GEOSESARMA PONTIANAK (MANDARIN VAMPIRE CRAB)
Geosesarma Pontianak @milleniumsnakes
Scientific Classification
Scientifically Described: Yes
Availability in trade: Yes
Discoverer: Ng, Peter K. L. (2015)
Other common names: Mandarin, Geosesarma Notophorum
Activity: Mostly Crepuscular, Nocturnal
Difficulty Level: Master
Identification & Characteristics
Geosesarma Pontianak is a small, semi-terrestrial crab species with distinct white claws, commonly referred to as the Mandarin Vampire Crab. This species is often confused with Geosesarma Notophorum (White Mandarin Vampire Crab), making identification and proper labelling a little tricky. Especially when you are searching for images, as they are always mixed up.
APPEARANCE
Carapace: Subtle blue/grey on the back and mostly red on the underside.
Legs: Bright red legs
Claws: Bright orange
Eyes: Light green or yellowish. Usually not as bright yellow as other Vampire Crab species.
Underside: Reddish brown.
Size: 2-2.5 inches across, slightly bigger than the average vampire crab.
Activity: Mostly crepuscular and nocturnal, though they are observed to be more active during the day compared to other species.
Aggression: Aggressive, particularly among males. They require at least twice the space of other species to minimise male fighting. An 80x30x30 cm enclosure or larger is recommended. Use a vertical-style enclosure for maximum comfort. If they don’t have enough space, they will fight and kill each other.
Interesting Fact: Large female Geosesarma Pontianak are sometimes indistinguishable from the males. Their claws are almost identical in size, so sexing them has to be done from their underside.
Distribution & Habitat
Geosesarma Pontianak come from North Pontianak – West Borneo, Indonesia
Habitat Preferences: Unlike many other Geosesarma species, Mandarins don’t use the water all that much, though it is still required in their environment. They molt on land and prefer to spend time in the canopy, making them perfect for taller enclosures. Provided them with a standard water section and some small water pools higher up in their tank to keep their gills moist.
A large vertical-style enclosure like this Exo-Terra 45×45×90cm is best.
Diet
Mandarin Vampire Crabs are omnivores and accept a wide range of foods.
Food Preferences: While they consume most commercial fish foods, they particularly enjoy hunting live foods such as isopods, crickets, springtails, fruit flies, and worms. The more dietary choices you give them, the better, especially small live insects they can hunt and eat.
Behaviour & Social Dynamics
Males: Highly aggressive, especially in confined spaces, which increases the likelihood of fights. Providing a larger enclosure is the only way to minimise conflicts. Quite often, fights will end in death if they don’t have enough space to escape battle.
Females: Less is documented about female behaviour, but like males, they likely benefit from spacious environments to reduce stress.
geosesarma Pontianak Molt on Land
Unlike most other Geosesarma species, Geosesarma Pontianak generally molts on land and not in the water, but there are observed instances where they have been known to molt in water or right on the edge of a water source.
GEOSESARMA Pontianak BREEDING
Whilst their molting processes are different, their breeding process is quite similar to all other Geosesarma species. However, females don’t spend as much time hiding in burrows in the soil. Female Geosesarma Pontianak are quite often indistinguishable from males once they reach full size. Their claws are almost identical in size, so sexing them has to be done from their underside.
Female Geosesarma Pontianak also don’t carry their babies on their underside instead, they are carried on their backs in a similar way that some species of spiders and scorpions do. A rough estimate from mating to babies becoming free-roaming is around 95-100 days. Give or take a week.
Challenges in Captivity
If you’re planning on keeping Vampire Crabs, you’ll need to read this care guide. It covers the general requirements and rules for all Geosesarma species. However, for Geosesarma Pontianak, it’s best to get a large vertical tank to keep them in.
Fragility: Geosesarma Pontianak is considered one of the most delicate species within the hobby. They suffer from a very high mortality rate during shipping, with up to 95% dying within the first 4-6 weeks after shipping. Due to their poor survival rate, this species is not recommended for novice keepers.
Important: If you're new to vampire crabs, it’s best to avoid Geosesarma Pontianak as your first choice.
ENVIRONMENTAL PARAMETERS
Air Temperature: 22–28°C (71–82°F)
Overnight lows and daily highs are normal, so if your tank goes from 20–30c over a 24-hour period (slowly) that is perfectly fine. This is very similar to what happens in nature. Though you will need a heater for your tank during the colder months of the year.
WATER SECTION RULES:
While they don’t use the water all that often, if at all, the below are the required parameters all other Geosesarma species require. Which is also suitable for Geosesarma Pontianak.
Water temperature: 22–25°C (71–78°F)
PH: Between 7.5–8.0
KH (carbonate hardness): Between 0–10
GH (general hardness) Between 4–16
Ammonia: 0
Nitrite: 0
Nitrate: Lower than 20 ppm
There’s a lot more to keeping Geosesarma species, so make sure you read this guide as well if you are planning to keep them.
Tank Design is Really Important
Include Bromeliads: These crabs love to utilise the small water reservoirs that naturally form in bromeliads. It's a great way to provide extra hydration opportunities and create a more enriching environment.
Provide Multiple Water Sources: Adding a second small water dish on the opposite side of the tank ensures they don’t have to congregate in one place to drink. This helps reduce tension and makes hydration more accessible.
Minimise Aggression Through Layout: To prevent fights, avoid creating areas where they’re likely to cluster. Spread out hides, water sources, and climbing areas to keep them moving and separate.
Feed in Multiple Locations: When feeding, distribute food in several areas of the tank. This minimises competition and aggression during feeding time, giving all individuals a fair chance to eat.
Conservation Status
There is limited information on the conservation status of Geosesarma Pontianak, but like many other species in the hobby, habitat loss and over-collection may be potential concerns.