Crabs & Hermit Crabs

American Pebble Crab

Daira americana is a small shore crab associated with rocky lower tidal habitat.

Calcinus Hermit Crab

Calcinus obscurus is a marine hermit crab.

Halloween Land Crab

Gecarcinus quadratus is a land crab associated with coastal habitats.

Mottled Shore Crab

Pachygrapsus transversus is a small shore crab that uses rocky intertidal habitat.

Pacific Ghost Crab

Ocypode gaudichaudii is a Pacific ghost crab associated with sandy beaches.

Pacific Land Hermit Crab

Coenobita compressus is a land hermit crab whose adult life is spent on land near the coast.

Panama Hermit Crab

Clibanarius panamensis is a marine hermit crab documented in Costa Rican coastal collections.

Rough-clawed Rock Crab

Eriphia squamata is a shore crab with a broad, roughly hexagonal carapace and conspicuously textured claws.

Sally Lightfoot Crab

Grapsus grapsus is a crab associated with rocky shores.

Nature Field Guide

American Pebble Crab

Spanish name: Cangrejo piedra americano
Scientific name: Daira americana

What Do Pico & Tati Think?

A crab can blend into a rocky neighborhood. Pico watches patiently while Tati compares the outline with the stones around it.

Identification

Key Features of the American Pebble Crab

A compact crab body
A textured carapace
Confirm the identification from a detailed photograph

Habitat & range

Rocky shore and naturally visible tidal habitat. Choose a permitted observation point with an adult; do not turn rocks or reach into holes.

Conservation & care

Give claws and burrow entrances space. Do not handle, feed, chase or collect crabs. Leave rocks and shells where they are, and follow your adult’s route and local signs.

Nature Field Guide

Calcinus Hermit Crab

Spanish name: Cangrejo ermitaño Calcinus
Scientific name: Calcinus obscurus

Coastal Life · Crabs & Hermit Crabs · Marine Life Rocky Shore

What Do Pico & Tati Think?

Pico thinks a shell has moved. Tati waits until a small leg appears before writing down what she has seen.

Identification

Key Features of the Calcinus Hermit Crab

A marine hermit crab in a borrowed shell
Visible legs and claws at the shell opening
The shell species and crab species are separate identifications

Habitat & range

Rocky shore and naturally visible tidal habitat. Choose a permitted observation point with an adult; do not turn rocks or reach into holes.

Conservation & care

Give claws and burrow entrances space. Do not handle, feed, chase or collect crabs. Leave rocks and shells where they are, and follow your adult’s route and local signs.

Nature Field Guide

Halloween Land Crab

Spanish name: Cangrejo arlequín
Scientific name: Gecarcinus quadratus

Coastal Life · Crabs & Hermit Crabs · Marine Life Estuary & Mangroves · Forest Edge

What Do Pico & Tati Think?

Not every coastal crab lives underwater. Pico and Tati look at the ground beside the path without leaving it.

Identification

Key Features of the Halloween Land Crab

A crab walking on land near coastal vegetation
Burrows may be present in suitable ground
Confirm the species from the whole animal, not a burrow alone

Habitat & range

Coastal vegetation and adjacent ground. Stay on established routes and do not search inside burrows.

Conservation & care

Give claws and burrow entrances space. Do not handle, feed, chase or collect crabs. Leave rocks and shells where they are, and follow your adult’s route and local signs.

Nature Field Guide

Mottled Shore Crab

Spanish name: Cangrejo costero moteado
Scientific name: Pachygrapsus transversus

Coastal Life · Crabs & Hermit Crabs · Marine Life Rocky Shore

What Do Pico & Tati Think?

Pico waits for a small movement between rocks. Tati records the difference between a hiding place and a feeding place.

Identification

Key Features of the Mottled Shore Crab

A small crab on rocky shore
Look for movement near existing crevices
Use a verified photograph to compare markings and body proportions

Habitat & range

Rocky shore and naturally visible tidal habitat. Choose a permitted observation point with an adult; do not turn rocks or reach into holes.

Conservation & care

Give claws and burrow entrances space. Do not handle, feed, chase or collect crabs. Leave rocks and shells where they are, and follow your adult’s route and local signs.

Nature Field Guide

Pacific Ghost Crab

Spanish name: Cangrejo fantasma del Pacífico
Scientific name: Ocypode gaudichaudii

Coastal Life · Crabs & Hermit Crabs · Marine Life Beach

What Do Pico & Tati Think?

A tiny trail across the sand gives Pico a clue. Tati wonders whether the animal is nearby or hidden below.

Identification

Key Features of the Pacific Ghost Crab

A crab moving over beach sand
Eyes carried above the body on stalks
Tracks and burrows are clues but not proof of species

Habitat & range

Sandy beach above the wash of the waves. Observe tracks and any naturally visible crabs from a distance.

Conservation & care

Give claws and burrow entrances space. Do not handle, feed, chase or collect crabs. Leave rocks and shells where they are, and follow your adult’s route and local signs.

Nature Field Guide

Pacific Land Hermit Crab

Spanish name: Cangrejo ermitaño terrestre del Pacífico
Scientific name: Coenobita compressus

Coastal Life · Crabs & Hermit Crabs · Marine Life Beach · Forest Edge

What Do Pico & Tati Think?

Pico calls it a traveling home. Tati remembers that an apparently empty shell may already belong to a crab.

Identification

Key Features of the Pacific Land Hermit Crab

A hermit crab walking on land
A shell carried over the abdomen
Visible legs and claws can retreat inside the opening

Habitat & range

Coastal vegetation and adjacent ground. Stay on established routes and do not search inside burrows.

Conservation & care

Adults are adapted to life on land. Do not place the crab in water, remove its shell, collect it or keep it as a pet. Leave coastal shelters undisturbed.

Nature Field Guide

Panama Hermit Crab

Spanish name: Cangrejo ermitaño panameño
Scientific name: Clibanarius panamensis

Coastal Life · Crabs & Hermit Crabs · Marine Life Estuary & Mangroves · Rocky Shore

What Do Pico & Tati Think?

A shell can be both a clue and a hiding place. Pico and Tati practice patience while its resident decides whether to appear.

Identification

Key Features of the Panama Hermit Crab

Legs or claws extending from a shell
An animal carrying the shell as it moves
Check the crab’s features with a specialist reference

Habitat & range

Rocky shore and naturally visible tidal habitat. Choose a permitted observation point with an adult; do not turn rocks or reach into holes.

Conservation & care

Give claws and burrow entrances space. Do not handle, feed, chase or collect crabs. Leave rocks and shells where they are, and follow your adult’s route and local signs.

Nature Field Guide

Rough-clawed Rock Crab

Spanish name: Cangrejo de roca de pinzas rugosas
Scientific name: Eriphia squamata

Coastal Life · Crabs & Hermit Crabs · Marine Life Rocky Shore

What Do Pico & Tati Think?

Pico notices the claws first. Tati checks the rest of the body before deciding what to write in the journal.

Identification

Key Features of the Rough-clawed Rock Crab

A broad carapace
Bumpy or rough-looking claw surfaces
Several features must agree for a confident identification

Habitat & range

Rocky shore and naturally visible tidal habitat. Choose a permitted observation point with an adult; do not turn rocks or reach into holes.

Conservation & care

Give claws and burrow entrances space. Do not handle, feed, chase or collect crabs. Leave rocks and shells where they are, and follow your adult’s route and local signs.

Nature Field Guide

Sally Lightfoot Crab

Spanish name: Cangrejo zayapa
Scientific name: Grapsus grapsus

Coastal Life · Crabs & Hermit Crabs · Marine Life Rocky Shore

What Do Pico & Tati Think?

A shore crab’s careful steps can make a rocky coast feel like a busy neighborhood. Pico and Tati watch from stable ground.

Identification

Key Features of the Sally Lightfoot Crab

A crab on coastal rocks
A broad low body with legs extending sideways
Compare color, outline and other details together

Habitat & range

Rocky shore and naturally visible tidal habitat. Choose a permitted observation point with an adult; do not turn rocks or reach into holes.

Conservation & care

Give claws and burrow entrances space. Do not handle, feed, chase or collect crabs. Leave rocks and shells where they are, and follow your adult’s route and local signs.