Mordvinic languages

The Mordvinic languages, also known as the Mordvin, Mordovian or Mordvinian languages,
are a subgroup of the Uralic languages, comprising the closely related Erzya language and Moksha language, both spoken in Mordovia.
Previously considered a single "Mordvin language",
it is now treated as a small language grouping. Due to differences in phonology, lexicon, and grammar, Erzya and Moksha are not mutually intelligible. The two Mordvinic languages also have separate literary forms. The Erzya literary language was created in 1922 and the Mokshan in 1923.
Phonological differences between the two languages include:

Moksha retains a distinction between the vowels while in Erzya, they have merged as.
In unstressed syllables, Erzya features vowel harmony like many other Uralic languages, using in front-vocalic words and in back-vocalic words. Moksha has a simple schwa in their place.
Word-initially, Erzya has a postalveolar affricate corresponding to a fricative in Moksha.
Next to voiceless consonants, liquids and the semivowel are devoiced in Moksha to.

The medieval Meshcherian language may have been Mordvinic or close to Mordvinic.

Classification

Traditionally, Uralicists grouped the Mordvinic and Mari languages together in the so-called Volgaic branch of the Uralic family; this view was however abandoned in the late 20th century. Instead, some Uralicists now prefer a rapid expansion model, with Mordvinic as one out of nine primary branches of Uralic; others propose a close relation between Mordvinic with the Finnic and Saamic branches of Uralic.