(Mechelen, 1618 - Mechelin, 1667) was a Flemish Baroque painter who specialized in flowers.
Van Thielen was the son of a minor nobleman and eventually assumed the title of Lord of Couwenberch. In 1631 or 1632 he began studying at the age of thirteen with his future brother-in-law, the history painter Theodoor Rombouts (1597-1637), and in 1641 he commenced his studies with the flower painter Daniel Seghers (1590-1661). According to Houbraken (who mistakenly wrote his birth year as 1681 instead of 1618), his reputation during his lifetime was such that he received patronage from the Spanish crown,
