Centipedes vs Silverfish: How to differentiate both

When it comes to household pests, centipedes and silverfish are two common insects that often cause confusion due to their similar habitats and appearance. Both prefer dark, damp environments like basements, bathrooms, and kitchens, but their behavior, diet, and risks to humans differ significantly. While centipedes are predators that help control other insects, silverfish are scavengers that can damage books, clothing, and food products. In this guide, we will learn how to identify, prevent, and manage both pests effectively.

What is a Centipede?

Centipedes are elongated, fast-moving arthropods known for their numerous legs and predatory nature. While their appearance may seem intimidating, they are actually beneficial insects as they prey on other household pests like cockroaches, spiders, and ants.

Physical Characteristics of Centipedes

Size: Varies by species, ranging from 1 inch to 6 inches in length.
Body Structure: Long, segmented body with numerous legs (up to 177 pairs in some species).
Color: Typically brown or reddish-brown, with a slightly flattened body.
Legs: Long, spindly legs, allowing them to move quickly.
Venom: Equipped with venomous claws behind their head to immobilize prey (not harmful to humans).

What is a Silverfish?

Silverfish are small, wingless insects that are known for their shimmering, fish-like movement. Unlike centipedes, silverfish are not predators but scavengers that feed on starchy materials, causing damage to paper, books, fabrics, and food products.

Physical Characteristics of Silverfish

Size: Smaller than centipedes, measuring 1/2 inch to 1 inch in length.
Body Structure: Flattened, elongated body with three long, tail-like appendages at the rear.
Color: Silvery-gray, often covered in shiny scales, giving them a metallic appearance.
Legs: Six short legs, often mistaken for other small insects.

Key Differences Between Centipedes and Silverfish

Feature	Centipedes	Silverfish
Size & Shape	Long, segmented body with numerous legs (1-6 inches)	Flat, elongated body with three long tail-like appendages (1/2 – 1 inch)
Color	Brown or reddish-brown	Silvery-gray with a metallic sheen
Legs	Many long legs (up to 177 pairs)	Six short legs
Movement	Fast-moving, runs quickly across surfaces	Slow-moving, wiggling fish-like motion
Diet	Carnivorous, preys on other insects	Feeds on starchy materials (paper, glue, fabric, food crumbs)
Habitat	Dark, moist areas like basements and bathrooms	Damp, humid areas like kitchens, attics, and bookshelves
Risk to Humans	Mild bite, but not dangerous; beneficial for pest control	No bite, but damages books, clothes, and food

How to Identify Centipedes and Silverfish?

Proper identification is key to determining how to manage infestations effectively. If you see a long, fast-moving insect with numerous legs, you are likely dealing with a centipede. If you spot a small, shiny insect with three tail-like appendages, it is likely a silverfish.

Identifying a Centipede

Legs: Look for numerous pairs of long, spindly legs.
Speed: Observe its speed—centipedes run quickly when disturbed.
Color: Check for reddish-brown or brown coloration.
Habitat: Found in damp areas, such as crawl spaces and under debris.

Identifying a Silverfish

Appearance: Look for a silvery-gray, metallic appearance.
Movement: Observe its slow, wiggling movement—it moves like a fish.
Body Features: Check for three long appendages at the rear of its body.
Habitat: Commonly found near bookshelves, stored papers, and humid areas.

How to Prevent Centipedes and Silverfish?

Taking preventative measures can help reduce infestations and eliminate the conditions that attract these pests. Since centipedes thrive in moist environments, reducing moisture levels is the best deterrent. Silverfish are drawn to starch-based materials, so eliminating food sources is key.

Preventing Centipedes

Seal entry points around windows, doors, and foundation cracks.
Reduce moisture by using dehumidifiers and fixing leaks.
Eliminate food sources by controlling other household pests that centipedes feed on.
Declutter basements and crawl spaces to remove potential hiding spots.

Preventing Silverfish

Block cracks and gaps in walls, windows, and cabinets.
Control humidity with dehumidifiers and improve ventilation.
Store edibles properly in airtight containers and avoid leaving food crumbs.
Keep books, papers, and fabrics stored in dry conditions to prevent damage.

How to Treat a Centipede or Silverfish Infestation?

If you discover an infestation, taking the right approach can help eliminate these pests quickly. Centipedes are beneficial predators, but if their numbers become excessive, control measures may be needed. Silverfish infestations can be persistent, especially in humid environments.

Dealing with Centipedes

Vacuum regularly to remove centipedes and their eggs.
Use insecticides in areas where centipedes are commonly found (basements, attics, bathrooms).
Install barriers like weather stripping around doors and windows.

Dealing with Silverfish

Vacuum frequently to remove silverfish and food sources.
Apply boric acid or diatomaceous earth in cracks and crevices.
Apply sticky traps near bookshelves, attics, and damp areas.
Contact a professional exterminator for severe infestations.

Myths and Facts About Silverfish and Centipedes

Myth	Fact
Centipedes are insects.	Centipedes are arthropods, but not true insects. They belong to the class Chilopoda.
Silverfish can cause allergic reactions.	Silverfish are not known to cause allergic reactions. They are primarily a nuisance pest.
All centipedes are venomous and dangerous.	While centipedes have venom, their bites are generally not dangerous to humans.
Silverfish are a sign of poor hygiene.	Silverfish are attracted to dry, undisturbed areas, not necessarily poor hygiene.
Centipedes can be found in dry environments.	Centipedes prefer moist and dark environments.