Dimensions. 12 females L = 0.96 - 1.11 mm. a = 34
- 41 b = 5.0 - 6.4 c = 13 -16 V = 50 - 54 Stylet
26 - 30 u long
6 males L = 1.00 - 1.12 mm. a = 36 - 46 b = 5.1 - 7.0
c = 11 -14 T = 42 - 59 per cent Stylet 27 - 30 u long
Female (holotype). L = 1.07 mm. a = 41
b = 5.3 c = 15 V = 51
Body cylindrical. Lip region rounded, set off from body contour
by constriction, bearing 6 annules. Labial framework heavily sclerotized
basally. Arching circumoral sclerotization faint. Stylet well
developed, 29 u long, with large
rounded knobs. Orifice of dorsal eophageal gland 2 u behind
stylet base. Median bulb elongate-oval. Excretory pore opens
at level of base of isthmus. Esophageal-intestinal valve large, hemispherical.
Spermatheca not seen. Tail
conoid, tapering to a bluntly rounded terminus, without striations.
Length of tail about 3 x anal body diameter. Cuticle coarsely annulated.
Lateral field with 6 incisures. Phasmids prominent, opening at middle
of tail.
Male (allotype). L = 1.02 mm a = 36
b = 5.1 c = 12 T = 59 per cent Stylet 30 u long.
Similar to female. Phasmids prominent, opening at middle of tail.
Bursa envelops tail. Gubernaculum simple, strongly curved ventrally.
Type host- Soil at roots of Artemisia sp.
Type locality- Five miles east of Winnemucca, Nevada
Tylenchorhynchus grandis is distinguished by the six lines in
the lateral field, the tapering subcyclindrical tail, the rounded lip region
that is set off by constriction, and the conspicuous basal lip sclerotization.
This species is similar to macrodens, from which it differs in having
a shorter spear, coarser cuticle annulation, and less conspicuous lip sclerotization.
T. grandis is known from the following localities: 5 miles
east of Winnemucca, Nevada; Yuma Mesa and Palm Springs, California;
Little Field, Sacaton, and Yuma, Arizona. All the specimens were
obtained from soil collected around the roots of desert plants.
(Description- Allen, 1955)
