Proto-Indo-Iranian
Proto-Indo-Iranian or Proto-Indo-Iranic is the reconstructed proto-language of the Indo-Iranian/Indo-Iranic branch of Indo-European. Its speakers, the hypothetical Proto-Indo-Iranians, are assumed to have lived in the late 3rd millennium BC, and are often connected with the Sintashta culture and the early Andronovo archaeological horizon.
Proto-Indo-Iranian was a Satem language, likely removed less than a millennium from the late Proto-Indo-European language, its ancestor, and in turn removed less than a millennium from the Vedic Sanskrit of the Rigveda, its descendant. It is the ancestor of the Indo-Aryan languages, the Iranian languages, and the Nuristani languages.
alveolar
alveolar
In addition to the vowels, *H, and *r̥ could function as the syllabic core.
Proto-Indo-Iranian is hypothesized to contain two series of stops or affricates in the palatal to postalveolar region. The phonetic nature of this contrast is not clear, and hence they are usually referred to as the "primary"/"first" series (*ĉ *ĵ *ĵʰ, continuing Proto-Indo-European palatovelar *ḱ *ǵ *ǵʰ) and the "second(ary)" series (*č *ǰ *ǰʰ, continuing Proto-Indo-European plain and labialized velars *k⁽ʷ⁾ *g⁽ʷ⁾ *gʰ⁽ʷ⁾ in palatalizing contexts). The following table shows the most common reflexes of the two series (Proto-Iranian is the hypothetical ancestor to the Iranian languages, including Avestan and Old Persian):
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