File: <evani1.ima.htm> [For educational purposes only] Terminology Glossary <Principal Natural
Enemy Groups > <Citations> |
Immature Stages
of Evaniidae
Detailed information on immature stages of Evaniidae
is being acquired. However, Clausen
(1940) noted that the egg is cylindrical, 1.0 mm. long X 0.25 mm. In the greatest width, slightly curved,
and with one end clearly constricted and terminating in a broadly conical
structure which bears a minute pedicel. The 1st instar larva is slightly cylindrical with 13
distinct segments, simple but strongly extruded mandibles, and a complete
internal tracheal system, but no spiracles.
In this stage, feeding is confined to the contents of the single egg,
but following the first molt the neighboring eggs in the capsule are
attacked. In its first stage, the
larva is thus a true egg parasite, while it becomes an egg predator after the
molt. The 2nd instar larva is
globular in form but otherwise closely resembles the preceding instar, the
distinguishing characters being those of the head. The 3rd and last instar larva is very robust, ca. 2X as long as
wide, with the head large and the mandibles still simple. There are no integumentary spines, sensory
setae, or sculpturing upon the body.
The tracheal system is open, with 9 pairs of spiracles located on the
1st and 3rd thoracic and the 1st 7 abdominal segments. In addition to the usual anterior and
posterior commissures, each of the 7 abdominal segments possesses an
accessory ventral commissure. References: Please refer to <biology.ref.htm>,
[Additional references may be
found at: MELVYL Library ] |