Flea Larvae

what a flea larva looks like under a microscope

Kalumet

Img 1 Flea larva with a transparent body and red digestive track from consuming blood feces. View more pictures.

This page provides a quick summary of flea larvae, in the form of a FAQ. Click on the answers for detailed information, including citations.

What do flea larvae look like?
Flea larvae look like bristly, segmented worms. They’re 2-5 mm long and off-white. Their bodies are translucent, so their red guts are visible once feeding begins. They have no eyes or legs.

Are flea larvae black?
Their dark red guts can appear black from a distance.

Where do flea larvae live?
The larvae live where eggs fall into the environment. To survive they require dark, humid, food-rich habitats. In homes, most larvae live within carpets, where they burrow to the base to avoid light.

Do flea larvae live in pet poop?
No. Worms in pet feces may be roundworms, tapeworms, hookworms, or whipworms.

How far can flea larvae travel?
They rarely travel further than 20 cm from where they hatch.

How long do flea larvae live?
In homes, flea larvae mature in 7-11 days and then pupate. In poor conditions (cool and dry), it may take 28-45 days. Beyond this, when conditions get too harsh, the larvae perish.

Do flea larvae molt?
Flea larvae develop through 3 stages, called instars. They molt once between each stage (twice total). Shedding their cuticle allows for growth.

What do flea larvae eat?
The larvae eat adult flea feces (flea dirt) and other flea eggs. They don’t consume environmental debris, as was once believed.

How long does it take larvae to starve?
They’ll die within 3 days without food.

Do flea larvae bite?
No. They aren’t parasitic. They are free-living organisms that graze for food in their off-host habitat.

What percent of infestations are larvae?
Larvae make up 34-35% of flea infestations.

Does vacuuming kill flea larvae?
Larvae are somewhat protected at the base of carpets. Still, vacuuming can remove 15-50% from carpeting. 100% of those removed will die in the process.

Do flea larvae drown?
Flea larvae will quickly drown in wet environments. Water also dissolves flea dirt, which the larvae need for food.

What’s the best way to get rid of fleas?
Please see our page on How to get rid of fleas for control information. Effective techniques to kill larvae include vacuuming, laundering, and using insect growth regulators.

Please leave a comment below if you have any questions that weren’t addressed, and I’ll add them to the list.

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  • jim morrison June 28, 2017, 8:36 am

    Have a young hedgehog infested with fleas – and ticks – but is blinded by flea larvae wanting to enter the eyes, ears and nostrils. I mean thousands of them, all clustered around the eyes, in particular. If they consume adult droppings, why are they seemingly obsessed with the eyes. Could it be a desire for moisture? Have removed physically, but the youngster is in a sorry state.

    • Adam Retzer July 2, 2017, 12:51 pm

      Jim, unfortunately I don’t know much about hedgehog fleas (Archaeopsylla erinacei). It’s a different species from those that affect dogs and cats, which this site is focused on. Hedgehog fleas may have different behaviors and habitats, I am not certain. I’d recommend contacting your veterinarian. Sorry I can’t offer more help at this point.

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