Valency-Conditioned Allomorphy in the Verbal Agreement of the Takestani Dialect of Southern Tati

This paper studies the morphological structure of verbs in Takestani, an endangered Iranian dialect of Southern Tati. We analyse the effects of various morphological conditions on subject agreement allomorphy. The agreement suffix exhibits a large range of allomorphs in the past tense. We show that the primary factor for the agreement allomorphy is the valency of the root, and secondary factors are the presence of auxiliaries or perfective aspect. We also propose that the agreement allomorphy is a long-distance process. The agreement allomorphy is conditioned by the voice or transitivity of the verb stem even though the stem is not directly adjacent to the agreement suffix. Alternative formulations in terms of clitics vs. suffixes do not negate the long-distance nature of this allomorphy. We also find morphomic patterns of behaviour, such that the verbal agreement suffixes are mobile and can alternatively surface as possessive suffixes on nouns.