Common Name
Mexican Halfbeak
Year Described
Álvarez, 1959
Identification
Dorsal Fin: 15
Anal Fin: 13-15
Pectoral Fin: 10-11
Pelvic Fin: 6
Gill Rakers: 19-20 (17-19 on lower limb of first arch)
Body relatively slender. Preorbital ridge present and snout covered in scales. Lower jaw elongate. Dorsal and anal fins without scales, or scales restricted to anterior part of fin. Pectoral fin relatively short: does not extend past nasal opening when depressed forward*. Caudal fin moderately forked, with lower lobe enlarged.
Color
Body pale to silvery with a silver lateral stripe widening posteriorly. Lower jaw with red tip. Caudal fin with dark posterior border.
Size
Maximum size to 16cm SL.
Habitat
A freshwater species that can be found near the mouth of the Rio Usumacinta.
Range
Endemic to the Usumacinta and Papaloapan river systems of eastern Mexico.
References
Contreras-Balderas, S., M.L. Lozano-Vilano, and M.E. Garcia Ramirez. 1997. Distributional and ecological notes on the halfbeaks of eastern Gulf of Mexico, with a provisional key for their identification. Gulf Research Reports. January 94: 327-331.
Miller, R. R. 2006. Freshwater fishes of México. Chicago. University of Chicago Press. xxvi + 1-490.
Other Notes
Included as it is closely allied to the other marine species in the genus.