Parathelphusidae

Taxonomically, they belong to the order Decapoda. Their ability to survive in various aquatic habitats allows them to establish stable populations within irrigation canals and paddy fields. They are opportunistic feeders, shifting their diet towards tender vegetation when rice seedlings become available.

The primary damage caused by these crabs includes cutting off young rice stems near the base, leading to significant thinning of the crop stand. Additionally, their burrowing behavior destabilizes the earth embankments of paddies, resulting in water loss and irrigation inefficiency, which is critical for rice management.

Their life cycle is synchronized with the hydrological regime of the rice fields. Breeding is generally triggered by the onset of monsoon rains. Adults spend their days in deep burrows to avoid heat and predation, emerging at night to forage, which makes the implementation of control measures particularly challenging.

Effective management strategies require a multifaceted approach:

• Strategic draining of fields during the critical seedling stage to disrupt the crab's habitat.
• Installation of wire mesh or fencing to prevent crab migration into sensitive plots.
• Use of botanical extracts or localized chemical treatments where severe outbreaks occur.
• Maintaining well-structured dikes to reduce the number of suitable burrowing sites.