Complete mitogenomes of pangasiid catfishes and their phylogeny for
taxonomic implications for Pangasiidae and the suborder Siluroidei
Abstract
Although Pangasiidae (four genera: Pangasius, Pangasianodon,
Helicophagus, and Pseudolais) is known to be a monophyletic family, the
generic and phylogenetic relationships, as well as inter- and
intrafamilial relationships of the catfish families in Siluroidei, are
poorly resolved. In this study, we obtained complete mitogenomes from
three catfish species of the Mekong River in Vietnam: Pangasius
mekongensis (16,462 bp), Pangasius krempfi (16,475 bp), and
Pangasianodon hypophthalmus (16,523 bp) and reconstructed a
comprehensive phylogeny with 117 mitogenomes of 32 recognized siluriform
families. The genomic features of the three mitogenomes were similar to
those of previously reported pangasiids, including all regulatory
elements, extended terminal associated sequences (ETAS), and conserved
sequence blocks (CSBs) (CSB-1, CSB-2, CSB-3, and CSBs, A to F) in the
control region. The phylogeny established Pangasiidae as monophyletic
and a sister group of Austroglanididae. The [Pangasiidae +
Austroglanididae] + (Ictaluridae + Cranoglanididae) + Ariidae] clade
is a sister group to the “Big Africa” major clade of Siluriformes.
Furthermore, both phylogenies constructed from the single barcodes (83
partial cox1 and 80 partial cytB, respectively) clearly resolved the
Pangasiidae’s intrafamilial and intergeneric relationships.
Pangasianodon was monophyletic and conclusively as a sister to the
(Pangasius + Helicophagus + Pseudolais) group. Pangasius. mekongensis
was placed as a sister taxon to P. pangasius within the genus Pangasius,
while Pangasius sanitwongsei was found to be related to and grouped with
Pangasianodon. However, in the single-gene phylogenies, this species was
assigned to the [Pangasius + Helicophagus + Pseudolais] group. The
datasets in this study are useful for reappraising pangasiid taxonomy,
as well as for siluriform catfish identification, DNA barcoding,
systematics, phylogenetics, population genetics, and timeline and mode
of diversification studies.