GECARCOIDEA CARE GUIDE
Author: Albomita
Gecarcoidea is a genus of large, powerful terrestrial crabs originating from Southeast Asia and Oceania. Although often labelled as freshwater crabs, they are better described as terrestrial crabs with a need for freshwater access. These crabs are becoming increasingly common in the exotic pet trade, but all specimens available as of now are wild-caught, which comes with both benefits and challenges in terms of hardiness, behaviour, and ethical considerations.
Their popularity stems from their impressive size, strength, and hardy nature, but with that comes a responsibility to provide the right care. This is not a beginner-level pet in aesthetic setups. While they are stunning and fascinating animals, their aggressive digging and sheer strength can make them a difficult species to keep in traditional decorative or plant-heavy enclosures.
Common Names
Gecarcoidea is also commonly known as:
Purple land crab
Members of the species
How to Tell the Difference between Gecarcoidea Humei and Gecarcoidea Lalandii
Left: G. Humei with very brightly colored orbital rims.
Right: G. Lalandii with dark orbital rim.
While Humei's eye sockets are painted in very bright colours, including white,
Lalandii’s eye sockets are perfectly blended with the colours of its carapace and underside.
(Gecarcoidea Lalandii):
Does it look like there is yellow/orange on the sides or carapace? → Lalandii
Are there orange or yellow triangular points right under the eyes (around the border)? → Lalandii
Does the carapace pattern look naturally blended with the carapace colour? → Lalandii
Does the eye area (orbital area) also appear to blend in with the colour of the carapace? → Lalandii
Gecarcoidea Humei):
Does the body (sides or carapace) appear brown/red? → Humei
Is the colour border just vague without a clear point right under the eyes (around the border)? → Humei
Does the carapace pattern (three white lines) stand out or feel intrusive? → Humei
Does it look like there is a white border around the eye (orbital area)? → Humei
Conservation level
Not officially evaluated. Due to their wild-caught status, habitat preservation and ethical sourcing are important considerations for responsible keepers.
Care level
Dark Method: Beginner, Suitable for those who follow the "dark method" of keeping crabs.
Love method: Advanced. Proceed with extreme caution and be prepared to move to a dark method.
The Dark vs Love Methods Explained
Enclosure and Environment
This species cannot be kept in a standard paludarium. They will rip up all your plants and destroy the tank. Give them a large, heavy water bowl that they cannot flip, as they are extremely strong creatures.
Temperature: 27°C / 80°F
Humidity: 80%
Minimum Tank Size: 45x45x45cm | 18x18x18”
Lighting: Provide a natural day-night cycle.
Substrate
Normal organic potting soil works for a love method, and crushed coral or medium gravel is best for a dark method.
Cohabitation
Avoid cohabitation. It is entirely luck-based and will only work based on the personality of your crabs. There doesn’t seem to be a rhyme or reason, they will just occasionally bond.
Diet
Feed a balanced diet of vegetables, fish pellets, and shrimp. Sodium-rich foods are very important, such as seafood and celery. Once a week, roll a shrimp around in sea salt in order to supplement the crab with salt.
Data Source
The information in this guide was kindly researched and provided by the team at Crustacean Council.