Phormingochilus arboricola

Phormingochilus arboricola hails from the lush, dense rainforests of Borneo, that magical island paradise in Southeast Asia. Life here is all about towering trees, thick canopies and humid air – perfect for a spider with a fondness for the high life. In the wild, these tarantulas are perfectly at home nestled within tree hollows, bark crevices, or hiding in leaf litter high above the ground. Temperatures are consistently warm and the air is pleasantly muggy – just what you'd expect from a tropical haven.

A fully grown P. arboricola generally reaches 13–15 cm in diagonal leg span. Females tend to be a bit more substantial than their male counterparts, both in bulk and in lifespan. Males are leggier and look rather like spidery teenagers compared to the chunky girls. Growth is reasonably quick, so juveniles can surprise you by filling out their arboreal digs in just a year or two with good food and above average parenting from their keeper.

Strictly an arboreal customer, Phormingochilus arboricola spends its time off the ground, embracing all things vertical. In captivity, it tends to build silken retreats up high, wedged behind bark or in cork tubes, and rarely heads earthwards unless there’s a good reason (like a poorly placed dinner cricket). They're agile climbers, quietly prowling their silk canopy and decorating their home with impressive webs.

Females are pretty long-lived, often making it to the ripe old age of 12–15 years in captivity if properly cared for. Males, rather like mayflies on a fast track, generally top out at around 3–5 years and their days are especially numbered once they become mature. Good husbandry, low stress, and a hands-off approach help everyone live their best (eight-legged) life.

P. arboricola is a moderately fast grower. Slings put on leg length surprisingly quickly, especially if you keep them well-fed and toasty. That said, temperature, food quality, and a stress-free environment can all play a part. They’ll shed regularly as youngsters, so keep an eye out for moults and be prepared for a sudden growth spurt here and there.

Not for the reckless or easily surprised! P. arboricola is skittish and lightning-fast – think ninja in a silk dressing gown. They tend to bolt rather than bite, but if properly provoked or cornered, they won’t hesitate to display a threat pose. This species is best enjoyed with a healthy respect (and a closed enclosure). As you’d expect with an arboreal, their vertical escapes can defy even the most well-meaning tongs, so have a catch cup handy on maintenance days.

This species prefers temperatures of 22–26°C during the day, with a gentle drop at night (no fridge-like chills required, mind you). Anything a bit above UK room temperature is about right, though avoid anything too hot or too cold. If your house hovers in the 18–20°C range, an oil-filled radiator or heat mat (with a thermostat) near the enclosure side is your safest bet – just never put a heat mat underneath! Keep a thermometer inside to avoid wild weather happening in the spider’s personal penthouse.

P. arboricola loves a humid environment: aim for 70–80% relative humidity. Achieve this with lightly moist substrate (not sodden!) and regular gentle misting, being sure never to drown their silken creations. Good cross-ventilation is vital so mould doesn’t join your collection. Always provide a clean, shallow water dish, and make humidity adjustments based on moult cycle and seasonal changes – you’re not running a swamp, but you are aiming for rainforest vibes.

This is a classic 'see you sometimes' species. You’ll spot your P. arboricola most often at night, especially if you keep the room dim or use red light. During the day, expect to see fabulously webbed hideouts and the occasional pair of knees or toes sticking out. They’re not always out and about, but their impressive webwork and occasional display make ownership a visual treat for patient keepers.

Web architects extraordinaire! P. arboricola crafts thick, messy silken tunnels tucked into bark, cork or within artificial foliage. Their webbing often covers most of the vertical surfaces and hides. It’s fascinating to watch them work, and the web complexes provide privacy and protection – almost like a penthouse suite behind silk curtains. Webbing is a key indicator of their happiness – the more web, the more comfy your tarantula feels.

Food-wise, P. arboricola isn’t a fussy eater. Juveniles and adults will readily take down crickets, locusts, dubia roaches, and the occasional waxworm for a treat. Slings should be offered chopped mealworms or pre-killed baby crickets every 4–5 days. Juveniles do well on 1–2 appropriately sized insects a week, while adults usually take a large cricket or similar prey every 7–10 days. Their feeding response is fast and dramatic – picture a tiny ninja leaping from a web fortress. Keepers should avoid overfeeding (don’t create a furry beach ball on legs), especially with slower-growing females. Always remove uneaten prey after 24 hours, especially before moults, and never feed directly after a moult. Hydration is important; don’t substitute juicy prey for a proper water dish.

An arboreal set-up is essential. For slings and juveniles, a tall, well-ventilated container with good cross-ventilation is ideal. Adults need a terrarium of at least 30cm tall, with vertical surfaces for climbing – cork bark tubes, upright wood, and plenty of anchor points for webbing. Floor space is less critical than height, but a 20x20x30cm enclosure is a good start. Substrate (coco fibre or a mix) should be 5–8cm deep and kept just lightly moist. A water dish is non-negotiable for all life stages. Ventilation is key to prevent mould, especially with higher humidity. Artificial or live plants (safe for tarantulas) make webbuilding more interesting and natural. Avoid old-school mesh lids to prevent injury – small vents or secure holes in acrylic are best. Above all, make maintenance easy and escapes difficult!

Not quite a spiderling’s first tarantula, but a real treat for keepers with some experience under their belt. Their skittish nature, speed, and humidity needs make them better for intermediates or folks who’ve already wrangled a few more forgiving species. Not recommended for beginners or the faint-hearted, but absolutely rewarding for those ready to level up their arboreal game.

Phormingochilus arboricola is one of the hobby’s unsung gems – striking, active, and a fantastic webber for anyone willing to keep up with its speed and fussiness about humidity. They won’t tolerate neglect or clumsy hands, but treat them to a lush, well-ventilated vertical palace, and you’ll be rewarded with a spider that’s both stunning and full of character. They won’t win any awards for sociability, but their antics and webbing prowess make them a favourite among arboreal lovers. If you’re ready for the challenge and keen on a tarantula that turns coconut fibre into high-rise silk, this is one species that will keep you interested and on your toes.