Three new freshwater nematode species found in Lake Baikal, Russia are described and illustrated.
Hofmaenneria longispiculata sp. n. is characterized by its long body (L=1475-2257 µm), absence of crystalloid bodies and somatic setae, long outer labial setae (16-23 µm long, 60-65% of labial region width), close location to anterior body end amphidial fovea, long and slender tail (c=7.0-9.5, c’=5.3-6.5), long spicules (97-112 µm long) and short gubernaculum. Eumonhystera abyssalis sp.n. is characterized by its long and comparatively thin body (L=1202-1540 µm, a=32-47), short outer labial setae (3-4 µm long, 26-31% of labial region width), close location to anterior body end amphidial fovea, long and thin spicules (45-48 µm long), and long and slender tail (c=5.2-6.8, c’=8.1-11.7).
Paramononchus baikalensis sp.n. is characterized by its long and stout body (L=1734-2168 µm, a=21-28), large buccal cavity (length 54-67 µm, width 22-25 µm), armed big dorsal tooth, presence of small denticles at longitudinal ridges in buccal cavity, long, thin and curved spicules (142-157 µm long), and short and stout tail (c=10.3-13.9, c’= 2.9-3.8).