Red Devil Crab Care Guide
Geosesarma hagen · Freshwater Invert
What Red Devil Crab look like
The Red Devil Crab (Geosesarma Hagen) exhibits a strikingly vivid red-orange exoskeleton, which can reach a maximum adult size of approximately 5 cm (2 inches) across the carapace. This semi-terrestrial crab displays sexual dimorphism, with males typically possessing larger and more pronounced claws compared to females, which are generally smaller and more slender. The carapace is laterally compressed, providing a streamlined shape that facilitates movement both in water and on land. Notable morphological features include a well-defined rostrum and a pair of robust chelae that are adapted for both foraging and defense. The species possesses a unique adaptation of a gill chamber that allows it to respire in both aquatic and terrestrial environments, and its bright coloration serves as a warning to potential predators, indicating its potential toxicity. Additionally, the presence of a distinct lateral line system aids in detecting vibrations in the water, enhancing its sensory perception.
Behavior & temperament
Geosesarma Hagen is primarily a semi-terrestrial crab that exhibits both solitary and social behaviors, often found in small groups near water sources. It is typically benthic, dwelling in the intertidal zones where it can easily access both land and water. The species is known for its territorial nature, particularly among males, which can lead to aggressive displays during mating season. Breeding behavior involves the female laying eggs in a moist environment, where they are cared for until they hatch into larvae. The Red Devil Crab is generally considered to have a moderate temperament, but can exhibit aggressive tendencies when provoked or during territorial disputes, particularly in confined spaces.
Diet & feeding
In the wild, the Red Devil Crab is an omnivore, feeding on detritus, algae, and small invertebrates. In captivity, it requires a varied diet that includes high-quality pellets, blanched vegetables, and occasional protein sources such as freeze-dried or live foods to ensure optimal health and coloration.
Behind the name
Geosesarma (earth crab); Hagen (named after the German zoologist Hermann Hagen).
Plan your tank
Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.
Keeping Red Devil Crab?
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