Quick Answer: Omothymus violaceopes, the Singapore Blue, is a massive Old World arboreal from Malaysia and Singapore reaching 9+ inches legspan. It needs a tall arboreal enclosure (18"+ height for adults), 78-86°F, and 70-80% RH. Old World venom — medically significant. Advanced keepers only. Download the free care sheet PDF.
Introduction
Omothymus violaceopes, commonly known as the Singapore Blue, is one of the largest tarantulas in the world and one of the most visually arresting. Adult females regularly exceed 9 inches legspan. Males are significantly smaller but compensate with intense iridescent blue coloration across the legs that has no equal in the hobby. The species ranges across Malaysia, Singapore, Sumatra, and Borneo, occupying tropical rainforest canopy and forest edge habitat where humidity stays consistently high.
This is an Old World species in every sense of the description: no urticating hairs, very fast, immediately defensive, and carrying venom that requires medical attention if a bite occurs. Experienced keepers who want a flagship display animal that earns genuine respect from every visitor to the collection will find nothing else quite like a fully grown Singapore Blue settled into a large arboreal enclosure.
This guide covers everything needed to set up and maintain Omothymus violaceopes correctly from sling to adult.
Quick Stats
| Parameter | Detail |
|---|---|
| Scientific name | Omothymus violaceopes |
| Common name | Singapore Blue |
| Origin | Malaysia, Singapore, Sumatra, Borneo |
| Habitat | Arboreal; tropical rainforest canopy and forest edge |
| Adult female legspan | 9+ inches (23 cm) |
| Adult male legspan | 5-6 inches; notable iridescent blue coloration |
| Female lifespan | 12-20 years |
| Male lifespan | 2-3 years post-maturity |
| Experience level | Advanced |
| Urticating hairs | None (Old World species) |
| Venom | Old World — medically significant; seek medical care after any bite |
| Webbing | Heavy; constructs extensive tube retreat |
Enclosure Setup
Height is the priority for Singapore Blues. Adults need a minimum of 18 inches of vertical space; 24 inches is better. A standard front-opening arboreal enclosure from any reputable keeper supply company works well, but a top-opening setup reduces escape risk during maintenance with a species this fast. Cross-ventilation is critical at this humidity level to prevent stagnant air and mold.
| Life Stage | Enclosure Size | Notes |
|---|---|---|
| Sling (under 1") | 6-16 oz deli cup | Side ventilation; anchor cork bark vertically |
| Juvenile (1-3") | 6"W x 6"D x 10"H | Arboreal; top-opening preferred |
| Sub-adult / Adult | 12"W x 12"D x 18"H minimum | Taller is better; 24"+ height recommended for adults |
Substrate: 3-4 inches of coconut fibre or a coconut/peat mix, kept lightly moist in the lower half. Anchor a large piece of cork bark vertically against the back wall — this becomes the primary tube web anchor. Singapore Blues are heavy webbers and will cover the inside of an enclosure with silk within weeks of being settled. A permanent water dish at substrate level is required.
Temperature and Humidity
This species originates from tropical lowland rainforest where temperatures are warm and humidity is consistently high year-round. Recreating this is straightforward with a heat mat on the side of the enclosure (never the bottom) and regular water dish maintenance.
| Parameter | Target Range | Avoid |
|---|---|---|
| Daytime temperature | 78-86°F (25-30°C) | Below 70°F or above 90°F |
| Night temperature | 72-80°F (22-27°C) | Sustained below 68°F |
| Ambient humidity | 70-80% RH | Below 60% or sustained above 85% |
| Substrate moisture | Moist lower half; dry surface | Completely dry or waterlogged throughout |
Overflow the water dish once a week to wet the lower substrate. Cross-ventilation is essential at this humidity level — good airflow prevents the bacterial and mold issues that stagnant humid enclosures develop. Do not allow the enclosure to dry out completely between maintenance sessions.
Feeding
Singapore Blues are strong feeders when established and comfortable in their enclosure. They ambush prey from the tube opening rather than actively hunting. Pre-kill prey for slings and small juveniles — live prey in an enclosed space with a freshly molted or small spider is an unnecessary risk with a species this size.
| Life Stage | Prey Item | Frequency |
|---|---|---|
| Sling | Fruit flies, pinhead crickets (pre-killed) | Every 4-5 days |
| Juvenile | Small crickets, small dubia roaches | Every 5-7 days |
| Sub-adult / Adult | Large crickets, large dubia roaches, superworms | Every 10-14 days |
| Pre/Post-molt | None — remove all live prey | Resume 14-21 days post-molt (adults) |
Remove uneaten prey within 24 hours. Pre-molt fasting can last 2-3 months in sub-adult and adult Singapore Blues — this is normal. Do not attempt to force-feed a fasting spider.
Watering
A permanent shallow water dish at substrate level is required. Overflow it once a week to moisten the lower substrate layer. Change the water every 3-4 days to prevent bacterial growth. For slings and small juveniles, moisten one side of the substrate by overflowing a bottle cap — no water dish needed at that size. Do not mist directly onto the spider.
Molting
Pre-molt signs in Singapore Blues: prey refusal lasting weeks to months (adults may fast 2-3 months before a molt), significant darkening of the abdomen, and heavy webbing or complete sealing of the tube entrance. Do not disturb a spider in pre-molt or during an active molt. Remove all live prey immediately.
Post-molt hardening takes longer in this species than in smaller tarantulas. Wait a minimum of 14 days for juveniles and 21 days for sub-adults and adults before offering food again. Fangs must be completely dark before feeding resumes. Offering prey before the spider has hardened fully risks injury to both the spider and the keeper.
Temperament and Handling
Do not handle this species. The Singapore Blue is one of the fastest tarantulas in the hobby and bites as a primary defense mechanism — it does not bluff-posture or give extended warning signals before striking. Old World venom is medically significant; a bite from an adult warrants immediate medical evaluation.
Use a large clear acrylic container and long metal tongs for all enclosure maintenance. Work slowly and deliberately. Always confirm the spider's location before opening the enclosure. This species can cross a large enclosure in under a second. Never reach bare-handed into the enclosure for any reason.
Is This Species Right for You?
If you are keeping your first tarantula, or your first Old World species, the Singapore Blue is not the right choice. This is a species for keepers who have already worked with fast, defensive Old World arboreals and understand the difference between a measured threat posture and a species that bites without warning.
If you are an experienced keeper looking for a long-term display animal with no equal in the hobby for sheer visual impact, and you have the right equipment and a clear-headed approach to working with a medically significant species, the Singapore Blue is exactly that. Females live 12-20 years. A well-settled adult in a large arboreal enclosure with a fully developed silk retreat is one of the most impressive animals you can keep.