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| Loricaria nimairaco Londoño-Burbano, Urbano-Bonilla, Thomas & Britto, 2023 |
Abstract
A new species of Loricaria is described from the upper Amazon River basin, Colombia. The new species is distinguished from its congeners primarily by having the dorsal portion of head with uniform black or dark brown coloration extending to three or four plates posterior to dorsal fin base, or with two longitudinal bands from tip of the snout to origin of dorsal fin; abdominal plates tightly joined and completely covering the median abdominal space and pectoral girdle; and pectoral and dorsal fins totally black or dark brown, without bands, spots, or blotches. The new species is further distinguished by plate counts, and body measurements. An analysis of genetic distances using the cytochrome oxidase c subunit 1 marker of the mitochondrial genome showed a clear differentiation between the new species and Loricaria cataphracta (5.8–7.6%), L. nickeriensis (5.7–6.1%), and L. simillima (2.7–7.0%). Species delimitation analyses were carried out, which further supported the new species as a divergent lineage within the genus. Fish species diversity of the upper Amazon River basin and taxonomic issues related to L. simillima are included as part of the discussion.
Keywords: COI; Orteguaza River; Putumayo River; Species delimitation analyses
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| Holotype of Loricaria nimairaco, ICN-MHN 24398, 185.8 mm SL, Colombia, Amazonas, Leticia, Amazonas River. Scale bar = 10 mm. Photos: Gabriel Cortés. |
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| Loricaria nimairaco, paratype, MPUJ 17399, 180.4 mm SL, Colombia, Putumayo, Puerto Asís, Putumayo River. Scale bar = 10 mm. Photos: Omar E. Melo-Ortiz. |
Loricaria nimairaco, new species
Diagnosis. Loricaria nimairaco can be distinguished from all congeners by the following combination of characters: dorsal portion of head to origin of dorsal fin with uniform black or dark brown coloration or the presence of two longitudinal stripes from tips of the snout to origin of dorsal fin, without transversal bands or spots (Figs. 1–2) vs. (dorsal portion without coloration, with spots, with transversal bars, or with dark transverse bar reaching nares and snout tip; Figs. 3– 5 ); abdominal plates tightly joined and completely covering the median abdominal space and pectoral girdle (Figs. 1–2) (vs. loosely joined, isolated or incompletely covering the pectoral girdle, except species from the Loricaria cataphracta group; Fig. 4); and by having dorsal and pectoral fins totally black or dark brown, without bands, spots, or blotches (Figs. 1–2) (vs. dorsal and pectoral fins hyaline or with dark bands, spots, or blotches ...
Etymology. The specific name nimairaco [nɨmáìraco] in the Uitoto-Muinane language from Peru, means “house of a wise man” (Minor, Hendrich-Minor, 2008:86). In tribute to our friend and colleague, José Iván Mojica, late professor of the Instituto de Ciencias Naturales de la Universidad Nacional de Colombia. His contributions to Colombian ichthyology (biology, ecology, systematics, and biogeography of freshwater fishes) have made it possible to advance in the conservation of the country’s fishes and rivers, such as the Amazon, the river that was always the home of the wise. A noun in apposition.
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| Environment at Putumayo River basin. A. Piedmont drainages “río Guineo”; B. Main channel of the Putumayo River in the lower part; and C. Streams of Terra-firme. Photos: Alexander Urbano-Bonilla. |
Londoño-Burbano A., Urbano-Bonilla A., Thomas M.R. and Britto M.R. 2023. A New Species of Loricaria (Loricariidae: Loricariinae) from the upper Amazon River Basin, Colombia. Neotrop. ichthyol. 21 (03) DOI: 10.1590/1982-0224-2023-0008
