Project Perseus seems to show some confusion or uncertainty, tagging the same form with different part-of-speech tags on different occasions.ἀνήνοθε [3 sing., in the first passage of a plupf. (with secondary person-ending), in the second of a pf., fr. ἀνεθ- + ἀνθ-, ἄνθος. (Cf. ἐνήνοθε)]. (ἐπ-.) To come to the surface, come forth: αἷμ’ ἀ. Λ266.-- To rise up, spread upwards: κνίση ἀ. ρ270.
Beekes says these are from Doric ἐνθεῖν, to come, go. I guess it's only a coincidence that the dictionary form looks similar to the ablative -θεν. He pooh-poohs Cunliffe's connection to ἄνθος. There is a Doric subjunctive ἔνθω for the verb ἦλθον/ἔρχομαι, but Beekes has the following technical note which, although I don't understand the details, seems to be saying this isn't so:
Is there actually anything mysterious or confusing here, or is this basically just a pretty regular perfect form, for a verb that only survived in one fossilized inflection?Since ἐνθεῖν is widespread in Doric, it is. not from ἐλθεῖν (with a limited
dialectal development λτ > ντ).