Revisión de la especie politípica Jaera nordmanni (Rathke, 1837) (Isopoda, Asellota, Janiridae) de las aguas dulces de Mallorca

Abstract

A revision of the polytypic species Jaera nordmanni (Rathke, 1837) (Isopoda, Asellota, Janiridae) from the freshwater of Majorca (Balearic Islands)
Two new sub-species of Jaera nordmanni are described from the continental waters of Mallorca: J. n. brevicaudata n., ssp. and J. n. balearica (Margalef, 1952). The former is characterized by its relatively short basipodites of uropodes (never exceeding the end of pleotelson), by a lacinia mobilis with five teeth, praeoperculum without «mucrons», and by the shape of the exopodite of the fourth pleopode without a constrained apex. The latter is characterized by a great number of compound spines on the fourth carpopodite of the male (16-18), lacinia mobilis with five teeth, and «mucrons» of praeoperculum scarcely developed. If J. n. occidentalis is so much morphobgically homogeneous as Veuille (1977, 1979) states, then J. n. balearica has to be maintained as a differenciated sub-species.