2. Pick up the desired specimens by “nematode pick” under a
dissecting microscope.
3. Place the specimen in the fixative at the midpoint of the glass
slide.
4. Keep the glass slide below the dissecting microscope.
5. Position the nematodes at the midpoint of the slide at the
bottom of the drop.
6. Set glass wool in a triangular shape around the perimeter of
the drop.
7. Keep a cover glass smoothly over the drop by means of forceps
or by needle support.
8. Remove attentively excess fixative with filter paper.
9. Smear nail polish with a tiny brush to the verge of the cover
glass, to secure it.
10. Observe the slides under a phase contrast microscope after the
sealant has dried.
Nematode Stages
(a) Third-stage infective juveniles—recovered upon emergence
from the cadavers 8–11 days after the G. mellonella larvae
is dead.
(b) Adult: Male, female—collected by dissecting the cadavers
(infected last instar G. mellonella larvae) 2–4 days and 5–7
days, respectively, after the death of insects.
(c) A minimum of 25 specimens of infective juveniles and
25 males of the first generation is collected for morphological
and morphometric studies of each species.
4.1.3 Diagnostic
Characters [62]
Family Steinernematidae
Diagnosis
Strongyloidoidea, Rhabditida. Obligate insect parasites. Infective
juveniles are infested with symbiotic bacteria in the bacterial chamber of their intestine. The process of reproduction requires both
males and females.
Female
1. They are huge, variable in size. They have smooth cuticle or
annulated without lateral fields.
2. Distinct excretory pore are seen.
3. Spherical head or truncate, rarely offset. They have entirely
fused or parted six lips present, each lip comprises one labial
papilla, and occasionally additional papilla-like structures are
seen near labial papillae.
4. Four cephalic papillae. Small amphids are seen. The stoma is
usually collapsed; and distinct cheilorhabdions are witnessed,
forming a ring resembling two large sclerotized dots in
lateral view.
Morphological Characterization
73
dissecting microscope.
3. Place the specimen in the fixative at the midpoint of the glass
slide.
4. Keep the glass slide below the dissecting microscope.
5. Position the nematodes at the midpoint of the slide at the
bottom of the drop.
6. Set glass wool in a triangular shape around the perimeter of
the drop.
7. Keep a cover glass smoothly over the drop by means of forceps
or by needle support.
8. Remove attentively excess fixative with filter paper.
9. Smear nail polish with a tiny brush to the verge of the cover
glass, to secure it.
10. Observe the slides under a phase contrast microscope after the
sealant has dried.
Nematode Stages
(a) Third-stage infective juveniles—recovered upon emergence
from the cadavers 8–11 days after the G. mellonella larvae
is dead.
(b) Adult: Male, female—collected by dissecting the cadavers
(infected last instar G. mellonella larvae) 2–4 days and 5–7
days, respectively, after the death of insects.
(c) A minimum of 25 specimens of infective juveniles and
25 males of the first generation is collected for morphological
and morphometric studies of each species.
4.1.3 Diagnostic
Characters [62]
Family Steinernematidae
Diagnosis
Strongyloidoidea, Rhabditida. Obligate insect parasites. Infective
juveniles are infested with symbiotic bacteria in the bacterial chamber of their intestine. The process of reproduction requires both
males and females.
Female
1. They are huge, variable in size. They have smooth cuticle or
annulated without lateral fields.
2. Distinct excretory pore are seen.
3. Spherical head or truncate, rarely offset. They have entirely
fused or parted six lips present, each lip comprises one labial
papilla, and occasionally additional papilla-like structures are
seen near labial papillae.
4. Four cephalic papillae. Small amphids are seen. The stoma is
usually collapsed; and distinct cheilorhabdions are witnessed,
forming a ring resembling two large sclerotized dots in
lateral view.
Morphological Characterization
73