What Kind of Bug Is This? Common Bug Groups

Is It a Louse? How to Tell Lice From Look-Alikes

Lice: 4 marks to check, what they are often confused with, whether they bite or sting, and where they turn up, quoted from university entomology and IPM sources.

These pages help you narrow a bug down to its group from what you can see. They are not medical advice. Seek medical care promptly for severe symptoms or any sign of an allergic reaction.

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At a glance

Group: Lice belong to the order Phthiraptera; the three types commonly found on humans are head lice, body lice, and pubic lice, all external parasitic insects.
Body plan: Adults are about 1/12 to 1/8 inch long, with six legs bearing claws for grasping hair; adults are wingless; the abdomen is longer than it is wide, and body color ranges from dirty white to grayish-black (depending on host hair color). The source does not describe antenna shape.
Size: Adult head lice are roughly 2-3 mm long, about the size of a sesame seed; adult body lice are about 2.3-3.6 mm long, a similar size.
Bites or stings: Lice feed on human blood, and bites cause itching from an allergic reaction; head lice do not transmit disease, but body lice can spread epidemic typhus, Bartonella quintana infection (trench fever), and epidemic relapsing fever.
Where you find them: Head lice live on the scalp/hair (also found on eyebrows and eyelashes); body lice do not attach directly to skin but live and lay eggs on the clothing and bedding of infested people; pubic lice are found in pubic/genital-area hair.

How to tell it is one of the lice

Lice can only crawl; they cannot hop or fly, unlike fleas, which are strong jumpers.
Head lice live exclusively among the hairs on the head and do not leave the host for carpets or bed crevices the way fleas or bed bugs do.
Body lice do not live directly on the skin but live and lay eggs on the clothing and bedding used by infested people — a key difference from head lice and pubic lice.
Louse eggs (nits) are oval, grayish-white to tan, firmly glued to the base of hair or fabric fibers, and about 1/32 inch (1 mm) long — useful for identification.

Often confused with

People most often mix lice up with:

Open the other page and compare its list against the marks above; the differences are usually in the antennae, wings or the way the body is divided.

Bites and stings

Lice feed on human blood, and bites cause itching from an allergic reaction; head lice do not transmit disease, but body lice can spread epidemic typhus, Bartonella quintana infection (trench fever), and epidemic relapsing fever. Seek medical care promptly for severe symptoms or any allergic reaction.

Pest or beneficial?

The source explicitly states head lice do not transmit disease and are not considered a health hazard, just a common itch-causing parasitic problem; no beneficial ecological or agricultural role is described for lice.

Where they turn up

Head lice live on the scalp/hair (also found on eyebrows and eyelashes); body lice do not attach directly to skin but live and lay eggs on the clothing and bedding of infested people; pubic lice are found in pubic/genital-area hair.

How to photograph it for identification

Get as close as your camera will focus, from directly above, in daylight or a bright lamp. Include the whole body with the legs and antennae in frame; a second shot from the side shows wings and body segments. Put a coin or ruler next to it for scale. For a bite or a bug found on skin or bedding, photograph the bug itself, not the mark. The app names the likely group; use the list above to confirm.

FAQ

Do lice bite or sting?

What is the quickest way to recognize lice?

Lice can only crawl; they cannot hop or fly, unlike fleas, which are strong jumpers.

Are lice a pest?

How do I tell lice from fleas?

Lice can only crawl; they cannot hop or fly, unlike fleas, which are strong jumpers. Body lice do not live directly on the skin but live and lay eggs on the clothing and bedding used by infested people — a key difference from head lice and pubic lice. The Fleas page lists its own marks.

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