Length–weight relation for seven Neotropical freshwater fish species (Actinopterygii) endemic to Central America

In the presently reported study, we estimated length–weight relation (LWRs) for seven species of freshwater fishes from Central America. Samples were collected using seines from 60 sites across Nicaragua, Costa Rica, and Panama during field expeditions conducted between 1997 and 2012. The fishes were preserved and transported to the lab, where their total weight (W) was measured (to nearest 0.0001 g) and standard lengths were taken (to nearest 0.01 mm). Data were collected from four livebearers (Poeciliidae), Alfaro cultratus (Regan, 1908), Phallichthys amates (Miller, 1907), Poecilia gillii (Kner, 1863), and Priapichthys annectens (Regan, 1907); the cichlids (Cichlidae), Parachromis dovii (Günther, 1864) and Parachromis managuensis (Günther, 1867); and a silverside (Atherinopsidae), Atherinella hubbsi (Bussing, 1979). Estimates of parameter b ranged from 2.936 (A. hubbsi) to 3.696 (P. gillii), while estimates of parameter a ranged from 1.7 × 10−6 (P. gillii) to 1.9 × 10−5 (P. managuensis). Parameter b estimates were greater than three, consistent with allometric growth, with the exception of P. annectens, P. managuensis, and A. hubbsi, for which t-tests failed to reject the null hypothesis of isometric growth. Our results provide the first LWR information for five (71%) of these species and may prove useful for data imputation or estimating the biomass of poeciliid, cichlid, and atheriniform fishes in Central American rivers in the future.