Mitogenomic Insights of notopterids (Actinopterygii: Osteoglossomorpha) from Sundaland biodiversity hotspot: Transcontinental diversification and colonization before Last Glacial Maximum
Abstract
Notopterid
freshwater
fishes
are
distributed
across
Africa
and
Asia,
but
their
genomic
diversity
evolutionary
history,
particularly
within
the
Sundaland
biodiversity
hotspot,
remain
poorly
understood.
This
study
provides
a
novel
mitochondrial
genome
of
Chitala
borneensis
six
additional
mitogenomes
lopis
Notopterus
notopterus ,
obtained
from
type
localities
three
major
Sundaic
Islands.
A
comprehensive
investigation
involving
structural
analysis,
comparative
genomics,
phylogenetic
reconstruction
was
conducted
to
elucidate
diversity,
relationships,
divergence
patterns.
All
species
displayed
typical
teleost
mitogenomic
architecture,
with
C.
possessing
largest
(16,943
bp).
The
exhibited
an
AT
bias,
most
protein-coding
genes
initiating
translation
ATG
start
codon
showing
evidence
strong
purifying
selection.
analyses
using
Bayesian
Maximum-likelihood
methods
illustrated
two
clades
notopterids
separating
Asian
African
lineages
during
Mesozoic
era.
However,
Chitala
Notopterus
diverged
Cenozoic,
processes
continuing
into
Miocene.
notable
high
mean
genetic
(8.84%)
among
suggested
long-term
isolation,
while
deep
intraspecific
variation
in
N.
notopterus
(4.32%)
indicated
presence
possible
cryptic
Sundaland.
These
findings
support
hypothesis
transcontinental
diversification
this
Old-World
underscore
historical
biogeographic
significance
South
Southeast
Asia.
Specifically,
region
likely
facilitated
gene
flow
common
ancestors
extant
valid
via
interconnected
palaeodrainage
systems
prior
Last
Glacial
Maximum,
connectivity
subsequently
disrupted
by
post-glacial
sea-level
rise.
Research Square (Research Square), Journal Year: 2025, Volume and Issue: unknown
Published: May 6, 2025
Language: Английский