Taxonomy, Week 6 7 March 2005
Order Esociformes (Pikes, mudminnows)
Family Esocidae (pikes)
Found in lakes & slow rivers, in shallow water
Elongate body (sagittiform), long snout/jaws, with sharp teeth (piscivorous)
Dorsal & anal fins situated far back on body, near caudal region.
Highly prized sportfish; also commercial fishery in Eurasia
Esox masquinongy can reach several feet in length, 40-60 lbs.
Redfin pickerel, Esox americanus americanus
Chain pickerel, Esox niger
Northern pike, Esox lucius
Muskellunge, Esox masquinongy
Family Umbridae (Mudminnows)
Small – less than 15 cm long; freshwater
Prefer slow water – bogs, slow streams, feed on invertebrates (plankton & insects)
Hide in mud when disturbed – can tolerate dry periods by burrowing in sediments
Disjunct distribution - 1 genus, Umbra, with 4 species worldwide – central Europe, central N. America, Atlantic coast of N. America, and Olympic Peninsula in the state of Washington.
IN VERMONT: Central mudminnow, Umbra limi
Marine, freshwater, & anadromous species – distributed worldwide
No nuptial tubercles, most have adipose fin
Some species can estivate in droughts, others emit odor similar to cucumbers!
Generally silvery in color; some deep-sea species are bioluminescent
Southern grayling – Australia region (Not a salmonid grayling) – only right gonad is present
Popular food fish, spawn in sand or gravel in large numbers (good for dip netting)
Ayu – Japanese “sweetfish” – captured using cormorants tethered to a boat
IN VERMONT: Osmerus mordax, Rainbow smelt
1 extant family – Salmonidae (trouts, salmons, chars, whitefishes, graylings)
Soft rayed, physostomus, swim bladder, adipose fin
Many species are sport fishes; widely stocked worldwide for sport fishing
Freshwater, landlocked, or anadromous
Endemic to entire northern hemisphere; many have been transplanted in southern hemisphere
Most Pacific salmon are reknowned for their homing abilities – highly selective to their natal tributary when returning from the ocean to spawn.
Cretaceous period – 144 MYA, probably basal group for higher fishes