the north face jackets kids Auburn University Entomology and Plant Pathology
Caterpillars are larvae (the forms) of insects in the order Lepidopterathe butterflies, skippers, and moths. In number of species known, Lepidoptera is the second largest of all insect orders. Consequently, caterpillars are numerous; more than 11,000 species occur in North America, with over 5,000 species in the eastern United States alone. Most caterpillars are plant feeders. They occur on a wide variety of plants, and many are serious pests. Caterpillars are among the most common of all insect forms found on foliage of forest, shade, and ornamental trees.
The typical caterpillar has a distinct head and a cylindrical body composed of thirteen segments. The anterior three body segments constitute the thorax, and each thoracic segment bears a pair of jointed legs. The remaining ten segments make up the abdomen. Typically, abdominal segments three, four, five, six, and ten each bears a pair of unjointed, fleshy projections called prolegs. In some caterpillar groups, however, prolegs may be absent (slug caterpillars) or occur only on segments five, six, and ten or six and ten (loopers). Prolegs are equipped with rows or circles of small hooks called crochets which aid caterpillars in crawling and clinging to surfaces.
Caterpillars come in a variety of shapes, colors, and sizes. Some species are bare, others sparsely to densely clothed with fine setae (hairs); some are drab, others brightly multicolored; some have smooth bodies, others bear one to many tubercles, bristles, spines, and/or horn like projections. Within the group are found some of the largest and most striking representatives of our native insects. Also, within the group are found CATERPILLARS THAT caterpillars do not sting in the familiar manner of bees, yellowjackets, hornets, and wasps (Order Hymenoptera). In the bee wasp group, females (only females sting) are equipped with venom glands and stingers (modified ovipositors) with which they penetrate skin and introduce venom. Among the lepidopterans, neither the adult nor the caterpillar possesses this type of sting apparatus. Instead, stinging caterpillars bear specialized nettling or urticaceous setae or spines. These structures are hollow and contain toxins from poison gland cells to which they are joined. These are primarily defensive structures for protection of caterpillars from predators and other enemies. The sting inflicted on humans is not from a deliberate attack by the caterpillar, but the result of contact, usually inadvertent, with toxin bearing setae or spines. When brushed against, these structures break away, releasing toxins. In some cases, broken setae may penetrate the skin; in others, toxins spill out to spread on the surface of the skin.
Reactions to contact vary and include: slight to intense nettling, stinging, itching, or burning sensations; development of dermatitis, rash, lesions, or pustules; inflammation, swelling, and numbness at or around the area of contact; fever and nausea; and, in some cases, intense pain. The type of reaction depends on the species of caterpillar, degree of contact, type of toxin, and susceptibility of the individual. Reactions may be especially severe for individuals with allergies or sensitive skin.
The irritation usually results from direct contact with a live caterpillar. However, in some species, urticating setae may retain nettling capabilities for some time after death of the caterpillar. Molted skins and silk cocoons bearing toxic hairs from last stage larvae may also cause nettling if handled. Nettling caused by contact with dead caterpillars, cast skins, and cocoons is generally milder than that produced by live caterpillars.
Many species of caterpillars are variously armed or clothed with setae and spines; however, only a relative few actually possess venomous or urticating structures. Thus, there are and harmless and distinguishing one from the other solely on appearance is difficult. Determining which is which by personal bio assay is foolproof but could be foolhardy and painful.
During years of study of tree insects at the Alabama Agricultural Experiment Station, several species of urticating caterpillars have been encountered and identified. Represented are nine families that contain one or more species known, or reported, to be urticaceous or otherwise capable of causing irritating reactions on contact with human skin. The following is offered as a guide to recognition of stinging caterpillars found on Alabama trees. The head is hidden within the thorax; thoracic legs are reduced; and prolegs are modified to sucker like lobes without crochets. Movement is slow, gliding, slug like. Most species tend to be solitary feeders, and seldom occur in sufficient abundance to cause serious loss of tree foliage. Several species of slug caterpillars possess urticating setae or spines. Its conspicuous form and markings make it nearly unmistakable, even in the early stages of development. The full grown caterpillar is about 1 inch long. The anterior and posterior areas of the body are dark brown with prominent brown that bear numerous spines. The middle of the body is green. The green area has a white or cream margin and a large oval to oblong dark brown spot in the center, also with white margin. The appearance is that of a saddle and blanket, thus the common name. Small clumps of spines occur in a row along the lower margin of the green area and at the rear of the caterpillar.
The saddleback is generally a solitary feeder; however, early stage larvae may be somewhat gregarious. The caterpillar occurs on a wide variety of trees, shrubs, and other plants, including corn. Common tree hosts are apple, basswood, cherry, dogwood, elm, maple, oak, and plum. It is most often encountered in late summer and fall. The full grown caterpillar is brown, hairy, and about5/8inch long. Along the body there are nine pairs of fleshy lateral processes which bear hidden urticating setae. The third, fifth, and seventh pairs of processes are long and sometimes twisted. These have been described as resembling locks of a hag apparently the basis for the common name.
The caterpillar is generally a solitary feeder, and will feed on foliage of several trees including apple, ash, birch, dogwood, hickory, oak, and willow. It has been collected from July into fall, but is usually most common in August and September. The body bears pairs of long, horn like, bristly spines and clumps of smaller spines which are characteristic of several of the slug caterpillars. A useful identifying characteristic is the broad purplish band down the midline of the back. Within the band are narrow whitish longitudinal lines, which may be interrupted by constrictions in the band. Reddish, white, and purple lines occur along the sides.
Hosts of the stinging rose caterpillar include apple, cottonwood, dogwood, hickory, oak, redbud, sycamore and rose bushes. Larvae are usually found in August. Specimens have been collected in Lee County from cottonwood and oak at the end of August.
SpinyOak Slug (Euclea delphinii) (Photo 4)
The full grown larva is about3/4inch long. Basic color is yellow green but color, especially of the pattern on the back, may vary. There are three pairs of large horn like spines with black tipped bristles at the front and two pairs at the rear. Clumps of smaller spines occur in rows along the back and sides. There are four dense clumps of small dark spines at the rear end; these are important characteristics for identifying the species.
The caterpillar feeds on foliage of several woody plants including beech, cherry, maple, oak, redbud, sycamore, and willow. It is usually found in late summer and fall. The specimen pictured here was collected from redbud in late September.
This species has no known common name. Information available on its habits is limited and makes no reference to whether or not the species has stinging capabilities. However, being a slug caterpillar well equipped with bristled spines, it seems suspect.
on experience has now confirmed that I. textula is a LLH.
The full grown caterpillar is flattened and about5/8inch long. Color and markings are as pictured. Tree hosts include cherry, maple, and oak. The species is not common in our area. The specimen pictured was collected in Lee County from sawtooth oak in mid September.
Nason (Natada nasoni)1(Photo 6)
The form of Nason slug differs from that of the foregoing slugs in that there are no large, conspicuous, horn like bristled spines present. There are, however, rows or tufts of small spines, some of which are urticating, along the back and sides. The nettling sensation produced is mild and short lived.
The full grown caterpillar is3/4to7/8inch long. Basic color is green; markings are as pictured. Food trees include beech, hickory, hornbeam, oak, and several other trees and shrubs. This caterpillar is not common in our area. The specimen pictured here was collected in Lee County from sawtooth oak in early October.