Anatomy
Depending on the order / infraorder... there are differences, exceptions and uniqueness. The following is intended to provide a simple overview only.
Ventral view
1 - pedipalp (sensing, handling prey, the last segment contains the secondary sexual organ of the sexually mature male)
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2 - labium (a kind of lip under the mouth opening)
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3 - sternum
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4 - book lungs (for breathing)
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5 - epigynum, epigrastic furrow (access to the female sex organ)
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6 - spinnerets
Dorsal view
1 - pedipalp (sensing, handling prey, the last segment contains the secondary sexual organ of the sexually mature male)
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2 - chelicerae / fangs
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3 - eyes on the cephalothorax (eight, with exceptions)
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4 - carapace / prosoma
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5 - one of eight legs
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6 - abdomen / opistosoma
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7 - spinnerets
Structure of the legs
1 - coxa / tochanter
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2 - femur
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3 - patella
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4 - tibia
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5 - metatarsus
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6 - tarsus
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7 - tarsal claws
Organs
1 - brain
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2 - stomach
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3 - heart
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4 - intestine
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5 - anus
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6 - spinnerets and silk gland
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7 - ovary
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8 - egg exit (gonopore)
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9 - book lung
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10 - chelicera
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11 - venom gland
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Terminology
In the following you will find a small list of various terms that spider owners usually use:
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0.0.1: one spider of undefined gender
0.2.0: two female spiders
4.0.0: four male spiders
Cephalothorax: Prosoma / head
Chelicera, chelicerae: spiders´ jaws, basal segments of the fangs
Coxa: basal segment of spider's leg
Cribellum: a silk spinning organ of Araneomorphae
Cuticle: exoskeleton, consisting of epidermis, mesocuticle, exocuticle and epicuticle
Cymbium: organ used in transferring sperm to the female (on the end of the male's palpal tarsus)
Embolus: end of the male's cymbium
Epigrastic furrow: opening of the genitals for males and females (ventrally on the abdomen between the two forward booklungs)
Epigyne: external female sex organ (copulation organ) in entelegynen true spiders
Exuvium, exuvia: shed skin / exoskeleton
Femur: the third of seven leg segments
Hemolymph: spiders blood
Instar: terminology for stages of growth, in germany it is calles "NS" or "FH" (Nymphenstadium / Fresshaut)
Maxillae: sharp plates on the pedipalps
Metatarsus: sixth of seven leg segments
Molt: process of shedding exoskeleton / the shed skin itself
New world species: tarantulas from North and South America
Old world species: tarantulas from Africa, Asia, and Australia
Opisthosoma: abdomen
Palpal bulbs: male's secondary reproductive organs
Patella: fourth of seven leg segments
Pedicel: connection between opisthoma to cephalothorax
Pedipalps: second pair of appendages attached to the head, they have 6 segments, as opposed to the 7 of the real legs. Mature males tarsal segments are the secondary sexual organs
Prosoma: Cephalothorax
Sling: synonym for spiderling (baby-spider)
Spermathecae: females organ for storing males sperm, one of the most helpful ways for sexing molts
Spermophore: tube inside the palpal bulbs form mature males to transfer sperm
Sternum: plate underneath the prosoma
Stridulate: unique organs to create sounds
Tarsus, tarsi: Seventh leg segment
Tibia, tibiae: Fifth of seven leg segments
Tibial apophysis: hooks from mature males of most species on the tibia used in mating
Trochanter: Second of seven leg segments
Urticating bristles: primary defense mechanism used by new world tarantulas. The spiders kick these hairs against their enemies. It can cause allergic reactions to people
Ventral: bottom
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