Alaimus

The world-wide distributed bacterivores genus Alaimus was described by Dr. J.G. de Man in 1880 from the Netherlands (Type species = A. primitivus de Man, 1880). The Latin name Alaimus refers to mouthless, i.e. to the very small mouth cavity. It is not the only reduced morphological character present in this genus, as it also shows a smooth cuticle (no cuticular ridges), very small labial sensilla and pore-like amphids (posterior to the head region). The female genital system is opisthodelphic with a closed vulva and a narrow vagina. About 55 valid species are known at present and the genus is terrestrial (particularly in mosses) and can also be found in semi-aquatic (fresh water) environments. 

More pictures of Alaimus elongatus de Man, 1906 :

Alaimus elongatus: female anterior body
Alaimus elongatus: female anterior body

Alaimus elongatus: female posterior body
Alaimus elongatus: female posterior body

Alaimus elongatus: head region with pharynx (partly).
Alaimus elongatus: head region with pharynx (partly).

Alaimus elongatus: posterior part of pharynx
Alaimus elongatus: posterior part of pharynx

Alaimus elongatus: vulva with gonad (partly)
Alaimus elongatus: vulva with gonad (partly)

Alaimus elongatus: anal opening
Alaimus elongatus: anal opening
Alaimus elongatus: posterior tail part
Alaimus elongatus: posterior tail part

More pictures of Alaimus Meyli Andr√°ssy, 1961:

Alaimus meyli: female body
Alaimus meyli: female body

Alaimus meyli: head region with pharynx (partly)
Alaimus meyli: head region with pharynx (partly)
Alaimus meyli: vulva with gonad
Alaimus meyli: vulva with gonad

Alaimus meyli: anal opening
Alaimus meyli: anal opening

Alaimus meyli: tail region.
Alaimus meyli: tail region.

More pictures of Alaimus parvus Thorne, 11939:

Alaimus parvus: female body
Alaimus parvus: female body

Alaimus parvus: head region with pharynx (partly)
Alaimus parvus: head region with pharynx (partly)
Alaimus parvus: posterior part of pharynx
Alaimus parvus: posterior part of pharynx
Alaimus parvus: vulva with gonad
Alaimus parvus: vulva with gonad
Alaimus parvus: tail region
Alaimus parvus: tail region

(Click on the pictures for an enlargement, ©Wageningen University & Research, Laboratory of Nematology/Pictures: Hanny van Megen)