Theraphosidae sp. Yurimaguas

Yurimaguas is a town on the Huallaga River in Peru's Loreto region, on the edge of the Amazon lowlands where the Andes give way to rainforest. It lends its name to Theraphosidae sp. Yurimaguas, a tarantula that has yet to receive a scientific description or a place in any genus. The hobby holds many such undescribed species, and each is an open page: the name points to a place, and keepers write the rest.

Its looks stop you in your tracks: a grown specimen (pictured) is steel-blue all over, with a metallic sheen across the carapace, abdomen and long legs, and pale bristling hairs throughout. Little is yet known about adult size or behaviour in captivity, and that is precisely its appeal. Starting with an L1 spiderling, the keeper watches from the first moults as the colours change, as the spider arranges its retreat and as it responds to food and surroundings. This is a spider for observation in the enclosure, and good husbandry notes have genuine value for other enthusiasts.

L1 spiderlings do best in a small container with a few centimetres of coconut fibre, a small hide and good ventilation. Its origin in humid Amazonia suggests keeping part of the substrate lightly moist with regular misting and part of it dry, so the spider can choose where to sit. Spiderlings drink from droplets on the walls and substrate; a water dish comes in only for larger specimens. Room temperature is sufficient. Offer small prey sized to the spider.

This is one for keepers with a few species behind them who like to hold something that is not on every list. A species from the Peruvian Amazon, still without a species name and with questions that only the next moults will answer. For collectors of undescribed species, it is a piece of genuine discovery.