What do fleas look like?

Adults are small (about 2–3 mm), reddish-brown to black, flattened sideways, with no wings and long jumping legs. Cat and dog fleas have combs (ctenidia) on the head and pronotum; human flea has none. Eggs are tiny and white; larvae are worm-like and pale; pupae are in cocoons in the environment.

How do I know if I have fleas?

Look for flea dirt (black specks on the pet or bedding that turn reddish when wet), live fleas on the pet or jumping in the home, and bites on ankles or legs. Use a flea comb and damp paper to confirm flea dirt.

Cat flea or dog flea?

Cat flea is much more common, including on dogs. Under magnification, cat flea has a gently sloping head profile; dog flea has a more convex head. For control, treatment is the same — treat pet and environment.

Why do I have flea bites but no pets?

Fleas can be brought in by previous occupants, wildlife, or visitors’ pets. Human flea is another possibility. Professional treatment of the environment and sealing entry points can help.

How do I use the quick comparison table?

Match what you see (size, colour, where found, whether on cat/dog/human) to the table. Cat flea is most likely. Then read the species card for life stages, signs, and when to get help. Always treat pet and environment together.

Flea Identification Guide

Q: When should I get professional help?

When infestation is heavy, in multiple rooms, or when DIY and pet treatment have not worked. Professional environmental treatment targets eggs, larvae, and adults; coordinate with your vet for the pet.

Fleas are small, jumping, blood-feeding insects that infest pets and homes. In South Africa the cat flea is by far the most common — on both cats and dogs — and it will bite humans too. Correct identification of the flea type and life stage helps you target treatment: adults on the host and in the environment, plus eggs, larvae, and pupae in carpets, bedding, and cracks. This guide covers what fleas look like, where you find them, key signs, and when to get professional help.

Identify cat flea, dog flea, and human flea. Know life stages, flea dirt, bites, and where they breed.

Need help with fleas?

Call National flea methodology

Adult pointing out fleas on a dog bed — identification guide context; species cards below show close-up ID photos

How to use this guide

Check whether you see adults (small, dark, jumping) or signs only — flea dirt, eggs, larvae.
Note where — on the pet, in carpets, pet bedding, upholstery, or cracks.
Look at the host — cat flea is common on both cats and dogs; dog flea is rarer; human flea has no combs.
Recognise life stages — adult (2–3 mm, flattened), egg (tiny white), larva (worm-like), pupa (cocoon).
Confirm with flea dirt — black specks that turn reddish when wet (digested blood).
Then match to the species card and use the quick comparison table; treat pet and environment together.

Quick comparison

Flea	Colour	Size	Commonly found	Key clue
Cat flea	Reddish-brown to black	~2–3 mm adult	Pets (cats and dogs), carpets, pet bedding, upholstery	Most common; jumps; bites humans; combs on head and pronotum
Dog flea	Reddish-brown to black	Similar to cat flea	Dogs mainly; same environments as cat flea	Rarer; convex head profile; similar biology
Human flea	Brown to dark	~2–4 mm	Humans; pigs; sometimes bedding and floors	No genal or pronotal combs; different host preference

Species at a glance

Use the cards below to match what you see — appearance, where they are found, and behaviour.

Cat Flea

Ctenocephalides felis

Appearance

Adult: small, flattened sideways, reddish-brown to black; about 2–3 mm
No wings; long hind legs for jumping; genal and pronotal combs (ctenidia)
Head profile gently sloping (distinguishes from dog flea under magnification)
Eggs: tiny white ovals, often in fur and where pets rest
Larvae: worm-like, pale, avoid light; in carpets, cracks, and bedding
Pupae: in cocoons; can wait weeks to emerge as adults

Commonly found

On cats and dogs (most common flea on both)Carpets and rugsPet bedding and basketsUpholstery and sofasCracks in floors and skirtingUnder furnitureVehicles where pets travel

Behaviour

The dominant flea in South African homes and on pets. Adults feed on blood; females lay eggs that fall off the host. Larvae feed on organic debris and flea dirt (faeces); pupae can remain dormant for weeks. Entire life cycle can complete in about two weeks in warm conditions. Cat fleas readily bite humans, especially on ankles and legs. Control requires treating both the pet (with vet-recommended products) and the environment.

Why you may be seeing them

Pets bring fleas indoors; eggs and larvae build up in carpets and resting areas. Warmth and humidity favour rapid development. Flea dirt (black specks that turn red when wet), pets scratching, and bites on people are common signs. Often worse in summer but can occur year-round in heated homes.

Often confused with

Dog flea (very similar; head shape differs under magnification; much rarer) · Human flea (no combs; different host preference) · Other small jumping insects (e.g. springtails — not blood-feeders)

When to get help

Heavy infestation; fleas or flea dirt in multiple rooms; bites on people; or when pet and home treatment together have not worked. Professional environmental treatment plus coordinated vet treatment breaks the cycle.

In southern Africa the cat flea is usually the species responsible for flea problems in homes. Both C. felis felis and C. felis strongylus occur in South Africa.

Cat flea pest guide — lifecycle, cocoon staging & myths Need help with fleas? See Flea Control Cape Town

Dog Flea

Ctenocephalides canis

Appearance

Adult: very similar to cat flea; reddish-brown to black; ~2–3 mm
Pronotal and genal combs present
Head profile more convex than cat flea (identification under magnification)
Eggs, larvae, and pupae similar to cat flea

Commonly found

Mainly on dogs (but cat flea is often found on dogs too)Same environments as cat flea when presentKennels, yards, and pet resting areas

Behaviour

Less common than cat flea in most areas; dogs are often infested with cat fleas instead. Biology similar: eggs fall off host, larvae develop in environment, pupae can delay emergence. Same need to treat pet and environment.

Why you may be seeing them

If you have dogs and see fleas, they may be dog or cat fleas; cat flea is more likely. Same signs: flea dirt, scratching, bites. Treatment approach is the same.

Often confused with

Cat flea (most common; head shape differs slightly) · Human flea (no combs)

When to get help

Same as cat flea — professional environmental treatment and vet-recommended pet treatment.

Dog flea is relatively rare compared to cat flea; identification to species is mainly for records. Control is the same.

Dog flea pest guide — true C. canis vs “fleas on dogs”Need help with fleas? See Flea Control Cape Town

Human Flea

Pulex irritans

Appearance

Adult: brown to dark; about 2–4 mm; no wings
No genal or pronotal combs (unlike cat and dog flea)
Flattened laterally; strong jumper

Commonly found

Historically associated with humans and pigsBedding, floors, and living areasLess common in modern homes than cat flea

Behaviour

Can bite humans and other hosts. Lacks the combs (ctenidia) that cat and dog fleas have, so under magnification it is distinguishable. In many areas cat flea has become the main flea biting humans in homes with pets.

Why you may be seeing them

May appear in homes without pets or in association with other hosts. If you see fleas and have no pets, or fleas do not match cat/dog flea, human flea is a possibility. Less common than cat flea in South African households.

Often confused with

Cat flea (has combs) · Dog flea (has combs)

When to get help

Environmental treatment and personal/bedding hygiene; professional treatment if infestation persists.

Identification by absence of combs. Control still requires treating the environment and any relevant hosts.

Human flea pest guide — Pulex irritans myths & host flexibility Need help with fleas? See Flea Control Cape Town

Common signs by location

Where you find fleas, flea dirt, or bites — on the pet, in carpets, bedding, or on people — points to the species and life stages. Use this to target treatment.

On the pet (coat, skin)
Adults and flea dirt (black specks). Use a flea comb; place debris on damp paper — if it turns reddish, it is flea dirt. Pets scratch and bite at coat.
Cat fleaDog flea
Pet bedding and baskets
Eggs, larvae, and flea dirt accumulate. Wash at high temperature and treat with pet-safe products.
Cat fleaDog flea
Carpets and rugs
Eggs fall here; larvae develop in the pile and under furniture. Vacuum thoroughly and treat with products that target eggs and larvae.
Cat fleaDog flea
Sofas and upholstery
Where pets rest. Eggs and larvae in seams and crevices. Treat as part of full environment.
Cat fleaDog flea
Floor cracks and skirting
Larvae and pupae in cracks. Hard to reach with vacuum; insect growth regulators and residual products help.
Cat fleaDog flea
Ankles and lower legs (bites)
Flea bites often on ankles; small red bumps, sometimes in groups. Bites alone do not confirm species; look for fleas or flea dirt.
Cat fleaDog fleaHuman flea

Why fleas keep coming back

Life cycle not broken — eggs, larvae, and pupae in the environment produce new adults; treat all stages.
Pet not treated or not treated long enough — adults on the pet keep laying eggs; coordinate with vet.
Pupae emerging later — pupae are resistant; new adults can appear weeks after treatment; follow-up may be needed.
Untreated zones — under furniture, in cracks, or in the car; full environment treatment is required.
Reintroduction — other pets, wildlife, or visiting animals can bring fleas back; ongoing prevention helps.
Warmth and humidity — fleas develop faster in ideal conditions; reducing humidity and thorough treatment help.

Common flea signs and behaviour

These patterns help you confirm fleas and target both pet and environment.

Flea dirt on pet or bedding
Black specks (faeces) that turn reddish when wiped with damp tissue — digested blood. Confirms flea presence. Comb the pet and check bedding and carpets.
Pet scratching and biting
Frequent scratching, especially around neck, base of tail, and belly. Can cause hair loss and skin irritation. Check for fleas and flea dirt.
Tiny jumping insects
Adults are small, dark, and jump when disturbed. Hard to catch; use a flea comb on the pet or look on white bedding/surfaces.
Bites on ankles and legs
Small red bumps, often in groups; can itch. Fleas bite exposed skin. Not all bite reactions are fleas — confirm with flea dirt or sighting.
Eggs and larvae in the home
Eggs are tiny white ovals; larvae are worm-like and avoid light. Found in carpets, under furniture, and in pet resting areas. Need environmental treatment.
New fleas weeks after treatment
Pupae can wait to emerge. Follow-up treatment or ongoing vacuuming and product application may be needed to break the cycle fully.

When to get professional help

Heavy flea infestation on pets or in the home
Flea dirt or fleas in multiple rooms
Bites on people that suggest ongoing infestation
Previous DIY or single treatment did not stop the problem
You want full environment treatment plus advice on pet treatment
Commercial premises or rental property with flea complaints

Call Get flea control

Ready to break the flea cycle?

Professional environment treatment plus coordinated pet treatment — so fleas don’t keep coming back.

Call Flea Control Cape Town

Flea Identification Guide

Identify cat flea, dog flea, and human flea. Know life stages, flea dirt, bites, and where they breed.

How to use this guide

Check whether you see adults (small, dark, jumping) or signs only — flea dirt, eggs, larvae.

Note where — on the pet, in carpets, pet bedding, upholstery, or cracks.

Look at the host — cat flea is common on both cats and dogs; dog flea is rarer; human flea has no combs.

Recognise life stages — adult (2–3 mm, flattened), egg (tiny white), larva (worm-like), pupa (cocoon).

Confirm with flea dirt — black specks that turn reddish when wet (digested blood).

Then match to the species card and use the quick comparison table; treat pet and environment together.

Quick comparison

Flea	Colour	Size	Commonly found	Key clue
Cat flea	Reddish-brown to black	~2–3 mm adult	Pets (cats and dogs), carpets, pet bedding, upholstery	Most common; jumps; bites humans; combs on head and pronotum
Dog flea	Reddish-brown to black	Similar to cat flea	Dogs mainly; same environments as cat flea	Rarer; convex head profile; similar biology
Human flea	Brown to dark	~2–4 mm	Humans; pigs; sometimes bedding and floors	No genal or pronotal combs; different host preference

Cat Flea

Ctenocephalides felis

Appearance

Adult: small, flattened sideways, reddish-brown to black; about 2–3 mm
No wings; long hind legs for jumping; genal and pronotal combs (ctenidia)
Head profile gently sloping (distinguishes from dog flea under magnification)
Eggs: tiny white ovals, often in fur and where pets rest
Larvae: worm-like, pale, avoid light; in carpets, cracks, and bedding
Pupae: in cocoons; can wait weeks to emerge as adults

Commonly found

On cats and dogs (most common flea on both)Carpets and rugsPet bedding and basketsUpholstery and sofasCracks in floors and skirtingUnder furnitureVehicles where pets travel

Behaviour

Why you may be seeing them

Often confused with

Dog flea (very similar; head shape differs under magnification; much rarer) · Human flea (no combs; different host preference) · Other small jumping insects (e.g. springtails — not blood-feeders)

When to get help

In southern Africa the cat flea is usually the species responsible for flea problems in homes. Both C. felis felis and C. felis strongylus occur in South Africa.

Cat flea pest guide — lifecycle, cocoon staging & myths Need help with fleas? See Flea Control Cape Town

Common signs by location

Where you find fleas, flea dirt, or bites — on the pet, in carpets, bedding, or on people — points to the species and life stages. Use this to target treatment.

On the pet (coat, skin)

Adults and flea dirt (black specks). Use a flea comb; place debris on damp paper — if it turns reddish, it is flea dirt. Pets scratch and bite at coat.

Cat fleaDog flea

Pet bedding and baskets

Eggs, larvae, and flea dirt accumulate. Wash at high temperature and treat with pet-safe products.

Cat fleaDog flea

Carpets and rugs

Eggs fall here; larvae develop in the pile and under furniture. Vacuum thoroughly and treat with products that target eggs and larvae.

Cat fleaDog flea

Sofas and upholstery

Where pets rest. Eggs and larvae in seams and crevices. Treat as part of full environment.

Cat fleaDog flea

Floor cracks and skirting

Larvae and pupae in cracks. Hard to reach with vacuum; insect growth regulators and residual products help.

Cat fleaDog flea

Ankles and lower legs (bites)

Flea bites often on ankles; small red bumps, sometimes in groups. Bites alone do not confirm species; look for fleas or flea dirt.

Cat fleaDog fleaHuman flea

Why fleas keep coming back

Life cycle not broken — eggs, larvae, and pupae in the environment produce new adults; treat all stages.

Pet not treated or not treated long enough — adults on the pet keep laying eggs; coordinate with vet.

Pupae emerging later — pupae are resistant; new adults can appear weeks after treatment; follow-up may be needed.

Untreated zones — under furniture, in cracks, or in the car; full environment treatment is required.

Reintroduction — other pets, wildlife, or visiting animals can bring fleas back; ongoing prevention helps.

Warmth and humidity — fleas develop faster in ideal conditions; reducing humidity and thorough treatment help.

Common flea signs and behaviour

These patterns help you confirm fleas and target both pet and environment.

Flea dirt on pet or bedding

Black specks (faeces) that turn reddish when wiped with damp tissue — digested blood. Confirms flea presence. Comb the pet and check bedding and carpets.

Pet scratching and biting

Frequent scratching, especially around neck, base of tail, and belly. Can cause hair loss and skin irritation. Check for fleas and flea dirt.

Tiny jumping insects

Adults are small, dark, and jump when disturbed. Hard to catch; use a flea comb on the pet or look on white bedding/surfaces.

Bites on ankles and legs

Small red bumps, often in groups; can itch. Fleas bite exposed skin. Not all bite reactions are fleas — confirm with flea dirt or sighting.

Eggs and larvae in the home

Eggs are tiny white ovals; larvae are worm-like and avoid light. Found in carpets, under furniture, and in pet resting areas. Need environmental treatment.

New fleas weeks after treatment

Pupae can wait to emerge. Follow-up treatment or ongoing vacuuming and product application may be needed to break the cycle fully.

When to get professional help

Heavy flea infestation on pets or in the home

Flea dirt or fleas in multiple rooms

Bites on people that suggest ongoing infestation

Previous DIY or single treatment did not stop the problem

You want full environment treatment plus advice on pet treatment

Commercial premises or rental property with flea complaints

Flea Identification Guide

How to use this guide

Quick comparison

Species at a glance

Appearance

Commonly found

Behaviour

Why you may be seeing them

Often confused with

When to get help

Appearance

Commonly found

Behaviour

Why you may be seeing them

Often confused with

When to get help

Appearance

Commonly found

Behaviour

Why you may be seeing them

Often confused with

When to get help

Common signs by location

On the pet (coat, skin)

Pet bedding and baskets

Carpets and rugs

Sofas and upholstery

Floor cracks and skirting

Ankles and lower legs (bites)

Why fleas keep coming back

Common flea signs and behaviour

Flea dirt on pet or bedding

Pet scratching and biting

Tiny jumping insects

Bites on ankles and legs

Eggs and larvae in the home

New fleas weeks after treatment

When to get professional help

Related pages

Ready to break the flea cycle?

Flea Identification Guide

How to use this guide

Quick comparison

Species at a glance

Appearance

Commonly found

Behaviour

Why you may be seeing them

Often confused with

When to get help

Appearance

Commonly found

Behaviour

Why you may be seeing them

Often confused with

When to get help

Appearance

Commonly found

Behaviour

Why you may be seeing them

Often confused with

When to get help

Common signs by location

On the pet (coat, skin)

Pet bedding and baskets

Carpets and rugs

Sofas and upholstery

Floor cracks and skirting

Ankles and lower legs (bites)

Why fleas keep coming back

Common flea signs and behaviour

Flea dirt on pet or bedding

Pet scratching and biting

Tiny jumping insects

Bites on ankles and legs

Eggs and larvae in the home

New fleas weeks after treatment

When to get professional help

Related pages

Ready to break the flea cycle?