Pagurus middendorffii is a small cold-water hermit crab of the western North Pacific with long, smooth claws and legs. It lives on rocky shores in the Russian Far East, northern Japan, and eastern Korea, and there are no well-documented records from US shores. Scientists in Japan have studied how males guard females before mating and fight rivals with their big right claw.
Appearance
- Appearance
- The carapace and legs are smooth, without hairs or spines, and the claws and walking legs are notably long.
Where it lives
- Typical habitats
- Rocky shores
- Intertidal zone
- Range
- Coastal waters of the western North Pacific, from the Russian Far East to northern Japan and the east coast of Korea. Some references extend its range to the North American side of the Pacific, but well-documented US records are lacking.
- Preferred conditions
- A cold-water species of the intertidal zone that lives in empty snail shells.
Behavior
- Social life
- Before mating, a male stays with a female and guards her for a while. When a rival approaches, the guarding male thrusts his big claw forward to fend him off; if the fight escalates, the bigger male with the longer claw usually wins.
Life cycle
- Breeding season
- In Japanese studies, the mating season is around November.
- Reproduction
- A male that loses its big claw regrows it at the next molt, though the new claw is more slender.
Conservation
- IUCN Red List
- NENot EvaluatedNot yet assessed
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