EN
A description is provided of Longidorus balticus sp. nov., a bisexual species recovered from the rhizosphere of Elymns arenarias L. growing in coastal sand dunes in northeast Poland. The species is characterized by having a long (L=6.7-9.2 mm) and slender (a= 119-175) body; expanded labial region, flattened anteriorly; assymetrically bilobed amphids; anteriorly situated guide ring (23-29 µm); odontostyle of medium length (91-105 µm); and a short, rounded tail. Males having spicules of medium size (58-69 µm), and a row of 9-15 supplements. Longidorus baltieus sp. nov. has four juvenile developmental stages. Longidorus balticus sp. nov. resembles L. vineacola, L. belloi, L. lusitaniens, L. moesicus, L. profundorum and L. apulus.