Chromosomal Diversity of Thorny Catfishes (Siluriformes-Doradidae): A Case of Allopatric Speciation Among Wertheimerinae Species of São Francisco and Brazilian Eastern Coastal Drainages

Karyotypic characterization of Centromochlus schultzi Rössel 1962 (Auchenipteridae, Centromochlinae) from the Xingu River basin: New inferences on chromosomal evolution in Centromochlus

“…Considering this recent proposal made for Doradidae ( Takagui et al, 2019 ), two hypotheses can be made regarding the evolution of this character in the Doradoidea superfamily: (1) the 18S/5S rDNA synteny, detected for the first time in Auchenipteridae in C. schultzi , comprises a plesiomorphic state congruent to the proposal of synteny is ancestral in Doradidae; or (2) this synteny in C. schultzi should only be interpreted as an apomorphy of the species or a synapomorphy of some Centromochlinae species. We believe that the second hypothesis is more parsimonious and that the study of additional taxa is required to clarify this issue properly.…”

Karyotype Evolution of Talking Thorny Catfishes Anadoras (Doradidae, Astrodoradinae): A Process Mediated by Structural Rearrangements and Intense Reorganization of Repetitive DNAs

“…Pericentric inversions have been frequently detected in many groups of fish, especially among the Siluriformes where they are considered the major rearrangements in the karyotype diversification in Loricariichthys [Takagui et al, 2014], Rineloricaria [Venturelli et al, 2021], Trachelyopterus [Santos et al, 2021], Tatia [Lui et al, 2013a], Pimelodus [Girardi et al, 2018], and Trichomycterus [Oliveira et al, 2016]. Among Doradidae, multiple pericentric inversions events associated with heterochromatin movements occurred independently in several clades and played a key role in the diversification of Wertheimerinae [Eler et al, 2007;Takagui et al, 2019] and Doradinae subfamilies, especially in the large species allocated in the nonfimbriated barbels clade [Milhomem et al, 2008;Baumgärtner et al, 2018;Takagui et al, 2021] and in the widespread species T. paraguayensis [Baumgärtner et al, 2016].…”

“…However, a major obstacle in using this type of approach is the lack of cytogenetic data for some groups, or when they are available, they are either fragmented or restricted to certain clades. Thus they are poorly representative in relation to the total diversity of a given group, as seen for instance within Doradidae thorny catfishes [Baumgärtner et al, 2018;Takagui et al, 2019]. This family has upwards of 96 valid species [Fricke and Eschmeyer, 2021] widely distributed along South America, where they are popularly known as armaus, abotoados, rique-rique, serrudo, among others.…”

Integrating Genomic and Chromosomal Data: A Cytogenetic Study of Transancistrus santarosensis (Loricariidae: Hypostominae) with Characterization of a ZZ/ZW Sex Chromosome System

“…Only a little amount of cytogenetic information is known for loricariid catfishes; the most thorough collection of karyotypes [ 12 ] revealed information for only 7% of the recognized valid species in this family [ 16 ]. This number has grown as a result of recent research [ 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 ], albeit it is impossible to determine it precisely because the majority of the new information relates to samples that could not be reliably identified at the species level. On the whole cytogenetic data presently available include representatives of 29 genera and only one out of the 50 Loricariidae from Ecuador.…”