Tarantula Glossary

apolysis- another word for molting or ecdysis; when a spider sheds its exoskeleton
arachnid- arthropods with four pairs of legs and one pair of pedipalps (sometimes in the form of claws). Scorpions are arachnids. So are tarantulas and garden spiders.
araneae- an order of arachnids commonly called "spiders". Black widows are a member of this order and so are tarantulas. Scorpions are not.
arboreal- Lives in off the ground, like in trees
arthropods- bugs like insects, spiders, centipedes. . . the whole lot of 'em
book lungs- Little flaps on the underside of a tarantula's opisthosoma (abdomen) that it breathes with. There are four.
carapace- This is the top half of the cephalothorax and is hardened, yet often has a thin mat of fur. The eyes protrude from the top of the carapace.
cephalothorax- This is the forward section of a tarantula that all the legs come out of. It's akin to both the head and thorax on insects, all in one neat package. It has the eyes (all eight of 'em), the chelicerae and fangs, and the tarantula's brain is inside. Also called the "prosoma."
chelicerae- extensions that come out of the cephalothorax . They contain hinges upon which the fangs move; i.e., the "top part of the fangs". They are the "basal" segment of the mandible.
CITES- Convention on International Trade in Endangered Species. Tarantulas from the genus Brachypelma are on CITES.
coxa- Where a tarantula's legs attach to its cehpalothorax
ecdysis- when a tarantula sheds its exoskeleton in order to grow
epigastric furrow- A slit betwixt the two forward book lungs that contains a tarantula's reproductive mechanisms
femur- The long leg segment close to a tarantula's body, like your femur
fovea, or thoracic fovea- An indentation in the carapace of a tarantula
hybrid- the offspring of two different species.
instar-A period between molts in a tarantula's life. A tarantula in its 5th instar has shed its "skin" five times.
keystone species- An animal that is crucial to its niche, or habitat. Some tarantulas are keystone species due to their diets.
mandible- consists of chelicerae and fangs
metatarsus- the leg segment between the tibia and the tarsus. There is no metatarsus on the pedipalps.
molt- the same as ecdysis: when a tarantula sheds its exoskeleton in order to grow. They usually lie on their backs to do this.
mygalomorphae- an infraorder of spiders with fangs that move on a horizontal plane (straight up and down). Tarantulas are a type of mygalomorph. So are trapdoor spiders.
new world- Tarantulas from the Americas
ocular tubercle- The raised section on the carapace that has clear little domes that a tarantula's eyes can see through
old world- Tarantulas from Asia, Africa, and Europe.
opisthosoma- The "rearward" section of the tarantula that contains the spinnerets, the book lungs, the epigastric furrow, and the anus. The heart is also inside the opisthsoma, so be careful! In the case of most New World species, the opisthosoma has urticating hair. Also called the "abdomen".
opportunistic burrower- A tarantula that seeks a provided shelter instead of constructing its own from scratch.
oviparous- egg-laying. All tarantulas are oviparous- that is, they do not give birth to feeding, breathing young.
patella- the leg segment between the femur and tibia (you may think of it as a spider's "knee").
pedicel- small tube that connects the opisthosoma to the prosoma.
pedipalp- Like a tarantula's "arms." Located on the sides of the chelicera and used to grasp prey, serve as "feelers," etc., they look like smaller, extra legs. However, the pedipalps only have six segments (legs have seven). Males put sperm in the ends of their pedipalps to mate with. Scorpions have claws for pedipalps.
plumose- Literally, "feathery." Used to describe some of a tarantula's "hair."
prosoma- The "front" section of the tarantula that contains the carapace, eyes, fangs, etc.
rastellum- spines that overhang the mandible. Most mygalomorphs have these. Tarantulas do not.
scopula- Dense hairs of uniform length on a tarantula's "feet"
sigilla- indentations on a spider's sternum.
species- a natural population that can breed and produce fertile offspring.
spinnerets- Appendages on the rear of a tarantulas that are used to spin webbing.
spiderling or s'ling- Baby tarantula
stridulate- when a tarantula makes a hissing sound by rubbing specialized hairs on their chelcerae and pedipalps. It means the spider is upset.
substrate- the substance placed on the floor of a terrarium. Usually dirt, peat moss, sand, vermiculite, etc.
tarsus- the last leg segment; the equivalent of the foot.
taxonomy- the study of the relationship of different species
terrestrial- A tarantula that lives on or in the ground, as opposed to arboreal ones that live in trees and on the sides of other structures.
theraphosidae- A family of mygalomorphs commonly called "tarantulas." Actually, a true tarantula is not even a mygalomorph (it's a European wolf spider called Lycosa tarantula) , but the word "tarantula" has come to be more commonly associated with theraphosids, especially in the United States.
tibia- A leg segment away from the tarantula's body, after its "knee," like your tibia. Most mature male tarantulas have a small hook under each tibia.
tibial spurs- hooks on most male tarantulas' tibias that are used to secure a female's fangs while mating
trochanter- the leg segment between the coxa and the femur.
urticating bristle or hair- Teeny tiny barbed hairs on most New World tarantulas' opisthosomas (abdomens) that they can flick off by rubbing their hind legs rapidly against their rears. The result is a an almost unseeable cloud that floats off into the air (with the exception of tarantulas in the genus Avicularia) and will cause potential threats (such as rodents and people) much irritation.
ventral- the underside of something. The ventral surface of a tarantula is its "belly."