Grinnell are an ancient fish that swam in the same water dinosaurs stomped through. They have a long, wavy, soft dorsal fin down their back that moves with a snake like rhythm. From their nostrils come two soft tentacles, used in detecting scent.Click to see full answer. In this regard, what is a Grenal?Despite many names, this is a highly distinctive fish. Grinnell are an ancient fish that swam in the same water dinosaurs stomped through. They have a long, wavy, soft dorsal fin down their back that moves with a snake like rhythm. The tail is rounded and well suited for propelling the fish after its favorite prey.Also Know, what type of fish is a Bowfin? Bowfin. Bowfin (Amia calva) are bony fishes related to gars in the infraclass Holostei. Common names include mudfish, mud pike, dogfish, griddle, grinnel, swamp trout and choupique. In respect to this, is a Bowfin fish good to eat? Bowfin are usually not considered a good food fish compared to more popular freshwater gamefish species, such as pike or trout. They are generally regarded as trash fish by sportsmen in the United States, because they eat more desirable species, including crayfish. This is the only surviving member of the Amiidae.What is a Grindle fish?n primitive long-bodied carnivorous freshwater fish with a very long dorsal fin; found in sluggish waters of North America. Synonyms: Amia calva, bowfin, dogfish Type of: ganoid, ganoid fish. primitive fishes having thick bony scales with a shiny covering.