The Thukuhar Shore-crab, Alamihi Crab, Mangrove Crab, Mangrove Rock Crab – Metopograpsus thukuhar is a fascinating crustacean found in coastal waters around the world. This crab is known for its adaptability to a variety of habitats, including brackish water, tidal zones, and mangrove zones. Its unique characteristics and behaviors make it an important part of the marine ecosystem.
Description & Characteristics
Metopograpsus thukuhar is a medium-sized crab, with individuals reaching a maximum size of approximately 5-8 cm in carapace width. It exhibits a distinctive carapace, often featuring a mottled brown or gray coloration with a smooth, slightly convex surface. The crab possesses five pairs of walking legs, with the front pair modified into large, powerful claws. These claws are used for defense and for capturing prey.
Habitat and Occurrence
Metopograpsus thukuhar is a highly adaptable species, found in a variety of coastal habitats. It is particularly common in the supralitoral zone, which is the region above the high tide line. This zone is characterized by its exposure to air and freshwater runoff, making it a challenging environment for many marine organisms. However, Metopograpsus thukuhar thrives in these conditions, often seeking refuge under rocks, logs, or in crevices.
The crab’s preference for unconsolidated muddy grounds in the intertidal zone is also well-documented. This provides access to abundant food sources and shelters from predators. This adaptable crab also frequents mangrove zones, which offer a complex network of roots and vegetation, providing ideal conditions for shelter and breeding.
Taxonomy
The species Metopograpsus thukuhar belongs to the Class: Malacostraca, Order: Decapoda, and Family: Grapsidae. This classification places it among the diverse group of crabs that are characterized by their broad, flattened carapaces and generally adapted for life in coastal habitats.
Feeding
Metopograpsus thukuhar is an omnivore, exhibiting a diverse diet that includes both plant and animal matter. This makes it a highly adaptable feeder, capable of taking advantage of available food sources in its environment. It has been observed feeding on algae, carrion, and even smaller crabs, displaying a predatory nature. This opportunistic feeding strategy allows it to thrive in various ecological niches, contributing to the overall balance of its ecosystem.
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