- bite in some
gnathostomes.
Newer research suggests that a
branch of
Placoderms was most
likely the
ancestor of present-day
gnathostomes. A 419-million-year-old...
-
cyclostomes and
gnathostomes went
through a
genome duplication before their split, and
while a
second genome duplicatio occurred in the stem-
gnathostomes, the stem-cyclostomes...
-
ancestral to hagfishes, and
finally as the
closest jawless relatives of the
gnathostomes. This last
theory was
based on the fact that they seem to have a paired...
-
closely integrated as in
modern gnathostomes.
These teeth were
likely homologous to the
teeth of
other gnathostomes. One of the
largest known arthrodires...
- †Placodermi (Paleozoic
armoured forms;
paraphyletic in
relation to all
other gnathostomes)
class Chondrichthyes (cartilaginous fish; 900+ species)
class †Acanthodii...
- animals,
cyclostomes are
sister to all
vertebrates with jaws,
known as
gnathostomes.
Molecular data, both from rRNA and from
mtDNA as well as embryological...
- Hypothalamic–pituitary–gonadal axis, a
system which once
thought to be
exclusive to the
Gnathostomes. Some
species of
hagfish reproduce seasonally,
stimulated by hormones...
- the
squamosal (a
small cranial bone) meet to form the joint. In most
gnathostomes,
including early therapsids, the
joint consists of the
articular (a small...
-
Vertebrata └─Infraphylum
Gnathostomata ├─Placodermi —
extinct (armored
gnathostomes) └Eugnathostomata (true
jawed vertebrates) ├─Acanthodii (stem cartilaginous...
-
Acanthodii or
acanthodians is an
extinct class of
gnathostomes (jawed fishes). They are
currently considered to
represent a
paraphyletic grade of various...