Metateratocephalus crassidens

The genus Metateratocephalus contains several species of bacterivorous nematodes of which at least one species - M. crassidens, described by the Dutch nematologists de Man in 1880 - occurs in the Netherlands. They are small nematodes, usually smaller than half a millimetre, which occurs in soil as well as in fresh-water.


Remarkable is that the terrestrial specimens never exceed 0.4 mm in length whereas the aquatic individuals reach a length between 0.4 and 0.5 millimetre. Do they belong to one and the same species? Also remarkable is the long generation time for such a small nematode. Adult specimens are usually found in winter; their density is highest in January. Juveniles reach their highest density in March.

More pictures of Metateratocephalus:

Metateratocephalus
Metateratocephalus

Metateratocephalus: lip with sclerotised edges deeply divided
Metateratocephalus: lip with sclerotised edges deeply divided

Metateratocephalus: head and oral cavity
Metateratocephalus: head and oral cavity
Metateratocephalus: head and oral cavity and oesophagus
Metateratocephalus: head and oral cavity and oesophagus
Metateratocephalus: oesophagus juvenile (basal bulb with transverse valves)
Metateratocephalus: oesophagus juvenile (basal bulb with transverse valves)
Metateratocephalus: oesophagus juvenile (basal bulb with transverse valves)
Metateratocephalus: oesophagus juvenile (basal bulb with transverse valves)
Metateratocephalus: oesophagus juvenile
Metateratocephalus: oesophagus juvenile
Metateratocephalus: oesophagus
Metateratocephalus: oesophagus
Metateratocephalus: vulva region
Metateratocephalus: vulva region

Metateratocephalus: tail
Metateratocephalus: tail
Metateratocephalus: tail
Metateratocephalus: tail
Metateratocephalus: anal opening
Metateratocephalus: anal opening

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