More info on IGDB

Salamander was ported to the Family Computer in Japan in 1987. Instead of being a direct port of Salamander, elements were taken from the original Salamander and the Japanese Life Force re-release, and some elements, such as levels and bosses, were removed to make way for new content. Most of the background graphics and enemy sprites from Salamander are used in favor of those used in Life Force, though the Gradius-style power bar is used in place of the original instant pick-up system. The same year, North America received a port as well for the Nintendo Entertainment System. The NES version is practically identical to its Famicom equivalent, other than not having the multiple endings, having two option power ups instead of three, and being titled Life Force.