Coastal tide pools, coral reefs, and forest leaf litter are full of creatures without backbones, playing key roles in food webs and ecosystems. Whether you study marine biology or just enjoy a beach walk, spotting shells, crabs, or colorful sea stars offers a quick lesson in diversity and adaptation.
There are 21 Examples of Invertebrates, ranging from the American lobster to the Purple sea urchin to show the geographic and ecological span. For each entry you’ll find below concise fields organized as Scientific name, Phylum, Habitat/Range so you can compare classification and where each species lives.
What counts as an invertebrate and how are they classified?
Invertebrates are animals that lack a vertebral column; they include groups like arthropods, mollusks, echinoderms, and cnidarians. Classification in the list uses taxonomic rank (Scientific name) and broader groupings (Phylum) so you can see both species-level identity and where it fits in the tree of life.
How should I use this list to find species near me?
Start by scanning the Habitat/Range column for your region, then match common names or Scientific name to photos or local field guides. The organized columns make it easy to narrow candidates and follow up with regional resources or citizen science apps for confirmation.
Examples of Invertebrates
| Name | Scientific name | Phylum | Habitat/Range |
|---|---|---|---|
| Monarch butterfly | Danaus plexippus | Arthropoda | Fields, meadows, and forests; North America to Mexico (migratory) |
| Honey bee | Apis mellifera | Arthropoda | Worldwide in meadows, farms, and managed hives |
| Housefly | Musca domestica | Arthropoda | Worldwide around human habitations, farms, and waste sites |
| Garden orb weaver | Araneus diadematus | Arthropoda | Gardens, hedgerows, and woodlands; temperate regions of Europe and North America |
| Praying mantis | Mantis religiosa | Arthropoda | Grasslands, gardens, and shrublands; Europe, Asia, North America (introduced) |
| Common pill bug (roly‑poly) | Armadillidium vulgare | Arthropoda | Moist leaf litter, gardens, and under stones; worldwide in temperate regions |
| American lobster | Homarus americanus | Arthropoda | Cold Atlantic coastal waters; northeastern North America |
| Common millipede | Narceus americanus | Arthropoda | Leaf litter, logs, and soil in forests; eastern North America |
| Blue mussel | Mytilus edulis | Mollusca | Intertidal and subtidal rocky shores; North Atlantic and adjoining seas |
| Garden snail | Cornu aspersum | Mollusca | Gardens, hedgerows, and urban areas; native to Europe, now worldwide |
| Common octopus | Octopus vulgaris | Mollusca | Shallow coastal waters and reefs; worldwide in temperate to tropical seas |
| Giant clam | Tridacna gigas | Mollusca | Coral reef lagoons; Indo‑Pacific tropics |
| Earthworm | Lumbricus terrestris | Annelida | Soils in gardens, fields, and forests; cosmopolitan in temperate regions |
| Moon jelly | Aurelia aurita | Cnidaria | Coastal waters and harbors; temperate and tropical seas worldwide |
| Box jellyfish | Chironex fleckeri | Cnidaria | Warm coastal waters and mangroves of the Indo‑Pacific, northern Australia |
| Common starfish (sea star) | Asterias rubens | Echinodermata | Rocky shores and tidal zones; North Atlantic coasts |
| Purple sea urchin | Strongylocentrotus purpuratus | Echinodermata | Rocky intertidal and subtidal zones; Pacific coast of North America |
| Caenorhabditis elegans | Caenorhabditis elegans | Nematoda | Soil, compost, and leaf litter worldwide; also lab cultures |
| Planarian flatworm | Dugesia dorotocephala | Platyhelminthes | Freshwater streams, ponds, and springs; temperate regions |
| Bath sponge | Spongia officinalis | Porifera | Shallow Mediterranean and tropical seas on rocky or coral substrates |
| Emperor scorpion | Pandinus imperator | Arthropoda | Tropical forests and savannas; West and Central Africa |
Images and Descriptions
Monarch butterfly
Bright orange-and-black butterfly with a 9–10 cm wingspan. Famous for dramatic seasonal migrations of up to 3,000 km; caterpillars eat milkweed, which makes adults distasteful to predators and helps them survive long journeys.
Honey bee
Small, fuzzy pollinator about 1.2 cm long that lives in large colonies. Essential for pollinating many crops, honey bees communicate location of flowers by dancing and produce honey and beeswax used by people worldwide.
Housefly
Common 6–7 mm fly often seen indoors and outdoors. Larvae develop in decaying matter; adults can spread bacteria and viruses but also play a role in nutrient recycling by breaking down organic waste.
Garden orb weaver
Orb-weaving spider with a round abdomen about 1–2 cm long that builds sticky, wheel-shaped webs to catch flying insects. Not dangerous to people and often visible in the evening when repairing its web.
Praying mantis
Lean, green or brown predatory insect about 6–7 cm long that ambushes prey with folded “praying” forelegs. Notable for excellent camouflage and some species’ head rotation for scanning their environment.
Common pill bug (roly‑poly)
Small terrestrial crustacean about 1 cm long that rolls into a tight ball when threatened. Eats decaying plant material and helps recycle nutrients in soil and garden compost.
American lobster
Large marine crustacean reaching up to 60 cm in length with powerful claws used for crushing and cutting. Valued as seafood, lobsters can live decades and molt their shells as they grow.
Common millipede
Cylindrical, many‑segmented arthropod reaching around 10 cm with two pairs of legs per segment. Slow-moving detritivore that curls into a coil when disturbed and helps decompose dead plant material.
Blue mussel
Bivalve mollusk with a bluish-black shell 5–10 cm long that attaches to rocks in dense beds. Filters seawater for plankton, improving water clarity, and serves as a food source for many animals and people.
Garden snail
Terrestrial snail with a rounded shell about 2–4 cm across that carries its home on its back. Uses a muscular foot to glide and retracts into its shell for protection and moisture conservation.
Common octopus
Flexible-bodied cephalopod with an arm span around 1 m, eight arms and a soft mantle. Highly intelligent, capable of problem solving and rapid camouflage by changing color and texture.
Giant clam
Massive bivalve that can exceed 1.2 m across and live for over 100 years. Harbors symbiotic algae in its tissues that provide much of its energy and give the clam bright colors.
Earthworm
Burrowing segmented worm up to 20–25 cm long that aerates soil and breaks down organic matter. Essential for healthy soils, earthworms improve drainage and nutrient availability for plants.
Moon jelly
Translucent, saucer-shaped jellyfish with a bell up to 40 cm across and trailing tentacles. Uses stinging cells to catch tiny plankton; their mild sting is usually harmless to humans.
Box jellyfish
Square-shaped jellyfish with a bell about 20 cm and long tentacles carrying potent venom. Notable for causing severe, sometimes fatal, stings in people; extremely efficient swimmers compared with many jellyfish.
Common starfish (sea star)
Five-armed echinoderm with an arm span of 20–30 cm that moves using tube feet. Can regenerate lost arms and some species can evert their stomach to digest prey outside their body.
Purple sea urchin
Spherical echinoderm about 5–10 cm across covered in sharp spines used for protection and locomotion. Grazes on algae and can shape kelp forest communities by overgrazing when abundant.
Caenorhabditis elegans
Tiny roundworm about 1 mm long widely used as a research model. Simple nervous system of 302 neurons is fully mapped, making it invaluable for genetics and developmental biology studies.
Planarian flatworm
Small flatworm typically a few millimeters to a few centimeters long with remarkable regenerative ability. Can regrow entire bodies from small fragments and is used to study regeneration and stem cells.
Bath sponge
Porous marine sponge that filters water to feed, with a soft skeleton once used as a natural bath sponge. Can pump thousands of liters of water per day through its internal canal system.
Emperor scorpion
Large scorpion reaching up to 20 cm including tail, glossy black and nocturnal. Uses pincers to subdue prey and a venomous sting mainly for small animals; sting rarely lethal to humans.
