Pauropods: Pauropoda

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PAUROPODS: Pauropoda

NO COMMON NAME (Allopauropus carolinensis): SPECIES ACCOUNT

PHYSICAL CHARACTERISTICS

Pauropods are very small, measuring only 0.019 to 0.078 inches (0.5 to 2.0 millimeters) in length. Their long slender white or brownish bodies are usually soft and flexible, but some are covered with relatively thick plates. The small head is directed downward. Their chewing mouthparts are small, weak, and made up of two sets of jaws. The first set of jaws has curved teeth that look like a comb. The second pair is joined together to form a flaplike structure. They lack eyes. The antennae (an-TEH-nee), or sense organs, have two branches. The body is twelve-segmented and has eight to eleven pairs of legs, one pair per body segment. There are usually only six plates across their backs, but some species have twelve. Like millipedes, the reproductive organs are located toward the front of the body on the third segment. The last segment has a special plate. The size and texture of the plate is used to distinguish different species.

GEOGRAPHIC RANGE

They are found on all continents except Antarctica. There are about seven hundred species known worldwide. The pauropods of the United States and Canada are so poorly known that it is not possible to give even an approximate number of species found in these countries.

HABITAT

Pauropods live in a variety of habitats and are most common in the upper 7.8 inches (200 millimeters) of soil. They are often found in moist soils under rocks, wood, and clumps of moss.

DIET

The foods of most pauropods are unknown. Some species eat mold or suck fluids from the rootlike structures of funguses. One species is known to eat the tiny hairlike structures on plant roots.

BEHAVIOR AND REPRODUCTION

Populations of pauropods are usually small and widely scattered, but the populations of some species can reach the thousands in both wild areas and agricultural fields. They move through the soil to follow changing moisture levels. Since their bodies are soft and not built for burrowing, pauropods follow roots and crevices deep into the soil as they search for moisture. Most species run very quickly, usually in fits and starts. These species usually change directions with ease, but a few are not so agile. Nothing is known about how they communicate with each other or whether or not they maintain territories.

Both males and females are usually required for reproduction. A few species are known to reproduce by parthenogenesis (PAR-thuh-no-JEH-nuh-sihs), where the larvae (LAR-vee), or young, develop from unfertilized eggs. The eggs go through a short pupalike stage before they hatch. A pupa (PYU-puh) is the life stage between larva and adult. In one group of pauropods the larvae hatch with three pairs of legs. With each molt, or shedding of the exoskeleton, or hard outer covering, the total number of legs changes to five, six, and eight pairs. In all other pauropods the hatching larvae start with six pairs of legs.

YOU NEVER KNOW UNTIL YOU LOOK

Since 1866 more than seven hundred species of pauropods have been described, but there may be two thousand to three thousand species awaiting discovery, possibly more. In 2002, a retired high school teacher from Sweden, the world's only authority on the group, paid a visit to Great Smoky Mountains National Park. Only five species of pauropods were known from the park, but in just three weeks he found at least forty-four species, twelve of which were new to science.

PAUROPODS AND PEOPLE

Pauropods are small and secretive animals that are overlooked by most people, even trained scientists. One species (Saintpaulia) in the Netherlands is known to damage greenhouse cuttings, but all others do not impact people or their activities.

CONSERVATION STATUS

There are no pauropods considered endangered or threatened. They are so poorly known that little thought has been given to their conservation.

NO COMMON NAME (Allopauropus carolinensis): SPECIES ACCOUNT

Physical characteristics: They are white or whitish and measure 0.039 inches (1 millimeter) in length. They can only be identified with the aid of a microscope.

Geographic range: This species is found in the eastern United States, however not enough studies have been completed to determine how many states should be included.

Habitat: This species is found in forests and woodlands.

Diet: They probably feed on funguses.

Behavior and reproduction: This species is very active but not well studied. Nothing is known about their mating or reproductive behavior.

Allopauropus carolinensis and people: This species does not impact people or their activities.

Conservation status: This species is not considered endangered or threatened. ∎

FOR MORE INFORMATION

Books:

Dindal, D. L., ed. Soil Biology Guide. New York: John Wiley and Sons, 1990.

Eisenbeis, G., and W. Wichard. Atlas on the Biology of Soil Arthropods. Berlin, Germany: Springer-Verlag, 1987.

Periodicals:

Scheller, U. "The Pauropoda (Myriapoda) of the Savannah River Plant, Aiken, South Carolina." Savannah River Plant and National Environmental Research Park Program 17 (1988): 1–99.

Scheller, U. "Pauropoda. The Little Ones Among the Myriapods." ATBI Quarterly 3, No. 4 (2002): 3.