In the meantime someone in an other forum had solved this question!

“There was a Ft Lauderdale-based company called State Airlines, which began operating in late 1981 between FLL and SRQ. In 1982 it was also serving FMY and TLH. This was basically a Cessna 402/Piper Navajo operation. In 1983 it added routes from FLL and PBI to several points in the Bahamas.

In early 1984 it acquired the business of a company called Southeast Airlines, which was the southern division of parent, Starflight International. The merged carrier was called “Southeast State”.

Along the way it acquired said Heron, a Dove, and a Nomad.”