Antilles Pinktoe Tarantula (Caribena versicolor)

Physical description and identification

The Antilles pinktoe is a medium-sized arboreal tarantula from the Lesser Antilles. For most of its published history it was called Avicularia versicolor, but a 2017 revision of the Aviculariinae moved it, together with the Puerto Rican pinktoe, into the new genus Caribena. Older books and labels using the old name refer to the same spider.

What makes it instantly recognisable is that it looks like two different species over its life. There is no other tarantula whose juvenile and adult colours differ so completely.

Adults

• Size: adults reach roughly 11–15 cm (4½–6 in) across the legs, with females larger and heavier than males. Body length is about 5–6 cm.
• Colour: the carapace is metallic green to teal, the abdomen reddish to orange-brown with dark hairs, and the tarsi — the "toes" — pale pink. Over all of it lies a purple or violet iridescence that appears and vanishes with the angle of the light, which is what versicolor, "changing colour", refers to.
• Build: typical of arboreal tarantulas — lighter and longer-legged than a ground-dwelling species, with broad, densely scopulate feet that grip smooth bark, leaves and glass. These are climbers, and a fall from height can rupture the abdomen of a heavy adult.
• Urticating hairs: present, but of the contact-release kind found in this subfamily rather than the flick-into-the-air kind used by ground-dwelling New World tarantulas. The spider has to rub its abdomen against an attacker for them to transfer, so irritation usually follows handling rather than merely being nearby.
• Sexes: mature males are slimmer, with longer legs, swollen palpal bulbs and hooks on the front legs. They also lose much of the red on the abdomen at the final moult.

Eggs and egg sacs

The female builds her egg sac inside her silk tube and keeps it with her, turning it and shifting it towards warmth, rather than leaving it exposed. Sacs typically hold between fifty and two hundred eggs and take about six to eight weeks to develop.

Spiderlings

Spiderlings are the reason this species is famous. They emerge a vivid metallic steel-blue with a black herringbone or fir-tree pattern on the abdomen, and they lose it gradually — the blue fades and the green, red and pink of the adult appear over successive moults across the first year or two. They stay in the mother's retreat only briefly before dispersing to build small tubes of their own.

The web

The retreat is a dense silk tube, often shaped like a funnel or a sock and usually open at both ends so the spider can bolt out of either. It is built against a trunk, inside a bromeliad, among palm fronds or in a hollow, and the spider spends most of its life inside it. It is a home, not a trap: prey is taken on the silk sheeting around the entrance or on the bark outside. See our guide to spider webs for how retreat silk differs from a snare.

Where the Antilles pinktoe tarantula lives

Caribena versicolor is native to Martinique and Guadeloupe in the Lesser Antilles — the eastern arc of the Caribbean, several hundred kilometres north of the South American mainland rather than just off its coast, as is sometimes written. Its only close relative, the Puerto Rican pinktoe, occupies the Greater Antilles to the north-west.

The habitat is humid forest, from lowland woodland up into the montane rainforest on the volcanic slopes. The spiders occupy tree trunks, hollow limbs, the leaf axils of bromeliads and the crowns of palms — anywhere that offers an anchored, sheltered cavity a few metres above the ground. They also settle readily on outbuildings, fence posts and garden trees at the forest edge.

Because the species is restricted to two islands, its population is inherently vulnerable to habitat clearance and to hurricanes. It has not been assessed by the IUCN and is not listed on CITES, unlike the Mexican Brachypelma tarantulas or the Asian ornamentals; most animals now in captivity are captive-bred rather than imported.

Are Antilles pinktoe tarantulas venomous?

Yes, in the way every tarantula is: the venom is for subduing insects. It is not medically significant to people, and no serious reaction has been documented from this species or from any other member of the pinktoe group. The word to use is venomous, not poisonous — the spider injects its venom and is perfectly safe to touch.

The urticating hairs deserve a mention of their own, because they are the part most people actually react to. In this subfamily the setae are short and released by direct contact, so a spider that has walked over a hand, or an enclosure being cleaned, is a more likely source of irritation than a spider sitting a metre away. The result is itching and a red rash lasting a day or two.

Can Antilles pinktoe tarantulas bite?

They can, but bites are rare. This is a nervous rather than a defensive spider: its reflex when startled is to sprint, to leap — a pinktoe can clear a surprising gap, roughly 30 cm, from a standing start — or to fire a jet of faeces at whatever alarmed it. Rearing up and biting comes far down the list.

When a bite does happen it produces local pain like a bee sting, minor swelling and two puncture marks. Wash the site, use a cold pack, and watch for infection rather than for venom effects.

Ecological importance and behavior of the Antilles pinktoe tarantula

The Antilles pinktoe is a nocturnal ambush predator that rarely leaves the immediate area of its retreat. It sits at the tube entrance after dark with its front legs on the silk, takes an insect that lands or walks within reach, and carries it back inside to feed.

Diet: chiefly flying and climbing insects — moths, crickets, grasshoppers, cockroaches, beetles — with the occasional small lizard or tree frog for a large female. On Caribbean islands, where many insect predators are absent, arboreal tarantulas are a meaningful part of the canopy food web.

Natural predators: birds, snakes, larger lizards and spider-hunting wasps, plus rats and mongooses introduced to the islands, which take a heavy toll on ground-level and low-trunk invertebrates.

Ecological role — with a correction: pinktoes are sometimes credited with pollinating plants and dispersing seeds as they move between trees. There is no evidence for that, and it is not something a tarantula does. Their genuine ecological contribution is straightforward predation on insects, and the shelter that abandoned silk tubes provide for other small invertebrates.

Are they colonial? Not really. Several individuals are often found in one tree or in a cluster of bromeliads, which is why the species is sometimes called communal, but that reflects an abundance of good retreat sites rather than social behaviour. They are solitary hunters and will cannibalise one another when crowded.

Seasonal behaviour and lifespan: mature males abandon their retreats to search for females and rarely live more than two to three years in total; females live around ten to twelve years and may produce a sac in successive seasons. The whole life cycle runs through a series of moults, during which the spider seals itself inside the tube.

Similar tarantulas and how to tell them apart

Quick facts

Did you know?

• The species epithet versicolor means "of changing colours" — a name that turned out to describe both the iridescence of the adult and the complete colour change from blue spiderling to green-and-red adult.
• Pinktoes are among the very few tarantulas that defend themselves with a jet of faeces, fired accurately at a disturbance from the entrance of the retreat.
• The 2017 revision that created Caribena also trimmed Avicularia from a long list of doubtful names to about a dozen valid species and erected a third genus, Ybyrapora, for a Brazilian group.
• In captivity this species is kept in tall, well-ventilated enclosures rather than humid sealed ones; stagnant, saturated air is the classic cause of losses, and cross-ventilation matters more than raw humidity.

In summary, the Antilles pinktoe is a small-island arboreal tarantula with two entirely different colour schemes in one lifetime, a silk tube instead of a web, a harmless bite and a habit of running rather than fighting. Admiring it through glass, or in a Martinique tree, is the whole point of the species.