Theodosio De Stefani Perez was born in the family castle in Santa Ninfa (
Trapani) in southwestern Sicily, then in the
Kingdom of the Two Sicilies on 6 February 1853. He was a son of don Mariano De Stefani Falco and donna Ippolita Perez. He was the fourth of seven children. The father was the scion of a wealthy family of landowners, while the mother was a descendant of the Prince of Carloforte and heir to great wealth, but not the noble title. He completed his primary studies at the College of San Rocco, later he served voluntary military service until 1873 and at the end of this period he finished his studies. He became professor of entomology at the University of Palermo and in 1889 was appointed Chief of Phytopathology for Sicily. He was a member of many scientific academies and entomological and environmental associations. He learned the art of embalming and preservation of animals and contributed to establish the University Museum of Zoology and Comparative Anatomy of Palermo. He openly professed secularist, libertarian and antifascist ideas and adhered to
Freemasonry, where he held the highest degree of Worshipful Master, facts that led to his being ostracised by the fascist regime. Not interested in money, he did not draw his university salary for almost thirty years. Later he withdrew all his money at one time, but it was not enough to save him from the
economic collapse, with the loss of almost all of the family assets. He died in on 25 February 1935 at
Giacalone,
Palermo, aged 82. ==The Entomologist==