- discarded. Now, the
ptyctodonts are
regarded as the
sister group of the
Arthrodira and Phyllolepida. Fin
spine of the
ptyctodont, Gamphacanthus, showing...
- placoderms; and, most importantly, that
holocephalians have true teeth,
while ptyctodonts have beak-like
tooth plates.
Ptyctodontids were ****ually dimorphic, with...
- (November 1996). "A New
Ptyctodont (Placodermi) from the
Upper Devonian Martin Formation of
Northern Arizona, and an
Analysis of
Ptyctodont Phylogeny". Journal...
-
ptyctodont, but
places it in his "incertae sedis" section.
Individual specimens tend to
resemble the
ptyctodonts from the same
units and
ptyctodonts from...
-
genus and
species of
Ptyctodont (Placodermi) from the Late
Devonian Gneudna Formation,
Western Australia, and an
analysis of
Ptyctodont phylogeny". Geological...
- edrioasteroids,
dendroid graptolites, conodonts,
arthrodire placoderms,
ptyctodont placoderms,
rhenaniform placoderms,
petalichthyiform placoderms, chondrichthyans...
-
acanthoracids resembled scaly chimaeras and (relatively)
heavily armored ptyctodonts. They were
distinguished from
chimaeras by
their large scales and plates...
- κτείς kteis, 'comb' and Gr****: ουρά ourá, 'tail') is an
extinct genus of
ptyctodont placoderm from the Late
Devonian of Germany. The
first fossils were found...
-
diagram suggests that E.
primordialis forms a
polytomy with arthrodires,
ptyctodonts, and all
advanced gnathostomes (namely bony fish, tetrapods, acanthodians...
-
placoderms that have been
found in Michigan, the antiarchs, arthrodires, and
ptyctodonts.
Arthrodires reported from
Michigan rocks include Dunkleosteus, Holonema...
