Sharks The Animal Answer Guide

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58 Sharks: The Animal Answer Guide


but a few benthic (bottom-dwelling) families could be considered excep-
tions. Heterodontiform bullhead sharks, especially the juveniles, sport bold
markings. Members of the genus Heterodontus, such as the Zebra Bullhead
Shark (Heterodontus zebra—not to be confused with the even more striking
stegostomatid Zebra Shark, Stegostoma fasciatum), have vertical bars, wavy
lines, and numerous white or black spots. The skin coloration of orectolo-
bid wobbegongs could serve as models for Realtree camouflage patterns.
Wobbegongs sit motionless on algae-covered reef surfaces, and their color
and head frills easily blend into those complex backgrounds. The hemi-
scylliid carpetsharks and bamboosharks are among the most colorful of all
sharks, although their spots, blotches, and bars are still brown, black, or
grey, though often set off with white edges. The tropical Pacific Epaulette
Shark has a beige to brown back covered by brown spots and some darker
bands. It gets its name from a very large black spot that is ringed by white
on each “shoulder,” behind the pectoral fins. (Epaulettes are shoulder bars
on a soldier’s uniform—and the red shoulder patches of Redwing Black-
birds.) The conspicuous ringed epaulette may draw a predator’s attention
away from vulnerable body parts, or it might be mistaken for a large eye
that belongs to a much larger organism, one that shouldn’t be messed with.
We don’t really know.
Also within the Galeomorphi is the strikingly marked Zebra Shark, ju-
veniles of which are popular aquarium animals because of their pattern of
brownish-black rings on a white background. These sharks outgrow even
the largest home tank, becoming leopard-spotted adults 2.5 m (8 ft) long.
Scyliorhinid catsharks can be split into two major groups as far as color is
concerned. Many are uniformly colored deepwater animals (living at about
1,000 m, or 3,300 feet). The shallow-water catsharks are another matter
altogether, with common names that reflect their coloration (Australian
Marbled Catshark, Orange Spotted Catshark, Redspotted Catshark, Tiger
Catshark, Pajama Shark). Many have multiple dark circles lined in white
running the length of their body. Again, these are almost entirely bottom-
sitters.
Other galeomorphs with variable coloration or shading are the Harle-
quin Catshark (Ctenacis fehlmanni), with orange-brown blotches and spots;
the aptly named Leopard Shark of California kelpbeds; and the puzzling
Atlantic Weasel Shark (Paragaelus pectoralis), which has a series of striking
yellow bands running from its snout to its tail. The Atlantic Weasel Shark
may be the only actively swimming shark that can be considered truly col-
orful, and its coloration sets it apart from all the bottom dwellers that are
clearly camouflaged by their color patterns. Longitudinal (lengthwise)
stripes, including yellow stripes, occur in a number of actively swimming
bony fishes with relatively long bodies, such as snappers, rainbow runners,


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