The Blue Gem: Care Guide for the Psednocnemis brachymarosa
Introduction
The Psednocnemis brachymarosa, commonly known as the Malaysian Blue Femur, is a highly prized and relatively uncommon species that captures the attention of the tarantula community. Hailing from the Malaysian peninsula, this beautiful tarantula offers a compelling colour transformation. While slings are a modest brownish colour, the adult form develops an incredibly appealing feature: an iridescent, striking blue sheen covering the entire body, making it a true jewel of the old-world genera. This vibrant, exotic look, combined with its burrowing nature, makes it a captivating, specialized acquisition for the experienced keeper.
Size, Growth, and Longevity
The Psednocnemis brachymarosa is considered a medium-sized species. Its adult leg span typically reaches around 4 inches, which, while not a giant, is a compact size that displays its vivid colours effectively. The growth rate for this species is generally moderate. The transformation from the drab brownish sling to the dazzling, iridescent blue adult is a major milestone that many keepers eagerly anticipate. Due to its smaller size compared to some larger species, the adult lifespan for females is respectable, often reaching 10 to 12 years, offering a good longevity for the dedicated keeper.
Temperament and Suitability for the Keeper
The Malaysian Blue Femur is definitively classified as an old-world species. This means it is fast, highly defensive, and possesses medically significant venom, relying on speed and striking rather than urticating hairs. Its natural behaviour is distinctly terrestrial/fossorial; it prefers to live within deep, intricate burrows and is rarely seen outside of its hiding place during the day.
Given its speed, potent defence, and tendency to bolt or threaten when disturbed, the Psednocnemis brachymarosa is strictly reserved for expert or advanced keepers. It is not a suitable species for beginners due to the necessary high temperatures and its unpredictable, defensive temperament. The keeper must be proficient in safely managing fast, burrowing old-world tarantulas to maintain this gorgeous creature responsibly.
Enclosure Setup
The primary requirement for this terrestrial/fossorial species is depth. The enclosure must be secure and allow for deep burrowing, with a substrate layer of at least 5 to 8 inches. The substrate should be packed and lightly moist to allow the tarantula to construct and maintain a stable tunnel system.
Crucially, the Psednocnemis brachymarosa requires higher ambient temperatures than many common tarantula species kept in the UK. The ideal thermal range is between 25C to 30C. This high-end temperature demand necessitates external heating equipment and precise monitoring by the keeper to ensure the survival and health of the species. Providing a starter burrow or cork bark to anchor the entrance is beneficial.
Conclusion
The Psednocnemis brachymarosa is a highly rewarding tarantula for the advanced keeper willing to meet its specific environmental demands. The combination of its stunning, iridescent blue colour, fascinating terrestrial/fossorial behaviour, and the challenge inherent in keeping a high-heat old-world species makes it a truly special addition to a mature collection. For those who can maintain the required high temperatures and respect its defensive nature, the Malaysian Blue Femur is a compact blue gem.
