Insect Morphology, Taxonomy and Metamorphosis
Insect morphology, taxonomy and metamorphosis examines the insect body plan, mouthpart and appendage types, developmental stages, and the economic orders.
Core rules
- Body: head (antennae, compound eyes, mouthparts), thorax (three segments; three pairs legs; usually two pairs wings), abdomen (viscera, spiracles).
- Mouthparts: biting-chewing (grasshopper), piercing-sucking (aphid, bug), siphoning (butterfly), sponging (housefly), lapping (honey bee), rasping-sucking (thrips).
- Legs: cursorial, saltatorial, fossorial, natatorial, raptorial, clinging. Antennae: filiform, setaceous, moniliform, clavate, lamellate, serrate, plumose, aristate.
- Wings: tegmina (Orthoptera), elytra (Coleoptera), hemelytra (Hemiptera), halteres (Diptera), scaled wings (Lepidoptera).
- Metamorphosis: ametabolous (silverfish), hemimetabolous (nymph resembles adult; grasshopper), holometabolous (egg-larva-pupa-adult; butterfly).
- Larvae: campodeiform, scarabaeiform, elateriform, vermiform, eruciform, apodous. Pupae: exarate, obtect, coarctate.
Worked example
An insect has forewings leathery at base and membranous at tip, piercing-sucking mouthparts, and gradual metamorphosis. The hemelytra and mouthparts place it in Hemiptera, not Coleoptera (elytra, biting-chewing, complete metamorphosis).
Traps
Do not call all larvae caterpillars; eruciform is specific to Lepidoptera-like forms. Diptera have one functional wing pair. Hemimetabolous insects lack a pupal stage.