Arthropod Thumbnails
Arthropod/Fish/Amphib Quiz
Arthropod Spotlights (18)

Scorpions (general info) and Spiders

• Bark Scorpion (Centruroides exilicauda)
• Giant (or Desert) Hairy Scorpion (Hadrurus arizonensis)
• Tarantula (Aphonopelma spp)
• "Black Widow" (Latrodectus hesperus)
• Brown ("Recluse") Spider (Loxosceles spp)

Insects and Other Arthropods

• Millipede, Desert (Orthoporus ornatus)
• Centipede, Giant Desert (Scolopendra heros)
• Beetle, Pinacate (Eleodes spp)
• Sphinx Moth, White-Lined (Hyles lineata)
• Tarantula Hawk (Hemipepsis/Pepsis spp)
• Velvet Ant (Wasp) (Dasymutilla spp)
• Bee, Carpenter (Xylocopa spp)
• Ant, Leaf-cutter (Acromyrmex and Atta)
• Grasshopper, Pallid-Winged (Trimerotropis pallidipennis)
• Grasshopper, Creosote Bush (Ligurotettix coquilletti)
• Termites (Isoptera)
• Bug, Cochineal (Dactylopius confusus)
• Beetle, Convergent Ladybird (Hippodamia convergens)

Arthropods include arachnids, insects, millipedes, centipedes, crustaceans, and other invertebrate animals with jointed, external skeletons (exoskeletons). Over 85% of all animal species are arthropods (more than a million species have been officially described and named and there may be over 10 times that many not officially named yet).

Arachnids (e.g., scorpions, spiders, ticks, and mites) have 8 legs, simple eyes, no wings, no antennae, and usually no mandibles (instead they have fang-like mouthparts for piercing). They have 2 major body parts -- cephalothorax (combined head and thorax) and abdomen. Most species are terrestrial.

Insects (e.g., beetles, bees, bugs, and butterflies) have 6 legs, compound eyes, wings (in many but not all species), one pair of antennae, and mandibles. They have 3 major body parts -- head, thorax, and abdomen. Species are both aquatic and terrestrial.

Millipedes have cylindrical bodies with many small legs, 2 pairs of legs per apparent segment. Centipedes have flattened bodies with 15 or more legs, 1 pair of legs per segment. Species are terrestrial.

Crustaceans (e.g., shrimp, crabs, and sowbugs) have more than 8 legs, compound eyes in many, no wings, 2 pairs of antennae, and mandibles. Species are mostly marine, but look for sowbugs (commonly called rollypollies) under rocks in your backyard.

Major sources of information include Alden et al. (1999), ASDM (2000), Bailowitz and Brock (1991), Glassberg (2001), Opler and Wright (1999).