Criconema Hofmanner and Menzel, 1914
Andrassy (1979) observed that the genus Criconema, the type
genus of Criconematidae, was based on the description of Criconema
guernei which he considered species dubia because it was an
inadequate description of a juvenile nematode. Thus the genus name
Criconema is considered invalid and the species were transferred to
Ogma Southern, 1914. However, more recently, Geraert (2010)
accepts the valididity of the genus and retains the name
Criconema Hofmanner and Menzel, 1914.
Lobocriconema (De Grisse and Loof, 1965)
Nothocriconema (De Grisse and Loof, 1965)
Merocriconema (Raski and Pinochet, 1976)
Nenocriconema (Darekar and Khan, 1981)
Nothletus (Ebsary, 1981)
Nothocriconemella (Ebsary, 1981)
Paracriconema (Ebsary, 1981)
Amphisbaenema (Orton Williams, 1982)
Cerchnotocriconema (Bernard, 1982)
Criconema murrayi: scanning electron micrograph.
From Clark and Stone, 1976.
The various types of cuticular ornamentation are:
1. finely crenate
2. scale-like projections, if present, only on
posterior part of body
3. irregular, plate-like coverings on cuticle
over entire body (C. sheperdae) or on part of annules
4. ruffled, ribbon-like ornamentation encircling annule
on anterior surface (C. (giardi) guerni) or both anterior/posterior
5. cuticular fringe extending from posterior
margin of annules ( C. (giardi) guerni).
Labial region usually with six pseudo-lips, rounded and projecting forward
from the first annule. Annuli of labial region smooth; usually with one annule wider and clearly set off from the next succeeding body
separation is not distinct and labial region appears to bear two annules.
Stylet is 40 to 132 µm long.
Vulva located on the 4th to the 21st annule from terminus, slit-like or
completely closed by overhanging anterior lip.
Tail is conoid-pointed to bluntly rounded.
Juveniles: Cuticle with scale-like cuticular appendages over
entire body, usually with refractive elements or spine-like extensions
at distal ends, arranged in 8 to 24 longitudinal rows.
[Ref: Raski & Luc, Rev. Nematol. 10(4):409-444 (1987), H.
Ferris, Geraert (2010).]
feed ectoparasitically on root tips or along more mature roots. The
nematodes are migratory unless soil pore
space limits their movement.
These nematodes exhibit characteristic slow, sluggish movement.
Extraction poor except with sugar/centrifuge.
Andrassy, I. 1979.
Revision of the subfamily Criconematinae Taylor 1936 (Nematoda). Opuscula
Clark, S.A. and A.R. Stone, 1976. Nematologica 21:256-266.
Cordero, M. A. Robert T. Robbins, Allen L. Szalanski.
2012. Taxonomic and Molecular Identification of Bakernema, Criconema,
Hemicriconemoides, Ogma and Xenocriconemella Species (Nematoda: Criconematidae). J. Nematology 44:
Geraert, E. 2010. The Criconematidae of the World: Identification of the
Family Criconematidae. Academia Press, Gent. 615p.
Raski, D.J. and Luc, M. 1987. A reappraisal of Tylenchina (Nemata) 10.
The superfamily Criconemaroidea Taylor, 1936. Rev. Nemarol. 10:409-444.