elevated structures are sometimes visible at the base of each lip;
amphidial opening small.
3. Stoma wide but shallow; cheilorhabdions exist, forming a ring,
in lateral view resembling two refractile dots.
4. Other parts of the stoma fused to form a collapsed posterior
portion. Posterior part of stoma enclosed by esophagus.
5. Esophagus without metacorpus; isthmus slender; basal bulb
swollen; valve in basal bulb reduced.
6. Nerve ring at the center of isthmus.
7. Excretory pore generally posterior to end of esophagus.
8. Vulva median, slit-like, bounded by elliptical rings; ovotestis
amphidelphic, reflexed.
9. Oviparous, later becoming ovoviviparous.
10. Tail pointed, longer than anal body width, postanal swelling
usually present.
Amphimictic Female
1. Smaller than hemaphroditic female; labial papillae prominent.
2. Reproductive system amphidelphic, vulva not functional for
egg deposition, but functional for mating.
Fig. 12 (continued)
78
Laboratory Techniques for Entomopathogenic Nematodes