INVERTEBRATE ZOOLOGY IN THREE VOLUMES - BOOK 2 - H.I. Shcherbak - 1996

PHYLUM ARTHROPODA

SUBPHYLUM CHELICERATA

CLASS ARACHNIDA

SUBCLASS SOLIFUGAE

Solifugae predominantly inhabit arid tropical Regions of the Earth, though they are also found in warm temperate zones. About 700 species are known. In Ukraine, only a single species is recorded — Galeodes araneoides (see Fig. 189, c), distributed along the southern coast of Crimea, the right-bank region of the lower Dnieper, and the northeastern part of the Azov Sea region.

Solifugae are generally quite large arachnids (ranging from 50 to 70 mm in length), with only a few species measuring under 10 mm. The largest known species, Galeodes fumigatus, inhabits the sands of Turkmenistan. The prosoma of solifuges includes only those segments bearing the chelicerae, pedipalps, and the first two pairs of walking legs. The segments of the third and fourth pairs of legs are free. The opisthosoma is large and consists of 10 segments. The body and appendages of solifuges are densely covered with hairs and setae of varying thickness and length, giving them a distinctly shaggy appearance.

The chelicerae are exceptionally large, featuring a thickened basal segment and powerful claws. Males possess appendages of various shapes on their chelicerae, which likely serve to secrete pheromones used by the male to mark his territory during the mating season. The pedipalps resemble legs, but lack claws on the tarsus, terminating instead in bulbous adhesive Organs. The Functions of the pedipalps are diverse: they assist in locomotion, including climbing rocks and trees, and are used to capture and restrain prey.

Solifuges respire via a tracheal system that is more developed than in many other arachnids: tracheal tubes extending from the spiracles unite into robust longitudinal trunks with transverse connectives. Numerous branching tracheae extend from the longitudinal trunks to all organs (see Fig. 192, b).

Solifuges are strictly carnivorous predators and exceptionally voracious animals. When hunting, they move rapidly, instantly seizing and firmly securing their prey before tearing and crushing it with their chelicerae. Their diet includes various insects, spiders, small lizards, and nestling birds; cannibalism is also common, with females typically consuming weaker males. If a solifuge is provided with an unlimited supply of food, it may overeat to the point of rupturing its abdomen. In nature, however, this does not occur, as an excessively distended abdomen causes the solifuge to lose mobility.

Most solifuges are nocturnal, although There are also diurnal, sun-loving species.

Solifuges lack venom glands, making their bite harmless to humans. Nevertheless, only large-sized solifuges with powerful chelicerae are capable of piercing human Skin.

Unlike scorpions and pseudoscorpions, Fertilization in solifuges occurs via the direct transfer of a spermatophore by the male (using his chelicerae) into the female's genital opening. This is preceded by a brief courtship in which the male strokes or simply touches the female with his pedipalps before grasping her abdomen with the claws of his chelicerae.

Following fertilization, the female feeds intensively and then digs a burrow where she deposits her eggs (ranging from 20 to 300 depending on the species). Two to four weeks later, young solifuges hatch. They are nearly motionless and enveloped in a transparent membrane; a week later, they molt to emerge as nymphs that externally resemble adult solifuges. However, they do not feed until the subsequent molt transforms them into second-stage nymphs, which begin hunting and burrowing. Nymphs go through approximately nine instars. Females care for the eggs and young; they are even known to bring food to them.