Megaphobema robustum

Megaphobema robustum is found in the humid, tropical forests of Colombia, with populations also scattered through neighbouring regions of Brazil and Ecuador. Their wild homes are the sort of lush, steamy rainforest environments that make your houseplants weep with envy – think dense leaf litter, tangled roots and high moisture. Temperatures are generally steady, thanks to the shielding rainforest canopy, rarely seeing extreme highs or lows. This species adapts to life both on and occasionally beneath the forest floor, making use of natural hollows, old burrows, and fallen logs for cover. All told, they're proper jungle dwellers that thrive in reliably warm, muggy surroundings.

Full-grown Megaphobema robustum are absolute chunky monkeys of the tarantula world, with adults reaching an impressive 16–18 cm diagonal leg span. Females are built like tanks—broad, heavy, and robust (fitting, given the name), while males look leggier, a touch more streamlined, and always a bit on the run once mature. Don’t be shocked by their girth—their size is definitely part of their charm! Growth is rather steady and, like a fine cheddar, it takes time for these beauties to reach their full glory, especially females.

Megaphobema robustum is a terrestrial species with fossorial tendencies. This means they love to turtle their way about, mostly hugging the ground but often disappearing into self-made burrows or hidey-holes when they feel the urge. In the hobby, they’re fond of rearranging substrate and using any décor you thoughtfully provide to make a snug retreat. While you may occasionally spot them out and about exploring (especially after dark), most mature specimens settle in as reclusive homebodies, happy to pop out for meals and the odd leg stretch. Provide enough depth and they'll reward you with charming, if occasionally elusive, behaviours.

Females of this species are true masters of longevity, commonly reaching 15–20 years in captivity if well cared for. Males, as is sadly typical in the tarantula hobby, get the short end of the stick—maturing faster and only rarely living more than 4–5 years, often less once grown. The disparity is striking, but that’s part and parcel of spider life. Regular, stable care extends lifespans and keeps your megaphobema in fighting fit form for years—a long-term pet (or flatmate) if you play your cards right!

Patience is not just a virtue—it’s a requirement with Megaphobema robustum! They grow at a slow to medium rate, so don’t expect tank-busting size overnight. Youngsters can take years to reach a respectable size, with males bolting ahead after a certain age (much to their own short-lived glory), while females dawdle along but ultimately live and grow for considerably longer. Temperature, feeding, and humidity all play a part in keeping growth healthy but not rushed.

Known as a bit of a diva in the tarantula world, Megaphobema robustum can be skittish and defensive, but seldom outright feisty unless riled. They’re not built for speed and prefer to rely on their bulk and showy warning displays rather than hurtling about the place. If startled, expect some fancy footwork, drumming and stridulating, rather than a mad dash. Regular disturbance will see them retreat or make themselves look big, not chase you around! In the hobby, they’re respected as impressive display spiders best left to their own devices.

Megaphobema robustum prefer a temperate, steady 22–25°C, mimicking the warmth of the South American rainforest. They tolerate a little wobble either side—think a comfortable British summer’s day, without the unpredictability. If your home regularly dips below 20°C, a gentle heat mat on the side of the enclosure (never underneath, mind!) can help maintain toasty conditions, but aim for a natural day-night variation. Avoid overheating—these spiders do not adore heatwaves—and make sure there’s always a temperature gradient so your tarantula can choose its own comfort zone.

Aim for 75–85% relative humidity, which means dampening part of the substrate (not flooding it!) and providing a generously sized water dish at all times. Misting one side of the enclosure every few days keeps the levels up, but ensure good airflow—ventilation is just as vital to prevent stuffiness and mould. Too much wetness leads to drama: soggy substrate is the archnemesis of healthy tarantulas. The goal is moist, never swampy; monitor regularly, and your spood will thrive.

While not the most clandestine of tarantulas, Megaphobema robustum is a bit of a part-time recluse. Juveniles are bolder, often spotted clambering about, while adults increasingly embrace the hermit lifestyle. Peak viewing time is dusk, when these nocturnal fluffballs venture out for food or a stroll. They might seal themselves in pre-moult, but when visible, their sheer size and unique colouration make quite the impression. Think of them as a statement piece with the occasional surprise guest appearance.

Not exactly the Banksys of the spider world, Megaphobema robustum aren’t big on extravagant webbing. Expect the odd silk mat near their lair, or a bit of reinforcement around a burrow or hide. They use webbing mostly for practical household tasks—lining retreats, laying down a dining mat, or prepping for moults. If you fancy a spood that crafts intricate silk curtains, look elsewhere; but for a subtle decorator, they fit the bill.

Megaphobema robustum have hearty appetites, befitting their hefty frames. Slings will happily devour pre-killed pinhead crickets or fruit flies offered twice weekly, while juveniles and sub-adults can move up to small roaches, mealworms, or larger crickets every 5–7 days. Adults, being proper units, take down dubia roaches or adult crickets once every one to two weeks. Don’t overfeed—no one wants an overweight tarantula or a pest infestation. Remove uneaten prey within 24 hours, especially during pre-moult. Fun to watch during feeding: they’re dramatic eaters, sometimes wrestling their meal with flair. Growth is slow and steady, so be patient, and always have a water dish topped up for optimum health.

Give Megaphobema robustum room to stretch—an adult needs at least a 40x30x30cm enclosure. Provide 15–20cm of slightly compacted, moisture-retentive substrate (think coco fibre and topsoil blend) for burrowing opportunities. Top it off with cork bark or half logs for hides, a generous water dish, and a mix of fake and live foliage for that tropical spa feel. Lids must be secure and ventilation above and along the sides is a must to prevent a sauna from developing. No sharp décor or gravel, please; they’re heavy-footed and need cushioned landings. Avoid any under-tank heat—side heating is safer if absolutely needed. Night-time temp dips are fine (and mimic nature), so don’t stress.

Megaphobema robustum is best suited to keepers with some hands-on (well, not literally!) tarantula experience. Their fussier humidity and size mean they’re not quite starter spiders, but for an enthusiastic intermediate they’re a rewarding challenge. Newbies might find them a bit demanding, while more seasoned keepers will enjoy their quirks, their defensive pageantry, and their titanic presence. In short: not ‘hard’, but best avoided as your first ever spood.

Megaphobema robustum is quite simply a star attraction—massive, striking, and with a reputation for quirky defensive behaviour rather than outright aggression. For those with some spider experience, they’re endlessly rewarding: not impossibly tricky, but just demanding enough to keep you sharpening your skills. Watching them barrel about, bulldoze substrate or stridulate at shadows is as entertaining as it is impressive. Humidity and space are their main needs, but get those right and you’re in for a long-term, sometimes mysterious, always magnificent flatmate. Not for the absolute beginner, but a must-try for any hobbyist ready for something a bit different—and a lot bigger.