Periodic tense

Periodic tense is a subtype of the grammatical category of tense, which encodes that the event expressed by the verb occurs within a particular period of the day or of the year. Its does not encode a relation to a particular point of reference, unlike deictic tense, the grammatical expression of time reference relative either to the moment of speaking or to another point of reference.
Periodic tense is geographically restricted to Northern America, the Western Amazon region, the Sepik region, Arnhem land and it is almost entirely absent from languages of Africa and Eurasia, which the exception of Chukotkan languages.

Periodic tense in Nez Perce

Periodic tense can be illustrated with data from Nez Perce, which has one of the richest paradigms, comprising matutinal, diurnal, vesperal, nocturnal and hivernal, as illustrated in the following examples

Reconstructibility

Periodic tense systems are at least partially reconstructible in some language families. In proto-Sahaptian for instance, nocturnal *têw- and matutinal *mêy-, from which Nez Perce nocturnal te·w- and matutinal méy- above originate, have been reconstructed by Aoki.
In Tacanan languages, four periodic tense markers are reconstructible, whose reflexes in Cavineña or the following: diurnal -chinepe, nocturnal -sisa, auroral -wekaka and vesperal -apuna.

Attested subtypes

16 subtypes of periodic tense markers have been identified in Jacques, with a latinate terminology for each specific time period.

Period	Term	Example	Reference
at dawn		Cavineña -wekaka	Guillaume
in the morning		Nez Perce mey-	Aoki
at noon		Berik	Westrum
in the afternoon		May River Iwam -tep	Foley
in the evening		Nez Perce kulewi-	Aoki
in the night		Nez Perce te·w-	Aoki
during the day		May River Iwam -harok	Foley
all day		Chácobo =baina	Tallman
all night		Jarawara =haba	Dixon
until dawn		Awtuw =alw	Feldman
until noon		Omaha -míthumoⁿshi	Marsault
until afternoon	?	Alamblak -krif	Bruce
until nightfall		Omaha -hoⁿ	Marsault