Scientists found the arachnids within an isolated patch of southwestern rainforest, ringed by tea and rubber plantations. Living in tubular, silk-lined burrows, they are fast and aggressive, seizing unlucky insects that wander too close to their underground lairs. Measuring roughly five inches from tip to tip, these spiders are not exactly small, nor are their brilliant blue patches particularly subtle.

In fact, it’s these snazzy blue colors that first caught biologist Ranil Nanayakkara’s attention, and flagged the critters—now named Chilobrachys jonitriantisvansicklei—as potentially new to science. (Read why science still can’t explain some blue tarantulas.)

“When we first spotted them I was in awe, lost for words,” Nanayakkara says of the decked-out females. “The males,” he notes, “are smaller