Exoglossum maxillingua (cutlips minnow) is an olive-green medium-sized minnow (average 6 inches) of North America with a distinguishing lower jaw. Isolated from all other minnows by its three-lobed lower jaw with the middle lobe sticking out like a tongue. The range of this species is from the St. Lawrence and Lake Ontario south into Virginia. It is listed as "threatened" in the Canadian province of Ontario, but may never have been common there as this is the most northerly of its range. It is found in running streams and seems to prefer clear, stony pools but not rapids. The distinctive mouth of the cutlips lets it feed on minuscule shellfish which it scrapes from rocks. Although molluscs appear to be its primary food, it also eats insect larvae and diatoms. An interesting feeding behavio