Arachnids & Insects

It would be impossible to detail every type of insect flying, hopping or crawling on Gaia. There are spiders, scorpions, flies, mosquitoes, butterflies…all the normal types of insects. There are poisonous and nonpoisonous, some deadly to mankind, some not. Some mosquitoes do carry disease that is harmful to human life. There are several species of domesticated insects, including honey bees, silkworms, and the Sidán silk-weaver spider.


Spiders are found all over the world, presumably except for the poles (as on Earth). Spiders are highly adaptable creatures, so the various species are widespread. All arachnids have eight legs, although the front pair of legs in some species has converted to a sensory function, while in other species, different appendages can grow large enough to take on the appearance of extra pairs of legs.

Almost all extant arachnids are terrestrial. However, some inhabit freshwater environments and, except the oceanic pelagic zone, marine environments as well. They comprise over 100,000 named species, including spiders, scorpions, harvestmen, ticks, mites, and solifuges.

Arachnids are further distinguished from insects by the fact they do not have antennae or wings. Their body is organized into two tagmata, called the prosoma, or cephalothorax, and the opisthosoma, or abdomen. The cephalothorax is derived from the fusion of the cephalon (head) and the thorax and is usually covered by a single, unsegmented carapace. The abdomen is segmented in the more primitive forms, but varying degrees of fusion between the segments occur in many groups. It is typically divided into a preabdomen and postabdomen, although this is only clearly visible in scorpions. In some orders, such as the Acari, the abdominal sections are completely fused.

Like all arthropods, arachnids have an exoskeleton, and they also have an internal structure of cartilage-like tissue called the endosternite, to which certain muscle groups are attached.

Corryn Mawr (Giant Spider)

Corryn Mawr (Giant Spider, Birdeater)

These spiders can have a leg span of up to 28 cm (11 in) and can weigh over 170 g (6.0 oz). Birdeaters are one of the few tarantula species that lack tibial spurs, located on the first pair of legs of most adult males.

In response to threats, the Corryn Mawr (aka birdeaters) stridulate by rubbing setae on their pedipalps and legs. Also when threatened, they rub their abdomen with their hind legs and release hairs that are a severe irritant to skin and mucous membranes. These urticating hairs can be harmful to humans, and the species is considered by some to have the most harmful tarantula urticating hair of all.

Like all tarantulas, the Corryn Mawr have fangs large enough to break the skin of a human (1.9–3.8 cm or 0.75–1.50 in). They carry venom in their fangs and have been known to bite when threatened, but the venom is relatively harmless, and its effects are comparable to those of a wasp’s sting. Tarantulas generally bite humans only in self-defense, and these bites do not always result in envenomation (known as a “dry bite”).

Despite its name and size, it is rare for the giant birdeater spider to actually prey on birds; in the wild, its diet consists primarily of earthworms and large centipedes. However, because of its size and opportunistic predatory behavior, it is not uncommon for this species to kill and consume a variety of insects and small terrestrial vertebrates. In the wild, the tarantula has been observed feeding on rodents, frogs and toads, lizards, and snakes.

Corryn Crwydryn (Tramp Spider)

Corryn Crwydryn (Tramp Spider)

A particularly unpleasant arachnid is the corryn crwydryn (tramp spider, wandering spider, the wanderer). It is known worldwide although its appearance will vary slightly in color. He is big, comes in many shades of brown to nearly black, hairy and aggressive as he only wanders when he’s searching for a mate. This spider’s fangs can pierce through a fingernail or toenail and the neurotoxin it delivers in a bite can be lethal. Although a tropical species, it is being found in crates of imported fruits and vegetables from the southern marches. As spiders are highly adaptive, a few are being found making themselves at home in the northern climes.

The spiders can grow to have a leg span of 13 to 15 cm (5.1 to 5.9 in). Their body length ranges from 17 to 48 mm (0.67 to 1.89 in). The species is distinguished from other related genera by the presence of dense prolateral scopulae (a dense brush of fine hairs) on the pedipalp tibiae and tarsi in both sexes. The presence of a dark linear stripe or stripes on the frontal (dorsal) palps and presence of a single thin black line running anterior-posterior along the dorsal carapace may help identify the wanderer. Other features are the strong ventral marking on the underside of the legs with contrasting dark mid-segments and lighter joints, and the pattern on the ventral (underside) of the abdomen with several rows of black dots, or an overall reddish colour.

The characteristic defensive posture with frontal legs held high is an especially good indicator to confirm a specimen is corryn crwydryn, especially alongside correct colour patterns. During the defensive display, the body is lifted up into an erect position, the first two pairs of legs are lifted high (revealing the conspicuous black/light-banded pattern on the leg underside), while the spider sways from side to side with hind legs in a cocked position.



Like all arthropods, the tarantula is an invertebrate that relies on an exoskeleton for muscular support. Similar to other arachnids, a tarantula’s body comprises two main parts, the prosoma (or cephalothorax) and the opisthosoma (or abdomen). The prosoma and opisthosoma are connected by the pedicle or pregenital somite. This waist-like connecting piece is actually part of the prosoma and allows the opisthosoma to move in a wide range of motion relative to the prosoma.

Tarantula sizes range from as small as a fingernail to as large as a dinner plate when the legs are fully extended. Depending on the species, the body length of tarantulas ranges from 2.5 to 10 centimeters (1 to 4 in), with leg spans of 8–30-centimeters (3–12 in). Leg span is determined by measuring from the tip of the back leg to the tip of the front leg on the opposite side. Some of the largest species of tarantulas may weigh over 85 grams (3 oz). The largest of all, the Corryn Mawr (Giant Spider) has been reported to attain a weight of 150 grams (5.3 oz) and a leg-span of up to 30 centimeters (12 in), males being the longer and females greater in girth.

Sidán Silk-Weaving Spider

Sidán Silk Weaver (female)

The Sidán Silk-Weaver is a large arachnid native to the vasts forest of K’harsten March in Cymeria. It is a social spider that lives in colonies of up to 50,000 individuals. Silk-Weavers have been domesticated for thousands of years, happily adapting to their human handlers.

These spiders weave particularly strong and pliable silken webs. Once harvested, the webs are soaked in a solution made of water, vinegar, and digestive enzymes milked from the spiders. The soaking breaks down the sticky substances and allows for weaving the silk webs into cloth. Many clothiers pick apart the strands of webs and weave them into regular silk or other fabrics to strengthen them. The Sidán silk takes on dyes easily and has a tendency to deepen and enhance the colors. Another aspect of pure Sidán silk is that its folds will entangle spear points and arrows, providing an excellent undershirt for armor and mail.

The mail silk-weavers are very colorful and perform intricate dances to attract a mate.

Male Silk-Weaver