Ocypodidae
Ocypodidae is a family of crabs in the infraorder Brachyura. It is a diverse family with over 100 species, and are commonly known as ghost crabs, fiddler crabs, and sand crabs. They are found in a variety of habitats, from sandy beaches and mudflats to mangrove swamps and estuaries.
Characteristics
Ocypodidae crabs are characterized by their flattened bodies, long legs, and large, prominent eyes. They typically have a carapace that is wider than it is long, and their claws are often large and powerful. Their color can vary greatly, but they are often a pale, sandy color.
A key characteristic of fiddler crabs is their striking sexual dimorphism. Males have one enlarged claw (often brightly colored) that they use for attracting mates and fighting with rivals. They can also wave this large claw to communicate with other fiddler crabs. Females have two small claws.
Environments
Ocypodidae crabs are found in a variety of coastal habitats. They are particularly common in intertidal zones, where they are exposed to both air and water. They are also found in mangrove forests, estuaries, and salt marshes.
Ghost crabs, especially, are known for their ability to burrow into the sand, where they can escape from predators and harsh environmental conditions. They often emerge at night to feed on decaying organic matter, small invertebrates, and seeds.
Behavior and Ecology
Ocypodidae crabs are active predators and scavengers, and their diet consists of a variety of organic material, including algae, diatoms, and detritus. They play a significant role in the food web by helping to recycle nutrients. Some species are known to be herbivorous, feeding on plants and grasses.
Several species of fiddler crabs display complex courtship rituals. Male fiddler crabs attract mates by waving their large claw, which produces a unique, species-specific vibration that can be detected by females. Some species of fiddler crabs are also known to communicate using visual signals, such as changing colors or waving their claws.
Examples of Ocypodidae crabs
Here are some common examples of Ocypodidae crabs:
- Ghost crabs (Genus Ocypode)
- Fiddler crabs (Genus Uca)
- Sand crabs (Genus Lepidopa)
References
For further information on Ocypodidae, please see the following webpages: