The Common Fish of Ohio by Meaghan Gade and Ben Madden

The Common Fish of Ohio

     In todays episode, we traveled to the laboratory within Dolan Science Center to delve into the identifications of common fish of Ohio. We had a special guest appearance by Dr. Chris Sheil who explained the diversity of fish found within the Ohio waters. Dr. Sheil gave us a lecture on the diagnostic characteristics of common Ohio fish families.

There are many characteristics used to differentiate between the families of these common fish including the types and location of fins, spines, and fin ray features. Additionally, the type of caudal fin, either heterocercal tails, which are tapered at the end and represent the ancestral condition, or homocercal tails in which the upper and lower lobes of the caudal fin are equal can be used as an identifying feature. Also, examining the presence or absence of the lateral line, which allows the fish to sensor the pressure changes in the water, and types of scale types: from ganoid scales which are rhomboid shaped and covered with ganoine, to rounded cycloid scales, and ctenoid scales which are angular or oblong, can help identify families. Once the lecture by Dr. Sheil was finished, we split off and started to go through the many collections of fish set out. We drew an illustration of one representative of each family to help us learn the distinct traits each family express.

Buccal funnel of Lamprey

          The Lampreys belong to the family Petromyzontidae which look eel-like and have no scales, pectoral or pelvic fins. They have multiple gill slits and a buccal funnel with cornified teeth and rasping tongue. They do have dorsal and caudal fins present and characterization of species can be determined by the condition of dorsal fin (not divided, notches between dorsal fins)   

Family Anguillidae

Family Anguillidae, the freshwater eels have fused dorsal, anal, and caudal fin with scales so tiny the fish appears scaleless. Unlike the lamprey, the eel also has pectoral fins with opercular opening anterior to the pectoral fin. 

Acipenseridae tubular mouth and 4 barbels 

One of the larger size representations we examined in lab was the Acipenseridae, or sturgeon. The sturgeon have a tubular mouth with four barbels under snout. There are also large rows of bony plates covering the body. Additionally, sturgeon have a conspicuous heterocercal tail that may contain bony plates on it. 

Family Lepisosteidae, or gar, are found in slow moving waters or side bends and tend to be surface hangers. Gar have ganoid scales that cover the whole body. On the posterior end of the gar, you will find a abbreviated heterocercal tail with a posterior displaced dorsal fin. On the anterior end, the nostrils are at the tip of the snout. Gar have large, fang-like teeth.  


Alosa pseudohareuyus, alewife

Family Lepisosteidae 



Family Clupeidae are the Herrings and can be identified by four significant traits. (1) dorsal fin located over the pelvic fin. (2) keeled belly scales which meet with the long anal fin, giving the belly a “serrated” feel (3) rounded snout and terminal mouth 4. no lateral line system. The alewife, Alosa pseudohareuyus, has an diagnostic eye feature, in which the lids are vertical and the pupil is horizontal.

Adipose fin of Salmonidae

Within the family Salmonidae are salmons, trout, and whitefish. There are two distinct features that can be used to identify this family. (1) the presence of a pelvic axillary process located by the pelvic fin. (2) An adipose fin located dorsally between the dorsal and caudal fin. Also, members of this family have many tiny, cycloid scales. 

Pike are found in the Family Esocidae and are found in large lakes or some small streams. They have huge canine teeth on the duckbill looking snout. The deeply forked caudal fin and posteriorly placed dorsal fin help it cruise along the surface for long distances.  



Family Esocidae



Family Catastomidae consists of suckers, redhorses, and buffalo fish which are identified by their c-shaped, sucker-like lips that are striate. The anal fin is displaced posteriorly and the dorsal fin has up to 9 fin rays. Sometimes, the buffalo fish in this family is confused with carps in family Cyprinidae, however the buffalo fish has a nipple like process on its lower lip, and a conspicuous dorsal fin.

Family Ictaluridae

The Catfish and the madtoms are grouped in the family Ictaluridae. They are identified by the 8 barbells around the mouth. Additionally, the dorsal and pectoral fin have a large spine associated with it along with and they also have an adipose fin, like the Salmonids. To differentiate between madtoms and catfish, the caudal fin is examined. If an unforked fin is present, it is the madtom Notorus. The catfish has a forked caudal fin. 

Family Cyprinidae

The Family Cyprinidae includes carps, minnows, daces, shiners and goldfish. Carp (Cyprinus carpio) has an upperjaw with fleshy barbels. If it does not have barbels on upper jaw, it is Carassius auratus, or the goldfish. The dorsal fin has one stout spine at the leading edge, and is doubly serrated posteriorly. 

Family Atherinidae

The silversides are the Family Atherinidae. They have conspicuous cycloid scales and a very flattened head and back, and typically large eyes. Members of this family have two dorsal fins with the first one containing six spines. 

Family Moronidae

The whitebasses are in the Family Moronidae and have double dorsal fins, the first with spines and the second is without. They also have a small spine on opercle flap. 

The Family Centrarchidae includes the blackbass, crappies, and sunfish. These are classified having a fused dorsal fins and number of anal and dorsal spines. To identify species, scale size can be examined: black bass typically have small scales, while sunfish and crappie usually have large scales. 

Family Centrarchidae

Family Percidae consists of the Walleye, Perch, and Darters. They are identified by having conspicuous paired dorsal fins, a body depth that is less than head length, a torpedo shaped body, and can be classified further into the family by the size of the pectoral fin and facial features (narrow, tapered, blunt). Sometimes, members of this family can be confused with Moronidae, however, the Percidae lack an opercular spine. 

Family Percidae

Family Gobiidae, or the Gobies are identified by having a cup-shaped suction cup as a pelvic fin, and “chubby cheeks”. Additionally, it has a prominent rounded caudal fin. It can often get confused with Etheostoma from family Percidae, however, Etheostoma has a much larger pectoral fin then gobies.

Pelvic fin of Family Gobiidae