New Species of the Genus Hypanus (Dasyatidae) from the Eastern Tropical Pacific Ocean
A new species of stingray belonging to the genus Hypanus is described in this study based on data collected in the Eastern Tropical Pacific (ETP) region of Colombia. This new species stands out within the genus by its unique spade-shaped disc with a width-to-length ratio ranging from 1.0 to 1.1, whereas its obtuse snout extends 29–30% of the disc width (DW). This species also stands out due to its large size (125 cm DW). Notably, it has three distinctive rows of enlarged denticles on its mid-scapular area, with the central row extending back to the caudal sting. Additionally, it possesses a long tail that measures 2.2–2.5 times the DW, tapering smoothly. Molecular data also revealed significant differences between this new species and its congeners using COI. The phylogenetic analysis recovered Hypanus rubioi, new species, as the sister species to the western Atlantic Longnose Stingray H. guttatus, with an uncorrected genetic distance of 2.27 to 2.94%. The preliminary ecological niche modeling further indicates that this newly described species is likely associated with coastal regions in the ETP, ranging from central Mexico to northern Peru, with backlight and salinity as the most influential variables. These findings contribute to our understanding of the biodiversity within the genus Hypanus and the ecological distribution of this novel species in the ETP. Se describe una nueva raya del género Hypanus del Pacífico oriental tropical (POT) a partir de material colectado en el Pacífico de Colombia. La nueva especie es única dentro del género por ser de gran tamaño (125 cm de ancho de disco [AD]) con un disco romboidal en forma de pala, su anchura 1,0 a 1,1 veces su longitud, un hocico obtuso, rostro prolongado de punta extendida, 29–30% en AD, tres filas de dentículos agrandados en la parte media de la escapula, la hilera central se extiende hacia atrás hasta el aguijón caudal, cola larga, 2,2–2,5 veces el AD, estrechándose suavemente. Se diferencia de todos sus congéneres también por diferencias moleculares del gen COI. El análisis filogenético encontró que Hypanus rubioi sp. nov. es la especie hermana de la raya laya látigo hocicona del Atlántico occidental H. guttatus, con una distancia genética no corregida de (2,27 a 2,94%). El modelado preliminar del nicho ecológico indica además que esta especie recién descrita está probablemente asociada a regiones costeras del POT, que abarcan desde el centro de México hasta el norte de Perú y donde la luz de fondo y la salinidad fueron las variables con mayor influencia en el resultado. Estos resultados contribuyen a nuestra comprensión de la biodiversidad dentro del género Hypanus y la distribución ecológica de esta nueva especie en el POT.

Distribution of localities where specimens of Hypanus rubioi, new species, were collected in the Colombian Pacific Ocean.

Dorsal view of the holotype of Hypanus rubioi, new species, CIRUV-021336, male, 1,897 mm disc width, from Bahía Málaga, Colombia.

Comparative morphology of the three sympatric species of the genus Hypanus in the Tropical Eastern Pacific. Scale bars = 10 cm.

Body images of holotype of Hypanus rubioi, new species, CIRUV-021336. (A) Eye and spiracle, (B) spines of the tail, (C) oronasal region, (D) dorsal thorns, (E) lateral view of the tail, (F) ventral view of claspers. Scale bars = 1 cm.

(A) Distribution of length frequencies of males and females, (B) relationships between disc length and width by sex, (C) maturity stages of males and their relationship with disc width, (D) count of growth bands in a vertebra of a specimen of Hypanus rubioi, new species. BB = birth band.

Environmental suitability map of Hypanus rubioi, new species, in the Tropical Eastern Pacific. Coast of central México (A), southern México, Guatemala, El Salvador, Honduras, Nicaragua, and Costa Rica (B), Panamá (C), Colombia (D), and Ecuador and northern Perú (E).

Specimens of Hypanus rubioi, new species, caught in artisanal fishing operations in Charambirá, Colombian Pacific Ocean (courtesy of WCS Colombia, Julian Caicedo).

Bayesian maximum clade credibility COI tree of nine available species of Hypanus. Nodes are coded according to posterior probability (pp). Black circles correspond to a support value of 1. Gray circles correspond to 0.75–0.95 pp. White circles indicate 0.75 pp or below. See Data Accessibility for tree file.
Contributor Notes
Associate Editor: M. T. Craig.