Heterorhabditis brevicaudis

Liu, 1994

DESCRIPTION

Females: Size variable. Cuticle smooth, head truncated or slightly rounded. Six distinct lips, each lip with a single labial papilla, at the base of each lip; a single cephalic papilla located at the base of each lip. Two amphids located at the base of lateral lips. Cheilorhabdions, present as a refractile ring in anterior portion of stoma, other portion of stoma collapsed, funnel-shaped. Procorpus of esophagus cylindrical, median bulb slightly swollen, isthmus present, basal bulb expanding with indistinct valve. Nerve ring distinct, around isthmus. Intestine separated from esophagus by a pair of cell membrane, (valve). The excretory pore usually located anteriorly to basal bulb, sometimes posteriorly to basal bulb. Gonads paired, reflexed. Hermaphrodite of the first generation adult has sperms at the growth zone of the ovary. The second generation bisexual female has sperms stored in the oviduct. Vulva located in midbody region with slightly protruding lips. Tail pointed, usually with a postanal or anal swelling.

Males:Smaller than females, more transparent, spicule paired, slightly curved, tips pointed. Head of spicules rounded. Spicule with a rib which is bifurcate at tip. Gubernaculum about half the spicule length, bursa with 9 pairs of papillae, 3 pairs anterior to cloaca opening, and 6 pairs posterior (FIG.1).

 Infective juveniles: in J2 cuticle, with distinct longitudinal ridges. Stoma and anal opening closed. Esophagus narrow and long. Intestine usually indistinct.. Tail short, sharply pointed.

Measurements: (in micrometers)

Hermaphroditic females (n=20): L=4330 (3550-5040 ), W= 25(200-312); stoma length = 10.4 (8.8-12) ; stoma width = 18.2 (16.20); head-excretory pore = 190 (160-200) ; head-nerve ring = 164.4 (144-176) ; esophagus length = 218 (192-240) ; tail length = 86(72-128); ABW = 70.4 (56-88); V%=43.2(37-50).

Amphimictic females (n=20): L=2350 (2100-2500); W = 149 (128-168); stoma length = 6 (6-6); stoma width = 10(10-10 ); head excretory pore = 135 (124-160); head-nerve ring = 103 (100-108); esophagus length = 154(144-160); tail length = 86(76-92); ABW = 39(36-48); V%=48.4(45-53).

 Males (n=20): L = 900 (840-950) ; W=42.6 (40-48) ; stoma length = 1.9 (1.2-2); stoma width = 3.98(3.2-4.8); head-excretory pore = 95 (92-100); head-nerve ring = 82.4 (80-88); esophagus length = 108 (104-112) ; tail length = 32 (28-36) ; gonad reflexion = 193.6 (162-240); ABW = 19.7 (16-22); spicule length = 46.8 (44.48); spicule width = 6.6 (6-8); gubernaculum length = 22.2 (20-24). gubernaculum width =3.8 (3.2-4).

 Infective juveniles (n--20): L--572(528-632); W=2 2 (2 0-2 4) ; head-excretory pore = 111 (1. 4-116) ; head-nerve ring=101 (96-104) ; esophagus length = 124 (120-136) ; tail = 75.5 (68-80) ; ABW = 8.8 (8-12); c=7.6(6.6-8.6); E=1.6(1.5-1.8)

TYPE HOST AND LOCALITY:

The new species was isolated from Changle county, Fujian province. The type host unknown. The nematodes were reared in larvae of Galleria mellonella.

(This species was placed in species inquirenda)

REFERENCE

Liu, J. 1994. A new species of the genus Heterorhabditis from China (Rhabditida:
Heterorhabditidae). Acta Zootaxonomica Sinica 19:268-272.


This document was constructed and is maintained by KHUONG B. NGUYEN
Entomology & Nematology Department
University of Florida