DESCRIPTION

Males: Head truncate with 6 labial and 4 cephalic papillae. Male with 23 genital papillae. The papillae usually distributed as follows: six pairs preanal and subventral, a single ventral preanal papilla, two pairs adanal, one pair postanal and subdorsal, and two pairs postanal and subventral. Spicule symmetrical, long and slender, yellowish brown, curved 45 - 65 degrees. Spicule head variable in shape, somewhat longer than wide. Shaft indistinct. Spicule tip blunt. Two internal ribs, the dorsal rib curved to ventral side at the posterior end, the ventral rib becomes slender or disappears slightly anterior to posterior end. Velum present, starting at the end of spicule head and terminating at about mid-spicule. Gubernaculum slender and long in lateral view, anterior end curved ventrally, posterior end truncate, rounded, or bifurcate. Ventral view of gubernaculum: bifurcate at the end, inner side of two branches parallel, the ends of corpus relatively truncate. A membrane structure connects the two branches. Ventral side of male tail slightly concave, which makes the tail appear slender. The tail terminus is truncate, without mucron for the 1 st generation male, but pointed for the 2nd generation male because of projection at the tail end. Without bursa.

Measurements: L= 1,620 um, W=91 um, EP= 116 um, NR=128 um, ES=164 um, D%=71, tail length=44 um, ABW=33.6 um, spicule length=74.6 um, spicule width=13 um, gubernaculum length==52 um, gubernaculum width=7.6 um , SW=2.22, GS=0.70.

Females: Anterior part as in males. Vulva located slightly posterior to mid-body. Uteri paired. Tail with postanal swelling, posterior part of tail usually slightly constricted in first generation female. The shape of projections variable, but never pointed or sharp. The tail tapers gradually in 2nd generation females.

Infective juveniles: Stoma and anus closed. Esophagus narrow and long. Bacterial chamber connected to the end bulb of the esophagus. Lateral field prominent, with 8 ridges. Tail tapered.

Measurements: Body length 1, 106 (933 - 1,296) um; body width 36 (34 - 41) um. Head to excretory pore = 82 (76 - 89) um. Head to nerve ring 109 (104 - 126) um. . Head to end bulb 156 (49 - 175) um. Tail length 88 (80 - 100) um. C = 1.26 (1.14 - 1.31). E = 0.94 (0.87 - 1.00).

Type host: unknown
Type locality: Shangtou, Guangdong province, July 1987
Type specimens: Holotype, allotype and paratypes were deposited in Insect Collection, Department of Plant protection, Southern China Agricultural University. Some paratypes were deposited in Specimen Collection, Biology Department,  Guangzhou Normal University.

Reference:
    Xu, Z, Wang, G. & Li,  X. 1991. A new species of the ngenus Steinernema (Rhabditida: Steinernematidae). Zoological Reasearch 12:17-20.