Διοτρέφης, (Thuc. 8.64), was sent, B. C. 411, by the oligarchical revolutionists in the Athenian army at Samos, to take charge of the subject states in the neighbourhood of Thrace, and took the first step in pursuance of their policy towards the allies by establishing oligarchy at Thasos. Nicostratus, the general who fell at Mantineia, was son of a Diotrephes (Thuc. 4.119) : this therefore perhaps was a Diotrephes, son of Nicostratus. If so, it is an additional reason for thinking him distinct from Diitrephes, the destroyer of Mycalessus. [DIITREPHES.]
[A.H.C]A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890