Animal Encyclopedia

Insects & Invertebrates

Insects are the most species-rich class of animals on Earth — with over one million described species and estimates of the true total running far higher. Together with other invertebrates such as spiders, they have colonised virtually every land and freshwater habitat and perform ecological functions indispensable to global food systems, including pollination, decomposition, and forming the base of many food webs.

Ecology guidePollinators: bees, butterflies, birds, bats, flies & beetlesHow pollination works across animal groups — with source-backed, cautious notes.

Insect & Invertebrate Profiles

Each profile is a cautious, group-level overview rather than a single-species monograph. We cover anatomy, life cycle, habitat, diet, and ecological role, and we note where a common name spans many species. Spiders are included here as familiar invertebrates, with a clear reminder that they are arachnids, not insects.

Bee

Clade Anthophila — vital pollinators; a group-level overview using the honey bee.

Butterfly

Order Lepidoptera — day-flying insects with a four-stage life cycle.

Ant

Family Formicidae — highly social insects living in organised colonies.

Dragonfly

Infraorder Anisoptera — fast aerial predators with aquatic larvae.

Ladybug

Family Coccinellidae — small beetles, many of them helpful aphid predators.

Praying Mantis

Order Mantodea — ambush predators with grasping forelegs and keen eyesight.

Spider

Order Araneae — eight-legged arachnids (not insects) that produce silk.

Beetle

Order Coleoptera — the most species-rich animal group, with hardened wing cases.

Scorpion

Order Scorpiones — arachnids with pincers and a venomous tail sting.

Earthworm

Annelida — segmented worms that aerate and enrich the soil.

Tarantula

Theraphosidae — large, hairy spiders, mostly calm and only mildly venomous.

Centipede

Chilopoda — fast, venomous, many-legged predators (one leg pair per segment).

Millipede

Diplopoda — slow, harmless litter recyclers (two leg pairs per segment).

Moth

Lepidoptera — mostly night-flying insects that outnumber butterflies.

Grasshopper

Caelifera — plant-eating insects with powerful jumping legs.

Snail

Shelled gastropod molluscs that glide on a muscular foot.

Slug

Shell-less gastropod molluscs; close relatives of snails.

Cicada

Family Cicadidae — loud summer singers whose nymphs live underground for years.

Cricket

Family Gryllidae — chirping insects that sing by rubbing their wings.

Stick Insect

Order Phasmatodea — masters of camouflage that mimic twigs and leaves.

Wasp

Order Hymenoptera — feared for their sting, but vital pest controllers and pollinators.

Termite

Order Isoptera — social wood-recyclers and mound-builders (actually a kind of cockroach).

Tardigrade (Water Bear)

Phylum Tardigrada — microscopic animals that survive almost anything, even space.

Cockroach

Order Blattodea — ancient, hardy insects; mostly wild recyclers, a few are pests.

Crayfish

Lobster-like freshwater crustaceans; recyclers, and invasive where introduced.

Velvet Worm

Phylum Onychophora — ancient soft-bodied predators that shoot sticky slime.

Mayfly

Order Ephemeroptera — short-lived adults; nymphs indicate clean fresh water.

Woodlouse

Suborder Oniscidea — the only crustaceans fully adapted to land; harmless soil recyclers.

Lacewing

Order Neuroptera — lacy-winged insects whose 'aphid lion' larvae devour garden pests.

Aphid

Family Aphididae — tiny sap-suckers that clone themselves and are 'farmed' by ants for honeydew.

Antlion

Family Myrmeleontidae — larvae ('doodlebugs') dig conical sand traps to catch ants.

Weevil

Family Curculionidae — long-snouted beetles; one of the largest animal families, with notable crop pests.

Thrips

Order Thysanoptera — minuscule fringe-winged insects; pollinators and pests ('thrips' is singular too).

Earwig

Order Dermaptera — pincer-tailed insects that guard their young; the ear-burrowing tale is a myth.

Leafhopper

Family Cicadellidae — small sap-sucking jumpers that coat themselves in water-repelling brochosomes; many are crop pests.

Tick

Order Ixodida — eight-legged arachnids (not insects) that feed on blood; some species can transmit disease, varying by species and region.

Mite

Subclass Acari — a vast, diverse arachnid group; the red velvet mite is a harmless soil predator.

Leech

Subclass Hirudinea — segmented worms (annelids) with suckers; the medicinal leech is the best-known species.

Dung Beetle

Subfamily Scarabaeinae — beetles that recycle animal dung; 'rollers' shape and bury dung balls, vital to African savannas.

Tsetse Fly

Genus Glossina — blood-feeding African flies; some can transmit the parasites that cause sleeping sickness and nagana.

Asian Giant Hornet

Vespa mandarinia — the world's largest hornet, a social wasp of East and South Asia that preys on other insects.

Silkworm

Bombyx mori — the fully domesticated silk moth, reared for silk (sericulture) since ancient China.

Stag Beetle

Lucanus cervus — one of Europe's largest beetles; males have antler-like jaws and larvae develop in dead wood.

Monarch Butterfly

Danaus plexippus — an orange-and-black butterfly famous for its long multi-generational migration to Mexico.

Luna Moth

Actias luna — a large pale-green silk moth of eastern North American forests; adults do not feed.

Blue Morpho Butterfly

Genus Morpho — large Neotropical butterflies with brilliant iridescent blue wings (a structural colour).

Leafcutter Ant

Atta and Acromyrmex — Neotropical ants that cut leaves to farm an edible fungus underground.

Goliath Birdeater

Theraphosa blondi — the largest spider in the world by body mass, a tarantula of South American rainforest.

Amazonian Giant Centipede

Scolopendra gigantea — one of the largest centipedes, a fast venomous predator of northern South America.

Box Jellyfish

Class Cubozoa — cube-bodied jellyfish of Indo-Pacific coasts; some species have medically significant venom.

Crown-of-thorns Starfish

Genus Acanthaster — a spiny, coral-eating sea star of Indo-Pacific reefs whose outbreaks can damage coral.

Funnel-web Spider

Family Atracidae — Australian burrowing spiders; some species have medically significant venom.

Redback Spider

Latrodectus hasselti — a widespread Australian widow-relative; the female has a red back stripe.

Giant Weta

Genus Deinacrida — very large flightless insects endemic to New Zealand; several species are threatened.

Antarctic Krill

Euphausia superba — a small, swarming crustacean that is a keystone of the Southern Ocean food web.

Bumblebee

Genus Bombus — robust, hairy social bees and effective buzz pollinators of many plants.

Carpenter Bee

Genus Xylocopa — large bees that nest in wood and pollinate many flowers.

Mason Bee

Genus Osmia — gentle solitary bees and efficient early-spring pollinators.

Leafcutter Bee

Family Megachilidae — solitary bees that cut leaf discs and carry pollen on belly hairs.

Orchid Bee

Tribe Euglossini — brilliant metallic Neotropical bees that pollinate certain orchids.

Painted Lady

Vanessa cardui — one of the world's most widespread butterflies and a long-distance migrant.

Hawk Moth

Family Sphingidae — strong-flying moths; many are key nocturnal pollinators of long-tubed flowers.

Hummingbird Hawk-moth

Macroglossum stellatarum — a day-flying moth that hovers at flowers like a hummingbird.

Hoverfly

Family Syrphidae — flower flies that mimic bees and wasps but cannot sting; underrated pollinators.

Longhorn Beetle

Family Cerambycidae — long-antennaed beetles; flower-visiting species pollinate as they feed.

Fig Wasp

Family Agaonidae — tiny wasps in an obligate mutualism pollinating fig trees.

Pollen Wasp

Subfamily Masarinae — unusual wasps that provision nests with pollen and nectar.

Why Insects & Invertebrates Matter

Insects pollinate a large share of the world's flowering plants and many food crops, while beetles, flies, and other invertebrates are primary decomposers that break down organic matter and cycle nutrients back into soil. Spiders and predatory insects help regulate the numbers of other invertebrates. Many vertebrate species — including birds, fish, amphibians, and mammals — depend on insects and other invertebrates as a primary food source. Documented declines in some insect populations are a significant ecological concern with cascading effects across ecosystems.