Diphĭlus in Harpers Dictionary of Classical Antiquities
（Δίφιλος). A poet of the new Attic comedy, a native of Sinopé, and contemporary of Menander. He is supposed to have written some one hundred pieces, of which we have the titles and fragments of about fifty. The Casina and Rudens of Plautus are modelled on two plays of Diphilus; and Terence has adopted some scenes from one of them (the Συναποθνῄσκοντες) in his Adelphoe. Diphilus took his subjects both from common life and from mythology. Most of the passages that have been preserved relate to matters of cookery, the longest being one of forty-one lines. Both the judgments passed on him in antiquity and his remaining fragments justify us in recognizing him as one of the most gifted poets of his age. These fragments are collected in Meineke, i. pp. 445-457; iv. pp. 375-430.
Diphilus in Wikipedia
Diphilus, of Sinope, was a poet of the new Attic comedy and contemporary of Menander (342-291 BC). Most of his plays were written and acted at Athens, but he led a wandering life, and died at Smyrna.
He was on intimate terms with the famous courtesan Gnathaena (Athenaeus xiii. pp. 579, 583). He is said to have written 100 comedies, the titles of fifty of which are preserved. He sometimes acted himself. To judge from the imitations of Plautus (Casina from the Κληρούμενοι, Asinaria from the Ὀναγός, Rudens from some other play), he was very skilful in the construction of his plots. Terence also tells us that he introduced into the Adelphi (ii. I) a scene from the Συναποθνήσκοντες, which had been omitted by Plautus in his adaptation (Commorientes) of the same play.
The style of Diphilus was simple and natural, and his language on the whole good Attic; he paid great attention to versification, and was supposed to have invented a peculiar kind of metre. The ancients were undecided whether to class him among the writers of the New or Middle comedy. In his fondness for mythological subjects (Hercules, Theseus) and his introduction on the stage (by a bold anachronism) of the poets Archilochus and Hipponax as rivals of Sappho, he approximates to the spirit of the latter.
Fragments in R. Kassel-C. Austin, "Poetae Comici Graeci" (PCG) vol. 5 (previously in T. Kock, Comicorum Atticorum fragmenta ii; see J. Denis, La Comédie grecque (1886), ii. p. 414; R.W. Bond in "Classical Review" 24/1 (Feb. 1910) with trans. of Emporos fragm.).