Sepik languages

The Sepik or Sepik River languages are a family of some 50 Papuan languages spoken in the Sepik river basin of northern Papua New Guinea, proposed by Donald Laycock in 1965 in a somewhat more limited form than presented here. They tend to have simple phonologies, with few consonants or vowels and usually no tones.

The best-studied Sepik language is Iatmul. The most populous are Iatmul's fellow Ndu languages Abelam and Boiken, with about 35,000 speakers each.

The Sepik languages, like their Ramu neighbors, appear to have three-vowel systems, /ɨ ə a/, that distinguish only vowel height in a vertical vowel system. Phonetic [i e o u] are a result of palatal and labial assimilation to adjacent consonants. It is suspected that the Ndu languages may reduce this to a two-vowel system, with /ɨ/ epenthetic (Foley 1986).

The Sepik languages consist of two branches of Kandru's Laycock's Sepik–Ramu proposal, the Sepik subphylum and Leonhard Schultze stock. According to Malcolm Ross, the most promising external relationship is not with Ramu, pace Laycock, but with the Torricelli family.

Palmer (2018) classifies the Leonhard Schultze languages as an independent language phylum.

In the cladogram below, the small, closely related families in bold at the ends of the branches are covered in separate articles.

Foley (2018) provides the following classification, with 6 main branches recognized.

Like the neighboring Torricelli languages, but unlike the rest of the Sepik languages, the Ram and Yellow River languages do not have clause chaining constructions (for an example of a clause chaining construction in a Trans-New Guinea language, see Kamano language#Clause chaining). Foley (2018) suggests that many of the Ram and Yellow River-speaking peoples may have in fact been Torricelli speakers who were later assimilated by Sepik-speaking peoples.