Centropomus
Centropomus is a genus of predominantly marine fish comprising the family Centropomidae. The type species is "Centropomus undecimalis", the common snook. Commonly known as snooks or róbalos, the "Centropomus" species are native to tropical and subtropical waters of the western Atlantic and eastern Pacific Oceans. Prior to 2004, the subfamily Latinae, which contained three genera, was placed within the Centropomidae; this has since been raised to the family level and renamed Latidae because a cladistic analysis showed the old Centropomidae to be paraphyletic. This has left "Centropomus" as the only remaining genus in this family. These are popular game  and food fish. Dating from the upper Cretaceous, the centropomids are of typical percoid shape, distinguished by having two-part dorsal fins, a lateral line that extends onto the tail, and frequently, a concave shape to the head. They range from in length and are found in tropical and subtropical waters. The snook species range in maximum length from about , with maximum recorded weights of 1.0 – 26 kg (2.2 – 57 lb). Occurring in a variety of habitats ranging from coral reefs to estuaries and mangrove swamps, the snooks are carnivorous, feeding primarily on crustaceans and other fishes. Many of the  snooks are important as commercial food fish and as game fish. The generic name "Centropomus" derives from the Greek κέντρον (centre, in this sense "sting") and πώμα (cover, plug, operculum). "Róbalo" or snook are world-renowned game fish of the family Centropomidae and genus "Centropomus" that are much sought after by fly-fishing enthusiasts and sportfishing charters. Six Atlantic and six Pacific Ocean species are currently recognized as scientifically valid. All are known to inhabit Central America and all are excellent gamefish. No evidence has been found of the individual species crossing from the Atlantic to the Pacific or vice  versa through the Panama Canal. All snook species are capable of inhabiting both fresh and saltwater and are known to seasonally occupy Gatun Lake, which forms a water bridge connecting the Atlantic and Pacific Oceans as an integral part of the Panama Canal. Of the 12 species, only four are known to reach sizes in excess of 10 lb – two Atlantic species ("C. undecimalis" and "C. poeyi") and two Pacific species ("C. viridis" and "C. nigrescens"). The eight species of smaller snooks usually grow to less than 6 lb and can be readily distinguished by from the four larger species  by their noticeably longer anal spine, anal fin configuration, and body shape. The four large species are immediately recognizable by their more streamlined appearance given by their longer, narrower body shape. Many individual species bear a close resemblance to one another, although they may be from the same or different oceans; identification is better left up to experts. The two Atlantic large species ("C. undecimalis" and "C. poeyi") are virtually identical in appearance. They can usually only be distinguished by the number of gill rakers each possesses. The "robalo" or common snook ("C. undecimalis") commonly has 11 to 13 nonrudimentary  gill rakers and the Mexican snook ("C. poeyi") is most often found to possess 15 to 18 nonrudimentary gill rakers. The Pacific "robalo nato" or white snook ("C. viridis") is also a dead ringer for the common snook. The distinguishing feature is also the nonrudimentary gill raker count with 13 to 15 for the white snook. They act, breed, grow, and fight virtually the same. Curiously, laboratory-reared specimens of the common snook showed meristic variations in vertebrae, fin ray, and gill raker numbers not observed in specimens from the wild. These variations are suspected to be due to diet  and growth rates. Large "robalo" caught in Lake Gatun invariably cause a wealth of confusion. The IGFA requires verification of the species by a designated authority for world-record claims. The two Pacific species of large "robalo" are somewhat easier to distinguish. The "robalo redondo" or black snook ("C. nigrescens") can be differentiated by three visually apparent characteristics when compared to the "C. viridis" In culture. The United States Navy, submarines named USS "Robalo" and USS "Snook" are named for the common snook. Snook or Robalo types as game fish References. Reference www.panamafishingandcatching.com at "http://www.panamafishingandcatching.com/1-bayano.htm"