Family Criconematidae
Taylor, 1936
SEM Photo Gallery- Kalsow Prairie, Iowa
SEM Photo Gallery- Maine potato
Photo Gallery- Missouri daylilly
SEM Photo Gallery- Missouri daylilly
DIAGNOSIS
Criconematoidea.
All stages vermiform:  Small to large animals (up to 1.9 mm).
Female:  Body sausage-shaped to cylindrical.  Cuticle thick, lacking a typical lateral field (sometimes marked by irregularities in body annuli and/or superficial longitudinal lines very variable within the same species).  Body annuli either retrorse, provided or not with lobation, crenation, scales or spines or rounded and covered or not with an extra cuticular layer.  Labial area variously shaped; submedian lobes absent or variously developed.  Labial sclerotization strong.  Stylet massive; cone much longer than base plus knobs; stylet knobs anchor-shaped or sloping backwards.  Isthmus very short; oesophageal glandular bulb markedly reduced.
Male:  No stylet.  Spicules variously shaped.  Caudal alae absent to well-developed.
Juveniles:  Cuticle showing same range of variations as in female, but in some groups juvenile and female may have different ornamentation; cuticular spines or scales, if present, arranged in longitudinal rows, stylet nonreduced, functional (lacking in some male J4 of Hemicycliophora species).

BIONOMICS
Female and juveniles always ectoparasitic on plant roots.

TYPE SUBFAMILY
Criconematinae  Taylor, 1936.

OTHER SUBFAMILY
Hemicycliophorinae  Skarbilovich, 1959.

RELATIONSHIPS
Criconematidae is most closely related to the Tylenchulidae by the oesophagus with well-developed median bulbar area with massive valvular apparatus, short isthmus and small posterior glandular region symmetrically arranged, not overlapping intestine.  Strong sexual dimorphism, males degenerate mostly without stylet.  The families are distinguished by strong annulation and thick cuticle Criconematidae (fine annulations, mostly thin cuticle in Tylenchulidae); swollen females in many Tylenchulidae not found in Criconematidae.
(Description- Raski & Luc, 1987)

Genera found:          at:
Criconema
Criconemoides
Crossonema
Discocriconemella
Ogma
Macroposthonia
Xenocriconemella