Arthropod Classes

Insects (from Latin insectum) are invertebrates of the class Insecta.

Arachnids are arthropods in the class Arachnida () of the subphylum Chelicerata.

Malacostraca is the second largest of the six classes of pancrustaceans after insects, containing about 40,000 living species, divided among 16 orders.

Millipedes (originating from the Latin mille, "thousand", and pes, "foot") are a group of arthropods that are characterised by having two pairs of jointed legs on most body segments; they are known scientifically as the class Diplopoda, the name derived from this feature.

Centipedes (from Neo-Latin centi- 'hundred' and Latin pes, pedis 'foot') are predatory arthropods belonging to the class Chilopoda of the subphylum Myriapoda, an arthropod group which includes millipedes and other multi-legged animals.

Ostracods, or ostracodes, are a class of the Crustacea (class Ostracoda), sometimes known as seed shrimp.

Branchiopoda (from Ancient Greek βράγχια (bránkhia), meaning "gill", and πούς (poús), meaning "foot") is a class of crustaceans.

Symphylans, also known as garden centipedes or pseudocentipedes, are soil-dwelling arthropods of the class Symphyla in the subphylum Myriapoda.

Pauropoda is a class of small, pale, millipede-like arthropods in the subphylum Myriapoda.

Merostomata is a class of chelicerate arthropods that contains the extinct Eurypterida (sea scorpions) and the extant Xiphosura (horseshoe crabs).

Copepods (; meaning 'oar-feet') are a group of small crustaceans found in nearly every freshwater and saltwater habitat.

Sea spiders are marine arthropods of the class Pycnogonida, hence they are also called pycnogonids (; named after Pycnogonum, the type genus; with the suffix -id).