The DNA barcode reveals cryptic diversity and a new record for the genus Leporinus (Characiformes, Anostomidae) in the hydrographic basins of central northern Brazil

Abstract

Leporinus is one of the most speciose genera of the order Characiformes, with 81 valid species distributed throughout much of Central and South America. The considerable diversity of this genus has generated extensive debate on its classification and internal arrangement. In the present study, we investigated the species diversity of the genus Leporinus in central northern Brazil, and conclude that six valid species—Leporinus maculatus, Leporinus unitaeniatus, Leporinus affinis, Leporinus venerei, Leporinus cf. friderici, and Leporinus piau—are found in the hydrographic basins of the Brazilian states of Maranhão, Piauí, and Tocantins. We analyzed 182 sequences of the Cytochrome Oxidase subunit I gene, of which, 157 were obtained from Leporinus specimens collected from the basins of the Itapecuru, Mearim, Turiaçu, Pericumã, Periá, Preguiças, Parnaíba, and Tocantins rivers. The species delimitation analyses, based on the ABGD, ASAP, mPTP, bPTP, and GMYC methods, revealed the presence of four distinct molecular operational taxonomic units (MOTUs), identified as L. maculatus, L. unitaeniatus, L. affinis, and L. piau (from the Parnaíba River). The bPTP method restricted L. venerei to a single MOTU, and confirmed the occurrence of this species in the rivers of Maranhão for the first time. The separation of L. cf. friderici into two clades and the subsequent formation of different operational taxonomic units was consistent with polyphyly in this species, which indicates the existence of cryptic diversity. The arrangement of L. cf. friderici and L. piau in two different clades supports the conclusion that the L. piau specimens from Maranhão were misidentified, based on their morphological traits, reflecting the taxonomic inconsistencies that exist among morphologically similar species. Overall, then, the species delimitation methods employed in the present study indicated the presence of six MOTUs—L. maculatus, L. unitaenitus, L. affinis, L. cf. friderici, L. venerei, and L. piau. In the case of two other MOTUs identified in the present study, one (L. venerei) is a new record for the state of Maranhão, and we believe that the other represents a population of L. piau from the basin of the Parnaíba River.

Molecular Evidence Reveals Taxonomic Uncertainties and Cryptic Diversity in the Neotropical Catfish of the Genus Pimelodus (Siluriformes: Pimelodidae)

“…As Ramirez et al [17] point out, scenarios of this type may arise principally when a barcoding analysis focuses on a group of intimately related species, such as those of the same genus. Similar situations have been observed in a number of studies of fish genera, such as Astyanax Baird & Girard 1854 [67], Megaleporinus [16], Laemolyta Cope, 1872 [68], Leporinus Agassiz, 1829 [15,69], Prochilodus Agassiz, 1829 [70], and Brycon Müller & Troschel 1844 [71]. Even so, an integrated approach including multiple traits would be necessary to best determine whether the MOTUs found in the present study actually represent recent speciation or simply a high level of population structuring.…”

Analysis of Whole-Genome as a Novel Strategy for Animal Species Identification

“…The core innovation of this study lies in the identification of species through whole genome analysis, wherein species-specific sequences are extracted from the whole genome, including both nuclear and mitochondrial genomes. The vast majority of studies have used the COI gene to identify animals such as mammals [ 23 ], snakes [ 24 ], fish [ 25 , 26 , 27 ], and insects [ 28 , 29 , 30 , 31 ]. Some studies have also used four additional DNA fragments, cytochrome b (cyt b), 16S rDNA, ITS2, and 12S rDNA for animal identification.…”

“…23,25,26,27,32,33, and CK; II contains 4,5,6,14,15,16,17,24,28,29,30,31,34,and 35; III cont 2,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34 and CK; IV contains 1, 10, and 19; V contains1, 4, 5, 6, 10, 14, 15, 16, 17, 19, 24, 28, 29, 30, 34, 35, …”

Exploring hidden diversity: Molecular insights into the Leporinus species of the rivers of the Brazilian states of Maranhão and Piauí

“…Leporinus friderici (Bloch, 1794) is one of the most amply distributed species of the genus and has been found in the majority of the hydrographic basins of South America . Given its broad distribution, many different studies have investigated the characteristics of this species over the years and have found considerable variation in the morphological and genetic patterns of the different L. friderici populations Géry et al, 1987;Nascimento et al, 2023;Renno et al, 1990;Renno et al, 1991;Sidlauskas & Vari, 2012;Silva-Santos et al, 2018). The sum of this evidence indicates that the L. friderici morphotype does in fact represent a species complex, with only the L. friderici specimens from the rivers of Suriname and French Guiana being recognized as members of the type species (Sidlauskas & Vari, 2012).…”