An extremely successful Triassic-to-
Cretaceous genus of ray-finned fish, the
Lepidotes group was related to the modern
gars. Around a hundred species have been
listed from Mesozoic sediments laid down
around the world, although some badly
preserved specimens have probably been
mistakenly identified as entirely new species.
Different forms of Lepidotes have been
found in a wide variety of environments,
including rivers, lakes and shallow coastal
sea areas. The various species range in
length from 30cm/12in up to 2m/6~ft or
more. The jaws had developed a new
mechanism for shaping themselves
into a tube that could suck in prey
from a distance, and its '
f1atenned or peg-like teeth
were capable of crushing
molluscan prey. Some of
the recognizably thick scales
of Lepidotes have been
found in the fossilized chest
region of the large dinosaur
Baryonyx; the fish-eater
perhaps scooped them up
with its large claws, like a bear.
. Below: Lepidotes scales were about thumbnail-sized,
rhomboid or diamond-shaped and arranged in
rows. Each scale was composed of layers of bone,
dentine and enamel (as in our own teeth). The
enamel often gives its fossils the shiny, jet-black
appearance as seen here. These scales were
probably from the side, or flank, of the body.
Rhomboid
(diamond or
kite) shape
Dorsal scales
Preserved
black
10.
An extremely successful Triassic-to- Cretaceous genus of ray-finned fish, the Lepidotes group was related to the modern gars. Around a hundred species have been listed from Mesozoic sediments laid down around the world, although some badly preserved specimens have probably been mistakenly identified as entirely new species. Different forms of Lepidotes have been found in a wide variety of environments, including rivers, lakes and shallow coastal sea areas. The various species range in length from 30cm/12in up to 2m/6~ft or more. The jaws had developed a new mechanism for shaping themselves into a tube that could suck in prey from a distance, and its ' f1atenned or peg-like teeth were capable of crushing molluscan prey. Some of the recognizably thick scales of Lepidotes have been found in the fossilized chest region of the large dinosaur Baryonyx; the fish-eater perhaps scooped them up with its large claws, like a bear. . Below: Lepidotes scales were about thumbnail-sized, rhomboid or diamond-shaped and arranged in rows. Each scale was composed of layers of bone, dentine and enamel (as in our own teeth). The enamel often gives its fossils the shiny, jet-black appearance as seen here. These scales were probably from the side, or flank, of the body. Rhomboid (diamond or kite) shape Dorsal scales Preserved black 10.
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