Endocranial anatomy and phylogenetic position of the crocodylian Eosuchus lerichei from the late Paleocene of northwestern Europe and potential adaptations for transoceanic dispersal in gavialoids
The Anatomical Record,
Journal Year:
2024,
Volume and Issue:
308(2), P. 636 - 670
Published: Sept. 3, 2024
Abstract
Eosuchus
lerichei
is
a
gavialoid
crocodylian
from
late
Paleocene
marine
deposits
of
northwestern
Europe,
known
skull
and
lower
jaws,
as
well
postcrania.
Its
sister
taxon
relationship
with
the
approximately
contemporaneous
species
minor
east
coast
USA
has
been
explained
through
transoceanic
dispersal,
indicating
capability
for
salt
excretion
that
absent
in
extant
gavialoids.
However,
there
currently
no
anatomical
evidence
to
support
adaptation
extinct
Furthermore,
placement
within
Gavialoidea
labile,
some
analyses
supporting
affinities
Late
Cretaceous
early
Paleogene
“thoracosaurs.”
Here
we
present
novel
data
on
internal
external
anatomy
E.
enables
revised
diagnosis,
6
autapormorphies
identified
genus
10
features
enable
differentiation
.
Our
phylogenetic
recover
an
diverging
gavialid
not
part
“thoracosaur”
group.
In
addition
thickened
semi‐circular
canal
walls
endosseous
labyrinth
paratympanic
sinus
reduction,
identify
potential
osteological
correlates
glands
surface
prefrontal
lacrimal
bones
These
potentially
provide
dispersal
,
also
them
Portugalosuchus
Given
earliest
stratigraphically
oldest
gavialoids
either
have
nasal
gland
and/or
recovered
deposits,
this
suggests
capacity
might
be
ancestral
Gavialoidea.
Mapping
geological
onto
phylogeny
indicates
was
probably
more
than
one
independent
loss/reduction
Language: Английский
A review of the non‐semiaquatic adaptations of extinct crocodylomorphs throughout their fossil record
The Anatomical Record,
Journal Year:
2024,
Volume and Issue:
308(2), P. 266 - 314
Published: Nov. 25, 2024
Abstract
Crocodylomorphs
constitute
a
clade
of
archosaurs
that
have
thrived
since
the
Mesozoic
until
today
and
survived
numerous
major
biological
crises.
Contrary
to
historic
belief,
their
semiaquatic
extant
representatives
(crocodylians)
are
not
living
fossils,
and,
during
evolutionary
history,
crocodylomorphs
evolved
live
in
variety
environments.
This
review
aims
summarize
non‐semiaquatic
adaptations
(i.e.,
either
terrestrial
or
fully
aquatic)
different
groups
from
periods,
highlighting
how
exactly
those
lifestyles
inferred
for
animals,
with
regard
geographic
temporal
distribution
phylogenetic
relationships.
The
ancestral
condition
Crocodylomorpha
seems
been
lifestyle,
linked
several
morphological
such
as
an
altirostral
skull,
long
limbs
allowing
erect
posture
specialized
dentition
diets
based
on
land.
However,
some
members
this
clade,
thalattosuchians
dyrosaurids
display
opposite,
aquatic
interestingly
same
type
observations.
Finally,
new
techniques
inferring
paleobiology
extinct
animals
put
forward
last
decade,
appearing
complementary
approach
traditional
descriptions
comparisons.
Such
is
case
paleoneuroanatomical
(CT
scan
data),
histological,
geochemical
studies.
Language: Английский
The role of climate on the emergence of giant caimanines (Crocodylia, Alligatoroidea) from the Miocene western Amazonian region
Palaeogeography Palaeoclimatology Palaeoecology,
Journal Year:
2024,
Volume and Issue:
656, P. 112582 - 112582
Published: Nov. 3, 2024
Language: Английский
Size, not phylogeny, explains the morphology of the endosseous labyrinth in the crown clade Crocodylia
Journal of Anatomy,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 20, 2024
Abstract
The
endosseous
labyrinths
are
associated
with
several
functions,
including
hearing
and
spatial
orientation.
Throughout
their
evolutionary
history,
crocodylomorphs
have
thrived
in
diverse
environments,
the
morphology
of
has
been
suggested
as
a
proxy
for
inferring
lifestyle.
However,
relationships
between
shape
ontogenetic
phylogenetic
factors
difficult
to
interpret
rarely
investigated
depth
previously,
particularly
terms
dataset
size.
Here,
we
present
most
complete
date
on
extant
crocodylians,
111
specimens
covering
22
species
different
status
(from
hatchlings
adults).
Using
3D
geometric
morphometrics,
show
that
allometry
constitutes
major
contributor
variation
crocodylian
development
this
structure
is
likely
linked
braincase
conformation,
all
genera.
We
also
find
moderate
signal,
but
only
without
considering
size
effect,
so
it
could
not
be
translated
into
relevant
discrete
morphological
characters.
Based
these
results,
discuss
remaining
problems
prevent
inclusion
fossil
forms
highly
divergent
lifestyles
study
how
ecological
differences
shaped
crocodylomorphs.
Language: Английский