Common name: Red-spotted Guard Crab

Care

The Red-spotted Guard Crab is relatively easy to care for, making it a great addition to reef aquariums. It thrives in tanks with plenty of live rock and branching corals, particularly Pocillopora species. These crabs are highly dependent on their host coral, so it is essential to provide a suitable coral species for them to establish their symbiotic relationship.

Stable water parameters and a well-maintained reef environment are crucial for the health of both the crab and its host coral. Regular monitoring of water quality and the coral's condition will ensure a harmonious and thriving setup.

Diet and Feeding

In the wild, Trapezia tigrina primarily feeds on the mucus and detritus produced by its host coral. In captivity, it will continue to rely on its host coral for sustenance but may also scavenge for other food particles in the tank. Supplementing its diet with fine particulate foods, such as plankton or coral-specific liquid foods, can help ensure its nutritional needs are met.

Feeding frequency is minimal, as the crab's primary source of nutrition comes from its host coral. However, occasional supplementation can be beneficial, especially in tanks with limited natural food sources.

Behavior and Compatibility

The Red-spotted Guard Crab is generally peaceful and spends most of its time within the branches of its host coral. It is highly territorial and will actively defend its coral from potential threats, including coral predators and other crabs. This protective behavior makes it a valuable addition to reef tanks with branching corals.

While Trapezia tigrina is compatible with most reef-safe fish and invertebrates, it may show aggression towards other crabs or similar species that encroach on its territory. It is best kept singly or as a mated pair within a tank to avoid conflicts.

Symbiosis

One of the most intriguing aspects of Trapezia tigrina is its mutualistic relationship with branching corals, particularly Pocillopora species. The crab defends its host coral from predators and pests, ensuring the coral's health and survival. In return, the coral provides the crab with shelter and a steady food supply. This symbiotic relationship is a prime example of mutualism in marine ecosystems and adds a dynamic layer of interaction to reef tanks.

Health and Common Issues

The Red-spotted Guard Crab is hardy when provided with a suitable coral host and stable water conditions. However, the health of the crab is closely tied to the health of its host coral. Stress, poor water quality, or coral decline can negatively impact the crab's well-being.

When selecting a Red-spotted Guard Crab, look for active individuals with vibrant coloration and no visible signs of damage or disease. Ensure that the host coral is healthy and free of pests or diseases before introducing the crab to the tank.

Routine maintenance, including regular water changes and monitoring of coral health, will help prevent common issues and ensure the long-term success of this symbiotic duo.

Habitat

In the wild, Trapezia tigrina is found in the Indo-Pacific region, inhabiting shallow reef environments with abundant branching corals. Its natural habitat includes lagoons and reef slopes, where it resides within the protective branches of its host coral. Replicating these conditions in a reef tank, with plenty of live rock and suitable coral species, will provide an ideal environment for this fascinating crab.