DESCRIPTION
Females: Head truncate or
slightly rounded. Labial region with six distinct protruding lips surrounding
the mouth with six labial papillae on tops. Amphids located posterior to
labial papillae (FIG.1)
. Under a compound microscope, cheilorhabdions seen as lightly refractile
areas lining anterior (non-collapsed) portion of stoma; metarhabdions
right posterior to cheilorhabdions attached to fused pro- and mesorhabdions,
each metarhabdial segment bears a small tooth; telorhabdions absent; a
reduced colla is present. Basal bulb often surrounded by anterior
portion of intestine. Nerve ring surrounding isthmus just anterior
to basal bulb. Excretory pore usually posterior to the basal bulb. Intestine
with few large cells. Lateral fields not seen, phasmids inconspicuous.
Vullva near mid-body. Gonads amphidelphic, reflexed. Hermaphroditic
female with vulva open, protruding outward and functional for oviposition
. Tail pointed.
Females of bisexual generation
similar
to hermaphroditic females but different in head and vulva region:
head subconical, lip region often faintly set off from remainder of head;
vulva non-functional for oviposition, often covered with a hardened deposit.
The vulva appears to be nonfunctional after mating and does not protrude
outward, often surrounded by a hardened deposit. Anal region slightly protruding.
Measurements:All measurements are
in micrometers (um).
Hermaphroditic females (n - 15): L: 4030 (3630-4390) ; greatest
width: 165 (160-180) ; length of stoma: 8 (6-9) ; width of stoma: 8 (6-9);
distance from head to nerve ring: 126 (121-130); distance from head to
excretory pore: 209 (189-217); length of esophagus: 197 (189-205); V: 44
.(4.1-47) % from head; length of tail: 90 (81-93); body width at anus:
46 (40-5 3) .
Amphimictic females (n - 15): L: 3500 (3180-3850) ; greatest
width: 190 (160-220); length of stoma: 7 (6-9); width of stoma: 7 (6-9);
distance from head to nerve ring: 103 (93-118); distance from head to excretory
pore: 192 (174-214); length of pharynx: 168 (155-183); V: 47 (42-53) go'.
length of tail: 82 (71-93); body width at anus: 28 (22-31).
Males: Anterior region similar to female, but smaller. Testis single, reflexed leading into a seminal vesicle containing sperm cells; vas deferens well developed. Spicules paired and separate; shape of capitulum variable, from pointed to flat. Gubernaculum with the proximal portion curving ventrally between the spicules. Bursa peloderan, open, supported normally by nine pairs of papillae (FIG.2): a small anterior pair, two pair adjacent to the spicules and six pairs distal to the anal opening. The latter six are in two sets of threes; rarely, the terminal group may consist of only two or even four papillae. More frequently, one or two of the three may be branched. Papillae pairs 4, 7, 8 and 9 do not reach the rim of the bursa.
Measurements:
Males (n - 15): L: 820 (780-960); greatest width: 43 (38-46);
length of stoma: 3 (2-4); width of stoma: 2 (1-3); distance from head to
nerve ring: 72 (65-81); distance from head to excretory pore: 121 (114-130);
length of pharynx: 103 (99-105); reflexion of testis: 79 (59-87); length
of tail: 28 (22-36); width of body at anus: 23 (22-25); spicules paired,
separate, equal; length: 40 (36-44); gubernaculum length: 20 (18-25).
Infective stage juveniles: Mouth and anus closed; pharynx and intestine collapsed; tail pointed; cuticle with longitudinal striae; cells of a rod-shaped bacterium occur in the ventricular portion of the intestine; body initially covered with the enclosing 2nd stage cuticle, which is lost soon after the juveniles leave the host cadaver.
Measurements:
Infective juveniles (n = 15): L: 570 (520-600); greatest width:
24 (21-31); distance from head to nerve ring: 83 (81-88); distance from
head to excretory pore: 104 (94-109); length of esophagus: 125 (119-130);
length of tail: 91 (83-99).
TYPE HOST AND HABITAT: In the body cavity of Heliolhis punctigera Hall (Noctuidae: Lepidoptera).
TYPE LOCALITY: Brecon, South Australia.
TYPE SPECIMENS: Holotype (hermaphroditic female), allotype (male) and paratype (amphimictic female) deposited in the nematology collection at the University of California at Davis, Calif., U.S.A.
REFERENCES
Poinar, G. O., Jr. 1976. Description and
biology of a new insect parasitic rhabditoid, Heterorhabditis bacteriophora
n. gen. n. sp. (Rhabditida; Heterorhabditidae n. fam.).
Nematologica 21:463-470.
This document was constructed and is maintained by KHUONG
B. NGUYEN
Entomology & Nematology Department
University of Florida