[Morphometric variation and ecologic characteristics of the habitat of the Kinosternon scorpioides turtle in Costa Rica (Chelonia,Kinosternidae)].

Kinosternon scorpioides shows sexual dimorphism in Costa Rica. Males are bigger than females since in the length of the shell ranges between 15.0-17.5 cm (average: 16.10 cm) and in these ones between 12.4-15.9 cm (average: 13.8 cm). According to the Life Zone System of Holdridge, K. scorpioides is in two geographic regions with different characteristics, one situated in the tropical dry forest zone and the other in tropical very rain forest. Morphometric variation is evident since females, more rounded, are in the first life zone, and males, more elongated, in the second zone. Shape and size of the shell of the turtles is a fit adaptation in their habitats because the average height of the shell of the turtles in tropical very rain forest is smaller than the average height in the tropical dry forest. This means that turtles of tropical very rain forest are more smoothed and more hydrodynamics than the others, which might to be advantageous for the swim very quickly and to hide out in the numerous tunnels or caves on the banks of the streams when they are attacked by jaguars or other predators. This life zone has several perennial streams without rocks, while on tropical dry forest zone, small seasonal lakes and marshes prevail during all year with abundant aquatic vegetation which obstructs the free displacement of the turtles. Likewise, the tropical very rain forest zone has 80% of turtles with physical damages produced by jaguars, while in tropical dry forest none of them shows this type of damages.