morphological features such as a relatively small head and shorter mandibles as described by Leclair et al. in "Prey Choice in Larval Dytiscus harrisii Kirby and D. verticalis Say" (1986), and on account of behaviour and ability to predate caddisfly larvae as viewed in a captive setting.