Insects & Invertebrates comparison

Earthworm vs Velvet Worm: Key Differences Explained

The short answer

They share a shape and nothing else. An earthworm is an annelid: a truly segmented, legless burrower with a moist slippery skin, bristles called chaetae for grip, and a diet of soil and decaying plant matter. A velvet worm is an onychophoran, a separate phylum, with a dry velvety papillate skin, a pair of antennae, and many pairs of stubby unjointed legs tipped with claws. It is a predator that entangles small invertebrates with a sticky secretion.

The main difference

An earthworm is a legless segmented annelid that eats soil, while a velvet worm is a clawed-legged onychophoran predator with a dry velvety cuticle and antennae.

Photographs of velvet worms are often captioned as caterpillars or odd earthworms, and the pair shows how little a worm-like body plan tells you about relationships, since the two sit in different phyla with different tissue layouts.

At a glance

Comparison of Earthworm and Velvet Worm across 7 dimensions, with an interpretation of each difference.
What differs	Earthworm	Velvet Worm	What it means
Phylum	Annelida, the segmented worms, in the class Clitellata alongside leeches	Onychophora, a small phylum of roughly 200 described species related to arthropods	They are not distant cousins within one group; they belong to different phyla entirely.
Legs	None; movement uses waves of muscle contraction with tiny bristles gripping the burrow wall	Many paired stubby unjointed lobopods, each tipped with a pair of claws	Legs are the fastest diagnostic in the field, visible even in a poor photograph.Leg-pair counts differ by species, commonly falling somewhere between about 13 and 43 pairs.
Body surface	Moist, slippery and shiny, with clear ring-like grooves marking true segments	Dry, matt and velvety, covered in fine papillae that repel water	Texture separates them instantly, and explains why one dries out and the other sheds water.
Head structures	No antennae and no image-forming eyes; a simple lobe over the mouth and light-sensitive skin cells	A pair of ringed antennae, a simple eye at the base of each, and a pair of slime papillae	A visible antenna pair rules out an earthworm on its own.
Diet and role	Detritivore, ingesting soil, leaf litter and decaying plant matter and passing it as casts	Predator of small invertebrates, immobilising prey with a sticky secretion fired from head papillae	One recycles dead material, the other sits above small invertebrates in the food web.
Gas exchange	Directly across the moist body wall, which is why drying out is quickly fatal	Through many small tracheal openings scattered over the body that cannot be closed	Neither can control water loss well, which confines both to damp conditions for different structural reasons.
Distribution	Worldwide in soils, including cultivated and heavily modified ground, with many introduced species	Restricted to humid tropical and southern temperate forests, in leaf litter and rotting logs	One is among the most widespread soil animals; the other is a narrowly distributed relict group.

Phylum: EarthwormAnnelida, the segmented worms, in the class Clitellata alongside leeches
Velvet WormOnychophora, a small phylum of roughly 200 described species related to arthropods
They are not distant cousins within one group; they belong to different phyla entirely.
Legs: EarthwormNone; movement uses waves of muscle contraction with tiny bristles gripping the burrow wall
Velvet WormMany paired stubby unjointed lobopods, each tipped with a pair of claws
Legs are the fastest diagnostic in the field, visible even in a poor photograph.Leg-pair counts differ by species, commonly falling somewhere between about 13 and 43 pairs.
Body surface: EarthwormMoist, slippery and shiny, with clear ring-like grooves marking true segments
Velvet WormDry, matt and velvety, covered in fine papillae that repel water
Texture separates them instantly, and explains why one dries out and the other sheds water.
Head structures: EarthwormNo antennae and no image-forming eyes; a simple lobe over the mouth and light-sensitive skin cells
Velvet WormA pair of ringed antennae, a simple eye at the base of each, and a pair of slime papillae
A visible antenna pair rules out an earthworm on its own.
Diet and role: EarthwormDetritivore, ingesting soil, leaf litter and decaying plant matter and passing it as casts
Velvet WormPredator of small invertebrates, immobilising prey with a sticky secretion fired from head papillae
One recycles dead material, the other sits above small invertebrates in the food web.
Gas exchange: EarthwormDirectly across the moist body wall, which is why drying out is quickly fatal
Velvet WormThrough many small tracheal openings scattered over the body that cannot be closed
Neither can control water loss well, which confines both to damp conditions for different structural reasons.
Distribution: EarthwormWorldwide in soils, including cultivated and heavily modified ground, with many introduced species
Velvet WormRestricted to humid tropical and southern temperate forests, in leaf litter and rotting logs
One is among the most widespread soil animals; the other is a narrowly distributed relict group.

How they are related

Earthworms are annelids, in the class Clitellata, which also contains leeches, and their body is built from repeated segments separated by internal walls. Velvet worms form the phylum Onychophora, roughly 200 described species in two families, and molecular and morphological work places them close to arthropods and tardigrades rather than to annelids. Their apparent segmentation is superficial, since the internal organs are not partitioned the way an annelid's are. Both names are used loosely for many species.

A note on naming: Both names cover many species. Earthworm is applied across several annelid families with different burrowing depths and habits, and velvet worm covers the whole phylum Onychophora, whose species differ in leg number, colour and reproduction, so figures here are ranges across the groups.

Telling them apart

Three cues settle it. Look for legs: an earthworm has none, a velvet worm has many pairs of soft clawed stubs. Look for antennae: only the velvet worm has a visible pair. Look at the surface: an earthworm is wet-looking and shiny with obvious ring grooves, while a velvet worm is dry, matt and finely pebbled, and often carries a pattern of dark bands or spots. Colour also differs, with velvet worms frequently blue, orange or deep green.

Legs and antennae decide it. No legs, no antennae, wet shiny skin, ring-marked body in soil: earthworm. Many soft clawed legs, a pair of antennae, dry velvety skin, often boldly coloured, in a rotting log in a humid forest: velvet worm. Geography helps too, since earthworms turn up in almost any garden while velvet worms are confined to specific forest regions and are rarely seen even where they occur.

Habitat and distribution

Earthworms occupy soils across most of the world, from garden beds and pasture to forest floors, and different ecological groups live at different depths, with some species remaining in leaf litter and others building deep permanent burrows. Velvet worms are confined to consistently humid places in tropical and southern temperate forests, sheltering inside rotting logs, under bark and in leaf litter, and their patchy distribution across South America, Africa, Australasia and Southeast Asia reflects ancient continental separation.

Diet and ecological role

An earthworm processes dead material, ingesting soil and decaying plant fragments, digesting the microbial and organic content and depositing the remainder as casts that alter soil structure and nutrient movement. A velvet worm takes live prey such as small insects, spiders and other litter invertebrates, immobilising them with a rapidly setting adhesive secretion released from the paired head papillae before feeding. The two therefore occupy completely different positions in the same leaf-litter system.

Behaviour

Earthworms are largely solitary and respond to vibration and light by withdrawing into the burrow, and some species surface at night to pull leaf fragments underground. Velvet worms are nocturnal and secretive, moving slowly on their lobopods and relying on antennal touch and chemical cues to detect prey. Several species show notable social behaviour, with reports of groups sharing shelters and maintaining dominance relationships around food, which is unusual among terrestrial invertebrates.

Senses and adaptations

Earthworms have no eyes but carry light-sensitive cells in the skin, especially near the front, and they are highly responsive to vibration and moisture gradients. Velvet worms carry a simple eye at the base of each antenna, sufficient for detecting light rather than resolving images, and depend mainly on antennal touch and chemoreception. Their most distinctive adaptation is the paired slime papillae, which can fire two jets of adhesive that set within seconds and are later reabsorbed by the animal.

More on this topic: Animal senses and adaptations.

Lifespan and life stages

Reported lifespans are longer than the small size suggests, but figures are patchy for both groups. Earthworm species in protected conditions have been recorded living several years, with far shorter survival in the field because of predation and cultivation. Velvet worms are thought to live for a year or more, and many species are viviparous or ovoviviparous, producing small numbers of well-developed young rather than large clutches. Captive records exceed field estimates for both, as usual.

People and these animals

Earthworms are among the most studied soil animals, valued in agriculture and composting for their effect on soil structure, and also monitored as invasive species where introduced worms alter forest floors that evolved without them. Velvet worms are of scientific interest for what they reveal about early arthropod evolution, and several species have restricted ranges dependent on undisturbed humid forest and rotting timber, which makes habitat clearance the main pressure on them.

Keeping them: what to understand first

Earthworms are kept in enormous numbers in wormeries and composting systems, and velvet worms are occasionally held by specialist invertebrate keepers, in some regions under collection restrictions. Keeping any animal depends on local law, welfare capacity, the humidity and shelter a keeper can sustain, and long-term responsibility, and questions about the health of a kept invertebrate belong with a qualified veterinarian. Nothing here recommends collecting either animal from the wild.

What they have in common

Both have long soft bodies without a hard external skeleton over most of their length.
Both are confined to damp microhabitats and lose water quickly in dry air.
Both live in soil and leaf litter and move through crevices in decaying material.
Both are mostly active at night or after rain and are rarely seen in the open by day.

Key differences

Earthworms are annelids; velvet worms belong to the separate phylum Onychophora.
Earthworms have no legs, while velvet worms walk on many pairs of clawed lobopods.
Only the velvet worm has antennae and simple eyes at their bases.
Earthworm skin is moist and slippery; velvet worm skin is dry and velvety with fine papillae.
Earthworms are detritivores that process soil, whereas velvet worms are predators of small invertebrates.
Earthworms are near-global in distribution; velvet worms are restricted to humid forest regions.

Where people go wrong

Calling a velvet worm a caterpillar, which has jointed thoracic legs and fleshy prolegs rather than uniform clawed lobopods.
Assuming any long soft-bodied animal with rings is an annelid, when velvet worm rings are cuticular folds rather than true segments.
Treating the velvet worm's slime as venom, when it is an adhesive and a separate saliva does the digesting.

Frequently asked questions

Are velvet worms related to earthworms at all?

No, they sit in different phyla. Earthworms are annelids, sharing a lineage with leeches and marine bristle worms. Velvet worms form the phylum Onychophora and current evidence places them close to arthropods and tardigrades. The shared long soft body is convergence on a way of moving through litter and crevices, and the internal anatomy differs substantially, particularly in how the body cavity and segmentation are organised.

What is the sticky slime a velvet worm produces?

It is a protein-rich adhesive stored in glands and fired as two jets from the papillae beside the mouth. It sets within seconds in air and entangles small invertebrate prey. The animal reclaims material from the dried slime afterwards, which matters because producing a full charge is costly and takes time to replace. It is an adhesive rather than a venom, although a separate saliva is used once the prey is secured.

Why does a velvet worm look segmented if it is not a true annelid?

The rings on the surface are folds and papillae in the cuticle rather than divisions of the body cavity. In an earthworm the segments are real, with internal walls separating fluid-filled compartments that give precise local control over shape. A velvet worm has one continuous body cavity, so it moves by changing internal pressure across the whole body while the lobopods do the walking, which produces its characteristic slow gliding gait.

Where would I actually find a velvet worm compared with an earthworm?

Earthworms occur in almost any soil with moisture and organic matter, including gardens, fields and roadside verges across most continents. Velvet worms are confined to humid tropical and southern temperate forests in South America, Africa, Australasia and parts of Southeast Asia, inside rotting logs and deep litter, and they are nocturnal and cryptic. Encountering one is a matter of being in the right forest and looking in decaying wood after rain.

Do velvet worms and earthworms have the same problem with drying out?

Both are restricted to damp conditions, but for different reasons. An earthworm exchanges gases across its moist skin, so drying stops respiration directly. A velvet worm breathes through numerous tracheal openings scattered across the body that cannot be closed, so water escapes continuously through them. That constraint is a large part of why onychophorans never spread beyond consistently humid habitats despite being an ancient lineage.

Read the full profiles

Sources and methodology

How this comparison is built: FaunaHub comparisons are assembled from the sourced animal profiles behind them rather than written as standalone claims. Figures such as size, mass, and lifespan are typical ranges that vary by subspecies, population, region, sex, age, and — where relevant — whether an animal lives in the wild or under human care, so they are presented as ranges rather than fixed values. Where a common name covers a group rather than a single species, the page says so instead of implying a species-to-species match. Conservation status changes over time and should be confirmed against the current IUCN Red List. Dimensions that could not be supported from the underlying profiles are omitted rather than filled in.

What this page does not do: it does not rank the two animals, predict the outcome of a confrontation, or present either one as stronger, smarter, or better. It is not veterinary, medical, first-aid, handling, capture, hunting, or pest-control guidance. For an animal in your care, or any situation involving injury, contact a qualified veterinarian, your local wildlife authority, or emergency services.

Sources and further reading

Authoritative references used for general educational context. External links open in a new tab. These sources do not endorse FaunaHub.

UniversityAnimal Diversity Web — University of Michigan Museum of Zoology — Peer-edited reference accounts for animal species
ReferenceBritannica — Earthworm — Editor-reviewed encyclopedia entry
Wildlife referenceIUCN Red List of Threatened Species — Authoritative source for current conservation status
ReferenceBritannica — Velvet worm (Onychophora) — Editor-reviewed encyclopedia entry
ReferenceEncyclopaedia Britannica — Animals reference — Editor-reviewed encyclopedia overview entries
Wildlife referenceSmithsonian's National Zoo & Conservation Biology Institute — Animals — Educational species pages from the Smithsonian Institution

Last updated: 2026-08-04