Fish Review

Family Characteristics

It is important that you first learn to identify the family to which a fish belongs. If you know your family characters you can often recognize the family to which an unknown species belongs -- ands that is often more than half the work of correctly identifying it.

FAMILY CHARACTERISTICS ILLUSTRATION
Lepisosteidae

Pelvic fins abdominal, no spines in fins

Elongated body covered with heavy ganoid scales

Large mouth with lots of large pointed teeth

Heterocercal tail

Amiidae

Pelvic fins abdominal, no spines in fins

Elongated dorsal fin

Modified heterocercal tail (appears almost homocercal from the outside!)

Engraulidae

Pelvic fins abdominal, no spines in fins

Mouth very large, jaw extending to behind eye

Cyprinidae

Pelvic fins abdominal, no spines in fins (introduced Eurasian species such the carp and goldfish possess heavy spine-like first ray in dorsal fin)

Mostly small fishes, often with dark lateral band or spot in front of caudal fin
Mouth variable, but usually small; upper jaw bordered by premaxilla (maxillary excluded from gape); uppser jaw usually protrusible.

Poeciliidae

Pelvic fins abdominal, but pectoral fins placed high on sides
No spines in fins
Anal fin of males modified to form gonopodium
Top of head (supraorbital) with open sensory pits embedded in fleshy grooves.

Atherinidae

Pelvic fins abdominal, but pectoral fins placed high on sides
Spines in fins
Two well separated dorsal fins (the first very small)
Mouth small and terminal
No lateral line
Sides with a broad silvery band (becoming dark in preserved specimens)
Mostly marine, but some species entering or restricted to freshwaters

Mugilidae

Pelvic fins located well forward (subabdominal, almost thoracic), pectorals high on sides
Fins with stiff spines
Two well-separated dorsal fins
Lateral line absent
Scales ctenoid in adults (cycloid in small juveniles)
Mouth moderate, teeth small or absent
Gill rakers long
Stomach modified into a gizzard

Centrarchidae

Pelvic fins thoracic, dorsal and anal fin with spines
Dorsal fin single, continuous or nearly divided by a cleft between spinous anad soft portions
Lateral line present, sometimes incomplete

Percidae

Pelvic fins thoracic, dorsal and anal fin with spines.
Dorsal fins two, divided into separate spinous and soft-rayed portions.

Pomatomidae

Dorsal fins separete, the first very low
Soft dorsal and anal covered with scales
Sides silvery, mouth large, jaws with lots of small, sharp teeth
Monotypic family (only one species worldwide, unless Scombrops also included, in which case there are two species)

Carangidae

Sides typically silvery, sometimes with vertical bars or other markings

Scales very small (almost impossible to see)except for enlarged, spiny scutes which may be present along the sides of the caudal peduncle in some species
Tail forked, lunate in most species.
Anal fin preceded by two free spines (spines may be connected to one another by a membrane in small fish and may become overgrown by skin and flesh in very large ones)

Sciaenidae

Pelvic fins thoracic, dorsal and anal fin with spines.
Dorsal fin single. but with a deep notch dividing spinous and soft-rayed portions.
Caudal fin variously shaped, often with central point (lanceolate) or enlarged lower lobe, but not forked.
Pored scales of lateral line extending to posterior margin of caudal fin.

Achiridae (Soleidae)

Eyes on right side (dextral)
Margin of preopercle covered by skin but still visible (appears as a shallow groove)
Dorsal and anal fins free ffrom caudal
Right pelvic fin joined to anal fin

FAMILY	CHARACTERISTICS	ILLUSTRATION
Lepisosteidae	Pelvic fins abdominal, no spines in fins Elongated body covered with heavy ganoid scales Large mouth with lots of large pointed teeth Heterocercal tail
Amiidae	Pelvic fins abdominal, no spines in fins Elongated dorsal fin Modified heterocercal tail (appears almost homocercal from the outside!)
Engraulidae	Pelvic fins abdominal, no spines in fins Mouth very large, jaw extending to behind eye
Cyprinidae	Pelvic fins abdominal, no spines in fins (introduced Eurasian species such the carp and goldfish possess heavy spine-like first ray in dorsal fin) Mostly small fishes, often with dark lateral band or spot in front of caudal fin Mouth variable, but usually small; upper jaw bordered by premaxilla (maxillary excluded from gape); uppser jaw usually protrusible.
Poeciliidae	Pelvic fins abdominal, but pectoral fins placed high on sides No spines in fins Anal fin of males modified to form gonopodium Top of head (supraorbital) with open sensory pits embedded in fleshy grooves.
Atherinidae	Pelvic fins abdominal, but pectoral fins placed high on sides Spines in fins Two well separated dorsal fins (the first very small) Mouth small and terminal No lateral line Sides with a broad silvery band (becoming dark in preserved specimens) Mostly marine, but some species entering or restricted to freshwaters
Mugilidae	Pelvic fins located well forward (subabdominal, almost thoracic), pectorals high on sides Fins with stiff spines Two well-separated dorsal fins Lateral line absent Scales ctenoid in adults (cycloid in small juveniles) Mouth moderate, teeth small or absent Gill rakers long Stomach modified into a gizzard
Centrarchidae	Pelvic fins thoracic, dorsal and anal fin with spines Dorsal fin single, continuous or nearly divided by a cleft between spinous anad soft portions Lateral line present, sometimes incomplete
Percidae	Pelvic fins thoracic, dorsal and anal fin with spines. Dorsal fins two, divided into separate spinous and soft-rayed portions.
Pomatomidae	Dorsal fins separete, the first very low Soft dorsal and anal covered with scales Sides silvery, mouth large, jaws with lots of small, sharp teeth Monotypic family (only one species worldwide, unless Scombrops also included, in which case there are two species)
Carangidae	Sides typically silvery, sometimes with vertical bars or other markings Scales very small (almost impossible to see)except for enlarged, spiny scutes which may be present along the sides of the caudal peduncle in some species Tail forked, lunate in most species. Anal fin preceded by two free spines (spines may be connected to one another by a membrane in small fish and may become overgrown by skin and flesh in very large ones)
Sciaenidae	Pelvic fins thoracic, dorsal and anal fin with spines. Dorsal fin single. but with a deep notch dividing spinous and soft-rayed portions. Caudal fin variously shaped, often with central point (lanceolate) or enlarged lower lobe, but not forked. Pored scales of lateral line extending to posterior margin of caudal fin.
Achiridae (Soleidae)	Eyes on right side (dextral) Margin of preopercle covered by skin but still visible (appears as a shallow groove) Dorsal and anal fins free ffrom caudal Right pelvic fin joined to anal fin

Comparisons Within Selected Families

Confusion may occur between fishes of the same family, so the following comparisons may be useful.

FAMILY ENGRAULIDAE
Anchovies are abundant schooling fishes found in estuarine and shallow oceanic habitats. Their large mouths and abundant gill-rakers make them well-prepared for a diet of zooplankton. In life they have nearly translucent bodies with a prominent silvery lateral band. In preserved specimens the body becomes opaque and the lateral band almost white. Two species regularly occur in South Carolina inshore waters, additional species may be expected further offshore.

Anchoa hepsetus
The striped anchovy is common in the Atlantic and in higher salinity estuarine habitats. It is best distinguished from the Bay anchovy by its longer, pointed snout and the relative position of the anal fin, the origin of the anal fin occurs near the end of the dorsal fin. In South Carolina it often attains a larger size than the bay anchovy does.

Anchoa mitchelli

The bay anchovy is common in most estuarine habitats as well as occurring in the shallow Atlantic. It has a more rounded snout and the origin of the anal fin occurs under the middle or front of the dorsal fin base. It does not usually attain as large a size as the striped anchovy.

FAMILY CYPRINIDAE

Notropis petersoni
The Coastal shiner, after which, rumor has it, Coastal Carolina University is named, is typically the most abundant small minnow on the Coastal Plain. It has a relatively large mouth (for a minnow), a large eye, and a prominent dark lateral band.

Hybognathus regius

The Eastern silvery minnow is one of the more common minnows on the Coastal Plain. It has a relatively small mouth and eye and the sides are covered with deciduous silvery scales. The opercle typically is bronze colored and a dark lateral band may or may not be evident. The lining of the abdominal cavity (the peritoneum) is dark in this species unlike in most of the shiners which have a light periotoneum. This is often visible in live fish and becomes even more evident in preserved specimens. The species also possesses a coiled intestine (indicative of a herbivorous diet) which may also be visible through the wall of the abdominal cavity in preserved specimens. The dark spots frequently seen on the sides and fins of this as well as other species of minnows are the parasitic larvae of freshwater molluscs.
Some authorities recognize the local variety of Eastern silvery minnow as a distinct species, the Eastern Eastern silvery minnow, H. regius.

Notemigonus crysoleucas
The Golden shiner is among the largest minnows in North America, attaining a length of nearly 1 foot. However, most individuals caught in local streams are much much smaller. The golden shiner possesses a very small, upturned mouth and a very long anal fin (with at least 15 rays, most other minnows have 10 or fewer). Small juveniles possess a dark lateral band which is lost as the fish matures and begins to show the bronze or golden coloration from which it derives its common name.

FAMILY ATHERINIDAE
The silversides, comprise a family of marine and secondary freshwater species all of which look very much alike. The dorsal fin consists of two well-separated parts, the first of which (the spinous dorsal) is often small and not always obvious.

Labidesthes sicculus

The brook silverside is the only atherinid in South Carolina which is regularly found in freshwater. It has an elongated snout which is often dark colored. Breeding fish have bright yellow fins, the color sometimes extending over the entire body.

Historically it has ranged only as far north as the Santee River system drainage, but in the last several years it has been collected in the Little Pee Dee and Waccamaw drainages.

Menidia menidia
The Atlantic silverside is the commonest silverside in most estuarine habitats as well as along the beach and in the shallow Atlantic Ocean. It possesses a long anal fin (23-26 rays) with a straight border.

Membras martinica
The rough silverside occurs in higher salinity marshes and along the beach. Its common name comes from the fact the it has roughened scales, which in larger fish may be detected by running your finger alaong the sides of the fish. The bases of the soft dorsal and anal fins are also covered with rows of scales. Another good character, which works on small as well as large fish, is the that there is a row of large dark spots along either side of the back. Other species of atherinids may possess scattered small spots on the back, but they are not in definite rows. In South Carolina the rough silverside does not usually attain as large a size as the Atlantic silverside.

Menidia beryllinaThe inland silverside occurs in low salinity brackish habitats and has been known elsewhere to occur in freshwater as well. It is distinguished from the similiar Atlantic silverside by having a shorter anal fin (16 -19 rays) with a curved border, the anterior rays being longer than the posterior ones..

FAMILY CENTRARCHIDAE
The family Centrarchidae contains the black basses (Micropterus), crappies (Pomoxis), the flier (Centrarchus) and rock basses (Ambloplites) as well as the sunfishes of the genera Lepomis, Enneacanthus and Acantharchus. Many species are highly regarded as food and game fish, although some species are too small to be widely sought after.

Lepomis auritus
Adult males of the redbreast sunfish possess red or orange chests, but even the smallest fish possess the dark band extending from the back of the eye to the margin of the opercle where it fuses with the opercular spot. They also have a moderate sized mouth (in comparison to other sunfishes) and moderately long, but very stiff gill rakers.

Lepomis macrochirus
Bluegills are distinguished among the sunfishes by having a small mouth, very long pectoral fins, long gill rakers (look under the operculum to see these). Breeding males may be quite colorful, while females and immature fish show a plain banded pattern. The black spot on the soft dorsal is usually present and is the easiest diagnostic character . But beware, in other parts of the country other sunfishes may also have a similiar spot!

Lepomis gibbosus
Pumpkinseed sunfishes get their names (both common and scientific) from the rounded (gibbous) outline of their heads, which gives them a shape rather like a pumpkin seed. This shpae is more common in northern fish than in those found in S.C. which tend to be more elongate and have flatter foreheads, making them harder to identify. Breeding adults usually have colorful wavy lines on their cheeks, but the best characteristic is the isolated red or orange spot on the opercular margin.

Lepomis marginatus
Dollar sunfishes are amoung the smallest sunfishes (they ARE the smallest species osf Lepomis). Breeding fish may be quite colorful, with wavy blue, green and yellow bars on their cheeks, sismiliar to those seen in pumpkinseeds, however all sizes show a white or clear margin around the opercular spot.

Lepomis microlophus
The redear or "shell cracker" is not native to S.C. but has been introduced in farm ponds and lakes and has establishd naturalized populations in the wild. It often hybridizes with native sunfish producing hybrids with intermediate and confusing characteristics. The red margin of the opercular flap gives the species its official common name and is the best diagnostic charcter, but in some cases this color may be restricted, making it appear more like the pumpkinseed. Redears typically have a flatter, sometimes concave, forehead vs. the more rounded (convex) forehead of the pumpkinseed, and also possess longer, pointed pectoral fins, reaching past the eye when they are folded forward. Both species have short gill rakers. As the name "shall cracker" implies, this species feeds primarily on molluscs.

Other Centrarchids
Other sunfishes that occur in S.C. include the warmouth (commonly known as the "morgan" or "more-mouth", L. gulosus a dark brown colored fish with black lines radiating from the eyes. As the local name implies these have a very large mouth, almost as big, relative to the head of the fish, as that of the largemouth bass. Another sunfish is the spotted sunfih or "stump knocker", L. punctatus. These are fairly dark colored fishes, but each scale on the side is marked with an inky-black spot (hence the common name). Both of these two species are common in backwater lakes and swamps.
The Green sunfish, L. cyanellus is not native to the Carolinas but has been introduced into farm ponds and has become established in the Piedmont region of both states. It can be identified by the combination of a large mouth and dark spots on both the soft dorsal and anal fins.
Other centrarchids include the largemouth bass, black and white crappies, and several smaller species such as the flier, mud sunfish and three species of the genus Enneacanthus. These can be distinguished from Lepomis species by a combination of characters including body length, shape of the caudal fin and relative length of the anal fin base.

FAMILY ENGRAULIDAE
Anchovies are abundant schooling fishes found in estuarine and shallow oceanic habitats. Their large mouths and abundant gill-rakers make them well-prepared for a diet of zooplankton. In life they have nearly translucent bodies with a prominent silvery lateral band. In preserved specimens the body becomes opaque and the lateral band almost white. Two species regularly occur in South Carolina inshore waters, additional species may be expected further offshore.
Anchoa hepsetus The striped anchovy is common in the Atlantic and in higher salinity estuarine habitats. It is best distinguished from the Bay anchovy by its longer, pointed snout and the relative position of the anal fin, the origin of the anal fin occurs near the end of the dorsal fin. In South Carolina it often attains a larger size than the bay anchovy does.	Anchoa mitchelli The bay anchovy is common in most estuarine habitats as well as occurring in the shallow Atlantic. It has a more rounded snout and the origin of the anal fin occurs under the middle or front of the dorsal fin base. It does not usually attain as large a size as the striped anchovy.

FAMILY CYPRINIDAE

Notropis petersoni The Coastal shiner, after which, rumor has it, Coastal Carolina University is named, is typically the most abundant small minnow on the Coastal Plain. It has a relatively large mouth (for a minnow), a large eye, and a prominent dark lateral band.	Hybognathus regius The Eastern silvery minnow is one of the more common minnows on the Coastal Plain. It has a relatively small mouth and eye and the sides are covered with deciduous silvery scales. The opercle typically is bronze colored and a dark lateral band may or may not be evident. The lining of the abdominal cavity (the peritoneum) is dark in this species unlike in most of the shiners which have a light periotoneum. This is often visible in live fish and becomes even more evident in preserved specimens. The species also possesses a coiled intestine (indicative of a herbivorous diet) which may also be visible through the wall of the abdominal cavity in preserved specimens. The dark spots frequently seen on the sides and fins of this as well as other species of minnows are the parasitic larvae of freshwater molluscs. Some authorities recognize the local variety of Eastern silvery minnow as a distinct species, the Eastern Eastern silvery minnow, H. regius.
Notemigonus crysoleucas The Golden shiner is among the largest minnows in North America, attaining a length of nearly 1 foot. However, most individuals caught in local streams are much much smaller. The golden shiner possesses a very small, upturned mouth and a very long anal fin (with at least 15 rays, most other minnows have 10 or fewer). Small juveniles possess a dark lateral band which is lost as the fish matures and begins to show the bronze or golden coloration from which it derives its common name.

FAMILY ATHERINIDAE
The silversides, comprise a family of marine and secondary freshwater species all of which look very much alike. The dorsal fin consists of two well-separated parts, the first of which (the spinous dorsal) is often small and not always obvious.
Labidesthes sicculus The brook silverside is the only atherinid in South Carolina which is regularly found in freshwater. It has an elongated snout which is often dark colored. Breeding fish have bright yellow fins, the color sometimes extending over the entire body. Historically it has ranged only as far north as the Santee River system drainage, but in the last several years it has been collected in the Little Pee Dee and Waccamaw drainages.	Menidia menidia The Atlantic silverside is the commonest silverside in most estuarine habitats as well as along the beach and in the shallow Atlantic Ocean. It possesses a long anal fin (23-26 rays) with a straight border.
Membras martinica The rough silverside occurs in higher salinity marshes and along the beach. Its common name comes from the fact the it has roughened scales, which in larger fish may be detected by running your finger alaong the sides of the fish. The bases of the soft dorsal and anal fins are also covered with rows of scales. Another good character, which works on small as well as large fish, is the that there is a row of large dark spots along either side of the back. Other species of atherinids may possess scattered small spots on the back, but they are not in definite rows. In South Carolina the rough silverside does not usually attain as large a size as the Atlantic silverside.	Menidia beryllinaThe inland silverside occurs in low salinity brackish habitats and has been known elsewhere to occur in freshwater as well. It is distinguished from the similiar Atlantic silverside by having a shorter anal fin (16 -19 rays) with a curved border, the anterior rays being longer than the posterior ones..

FAMILY CENTRARCHIDAE
The family Centrarchidae contains the black basses (Micropterus), crappies (Pomoxis), the flier (Centrarchus) and rock basses (Ambloplites) as well as the sunfishes of the genera Lepomis, Enneacanthus and Acantharchus. Many species are highly regarded as food and game fish, although some species are too small to be widely sought after.
Lepomis auritus Adult males of the redbreast sunfish possess red or orange chests, but even the smallest fish possess the dark band extending from the back of the eye to the margin of the opercle where it fuses with the opercular spot. They also have a moderate sized mouth (in comparison to other sunfishes) and moderately long, but very stiff gill rakers.	Lepomis macrochirus Bluegills are distinguished among the sunfishes by having a small mouth, very long pectoral fins, long gill rakers (look under the operculum to see these). Breeding males may be quite colorful, while females and immature fish show a plain banded pattern. The black spot on the soft dorsal is usually present and is the easiest diagnostic character . But beware, in other parts of the country other sunfishes may also have a similiar spot!

Lepomis gibbosus Pumpkinseed sunfishes get their names (both common and scientific) from the rounded (gibbous) outline of their heads, which gives them a shape rather like a pumpkin seed. This shpae is more common in northern fish than in those found in S.C. which tend to be more elongate and have flatter foreheads, making them harder to identify. Breeding adults usually have colorful wavy lines on their cheeks, but the best characteristic is the isolated red or orange spot on the opercular margin.	Lepomis marginatus Dollar sunfishes are amoung the smallest sunfishes (they ARE the smallest species osf Lepomis). Breeding fish may be quite colorful, with wavy blue, green and yellow bars on their cheeks, sismiliar to those seen in pumpkinseeds, however all sizes show a white or clear margin around the opercular spot.

Lepomis microlophus The redear or "shell cracker" is not native to S.C. but has been introduced in farm ponds and lakes and has establishd naturalized populations in the wild. It often hybridizes with native sunfish producing hybrids with intermediate and confusing characteristics. The red margin of the opercular flap gives the species its official common name and is the best diagnostic charcter, but in some cases this color may be restricted, making it appear more like the pumpkinseed. Redears typically have a flatter, sometimes concave, forehead vs. the more rounded (convex) forehead of the pumpkinseed, and also possess longer, pointed pectoral fins, reaching past the eye when they are folded forward. Both species have short gill rakers. As the name "shall cracker" implies, this species feeds primarily on molluscs.	Other Centrarchids Other sunfishes that occur in S.C. include the warmouth (commonly known as the "morgan" or "more-mouth", L. gulosus a dark brown colored fish with black lines radiating from the eyes. As the local name implies these have a very large mouth, almost as big, relative to the head of the fish, as that of the largemouth bass. Another sunfish is the spotted sunfih or "stump knocker", L. punctatus. These are fairly dark colored fishes, but each scale on the side is marked with an inky-black spot (hence the common name). Both of these two species are common in backwater lakes and swamps. The Green sunfish, L. cyanellus is not native to the Carolinas but has been introduced into farm ponds and has become established in the Piedmont region of both states. It can be identified by the combination of a large mouth and dark spots on both the soft dorsal and anal fins. Other centrarchids include the largemouth bass, black and white crappies, and several smaller species such as the flier, mud sunfish and three species of the genus Enneacanthus. These can be distinguished from Lepomis species by a combination of characters including body length, shape of the caudal fin and relative length of the anal fin base.

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