L = 0.7 mm; a = 35; b = 5.9; c = 35; V = 54
Body a tight spiral when relaxed. Cuticle with annules only 1u wide
near midbody. Lip
region conoid, without annules, ending in a distinct disc
which sometimes is slightly concave.
Spear 20u-23u long, somewhat shorter than those described
by Sher, with strong, slightly cupped knobs. Excretory pore about opposite
junction of esophagus and intestine, with hemizonid slightly anterior.
Apparently spermagonia were developing in the young females collected.
Terminus
variable, blunt, indented or elongate-conoid with 15-20
annules. Phasmids near middle of tail. Males not seen and spermatozoa
not present in uterine tract.
Helicotylenchus labiodiscinus is immediately
recognized by the discoid lip region, fine annulation and 15-20 caudal
annules.
Habitat: Six immature females
from lawn, Aberdeen, South Dakota.
(Description- Thorne and Malek, 1968)