Mystery over four spiders found in Miami is solved
It’s an entirely new ‘trapdoor’ species
When a previously unknown creature is found in South Florida, it’s usually an invasive species brought into the region from an exotic location.
Not so with four mysterious spiders found near Zoo Miami over the past decade. These guys are just extremely elusive.
And now, a researcher at Piedmont University in Georgia determined that the four male spiders are members of a new species called the Pine Rockland trapdoor spider, named for the forest surrounding Zoo Miami and the way the spiders hunt.
Zoo employees have found four of the quarter-sized spiders in the area since 2012.
“But we’ve never found a female,” said Frank Ridgley, head of Zoo Miami’s conservation and research department. “So, since 2012, we’ve found four males and that’s it.”
But Ridgley said where there are males there must be females, which are likely to be two to three times larger than the males.
Pine Rockland trapdoor spiders only venture a short distance from where they were born, Ridgley said. They burrow into sandy soil to make a home and live in that same burrow for their entire lives, possibly as long as 40 years.
A lid atop their burrow provides shelter and camouflage. The Pine Rocklands
are ambush predators and Ridgley thinks they hunt by waiting for prey to come near the burrow, then pouncing out of the trap door.
There are other species of trapdoor spiders, mostly found in the southwest U.S. “They’re all in the family that’s closely related to tarantulas,” Ridgley said, “and you can kind of see that.”
Although it is unknown if the Pine Rocklands have natural predators, Ridgley said other trapdoor spiders must watch out for parasitic wasps that might detect the spiders through a chemical signature.
“They can actually pierce the little lid on top of their tunnel they use to hide and lay an egg in there, or on the spider itself, and then it uses the spider to raise like its
babies,” he said. “It’s a horrible-sounding process, but it’s a parasitic wasp and that’s one kind of predators we know. But is anything able to detect them and dig them up out of these burrows? I don’t know.”
Ridgley said Zoo Miami employees find some type of rare species, both animals and plants, about once a year. He said about 12 or 15 years ago, a Miami tiger beetle was found in the same area where the Pine Rockland Trapdoor Spider was found. The beetle was thought to be extinct for about 80 years, Ridgley said.
No one is yet sure how many Pine Rocklands there are, but Ridgley said he suspect there are very few.
“We would just assume that they’re likely already very imperiled,” he said.