Abstract:
DNA barcoding is a widely utilized molecular-based
identification of species and taxonomic resolutions.
Until recently, Rhamdia voulezi and Rhamdia
branneri were considered species synonyms of
Rhamdia
quelen; however,
morphological and cytogenetic analyses have suggested
the validity of distinct species. Due to the absence
of molecular taxonomy of R. voulezi and R.
branneri, the objective of this study was to
test its validity through traditional DNA barcoding
and the GMYC (General Mixed Yule Coalescent) COI-based
analyses in 19 specimens from the Iguaçu River
Basin. In both methodologies, three MOTUs (Molecular
Operational Taxonomic Units) were identified based
on the estimated optimum threshold (OT = 0.77). The
average inter-MOTU distance (NJ, K2P) between R.
branneri and R. voulezi was 1.4%, and
0% intra-MOTU distance in both species. The two species
identified as R. branneri and R. voulezi
showed correspondence with taxonomic and morphological
identifications. With regard to R. quelen,
the average intra-MOTU distance was greater than OT
(2.7%), indicating that this species can be formed
by different MOTUs. We suggest that molecular and
taxonomic studies should be employed concurrently
in R. quelen, to prevent contamination of
wild species by hybridizations (Ribolli, J. et al.
2017). Remarks:
This species can still be found online (Fishbase)
as Rhamdia quelen with R. branneri
being a synonym off.
Common
Name:
None
Synonyms:
None
Family:
Heptapteridae
Distribution:
South America:
Iguaçu River basin (Brazil and Argentina).
Type locality: Creek of the Rio Iguaçú
near Serrinha, Paraná, Brazil.
Size:
30.0cm. (12ins)
Temp:
24-26°C (75-79°F)
p.H.
6.0-7.0.
Reference:
Ribolli, J., B. M.
Scaranto, O. A. Shibatta, R. A. Bombardelli and E.
Zaniboni-Filho 2017. DNA barcoding confirms
the occurrence of Rhamdia branneri and Rhamdia voulezi
(Siluriformes: Heptapteridae) in the Iguaçu
River Basin.
Rhamdia branneri Iguaçu River Basin, Paraná State,
Brazil
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