University of Michigan Biological Station

Biology 442 - Biology of Insects

Lecture Notes - Families of Hymenoptera

1. Symphyta (Sawflies). Abdomen broadly joined. Ovipositor looks like saw in some groups. Immatures look like caterpillars, but have more than 5 pairs of prolegs and only 1 pair of stemmata. Phytophagous and xylophagous.
   1. Cimbicidae.
      1. Size - medium to large.
      2. Diagnostic characters.
         1. 2 spurs on foretibiae.
         2. Clubbed antennae.
      3. Habitat. Woods or woodland edges.
      4. Food. Most feed on woody plants.
      5. Other. Tend to perch on branches and fly out.
   2. Tenthredinidae.
      1. Size - small to medium.
      2. Diagnostic characters.
         1. 2 spurs on foretibiae.
         2. Antennae not clubbed.
         3. Antennae 7-10 segments.
      3. Habitat. Various.
      4. Food. Foliage feeders on many plants. Some gallers.
      5. Other. Most abundant group of sawflies.
   3. Siricidae (horntails).
      1. Size - medium to large.
      2. Diagnostic characters.
         1. 1 spur on foretibiae.
         2. large horny plate at end of abdomen.
      3. Habitat. Woods.
      4. Food. Wood borers.
      5. Other. Parasitized by large ichneumonid.
   4. Xiphydriidae (wood wasps).
      1. Size - medium.
      2. Diagnostic characters.
         1. 1 spur on foretibiae.
         2. No large horny plate at end of abdomen.
         3. Have distinct neck.
      3. Habitat. Wooded areas.
      4. Food. Wood borers.
      5. Other. Not common.
2. Apocrita (wasps, bees, ants). Constricted 2nd segement of abdomen (propodeum is first segment, remainder called metasoma). Many parasitoids, predators and some plant feeders. Adults on flowers for nectar or pollen, sap, honeydew, other plant materials, some predaceous.
   1. Braconidae. 1900 spp.
      1. Size - small.
      2. Diagnostic characters.
         1. Long antennae.
         2. 2 seg. trochanters.
         3. No costal cell.
         4. 1 recurrent vein (m-cu crossvein).
      3. Habitat. All terrestrial habitats.
      4. Food. Parasitoids of all kinds.
      5. Other. Many are valuable as biocontrol agents. Exhibit hyperparasitism and polyembryony.
   2. Ichneumonidae. 3300 spp.
      1. Size - small to large.
      2. Diagnostic characters.
         1. Long antennae.
         2. 2 seg. trochanters.
         3. No costal cell.
         4. 2 recurrent veins.
      3. Habitat. All terrestrial habitats.
      4. Food. Parasitoids of many kinds.
      5. Other. Many are valuable as biocontrol agents. Largest family of hymenoptera. You will get sick of keying out ichneumonids.
   3. S. F. Chalcidoidea. Many families. 2200 spp.
      1. Size - minute to small.
      2. Diagnostic characters.
         1. Small size.
         2. Extremely reduced venation.
      3. Habitat. Many different terrestrial habitats.
      4. Food. Most are parasitoids of various kinds. Some phytophagous.
      5. Other. Extremely abundant. Many very important as biocontrol agents. Easy to get by sweeping vegetation.
   4. Cynipidae (gall wasps).
      1. Size - minute to small.
      2. Diagnostic characters.
         1. Small size.
         2. Characteristic reduced venation pattern.
      3. Habitat. Primarily wooded areas.
      4. Food. Primarily oaks. Some on roses. Some hyperparasites.
      5. Other. Very complex life cycles with asexual and sexual generations and very different appearances. Once common to have them described in different genera.
   5. Pelecinidae. 1 sp.
      1. Size - large.
      2. Diagnostic characters.
         1. Reduced venation.
         2. Very long abdomen.
      3. Habitat. Woods.
      4. Food. Parasites on June beetle larvae.
      5. Other. Nearly all females in this part of range. Have seen 1 male from station. Range extends to Central America.
   6. Chrysididae (cuckoo wasps).
      1. Size - small to medium.
      2. Diagnostic characters.
         1. Metallic green or blue.
         2. Hard, sculptured body.
         3. Abdomen hollowed out underneath.
      3. Habitat. Various terrestrial, but common in wooded areas.
      4. Food. Nest parasites of bees and wasps.
      5. Other. Female sneaks into nest when resident is gone and lays egg on prey provisioned by other species. Egg hatches first and kills other egg, then eats provisions. Hard exoskeleton and hollow abdomen allow to escape harm when caught by returning resident. Could confuse with some Chalcids, but less-reduced venation.
   7. Sphecidae. Large family.
      1. Size - small to large.
      2. Diagnostic characters.
         1. Pronotum with lobe that doesn't reach tegula.
         2. No branched hairs.
         3. 1st seg. of hindtarsus not expanded and flattened.
      3. Habitat. Many terrestrial habitats.
      4. Food. Females hunt for arthropod prey to provision nests.
      5. Other. Many nest in ground or cavities in wood. Includes mud daubers, bee wolves, cicada killers.
   8. Colletidae (white-faced bees).
      1. Size - small to medium.
      2. Diagnostic characters.
         1. Pronotal lobe not reaching tegula.
         2. Branched hairs.
         3. 1st seg. of hindtarsis expanded slightly.
         4. Long jugal lobe.
         5. 2 or 3 submarginal cells.
         6. Often with white face.
         7. Not very hairy.
         8. 2nd recurrent vien often sigmoid.
      3. Habitat. Terrestrial, often wooded.
      4. Food. Pollen, carried in crop.
      5. Other. All solitary.
   9. Halictidae.
      1. Size - small to medium.
      2. Diagnostic characters.
         1. Pronotal lobe not reaching tegula.
         2. Branched hairs.
         3. 1st seg. of hindtarsis expanded.
         4. Long jugal lobe.
         5. 3 submarginal cells.
         6. Often metalic.
         7. Strongly arched basal vein.
      3. Habitat. Various.
      4. Food. Pollen.
      5. Other. Most nest in the ground. Have a variety of social systems.
   10. Andrenidae.
       1. Size - medium.
       2. Diagnostic characters.
          1. Pronotal lobe not reaching tegula.
          2. Branched hairs.
          3. 1st seg. of hindtarsis expanded.
          4. Long jugal lobe.
          5. 2 or 3 submarginal cells.
          6. Basal vein not strongly arched.
          7. 2 sulci under antennae.
       3. Habitat. Various.
       4. Food. Pollen.
       5. Other. Ground nesters.
   11. Megachilidae (leaf-cutting bees).
       1. Size - medium to large.
       2. Diagnostic characters.
          1. Pronotal lobe not reaching tegula.
          2. Branched hairs.
          3. 1st seg. of hindtarsis expanded.
          4. Short jugal lobe.
          5. 2 submarginal cells.
       3. Habitat. Various.
       4. Food. Pollen carried on underside of abdomen.
       5. Other. Nest in natural cavities lined with leaf pieces.
   12. Anthophoridae (cuckoo bees and digger bees).
       1. Size - small to medium.
       2. Diagnostic characters.
          1. Pronotal lobe not reaching tegula.
          2. Branched hairs.
          3. 1st seg. of hindtarsis expanded.
          4. Short jugal lobe.
          5. 3 submarginal cells.
          6. Hindwing with jugal lobe and hindtibiae with spurs.
       3. Habitat. Various.
       4. Food. Pollen. Some nest parasites.
       5. Other. Parasitize other bees like cuckoo wasps. Others nest in ground or banks and line cells with wax or varnish-like substance. Parasites have fewer hairs.
   13. Apidae (bumble bees and honey bees).
       1. Size - medium to large.
       2. Diagnostic characters.
          1. Pronotal lobe not reaching tegula.
          2. Branched hairs.
          3. 1st seg. of hindtarsis expanded.
          4. Short jugal lobe.
          5. 3 submarginal cells.
          6. Hindwing lacks jugal lobe (bumble bees) or hindtibiae lack spurs (honey bees).
       3. Habitat. Various.
       4. Food. Pollen.
       5. Other. All are eusocial. Bumble bees nest in cavities in ground. Honey bees in hollow trees. Construct comb and store honey and rear brood. Have elaborate division of labor. Honey bees are not native species. Africanized honey bee problem for beekeepers.
   14. Tiphiidae.
       1. Size - medium to large.
       2. Diagnostic characters.
          1. 2 ventral plate extend over base of mid-coxae.
          2. Often with distinct abdominal segments.
       3. Habitat. Various. Often woods.
       4. Food. Parasites of scarab beetle larvae.
       5. Other.
   15. Mutillidae (velvet ants).
       1. Size - small to medium.
       2. Diagnostic characters.
          1. Dense pubescence
          2. Felt line on metasomatic tergum
          3. Female wingless, often red.
       3. Habitat. Various, but often sandy areas.
       4. Food. Parasites of ground nesting wasps and bees.
       5. Other. Female enters nest and lays egg. Has extremely hard body to avoid damage from returning resident. Some called cow-killers.
   16. Pompilidae (spider wasps).
       1. Size - medium to large.
       2. Diagnostic characters.
          1. Transverse suture on mesopleuron.
          2. Quadrate pronotum.
          3. Long legs.
          4. Usually dark with smoky wings.
       3. Habitat. Various, often sandy areas.
       4. Food. Spiders.
       5. Other. Sting prey to immobilize, then provision nest. Act like they are nervous, always flipping wings.
   17. Scoliidae.
       1. Size - large.
       2. Diagnostic characters.
          1. Large size.
          2. Black and yellow.
          3. 1 ventral plate covers base of meso and metacoxae.
       3. Habitat. Generally wooded.
       4. Food. Parasites of scarab beetle grubs.
       5. Other. Dig down and sting grubs, lay egg on grub in place.
   18. Vespidae (paper wasps, yellow jackets, hornets, mason wasps, potter wasps).
       1. Size - medium to large.
       2. Diagnostic characters.
          1. Pronotum u-shaped from top, with lobed reaching tegula.
          2. 1st median cell on forewing very long.
          3. Wings fold longitudinally at rest.
       3. Habitat. Various.
       4. Food. Vespinae and Polistinae - various insect prey. Eumeninae - mainly caterpillars.
       5. Other. Vespinae and Polistinae are eusocial and build paper nests. Paper wasps - open cells, hornets - cover cells, yellow jackets - build underground. Eumeninae are solitary.
   19. Formicidae (ants).
       1. Size - small to large.
       2. Diagnostic characters.
          1. Metasoma with pedicel with upright lobe - may be 1 or 2 segmented.
          2. Elbowed antennae.
          3. Often wingless.
       3. Habitat. Nearly all terrestrial habitats.
       4. Food. Variety of things. Some carnivores, some phytophagous, some nectar, honeydew, some fungi.
       5. Other. Many very interesting biologies. Army ants, leaf-cutting ants, slave makers, associations with aphids and caterpillars.

Lecture Notes Menu	Schedule	Course Description
Hymenoptera taxonomic sheet	Next lecture

Back to Top