=Synagoge epsilon735; Photius, Lexicon epsilon1708; and scholia to Oppian, Halieutica 2.512, where the headword (third person singular, present indicative active, of the verb e)pispe/rxw) occurs. For this verb, see also epsilon 2085.
Both Adler and (on Photius s.v.) Theodoridis variously cite the scholia to Homer, Odyssey 5.304, Hesychius epsilon5207-8, and the scholia to Thucydides 4.12.1, but these gloss different forms of the headword with different words for the glosses.
Both the headword verb and the present glossing verb, katepei/gw, can be either transitive or intransitive (see LSJ on both), so it is hard to tell which usage is exemplified here. If it is transitive, it might be quoted from Aeschylus, Seven Against Thebes 689, which attracted a good deal of scholiastic comment.