An amblypygid is an invertebrate animal belonging to the order Amblypygi in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda.

Amblypygids are also known as "tailless whip scorpions". The name "amblypygid" means "blunt rump", a reference to a lack of the telson ("tail") carried by related species.

As of 2002, approximately 5 families, 17 genera and 136 species have been described. They are found in tropical and subtropical regions worldwide. Some species are subterranean; many are nocturnal. During the day, they may hide under logs, bark, stones, or leaves. They prefer a humid environment.

Physical description

Amblypygids may range from 5 to 40 mm. Their bodies are broad and highly flattened and the first pair of legs (the first walking legs in most arachnid orders) are modified to act as sensory organs. (Compare solifugids, uropygids, and schizomids.) These very thin modified legs can extend several times the length of body. They have no silk glands or poisonous fangs, but can have prominent pincer-like pedipalps.

Behavior

Amblypygids often move about sideways on their six walking legs, with one "whip" pointed in the direction of travel while the other probes on either side of them. Prey are located with these "whips", captured with pedipalps, then torn to pieces with chelicerae.

Courting rituals involve the male guiding the female with his pedipalps over spermate deposited into one or more sperm masses. She gathers the spermate and lays fertilized eggs into a sac carried under the abdomen. When the young hatch, they climb up onto the mother's back; any which fall off before their first molt will be eaten by the mother.

History

Fossilized amblypygids have been found dating back to the Carboniferous period.

Also see

List of amblypygid genera