Thorne & Malek, 1968
L = 0.7 mm; a = 33; b = 4.3; c =
15;V = 82
L = 0.6 mm; a = 38; b = 5.3; c = 14; T
Cuticle with annules about 1.3u wide at midbody. Lateral fields
obscure, about 1/4 body width, marked by 4 fine lines. Lip
region low, flat. Spear only 8u long with moderate sized knobs,
its muscles attached to basal plate of cephalic armature. Median
bulb elongate fusiform with strong refractive valve near center.
Isthmus about 3 times neck width with nerve ring slightly anterior to middle.
bulb elongate pyriform with 3 large nuclei. Excretory pore and
hemizonid well anterior to bulb. Anterior intestinal cells hyaline,
attached to bulb by obscure valvular apparatus. Intestinal lumen
narrow, tenuous. Vagina
1/3 across body. Ovary outstretched, oocytes in single file.
Poterior uterine branch as long as body width. Tail
as long as vulva-anus distance. Tails of both sexes arcuate to pointed
terminus. Male more slender
than female with wide bursa
extending to near middle of
tail, where it is attached to a ventral elevation.
Ditylenchus microdens is distinctive because of the small spear,
tail shorter than vulva-anus distance, broad bursa extending to near middle
of tail and pointed terminus in both sexes.
Habitat: Cultivated fields near Avon, Gary, Huron, Presho and
Brookings, South Dakota. Also from fields near Holbrook and Fairmont,
DNA Sequences Obtained