Uncovering the species diversity of subterranean rodents at the end of the World: three new species of Patagonian tuco-tucos (Rodentia, Hystricomorpha,Ctenomys)

Abstract

Ctenomys Blainville 1826 is one of the most diverse genera of South American caviomorph rodents. Currently, six species of this genus are reported from Patagonia, south of 42°S. In this contribution, we assessed the taxonomic status of several populations from eastern and central Chubut province, northern Patagonia. Based on phylogenetic analyses of DNA sequences, morphology assessment (qualitative and quantitative), and previously published karyological data, we describe three new species of this genus, one formed by two subspecies, endemic to northern Patagonia. In addition, we include C. coyhaiquensis Kelt and Gallardo 1994 into the synonymy of C. sericeus J.A. Allen 1903. Finally, we discussed the need for additional integrative approaches, including field collection of specimens, to better understand the diversity of this highly speciose rodent genus.

Genomic Organization of Microsatellites and LINE-1-like Retrotransposons: Evolutionary Implications for Ctenomys minutus (Rodentia: Ctenomyidae) Cytotypes

“…Notably, the subterranean rodents of the Neotropical genus Ctenomys (Rodentia: Ctenomyidae) represent an exception to this general rule. This genus comprises approximately 65 species, showing the greatest chromosomal variation among mammals [ 26 ]. In fact, the 2n values varies from 10 in C. steinbachi to 70 in C. pearsoni [ 27 , 28 ].…”

Redefining the Distributional Boundaries and Phylogenetic Relationships for Ctenomids From Central Argentina

“…Subterranean rodents of the genus Ctenomys (Ctenomyidae: Caviomorpha; Blainville, 1826) are the most diverse in number of species of all native South American rodents, with about 68 recognized species ( Bidau, 2015 ; Freitas, 2016 ; Teta and D’Elía, 2020 ; D’Elía et al, 2021 ). However, about 85 names have been assigned to biological entities of this genus and many taxa need to be properly delimited both geographically and systematically ( Woods and Kilpatrick, 2005 ; Parada et al, 2011 ; Mapelli et al, 2017 ; Caraballo et al, 2020 ).…”

“…However, about 85 names have been assigned to biological entities of this genus and many taxa need to be properly delimited both geographically and systematically ( Woods and Kilpatrick, 2005 ; Parada et al, 2011 ; Mapelli et al, 2017 ; Caraballo et al, 2020 ). In this context, the alpha taxonomy of Ctenomys has been intensively revised in the last decade, and new potential species are recurrently recognized (e.g., Parada et al, 2011 ; Caraballo and Rossi, 2017 ; Mapelli et al, 2017 ; Teta and D’Elía, 2020 ) and described (e.g., Freitas et al, 2012 ; Gardner et al, 2014 ; Teta et al, 2020 ; De Santi et al, 2021 ). Furthermore, many of the original classifications of species available in the literature have not been consistent with the geographic and taxonomic limits observed from new molecular information (e.g., Mapelli et al, 2017 ; Teta et al, 2020 ).…”

Using Telomeric Length Measurements and Methylation to Understand The Karyotype Diversification of Ctenomys Minutus (A Small Fossorial Mammals)

“…Studies by classical cytogenetics show that rodents display large karyotypic diversity, with diploid numbers ranging from 2n = 10 in Ctenomys steinbachi (Ctenomyidae) 23 to 2n = 102 in Tympanoctomys barrerae (Octodontidae) 24,25 . The genus Ctenomys has about 65 species described 26 with high rates of chromosomal variation that vary from 2n = 10 to 2n = 70 27 perrensis (2n = 50, 54, 56, and 58) [28][29][30][31][32][33] . Populations of C. minutus have autosomal chromosomes characterized by the morphological variation between biarmed (from 14 to 17 pairs) and acrocentric (from 3 to 10 pairs) chromosomes, thus forming different karyotypes 34 .…”