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Paper Wasp - Polistes annularis
Wasps that construct nests made of a papery material are
commonly called paper wasps. The nests consist of a single
upside-down layer of brood cells.
Live adult Strepsiptera infected Polistes paper wasps photographed in the wild at Vero Beach, Florida, USA.
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Paper wasp Polistes annularis with paper
brood cells. Single eggs are visible at the bottom
of each hexagonal cell. |
Wasps that construct
nests made of a papery material are commonly called paper wasps. The
nests consist of a single upside-down layer of brood cells. There
are 22 species of paper wasps in North America and about 700 species
world-wide. Most are resident in the tropics of the western
hemisphere. The two most common paper wasps in the American midwest
are Polistes dominulus, an introduced species, and Poliste fuscatus,
the native "golden paper wasp." It is my opinion, after 5 years of
careful field work and observance, that dominulus is replacing
fuscatus, at least in the environs of DuPage County, Illinois.
Most paper wasps measure about 2 cm (0.75 in) long and are black,
brown, or reddish in color with yellow markings. Paper wasps will
defend their nest if attacked. Adults forage for nectar, their
source of energy, and for caterpillars to feed the larvae (young).
They are natural enemies of many garden insect pests.
Paper wasp building brood cells
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The nests of most species are suspended
from a single, central stalk, or
pedicle, and have the shape of an
upside-down umbrella. Some tropical
species make nests that hang in a
vertical sheet of cells. Plant and wood
fibers are collected by the wasps, mixed
with saliva, and chewed into a
paper-like material that is formed into
the thin cells of the nest. The nests
are constructed in protected places,
such as under the eaves of buildings or
in dense vegetation.
The colony is founded in early spring, soon after the queens emerge
from hibernation. As the colony matures, males and the next year's
queens are produced. These queens mate with males and are the only
members of the colony to survive through winter. In late summer or
fall, the founding queen, workers (sterile females), and males all
die. The newly mated queens hibernate, in piles of wood, in
vegetation, or in holes. The following spring they emerge and begin
the cycle anew. A similar life cycle is found in bumble bees.
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| The anterior abdomens of three female
Strepsiptera in the family Stylopidae protrude from
under the abdominal segments of a paper wasp in the genus
Polistes. Female
Strepsiptera thus provide access to adult
males for purposes of reproduction, which is accomplished by
a process known as hypodermic insemination. In this
instance, the insects are acting as endoparasites, that is,
living inside the host's body. |
Commonly called twisted wing
parasites, these insects are mostly
internal parasites of other insects.
Males differ greatly from females in
structure. Males have wide heads with
compound eyes on the sides. Males also
have fan shaped antennae. Their
forewings have evolved into clublike
structures and the hind wings are
membranous and with out venation.
Females are without legs, wings,
antennae and often eye and remain in the
host their entire lives. The females
remain in the host with only their heads
protruding. Males leave the host and
find females to mate with. The newly
hatched, well-developed larvae leave the
female and fall from the host to the
ground or to plants.
Twistedwing parasites enter their insect
hosts as larva through joints or sutures
when the host itself is still in its
larval stage. From there they undergo
what is called "hypermetamorphosis":
They molt into another, less mobile,
larval form and feed in the host's body
cavity. From there they undergo
holometabolous metamorphosis. Hosts are
not usually killed by infection but may
be injured. The shape and color of the
abdomen may be changed and the sex
organs of the host may be damaged. The
male usually causes more damage to the
host than the female. Common hosts are
various species from the orders
Orthoptera, Hemiptera, Hymenoptera and
Thysanura.
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