Natrix is a genus of Old World snakes found mainly across Eurasia (although the range of Natrix tessellata extends into Egypt and those of N. astreptophora and N. maura into north-west Africa) in the subfamily Natricinae of the family Colubridae. They are commonly called grass snakes and water snakes, but some other snake species also known commonly as "grass snakes" and "water snakes" are not in the genus.
Species The genus Natrix contains five extant species. www.reptile-database.org. and at least five extinct (fossil-only) species. Image Scientific name Common name Distribution Natrix astreptophora Iberian grass snake Iberian peninsula (Spain and Portugal), southern France, coastal north-west Africa (Morocco, Algeria, Libya, Tunisia) Natrix helvetica barred grass snake Western Europe, including southern Great Britain Natrix maura viperine water snake"Natrix Laurenti, 1768". Encyclopedia of Life. http://eol.org/pages/35261/overview Portugal, Spain, France, north-west Italy and into Switzerland; north-west Africa (Morocco, Algeria, Libya, Tunisia) Natrix natrix grass snake Mainland Europe from mid Scandinavia to southern Italy, to northern Middle East and Central Asia Natrix tessellata dice snake Much of Eurasia, and Egypt †Natrix longivertebrata extinct species (Pliocene, Miocene) Poland, Austria, France †Natrix merkurensis extinct species (Miocene) Czech Republic, France †Natrix mlynarskii extinct species (Eocene–Miocene) France †Natrix parva extinct species (Miocene) Poland †Natrix sansaniensis extinct species (Miocene) Czech Republic, France
Nota bene: A binomial authority in parentheses indicates that the species was originally described in a genus other than Natrix.
Etymology Natrix is classical Latin for a water snake. The word comes from a Proto-Indo-European root meaning "snake", with cognates in the Celtic and Germanic languages, the latter including the English adder. It was probably influenced through folk etymology by the Latin nare and natare meaning "swim"; it appears to be a grammatically feminine word for "swimmer".
Geography The refuge of a widely distributed Western European lineage regarding the barred grass snake commonly known as Natrix helvetica was most likely located in southern France and outside the classical refuges in the southern European peninsulas. One genetic lineage of the common grass snake (N. natrix) is also distributed in Scandinavia, Central Europe, and the Balkan Peninsula.
References
Further reading Laurenti JN (1768). Specimen medicum, exhibens synopsin reptilium emendatam cum experimentis circa venena et antidota reptilium austriacorum. Vienna: "Joan. Thom. Nob. de Trattnern". 214 pp. + Plates I-V. (Natrix, new genus, p. 73). (in Latin).