Hypanus rubioi
A large-bodied benthic predator with a distinct elongated snout.
Hypanus rubioi, called the longnose pacific stingray, belongs to the stingray family Dasyatidae. This cartilaginous fish lives only in the coastal waters of the Eastern tropical Pacific Ocean, off the Pacific coast of Colombia. First described as a new species in early 2025, it stands out because of its very long, sharp snout and slender tail, features that set it apart from other stingrays in the same area.
Marine biologists P. A. Mejía-Falla, A. F. Navia, D. Cardeñosa, and J. Tavera formally named the species. Their description appeared on February 18, 2025, in the journal *Ichthyology & Herpetology*. Before this, populations of *H. rubioi* may have been mistaken for other long-snouted rays in the Eastern Pacific because their body shapes are similar. The holotype, a large individual measuring 1,897 mm (74.7 inches) total length, was used to define the species. Finding *H. rubioi* highlights the need for more detailed studies of body form and genetics in the Eastern Tropical Pacific, an area with many undocumented marine species and hidden species groups among sharks and rays.
*H. rubioi* is a large ray for its genus, reaching a disc width of about 1,250 mm (49.2 inches). Its body follows the usual stingray shape but has special proportions suited to its way of life.
The pectoral disc is roughly as wide as it is long, or slightly wider, with the disc length fitting 1.0 to 1.1 times into the width. The front edges of the disc curve inward, leading to a long, pointed snout. The rostrum angle ranges from 93° to 105°. The distance from the snout tip to the mouth is very long, making up 28% to 32% of the disc width. On the underside, the nostrils are spaced 9% to 11% of the disc width apart, and the first gill slits are 17% to 19% of the disc width apart. The eyes are small relative to the body, with an eye diameter of only 1.7% to 3.4% of the disc width. The space between the eyes is 4 to 9 times the eye diameter.
The tail is extremely long and slender, measuring 2.4 to 3.1 times the length of the pectoral disc. Near the pelvic fins, the tail is about as wide as it is tall (0.6 to 1.1 times), with a cylindrical base that tapers quickly. On the underside, there is a low, thin fin fold. This fold’s length is 1.6 to 2.7 times the disc width, and it is very shallow—its length is 13 to 25 times its depth behind the pelvic fin.
Quick Facts
- Genus
- Hypanus
- Species
- rubioi
Facts from the source article.
Lore & Background
Hypanus rubioi was formally described by marine biologists P. A. Mejía-Falla, A. F. Navia, D. Cardeñosa, and J. Tavera, with the official species description published on February 18, 2025, in the peer-reviewed journal Ichthyology & Herpetology. Prior to its formal taxonomic description, populations of H. rubioi may have been misidentified or grouped alongside other similar long-snouted rays native to the Eastern Pacific region due to subtle morphological overlaps within the genus Hypanus. The holotype specimen is a large individual measuring 1,897 mm (74.7 in) in total length.
The pectoral fin disc of H. rubioi is roughly equal in width to its length, or slightly wider, with the disc length fitting 1.0 to 1.1 times into the disc width. The front-side margins of the pectoral disc are distinctly concave, leading to a highly specialized, elongated snout. The rostrum is pointed and protrudes sharply, with a rostrum angle between 93° and 105°. The preoral length is exceptionally long, representing 28% to 32% of the total disc width. The eyes are relatively small, with the eye diameter measuring only 1.7% to 3.4% of the disc width, and they fit 4 to 9 times within the interorbital distance.
One of the most prominent features is its extremely long and slender tail, which measures between 2.4 and 3.1 times the entire length of the pectoral disc. The tail features a low and slender ventral fin fold, with its length proportional to 1.6 to 2.7 times the disc width and extremely shallow. The distance from the anterior cloaca to the venomous caudal sting fits 0.4 to 0.8 times into the precloacal length.
Reader's Guide
The discovery of Hypanus rubioi underscores the ongoing need for detailed morphological and genetic assessments in the Eastern Tropical Pacific, a region known for high levels of undocumented marine biodiversity and cryptic species complexes among elasmobranchs. As a large-bodied benthic predator endemic to the Pacific coast of Colombia, its formal description in early 2025 clarifies a previously ambiguous taxonomic status, where populations may have been misidentified alongside other long-snouted rays. The species' distinct morphometric proportions—including its exceptionally long snout, elongated slender tail, and small eyes—provide clear diagnostic features that separate it from sympatric stingrays. Its description adds to the understanding of the genus Hypanus and highlights the importance of continued survey work in coastal marine ecosystems of the Eastern tropical Pacific.
Did You Know?
- The holotype specimen of Hypanus rubioi measures 1,897 mm (74.7 in) in total length.
- Its preoral length represents 28% to 32% of the total disc width.
- The species was formally described on February 18, 2025, in the journal Ichthyology & Herpetology.
More in Reef Sharks and Rays 1-24
Spotted an error? Know more?
Reader corrections go straight into our review queue. Suggest an edit · How this site is sourced