As transmitted, here and in other lexica, headword and gloss are both presenbt active participles in the masculine dative singular. At Photius upsilon218, however, Theodoridis obelizes them both and expresses support for Naber's view that both -- by a change of suffix from i to ai -- should be present indicative middle, third person plural. (Normally these verbs are indeed middle voice.) See Homer, Iliad 7.407, with scholion.