Review Sheet -- Test 2 (Week 8/9) Biology 1224 -- Entomology; James Adams
Infraclass Neoptera; Division Endopterygota
Superorder Hymenopteroidea: Chapter 16, page 341; Chapter 41
One order is included in this superorder -- the Hymenoptera. Considered to be quite
distinct from all other endopterygotes: they have numerous Malpighian Tubules (unlike the 4 to 6
in all other endopterygotes); wing venation is very different, with lots of fusions and several large
cells. They are probably most closely related to the Mecopteroids, as there are several
hymenopteran families that have caterpillar-like larvae similar to the Mecoptera and Lepidoptera,
and some also have pupae enclosed in a cocoon.
Order Hymenoptera ("membrane-winged")
-The Bees, Wasps, Ants, Sawflies, etc. (Chapter 41)
Minute to large insects, usually with membranous wings, though many ants wingless.
Head
typically hypognathous, with mandibles adapted for chewing; labium often elongated
(sometimes
extremely) and aids in drinking (nectar); antennae typically obvious and sometimes
quite long and
filiform. Prothorax small and collarlike, though larger in ambulatory species (ants);
mesothorax large
and fused with smaller metathorax; wings membranous, almost always with
clear areas and with
several cells; veins often fused/reduced in number, and small species with
small wings often nearly
veinless; wing coupling by hamuli (hooked setae on leading edge of
hindwings). Primitive families
(Symphyta) with abdomen relatively unmodified; in more advanced
families, abdomen with first
segment (propodeum) fused to metathorax; second segment typically
narrowed into a petiole
(stem) for increased flexibility; rest of abdomen enlarged. Females
typically with slicing or piercing
ovipositor for laying eggs in plant stems or in animal tissues
(larvae); modified into a stinger in many
advanced families (males DON'T sting). The stinger
venomizes prey for immobilization, but may be
used in defense against vertebrate predators,
particularly in social species, and the venom produces
significant pain in vertebrates. As such,
many species are warningly colored.
Larva very caterpillar like, with several pairs of abdominal prolegs, in free-living forms;
more
grublike or maggotlike in internal plant feeding and in nest-building (caregiving) species,
such as in
the Apocrita. Larvae of Apocrita do not have the midgut connected to the hindgut;
they are fed by
adults a very nutritious soup that is mostly absorbed; avoids contamination of the
nest with fecal
matter; the gut completes development in the last larval instar, and the gut is
voided before pupation.
In parasitoid species, first instar is often well developed, but head
capsule and legs become reduced
after infesting host. Pupa is adecticious, but usually exarate,
often enclosed in a cocoon.
Mating may be in the air, or on some surface, frequently where the females are visiting for
food.
In social species, females (queens) can often control the sex of the offspring by storing
sperm in her
spermatheca, and may be able to make sterile stinging females
(workers in social
species) and
haploid males for
when mating is necessary to produce another generation. A few
species of wasps
are entirely
parthenogenetic, exclusively producing females.
The Hymenoptera includes a lot of beneficial species, such as pollinators and predators on
a
number of herbivorous insects. Additionally, a number of species are parasitoids on larvae of a
huge
number of species in different orders, including some very obnoxious hymenopteran species
as well
(such as Fire Ants). Some species are even hyperparasitoids. As such, these species
have been
used for biological control. The Honeybee is useful not only as a pollinator, but for its
honey and wax.
There are some damaging species (gall wasps, sawflies) and nuisance species
(stinging species of bees,
wasps, ants), though beneficial species outnumber destructive ones.
Many species are social, though there are a lot of solitary nest builders as well.
Number of named Hymenoptera currently
<200,000, but the
undescribed small parasitoid
species of Hymenoptera may bring the number of Hymenoptera in excess of
400,000 or even
500,000 species, rivalling or even exceeding beetle species
numbers.
"Symphytan" superfamilies --
Abdomen not narrowed at thorax.
Likely encountered
families in this group include:
Tenthredinoidea: Tenthredinidae,
Cimbicidae, Diprionidae (and others): Sawflies
Siricoidea: *Siricidae: Horntails
"Apocritan" superfamilies --
Abdomen distinctly narrowed at thorax, having the
appearance of a "waist".
Likely encountered families in the Apocrita include:
Ichneumonoidea: *Ichneumonidae: Ichneumon Wasps; parasitoids,
typically with long
ovipositors.
Braconidae: Smaller but similar to Ichneumons
Evanoidea: Evaniidae: Evaniid or Ensign wasps;
larvae parasites on cockroach oothecae.
Gasteruptiidae: Adults on flowers, larvae parasites on other wasp larvae.
Cynipoidea: Cynipidae: Gall wasps and others; produce fuzzy galls.
Chalcidoidea: Chalcididae: Chalcidid wasps; small parasites, often with bizarre
leg shape
Leucospidae: Larger than preceding; parasites resembling small yellow jackets
Pteromalidae: Small, but commonest of the chalcidoid families
Chrysidoidea: *Chrysididae: Cuckoo Wasps; relatively small but
stunningly colored
insects; parasites on other wasps and bees; females do not sting, but roll into
a ball
when held.
Vespoidea: Tiphiidae: Tiphiid wasps; often large with elongated, striped, hairy abdomen
Scoliidae: Similar to tephiids; our commonest is black with orange abdominal end
*Mutilidae: Velvet Ants; also hairy; wingless females; stinger is extremely long
Pompiliidae: Spider Wasps; sometimes very large (such as the Tarantula Hawk)
*Formicidae: Ants
*Vespidae: Potter Wasps, Yellow Jackets, Hornets, Paper Wasps and others; some
of the most familiar wasps; some are social
Apoidea: *Sphecidae: Mud Daubers, Thread-waisted Wasps, Sand Wasps,
and others;
all species solitary; many elongate species but some much more stout
(All the remaining families are bees: "Anthophila")
Colletidae: Yellow Faced and Plasterer Bees; typically with light colored
fuzzy frons
Andrenidae:
robust bees; dark-striped or darkish colored bees
*Halictidae: Many dark colored, but small gold or green bees are these.
*Megachilidae: Leaf Cutter Bees; robust bees; hold wings out while visiting flowers;
carry pollen on underside of abdomen; use ground up leaves to nourish larvae
*Apidae: Carpenter Bees, Bumblebees, Honeybees
(includes the former family
Anthophoridae
which includes Digger Bees and Cuckoo Bees; Diggers are large and
robust, ground dwelling bees; Cuckoos lay eggs in other hymenopteran nests,
and
larvae eat the other
species brood).
As is the case within the Diptera
(yet to be discussed), be aware that there are a number of
other families that
contain minute species, so small that some lay eggs inside eggs of other small
hymenopterans.