In Argentina, there are 5 species of the genus Strategus cited:

S. surinamensis: for Misiones, Salta, and Corrientes.
S. argentinus: for Salta, Catamarca, Córdoba, Chaco, and Santiago del Estero.
S. validus: for Misiones, Salta, Jujuy, Tucumán, Buenos Aires, and Río Negro.
S. mandibularis: for Misiones.
S. centaurus: also for Misiones.

To differentiate the different species, it is necessary to examine the genitalia, so they cannot be distinguished by photographs. They can also be identified by geographic distribution where they do not overlap.

Comment by: Lucas Rubio