# Rough Keyhole Limpet (*diodora aspera*)

The Rough Keyhole Limpet is a small sea creature with a unique keyhole-shaped shell. It clings tightly to rocks in tidal pools, making it a fun find for little explorers!

- **Category:** [Invertebrate](https://www.snappit.app/explore/categories/invertebrate)
- **Rarity:** Common
- **Danger:** 1/5 · Very low
- **Snaps:** 1
- **Habitat:** They live in rocky coastal areas and tidal pools.
- **Also known as:** Diodora, Rough Limpet

![Rough Keyhole Limpet](https://commons.wikimedia.org/w/index.php?title=Special:Redirect/file/Diodora_aspera001.jpg&width=800)

Photo: Jan Delsing., Public domain · [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Diodora_aspera001.jpg)

## Appearance

The Rough Keyhole Limpet has a sturdy, cone-shaped shell, often grey or brownish, with prominent radial ribs. It is distinguished by a noticeable keyhole-shaped opening at its apex, which sets it apart from other limpet species.

## Taxonomy

- **Kingdom:** Animalia
- **Phylum:** Mollusca
- **Class:** Gastropoda
- **Order:** Lepetellida
- **Family:** Fissurellidae
- **Genus:** Diodora

## Interesting facts

- Its shell has a unique 'keyhole' opening, like a tiny skylight!
- Their tiny teeth are among the strongest natural materials on Earth!
- They glide along rocks on a slippery trail of mucus, like a super-slow surfer!
- This limpet's foot is so strong it can lift 50 times its own weight!

## Special abilities

- **Super Suction Foot:** Rough Keyhole Limpet has a powerful muscular foot that helps them cling tightly to rocks, even in strong waves, preventing them from being washed away.
- **Rock Scraper:** Rough Keyhole Limpet can graze algae from rocks using its specialized radula, a ribbon of tiny, super-hard teeth, to get its food.
- **Breathing Hole:** Rough Keyhole Limpet has a unique keyhole opening at its shell's top that lets out waste water and helps them breathe underwater!

## Measurements & details

- **Length:** 2-7 cm
- **Lifespan:** 5-15 years

## Diet & Feeding

This limpet is a vegetarian, grazing on tiny plants found on ocean rocks and other hard surfaces.

- **Primary Foods:** Microalgae, Diatoms, Algal films, Small seaweeds
- **Foraging Method:** Grazing

## Ecological connections

- **Eaten by:** [Ochre Sea Star](https://www.snappit.app/explore/ochre-sea-star) (*Pisaster ochraceus*) — A common predator in the intertidal zone.
- **Eaten by:** [Black Oystercatcher](https://www.snappit.app/explore/black-oystercatcher) (*Haematopus bachmani*) — Birds pry them off rocks with their strong beaks.
- **Eaten by:** Red Rock Crab (*Cancer productus*) — Crabs use their strong claws to crack limpet shells.

## Traits

- [Solitary](https://www.snappit.app/explore/traits/solitary): Solitary animals live alone for most of their lives, only interacting with others for mating or parental care.
- [Colorful](https://www.snappit.app/explore/traits/colorful): Colorful describes organisms or objects displaying a wide range of bright and distinct colors.
- [Herbivorous](https://www.snappit.app/explore/traits/herbivorous): This trait characterizes organisms whose diet consists entirely or primarily of plant material.
- [Coastal](https://www.snappit.app/explore/traits/coastal): Coastal habitats are dynamic environments located along the interface between land and sea, influenced by tides, waves, and saltwater.
- [Carnivorous](https://www.snappit.app/explore/traits/carnivorous): This trait identifies organisms whose diet consists entirely or primarily of animal tissue.
- [Marine](https://www.snappit.app/explore/traits/marine): Marine habitats encompass all saltwater environments of the Earth's oceans, supporting an immense diversity of aquatic life.

## Collections

- [Invertebrates](https://www.snappit.app/explore/collections/invertebrates)

## Safety

**Danger:** 1/5 · Very low

No special safety notes yet.

## Frequently Asked Questions

### How to identify Rough Keyhole Limpet?

Compare the overall shape, opening, spiral, ribs, hinge and surface sculpture. Beach shells often lose the colors and sharp edges they had on the living animal, so shape does most of the work. Seashell Identifier: upload a photo and compare the visible details.

### How long is Rough Keyhole Limpet?

2-7 cm

### How long does Rough Keyhole Limpet live?

5-15 years

### What does Rough Keyhole Limpet eat?

This limpet is a vegetarian, grazing on tiny plants found on ocean rocks and other hard surfaces.

### Where is Rough Keyhole Limpet usually found?

They live in rocky coastal areas and tidal pools.

### How does Rough Keyhole Limpet hunt?

Grazing

## Where to spot

- [Mendocino Coast Botanical Gardens](https://www.snappit.app/guides/places/mendocino-coast-botanical-gardens) — California, US · Botanical Garden
- [Myrtle Edwards Park](https://www.snappit.app/guides/places/myrtle-edwards-park) — Washington, US · Park

## More Invertebrate

- [Coral](https://www.snappit.app/explore/coral)
- [Crab Spider](https://www.snappit.app/explore/crab-spider) (*Mecaphesa asperata*)
- [Garden Spider](https://www.snappit.app/explore/garden-spider) (*Araneus diadematus*)
- [Brown Recluse Spider](https://www.snappit.app/explore/brown-recluse-spider) (*Loxosceles reclusa*)

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Source: [Rough Keyhole Limpet: Facts & Places to See — Snappit](https://www.snappit.app/explore/rough-keyhole-limpet)