Mud crab

Amazing fact

When moulting, the mud crab expands its new shell with water.

Queensland Government

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An illustration based on the real animal.

A little discovery to share.

When moulting, the mud crab expands its new shell with water.

SourceQueensland Government — Mud crab aquaculture

THE REAL WORLD

The real Mud crab

Scientific name: Scylla serrata
Japanese name: アミメノコギリガザミ
Group: Freshwater animals

Class: Malacostraca
Order: Decapoda
Family: Portunidae
Genus: Scylla

Facts about the real animal.

Where the name “Mud crab” comes from

The dark net-like pattern on its claws and walking legs gives it the Japanese name part “amime”.

天城町歴史文化産業科学資料センター・ユイの館

It lives in river mouths and mangrove swamps in the Ryukyu Islands, Southeast Asia, Australia and India.

鳥羽水族館 — アミメノコギリガザミ

At low tide, it hides in a burrow in the sand or mud.

鳥羽水族館 — アミメノコギリガザミ

At high tide and at night, it is very active.

鳥羽水族館 — アミメノコギリガザミ

How the Mud crab lives

It cracks open shellfish to eat and moves quickly to catch fish, shrimp and crabs. It also eats fallen leaves and nori-like algae growing on rocks. When danger approaches, it rows with its paddle-like legs to swim quickly. During breeding, a male holds a female in a burrow and waits for her to moult.

天城町歴史文化産業科学資料センター・ユイの館

Basic data

Active: At night (nocturnal)
Range: Ryukyu Islands, Southeast Asia, Australia, and India

鳥羽水族館

Where the Mud crab has been recorded

Records: GBIF.org (CC0 and CC BY 4.0 records, retrieved 2026-11-07). Map: Natural EarthSee the records on GBIF

Where it livesJapan Asia Australia Coasts Rivers and wetlands

Watch wild animals from a distance. Do not touch or feed them, and take care of the places where they live.

Names around the world

日本語: アミメノコギリガザミ
简体中文: 锯缘青蟹
繁體中文: 花蟳
한국어: 남방톱날꽃게
Español: Cangrejo de manglares
Français: Crabe des palétuviers
Português (Brasil): Caranguejo-de-manguezal
Italiano: Granchio delle mangrovie
العربية: سلطعون أسود
Bahasa Indonesia: Kepiting bakau besar
ไทย: ปูเขียว

Names come from Wikidata and iNaturalist records. Where a language has no recorded name, we use the scientific name.

Sources and how we check

鳥羽水族館 — アミメノコギリガザミChecked: 2026-11-04
天城町歴史文化産業科学資料センター・ユイの館 — アミメノコギリガザミ ( Mud crab )Checked: 2026-11-07
Queensland Government — Mud crab aquacultureChecked: 2026-11-07

We check each fact against its source. The illustrations simplify how the real animal looks.

The classification (class, order, family, genus) follows Wikidata records, checked against GBIF. Classifications can change as research goes on.

The basic data are the values given in each source. They vary with how the animal is measured, whether it is male or female, and whether it lives in the wild or in captivity.

This page was translated from the original Japanese with the help of AI.

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