On a recent trip to the Amazon, entomologist and wildlife photographer Piotr Naskrecki got up close and personal with the world’s largest (by mass) spider: Theraphosa blondi, otherwise called the Goliath bird-eating spider.

T. blondi is a species native to the Amazon, specifically the rainforest areas of northern South America. At one foot long, weighing almost half a pound, these dinner-plate-sized monsters softly whoosh across the rainforest floor. They primarily eat lizards, toads, and the occasional bird. Females, who have a lifespan of almost 30 years, eat the males shortly after mating.

Naskrecki, a renowned scientist and author of over 30 papers, had been studying katydids in the rainforest when he encountered a T. blondi in the course of his field research.

“First this is what I thought I saw – a big, hairy animal, the size of a rodent. But something wasn’t right,” wrote Naskrecki in a blog post. “Before that second was over I was lunging at the animal, ecstatic about finally seeing one of these wonderful, almost mythical creatures in person.”

“Every time I got too close to the birdeater it would do three things. First, the spider would start rubbing its hind legs against the hairy abdomen. ‘Oh, how cute!’, I thought when I first saw this adorable behavior, until a cloud of urticating hair hit my eyeballs, and made me itch and cry for several days,” Naskrecki added.

He also described how the spider “hissed” at him, then reared up to show a pair of enormous fangs. These fangs are capable of crushing a rodent’s skull. The hissing noise was made by rubbing its bristly hairs together, and is considered a first sign of defense.

Naskrecki wrote, “The venom of a birdeater is not deadly to humans but, in combination with massive puncture wounds the fangs were capable of inflicting, it was definitely something to be avoided.”

His adventures were detailed in his blog, where he encountered another T. blondi the next week. This time, he wrote playfully: “It’s just another Goliath birdeater. Aren’t you a cutie pie?”