Fishes, Reptiles, and Amphibians
ENV 311/EEB 320 - Rivers, Lakes, and Wetlands

You should be familiar with all organisms in bold. All names with an asterisk (*) represent taxa that you should be able to sight-identify to the indicated level within two (2) minutes.


Phylum Chordata - chordates

Subphylum Vertebrata – vertebrates


Class Agnatha - lampreys and hagfishes


Family Petromyzontidae* – lampreys

ID: Elongated body; lacks fins, scales, and opercula;
Habitat: streams
Notes: Has unique larval stage (ammocoete) lacking fully functional eyes and mouthparts, feed on detritus and drift. Adults may be parasites, predators, or non-feeders. Parasitic kinds use teeth on sucking disc to rasp feeding holes in fish.


Class Osteichthyes – bony fishes (common families only)



Order Lepisosteiformes – gars
Family Lepisosteidae* – gars

ID: Long, thin body with heterocercal tail; gainoid scales are armorlike; long, fixed jaws and sharp teeth
Habitat: Large bodies of water, especially where weedy areas exist
Notes: Can breathe air directly; usually an ambush predator


Order Amiiformes – bowfins
Family Amiidae* – bowfins

ID: Heterocercal tail; long dorsal fin; rounded caudal fin; large, rounded pectoral fins; prominent black spot at base of upper caudal in adult males
Habitat: Backwater pools of rivers, lakes, and swamps; prefer areas of clear water with abundant vegetation
Notes: Can breathe air directly; mobile upper jaw; ambush predator


Order Clupeiformes – herring-like fishes
Family Salmonidae* – trouts, salmons, and ciscoes

ID: Single soft dorsal fin; fleshy adipose fin; small scales; spotted
Habitat: Ground-water streams; deep, oligotrophic lakes
Notes: High oxygen demand; most are predatory, first on invertebrates, then on other fish;



Family Umbridae* – mudminnows

ID: Soft dorsal fin placed far back on body; rounded caudal fin; black stripe on caudal peduncle
Habitat: Wide variety
Notes: Small, hardy fish; can survive under low oxygen conditions; closely related to pikes



Family Esocidae* – pikes

ID: Soft dorsal fin placed far back on body, roughly even with anal fin; caudal fin is slightly forked; snout is duck-billed in appearance;
Habitat: Streams, lakes, and many wetlands
Notes: Voracious ambush predator; feeds primarily on other fish;


Order Cypriniformes – minnows, suckers, catfishes
Family Cyprinidae* – minnows, carps

ID: Simple looking with single soft dorsal fin; mouth ranges from subterminal to upturned; usually without complex patterning, but occasionally colorful; includes shiners, minnows, carps, and goldfish (the latter two are invasive exotics)
Habitat: Wide variety, usually warmer water
Notes: Very large and diverse family; wide variety of feeding strategies, some are filter-feeders, others are predators



Family Catostomidae* – suckers and redhorses

ID: Look like Cyprinids but have ventral mouth that is sucker-like with thick lips
Habitat: Benthic environments
Notes: Sift through sediments for invertebrates and sometimes algae



Family Ictaluridae* – catfishes

ID: Barbels, adipose fin, and single spines in both the pectoral and dorsal fin; no scales
Habitat: Benthic environments, mostly
Notes: Size ranges from tiny to enormous; extra taste buds on body allow them to locate food where light levels are low


Order Perciformes – perches, sunfishes, sculpins
Family Percidae* – perches, darters, and walleyes

ID: Two dorsal fins, one spiny and one soft; anal fin with 1-2 spines; opercular spines;
Habitat: deep lakes, rivers
Notes: Darters are usually small and have lost gas bladder; others are good swimmers, voracious predators, and medium-sized



Family Centrarchidae* – sunfishes and tropical basses

ID: Two dorsal fins, usually connected; anal fin with 3+ spines
Habitat: Lakes, rivers, warmer water
Notes: Includes many sport fishes; small to medium predators of inverts and other fish



Family Cottidae* – sculpin

ID: Two dorsal fins; tend to be dorso-ventrally flattened with large head and dorsal eyes; pre-opercular spines;
Habitat: Cool to cold water;
Notes: Prey mainly on inverts; often associated with, and eaten by, trout



Family Gasterosteidae* – sticklebacks

ID: Spiny "finlets" on first dorsal fin; extremely thin caudal peduncle; no scale
Habitat: Quieter water
Notes: Eat inverts


Class Amphibia - frogs and toads, salamanders and newts, caecilians


Order Anura* - frogs and toads


Order Caudata* - salamanders


Class Reptilia - frogs and toads, salamanders and newts, caecilians


Order Testudines* - turtles


Order Squamata
Suborder Sperpentes

Family Colubridae
water snakes