The zebrafish is named for the five uniform, pigmented, horizontal, blue stripes on the side of the body, which are reminiscent of a zebra's stripes, and which extend to the end of the caudal fin.

The main features of the fish, the fins, are bony fin rays and, except the caudal fin, have no direct connection with the spine.

The caudal peduncle is absent and the caudal fin is reduced to a stiff rudder-like structure.

Sexual dimorphism is slight, the male's caudal fin being more pointed.

An additional caudal fin covers the post-anal tail.

alt = Drawing of a shark labeling major anatomical features, including mouth, snout, nostril, eye, spiracle, dorsal fin spine, caudal keel, clasper, labial furrows, gill openings, precaudal pit and fins: first and second dorsal, anal, pectoral, caudal and pelvic

Sharks possess a heterocercal caudal fin in which the dorsal portion is usually noticeably larger than the ventral portion.

By contrast, most bony fish possess a homocercal caudal fin.

Coelacanths (, adaptation of Modern Latin Cœlacanthus " hollow spine ", from Greek κοῖλ-ος koilos " hollow " + ἄκανθ-α akantha " spine ", referring to the hollow caudal fin rays of the first fossil specimen described and named by Louis Agassiz in 1839 ) are members of an order of fish that includes the oldest known living lineage of Sarcopterygii ( lobe-finned fish and tetrapods ).

They possess a three-lobed caudal fin, also called a trilobate fin.

Coelacanths have 8 fins – 2 dorsal fins, 2 pectoral fins, 2 pelvic fins, 1 anal fin, and 1 caudal fin.

The tail is very nearly equally proportioned and is split by a terminal tuft of fin rays that make up the caudal lobe of the tail.

There is also an anal fin, which is also considered spiny, and a caudal fin.

The lobes of the caudal ( tail ) fin in muskellunge come to a sharper point, while those of northern pike are more generally rounded.

Walleyes are distinguished from their close cousin the sauger by the white colouration on the lower lobe of the caudal fin which is absent on the sauger.

In addition, the two dorsals and the caudal fin of the sauger are marked with distinctive rows of black dots which are absent from or indistinct on the same fins of walleyes.

Drums are somberly colored, usually in shades of brown, with a lateral line that extends to the tip of the caudal fin.

Most species have a rounded or pointed caudal fin.

The caudal fin is strongly divided and rigid, with a slender, ridged, base.

It moves by combining pectoral, dorsal, anal, and caudal fins.

Because of this, they are slow-moving and rely on their pectoral, dorsal, anal, and caudal fins for propulsion rather than by body undulation.

* Rounded caudal fin and pectoral fins, short but high anal fins.

* The dorsal fin originates at the anterior of the caudal end of the operculum, the soft portion of the dorsal fin is more tall than long, the caudal fin is rounded and in adults it is an elongated upper ray, the anal fin originates below the soft portion of the dorsal fin, which it resembles in its rounded shape and being more tall than long.

Their caudal fins and anal fins are sharply concave.

Modern lungfish all have an elongate body with fleshy, paired pectoral and pelvic fins and a single unpaired caudal fin replacing the dorsal, caudal and anal fins of most fishes.

Its dorsal and anal fins confluent with the rudimentary caudal fin.

They have long dorsal fins, and an anal fin that is typically united with the caudal fin.

Their caudal fins are very small, and except for Guentherus it is merged with the long anal fin ( which has 70 fin rays or more ).

As the common name suggests, they are somewhat eel-like in appearance, with elongated bodies and the dorsal and anal fins continuous with the caudal fin.

The dorsal, anal and caudal fins are large, extending for most of the length of the body.

The dorsal and anal fins are usually separate from the caudal fin.

Swamp eels are almost entirely finless ; the pectoral and pelvic fins are absent, the dorsal and anal fins are vestigial, reduced to rayless ridges, and the caudal fin ranges from small to absent, depending on species.

Neither the dorsal nor anal fins have spines, and in Nagaichthys and Pillaia they have fused with the caudal fin ; in the other genera the caudal is small but separate.

In some fish such as tuna or sauries, they are rayless, non-retractable, and found between the last dorsal and / or anal fin and the caudal fin.

This fish has relatively large scales, a long body, and a tapered tail, with the dorsal and anal fins extending all the way to the small caudal fin, with which they are nearly fused.

Like all Scleropages, Asian arowanas have long bodies ; large, elongate pectoral fins ; dorsal and anal fins located far back on the body ; and a much larger caudal fin than that of their South American relative, the silver arowana, Osteoglossum bicirrhosum.

Although the scales are golden, the anal and caudal fins are reddish-brown. Mature red-tailed golden arowanas have brilliant metallic gold lateral scales, gill covers, bellies, and pectoral and pelvic fin membranes, although the back is dark.

* Compared to a tautog or cunner, its mouth is much larger, also the caudal fin, pectoral fin, and soft portion ( 11 rays ) of dorsal fin as long as spiny portion.

* The adipose fin is a soft, fleshy fin found on the back behind the dorsal fin and just forward of the caudal fin.

The single dorsal and ventral fins have spines and soft rays ; the paired pectoral and pelvic fins have soft rays only ; and the caudal fin has soft rays and is truncate and rounded.

They use notched caudal fins, soft dorsal fins, body undulations, and pectoral fins to move forward.

The body is brown with up to 12 narrow dark brown crossbars, the caudal fin is dark brown, and the soft dorsal, anal and pectoral fins are pale.

The pectoral fins contain 15-18 soft rays each ; the pelvic fins are thoracic and contain one spine and six soft rays ; the caudal fin is forked.

All fins are spinous ( excluding the low-slung pectoral fins ) and rounded: there is a single dorsal fin with 3 – 8 spines and 10 – 19 soft rays ; the pelvic fins are thoracic with one spine and 6 – 7 soft rays ; the anal fin has 2 – 3 spines and 8 – 12 soft rays ; and even the forked caudal fin possesses 4 – 7 procurrent spines on each lobe.

The caudal fin, soft dorsal fin and anal fin are rounded.

They have a forked caudal (" tail ") fin and angular anal and soft dorsal fins.

The caudal fin, soft dorsal fin and anal fin are rounded.

Males develop spectacular spawning colours in summer, namely a more metallic-bronze body colour with a red stripe through the caudal ( tail ), anal and spiny and soft dorsal fins.