Complex sentence: The most famous endemic species is Rhinanthus osiliensis-a rare little flower growing mostly in spring fens; rare and beautiful flowers are widespread-out of the 36 species found in Estonia, 35 of them are found on Saaremaa and neighbouring islands.
Split into simpler sentences: The most famous endemic species is Rhinanthus osiliensis, a rare little flower growing mostly in spring fens. Rare and beautiful flowers are widespread; out of the 36 species found in Estonia, 35 of them are found on Saaremaa and neighbouring islands.