They mostly hunt for spiders, roaches, and other small critters. Like all scorpion species, they possess a modified segment at the end of the tail containing a stinger that delivers venom. It is most often used to immobilise prey and defend against predators; males use it in fights with other males. (3) Tailless Whip Scorpions Related to scorpions and spiders are the Tailless Whip Scorpions or Amblypigids. These nocturnal arachnids have long legs, two large muscular arms in the front that are equipped with long spikes and barbs used to impale and secure prey, and two long whip-like legs that are used to detect potential prey moving about their habitats or to warn of impending danger. They are not dangerous and do not have venom, though the spiny legs may give a painful pinch if they are handled improperly. They are extremely shy and quickly skitter off when disturbed. At least two species occur on Tortola and Beef Island, including the Long-legged Whipspider (Phrynus longipes), the larger of the two. It can reach body lengths of up to about 3.5 cm (1.4 in), with whip-like legs reaching another 8 cm (3 in). This species hunts and feeds on spiders and other invertebrates including roaches and worms, but also lizards, small snakes, frogs and even small birds such as hummingbirds. Photo 59 shows a mediumsized specimen at Beef Island. They spend the day hiding under rocks, in caves, under bark, in heavy litter and in the dead leaf bases of Agave plants.
animals, spiders should be handled with care. They are major predators of many pest species, including flies, mosquitoes, roaches and even other spiders. Some of the more visible species on Tortola are the largest of the orb-weavers, the Writing Spider or Golden Silk Spider (Nephila clavipes). Females grow much larger than males, dwarfing them by many magnitudes. The male will often spend its life in the web of the female, with whom he may mate, after which he may be eaten by her. Photo 60 shows a large and colourful female at Arundel near Sage Mountain. The term “writing” used in the common name refers to the patterns of “zig zags” created by the females toward the centre of the web, reminiscent of lettering or some foreign language script.
Photo 60. A female Golden Silk Orb-weaver Spider, at Arundel, Tortola.
A more ancient cousin of the Writing Spider is the group often called tarantulas. Several species are present, although not all have been studied. Some are fairly large and live in holes in the ground. These holes are often lined with fine silk, which prevents the tunnel from collapsing inward, keeping it free of debris. The Ground Tarantula (Cyrtopholis bartholomei) is the largest of the Virgin Islands species, achieving lengths of up to 13 cm (5 in). Photo 59. Long-legged Whipspider from Beef Island, Tortola.
(4) Spiders Closely related to the Amblypigids are the true spiders. Many species occur on Tortola, some relatively large, although none are deadly. Like all wild
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As with many spider species, females are bigger than the males and possess a larger and more rounded abdomen, which allows them to carry eggs and care for the young. Photo 61 shows the Greater Antillean endemic, found in Hispaniola, Puerto Rico and the Virgin Islands. It builds shallow borrows below rocks, logs, roots, and leaf litter or