Ethmolaimus

Gagarin, Vladimir G. & Naumova, Tatyana V., 2016, Ethmolaimus riparius sp. n. and Paramononchus major sp. n. (Nematoda) from Lake Baikal, Russia, Zootaxa 4098 (3), pp. 582-592 : 587

Key to species of Ethmolaimus from freshwater bodies

1. Somatic setae extremely long, greater than or equal to labial region diameter in length............................... 2

- Somatic setae shorter, less than half of labial region diameter in length............................................ 4

2. L = 1.23–1.50 mm; spicules 45–50 µm long................................................... E. riparius sp. n.

- L <1.20 mm; spicules less than 40 µm long................................................................. 3

3. Length of cephalic setae equal to one labial region diameter; spicules 32–37 µm long........................ E. pilosus

- Length of cephalic setae is equal to one and half to labial region diameter, spicules 25–30 µm long............ E. lanatus

4. L = 1.71–1.91 mm; spicules 52–53 µm long........................................................ E. maximus

- L <1.2 mm long; spicules less than 50 µm long............................................................. 5

5. Excretory pore located at the stoma level; length of stoma is equal 1.2 labial region diameter................ E. derisorius

- Excretory pore located at the nerve ring level; length of stoma is equal 1.3–1.7 labial region diameter................... 6

6. Outer labial sensillae in the shape of short setae; dorsal tooth and subventral teeth of equal size.............. E. pratensis

- Outer labial sensillae in the shape of papillae; dorsal tooth almost larger than subventral teeth.......................... 7

7. L = 0.55–0.61 mm; V = 51–54%................................................................... E. zullini

- L> 0.7.............................................................................................. 8

8. L = 0.67–1.00 мм, с = 8.7– 9.2, V = 54%....................................................... E. parapratensis

- L = 0.72–0.85 mm;.c = 6.0, V = 48%............................................................ E. caudatus