Species information
Scientific name: Tuerkayana hirtipes
Japanese name: オカガニ
Chinese name: 毛足特氏蟹
English name: Pacific land crab
Origin: Widely distributed from the tropical Indian to Pacific regions
Ecology and description
Narrowly defined land crabs refer to crabs of the family Gecarcinidae. There are 6 species of land crabs in the Ryukyu Islands:
- Tuerkayana hirtipes (Pacific land crab)
- Cardisoma carnifex (Brown land crab)
- Tuerkayana rotunda
- Gecarcoidea lalandii
- Epigrapsus notatus
- Epigrapsus politus
The Pacific land crab has a carapace that is dark in color, ranging from dark brown to black, with black eyes and a quadrilateral area of short hairs on the cheeks. It mainly inhabits areas behind coastal forests where freshwater is found at the bottom of burrows. During the summer high tides, this species frequently goes to the seaside to spawn. However, due to current coastal environmental destruction and roads being built along the coast, the Pacific land crab often falls victim to roadkill, leading to a rapid decline in its numbers.
References:
Armor of the Coastline (Chinese Website)
Distribution of Land Crabs Around Japan (Japanese Website)
Distribution of 6 species of land crabs in Japan (Reference Material)
Field photographs taken during our tours, with observation dates
On the nights of summer high tides, there is a chance to see this species releasing juveniles at the coast. We hope vehicles will drive cautiously and slowly to avoid roadkill.
