 In 1995 scientists discovered the first non-"Euglena" twintron in cryptomonad alga "Pyrenomonas salina".In 2004, several twintrons were discovered in "Drosophila".The majority of these twintrons have been characterized within the "Euglena" chloroplast genome but these elements have also been found in cryptomonad algae ("Pyrenomonas salina"), and group I intron based twintrons (group I inserted within a group I intron) have been described in "Didymium iridis".