Keeltail needlefish, like all needlefish, closely resemble North American freshwater gars (family Lepisosteidae). It is most recognized by the large, flat keel-like structures running on either side of the tail.[3] They have 12 to 15 rays on their dorsal fins, and 17 to 20 rays on their anal fins. Keeltail needlefish have gill-rakers, their caudal peduncles have lateral keels,[4] with a lateral line running ventral to it, and grow up to 50 cm long [5]
The keeltail needlefish's top jaw is also smaller than the lower one.[3]
They school in sheltered parts of reefs,[9] feeding mainly on smaller fish. Keeltail needlefish are egg-laying, attaching their eggs to floating objects with specialized tendril-like structures on the egg's surface.[10]
P. argalus range map, with each major subspecies highlighted
Fishbase treats P.a. lovii as a valid species, Platybelone lovii,[11] while other authorities also treat P.a platyura and P.a. trachura as valid species.[2]
^Claro, R., 1994. Características generales de la ictiofauna. p. 55–70. In R. Claro (ed.) Ecología de los peces marinos de Cuba. Instituto de Oceanología Academia de Ciencias de Cuba and Centro de Investigaciones de Quintana Roo.
^ Robins, C.R. and G.C. Ray, 1986. A field guide to Atlantic coast fishes of North America. Houghton Mifflin Company, Boston, U.S.A. 354 p.
^Cervigón, F., R. Cipriani, W. Fischer, L. Garibaldi, M. Hendrickx, A.J. Lemus, R. Márquez, J.M. Poutiers, G. Robaina and B. Rodriguez, 1992. Fichas FAO de identificación de especies para los fines de la pesca. Guía de campo de las especies comerciales marinas y de aquas salobres de la costa septentrional de Sur América. FAO, Rome. 513 p. Preparado con el financiamento de la Comisión de Comunidades Europeas y de NORAD.
^Kuiter, R.H. and T. Tonozuka 2001 Pictorial guide to Indonesian reef fishes. Part 1. Eels- Snappers, Muraenidae - Lutjanidae. Zoonetics, Australia. 302 p.
^Breder, C.M. and D.E. Rosen, 1966. Modes of reproduction in fishes. T.F.H. Publications, Neptune City, New Jersey. 941 p.
