Chilobrachys natanicharum (Electric Blue Earth Tiger) 0.75" | 5" FEMALES

For this spider, the party's all upfront- and it’s a party you do not want to miss. Despite being in the hobby for several years as Chilobrachys sp. “Electric Blue,” Chilobrachys natanicharum (Chomphuphuang et al.) was only described formally in 2023 and is a wildly beautiful, absolute unit of a tarantula. These flashy members of the subfamily Selenocosmiinae were scientifically described as sporting a “blue-violet hue resembling the color of electrical sparks.” They reside within 5 meters of sea level in tree hollows of steamy coastal mangrove forests of southwestern Thailand.

C. natanicharum is found within 5 meters of sea level in mangrove forests. They colonize mangrove tree hollows. Spiderlings and juveniles typically construct funnel sheet webs in hollows. Adults web up interiors of tree hollows as well, waiting at the mouth of tree cavities for passing prey at night. While spiderlings begin life resembling many other members of Selenocosmiinae, mostly dark in coloration, their transformation into a technicolor beast becomes more apparent with each molt. Over time, the abdomen and two posterior (hind) pairs of legs remain a drab mousy gray in coloration as the carapace takes on champagne to silver tones. However, the chelicerae and interior surfaces of the anterior (front-facing) two pairs of legs progressively become more metallic silver, purple, royal blue and electric sky blue with each molt toward adulthood. If you view them with a headlamp, you will notice how the metallic colors drastically change with every slight shift in angle of every leg or chelicerae segment as they race through their elaborate silk-lined tunnels.

Chilobrachys are tough and hardy Old World tarantulas with a rapid growth pace and one gluttonous appetite. They probably would try to take down a moose if you let them- so don’t!  While not quite that ambitious, C. natanicharum has no qualms tackling prey their size or larger. Be warned: these tarantulas sometimes even impale their prey like purseweb spiders by puncturing straight through the silk walls or floors of their tunnels with their hefty chelicerae. Watching these tarantulas in action is probably not far from a low budget horror film playing somewhere on mute in the middle of a rave or goth club.

As a member of Selenocosmiinae, C. natanicharum is equipped with long spinnerets, and webs copiously throughout any open space in its enclosure. Being facultative arboreals in nature, a vertical setup with cross ventilation, plenty of substrate, Magnolia leaves, cork bark, etc. works well for C. natanicharum. These spiders can attain an impressive leg span of 7 inches (~17cm) and despite being leggy, mature females become surprisingly robust.

Maintain a humid enclosure with somewhat moist substrate for spiderlings through adulthood. This and other Chilobrachys species are tough tarantulas and tolerate drier substrates as they attain size. However, it is good practice to ensure at least one side or corner of the enclosure is periodically misted to provide some soil moisture and humidity. Typically, if part of the substrate on a side of the cage is kept moist (not wet) from occasional targeted mistings, the spider should be alright and locate its ambient zone somewhere along the moisture gradient in its enclosure. A water dish is also beneficial for larger specimens.

Similarly to other genera within Selenocosmiinae, C. natanicharum is an elegant, leggy tarantula with a bullet-shaped carapace and elongate abdomen, making them lightning fast and agile. Since members of this tarantula subfamily have rather strong venom and C. natanicharum are highly defensive with a bold feeding response, these spiders should not be handled and care must be taken to locate the spider’s position before opening the enclosure. It is not uncommon for C. natanicharum to rush toward your hand as you open the enclosure, so watch your fingers when working with their enclosures. Best enjoyed like insanely cool tropical fish with fangs. If you are a color junkie that likes Old World tarantulas, you will not regret getting this ridiculously beautiful species.

Husbandry Recommendations - 4" MALE/FEMALE

This is a fossorial spider, so it will require an enclosure which offers more vertical space than floor space. The rule-of-thumb for the height of the enclosure is 3-4x leg span minimum. We recommend this spider be housed in the Spider Haus 'Haplotank'. They will need room to burrow and cross ventilation is not necessary. Fossorial spiders will burrow, and need more depth of substrate. So, fill up the enclosure 2/3 - 3/4 full. Our choice of substrate is a unique blend of coco and other organic materials - Hunter's Premium Substrate. This substrate will retain humidity, allow for sturdy burrows, and resist mold or fungal growth. Offering a cork bark flat can offer cover for the spider until it begins to burrow. Finalize the enclosure by adding Sphagnum Moss, Mixed Leaf Litter, or Magnolia Leaves for aesthetic. Some fossorial spiders build intricate turrets. They will use the organic material available to them to do so. 

We anticipate a necessary level of moisture in the substrate for this species. Soak the substrate from the bottom-up by putting the haplotank in standing water. Water will wick up into the substrate from the bottom ventilation, offering the spider a natural bottom-up moisture gradient. Allowing excess water to drain will complete the process. The substrate should never be fully dried out. From others experience, this soaking is only required twice per year. 

Common tools which would be helpful in caring for this spider include tweezers. These are used for feeding, cleaning, and rearranging the enclosure if needed. Another useful tool is a Mister. This allows for controlled and purposeful watering. 

Our suggestion for feeders is large crickets. Other large insect feeders also work - red runners, dubia roach, mealworms (smash the heads first).