Sawflies, Wasps, Bees, and Ants (Order Hymenoptera)

Adult hymenopterans possess four wings, with the hindwings smaller than the forewings. Except for the Sawflies, hymenopterans also have a constricted "waist" between the first and second abdominal segments and, in females, an ovipositor modified into a stinger. The larvae of Sawflies are mainly herbivorous and greatly resemble lepidopteran caterpillars. The wasps are mainly predaceous or parasitic on other insects and are very important in controlling their numbers. Some wasps and Sawflies parasitize plants by laying their eggs in plant tissues. The egg or resulting larvae then induces the plant to form a gall, which surrounds the insect. These galls are particularly common on oaks and willows. The bees feed primarily on pollen and nectar and are probably the most important agents of flower pollination.

Many hymenopterans live in tightly coordinated social groups usually dominated by one or more reproductive "queens." The queen's efforts at reproduction are aided by numerous "workers," which may be temporarily or permanently sterile. Ants represent the extreme of this type of social evolution, and the sterile, wingless workers are among the most common, visible insects in many habitats. They feed on small insects and obtain sugary "honeydew" secretions from Homoptera. They are very important in controlling the numbers of other insects in many habitats.

Sawflies,Tenthredospp. (Family Tenthredinidae). (Fig. 7.28) Adult Sawflies resemble wasps, except that they have a stout "waist" instead of the threadlike waist of the true wasps and bees. Sawflies are commonly encountered as larvae feeding on the leaves of plants. Many Sawfly larvae look very much like caterpillars of Lepidoptera,

Figure 7.28
Sawfly (Tenthredo  sp.).

Figure 7.29
Ichneumon (Ophion  sp.).

except that they possess prolegs on every abdominal segment rather than on five or fewer segments (as seen in Lepidoptera). Many Sawflies lay their eggs internally in the host plant leaves rather than externally, as in most Lepidoptera. Some Sawflies make galls in their host plants. Sawflies occur as high as Crooked Creek in the White Mountains (10,150 ft, 3,100 m).

Ichneumons,Ophionspp. (Family Ichneumonidae). (Fig. 7.29) Ichneumons are elongated wasps, the larvae of which are parasitic on other insects. They are frequently seen searching vegetation for their hosts by quivering their long, curled antennae and making short flights between branches or plants. They occur at all elevations below 13,000 ft (4,000 m).

Cuckoo Wasps,Chrysisspp. (Family Chrysididae). Cuckoo Wasps are brillant green and reproduce by parasitizing larvae of other wasps in their burrows. They occur at all elevations below 13,000 ft (4,000 m), where they may be seen drinking from flowers.

Tarantula Hawks,Pepsisspp. (Family Pompilidae). (Plate 7.1) Easily recognized wasps because of their very large size and black and orange wings, they occur from 4,000 to 8,000 ft (1,200 to 2,400 m) in summer and fall. These and other spider wasps actively hunt spiders, which they paralyze by stinging and drag to a burrow. Then they deposit an egg and seal up the burrow. Eventually the egg hatches, and the wasp larva consumes the spider. Smaller spider wasps in the same family occur at elevations up to 13,000 ft (4,000 m).

Resin Bees,Dianthidiumspp. (Family Megachilidae). (Fig. 7.30) Occur at elevations below 8,000 ft (2,400 m), and possibly higher. Commonly found in deserts and foothills in California, they nest alone rather than in colonies. Resin Bees are common pollinators of Phacelia and other desert flowers.

Figure 7.30
Resin Bee (Anthidium  sp.).

Figure 7.31
Honey Bee (Apis mellifera ).

Bumble Bees,Bombus centralisandB. morrisoni(Family Apidae). (Plate 7.1) Bumble bees occur at elevations up to 11,000 ft (3,400 m). Commonly seen visiting flowers, these bees live in nests underground.

Honey Bee,Apis mellifera(Family Apidae). (Fig. 7.31) Abundant at lower elevations, an introduced bee that has established itself in the wild, nesting in hollows in trees, caves, and underground.

Carpenter Bee,Xylocopa californica arizonensis(Family Anthophoridae). (Fig. 7.32) Adults are large, black bees that bore into dead wood to make nest chambers. They occur between 6,000 and 8,000 ft (1,800 and 2,400 m).

Ants (Family Formicidae). Ants are familiar organisms at all elevations in the White Mountains. Protected underground and by numerous worker individuals willing to sacrifice their lives in defense of the colony, ants are among the most successful creatures on earth. Perhaps because of the ants' abundance, many insects have evolved specific adaptations to survive with them. For example, aphids and many butterflies of the Family Lycaenidae secrete sugary honeydew, which attracts ants, which in return protect the insects from enemies such as parasitic wasps and Ladybird Beetles.

Figure 7.32
Carpenter Bee (Xylocopa  sp.).

Figure 7.33
Mound Ant (Formica  sp.).

Figure 7.34
Carpenter Ant (Camponotus  sp.).

Mound Ants, Formica spp. (Fig. 7.33) Occur from the Owens Valley to 12,500 ft (3,800 m) in large, mound-shaped nests on bare ground. These ants may be very aggressive. The species F. subpolita occurs at Barcroft Laboratory at 12,500 ft (3,800 m).

Carpenter ants, Camponotus spp. (Fig. 7.34) Large, black ants that usually nest in or near dead wood, which they hollow out. In spite of their large size, these ants are commonly timid and nonaggressive. They occur in dead wood to 11,000 ft (3,400 m). C. sansabeanus and C. ochreatus nest in dry wood near Westgard Pass.