Proturans

jy^J EMBERS or THE ORDKR Protura, J which contains 4 families and 400 species, are soil-dwelling hexapods. The first specimens were discovered in 1907.

These tiny creatures have neither eyes nor antennae, although there is a pair of tiny patches on either side of the head that may he the vestiges of antennae. In place of antennae, the front pair of legs are used as sensory organs. The middle and hind pairs are used for walking. Like springtails (see pp.207-209) and diplurans (see p.211), proturans have piercing-sucking mouthparts that are contained inside a pouch and pushed out whenever the animal is feeding. The jaws are sharp and rodlike in appearance.

The first three abdominal segments may have minute vestiges of leglike structures. There are no cerci.

During mating, sperm is transferred indirectly, with the male depositing a spcrmatophore on the ground that is picked up by the female's genitalia. When the larvae hatch out from the eggs, the abdomen has eight segments and a tail segment (telson). By the time they have molted three times, proturans have the full complement of eleven abdominal segments plus the telson. Another two molts are required before they become sexually mature.

Order pR()TURA

Family KOSKNTOMIIMK

No. of species 9Q

Eosentomids

Pale and soft-bodied, these hexapods have a conical head and elongate body. The legs do not project far from the body, which allows easy passage through tiny cracks and crevices. The front legs arc stouter than the middle and hindlegs and have numerous hairs and other sensory organs. Spiracles are visible on the middle and hind segments of the thorax.

• Life CYCLE The eggs are round and patterned or have raised warts, and are usually laid in soil or leaf litter. The larvae look much like small adults.

• OCCl JRRENCE Worldwide. In a variety of habitats, preferably in damp, cool conditions. Eosentomids occur in great numbers in soil, leaf litter, moss, humus, and decaying wood.

legs have a single, spine-like claw pair of legs on each of three \ thoracic segments legs have a single, spine-like claw pair of legs on each of three \ thoracic segments

EOSENTOMON DEUCATUM is native to Europe, and the genus as a whole is found all over the world. This species lives in soil, especially chalky soils.

pale and elongate body remains of leglike structures on first three abdominal 1 segments remains of leglike structures on first three abdominal 1 segments

large front legs conical, eyeless head large front legs conical, eyeless head

Eosentomon spkc :iks are usually found living near the surface of soil or leaf litter.

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