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August 17, 2012 | 19
Meet Trogloraptor, fearsomeness incarnate. The creature more than lives up to its name—it is, in fact, an eight-legged showcase for scientific novelty. The spider somewhat resembles the brown recluse, famed for its flesh-necrotizing venom—but at four centimeters, Trogloraptor is about twice as large. In fact, this spider is an entirely new critter—just look at those legs, each ends in a curved, scythelike claw. Citizen scientists and arachnologists have uncovered these spiders in the caves of southwestern Oregon and old-growth redwood forests. As they report in ZooKeys, the discovery of Trogloraptor is a taxonomic wonder that establishes a new family, genus and species in the spider family tree.
Troglo's story begins with citizen scientists in the Western Cave Conservancy who spotted the strange spider in Oregon's caves. They sent specimens to researchers at the California Academy of Sciences where entomologist Tracy Audisio, a research fellow at the California Academy of Sciences, puzzled over the new find. After approaching every member of the arachnology lab, she and Charles Griswold, the academy's curator of arachnology, took the finding to arachnologists around the country. They combed through comparative anatomy, fossil records and genetic analyses in their efforts to place the new spider, only to conclude that the cave dweller has a totally unique lineage.
The closest known relatives to this clawed creepy-crawler come from the Oonipidae, or goblin family of spiders. Trogloraptor's anatomy reveals, however, several ancient features, including a primitive respiratory system that sets these spiders apart. The researchers believe the Trogloraptor family separated into its own evolutionary branch some 130 million years ago.
The spider's name is Latin for "cave robber," a reference to its habitat and rapacious-looking talons. As for the claws, there's another genus of spiders with similar appendages, the Spelungula of New Zealand. These cave spiders are otherwise distinct from Trogloraptor, suggesting their claws evolved independently. Troglo's claws are barbed on their underside and may be designed to clamp shut on passing prey. The researchers believe that, like Spelungula, Trogloraptor dangles from cave ceilings with legs akimbo, then snaps its claws like a trap when small flies pass by. The spider's exact prey, however, is unknown. Before arachnophobes get too nervous, though, Griswold notes that the spiders are not likely to be venomous to humans. In fact, they're quite shy. Working with live specimens, he's observed that their behavior is distinctly unaggressive and their main interest is escaping the light as quickly as possible.
Researchers at San Diego State University have spotted juveniles in old-growth redwood forests. Although more study is needed, these specimens are likely a different species from those found in the caves. Griswold notes that given the age of this family and the former distribution of redwoods in North America, it's possible that other Trogloraptor species could inhabit caves across the country. "They could be living in caves in Nevada," Griswold says. "They may have been hiding there since the Pliocene or Miocene." Given their fragile habitats and ancient history, these creatures warrant protection as evolutionary marvels.
--Daisy Yuhas
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19 Comments
Add CommentI only stopped screaming long enough to type this sentence.
Reply | Report Abuse | Link to thisHaha! I'm no fan of spiders, but as the author of this article states, these are evolutionary marvels. I do appreciate a mean looking spider that is basically harmless to us though.
Reply | Report Abuse | Link to thisThis brings a whole new meaning to the message when my mouse strayed onto the image: "click for larger version"
Reply | Report Abuse | Link to thisOh no, no thank you please.
I've been down into some caves in southern Oregon and or northern California. And late in the evening without guide or others. I had no idea.
Is it possible, since the spider exhibits light sensitivity, that it has developed a sensitivity to light in the infrared range to help it survive in the dark environment of a cave?
Reply | Report Abuse | Link to this130 million years ago... we need to have a video clip to go with this, one that would move the continents around, show us where "Oregon" was back at the "beginnings" of this "new" family of spiders. Very impressive find.
Reply | Report Abuse | Link to thisI LIKE "poinces".
Reply | Report Abuse | Link to thisSpider's theme song:
Reply | Report Abuse | Link to thishttp://www.youtube.com/watch?v=oD1nQ1FWpoc
Spiders surely are strange creatures, and have their share of influence on the human psyche. This is a spider I photographed over a lazy weekend, I was surprised by what I saw: http://delog.wordpress.com/2012/07/17/the-spider-man-spider/. You do need to see it up close though, so click to see a bigger picture.
Reply | Report Abuse | Link to thisI love how everyone says millions of years for this or that ... when we dont have anything for a control sample ... to compare to the stuff we have today ... to show proof of age ... or how some make a living on pure conjecture ... like ... dinosaurs ... people like they roared like this ... or traveled in packs ... or man came from apes ... but there is no record of apes doing so ... since the creation of writing ... and people eat it up like its gospel ...
Reply | Report Abuse | Link to thisFair Comment.
Reply | Report Abuse | Link to thisThe thing is, there is nothing apart from weight of numbers to uphold most "faiths" and "The Theory of Evolution" is just that, A Theory.
So let's just get on and enjoy life. You only get one shot at it - allegedly.
I have seen a similar spider at Oregon Caves National Monument, several miles from the initial discovery site. I've only seen it in the "twilight zone", just inside the cave entrance. At first glance they look like large cave crickets. But take a closer look. The enormous mouth, (jaws), unfold in a way reminiscent of "Alien". Gruesome! Grotesque! What does it eat?? I haven't seen any webs. Maybe there are times of the year, (spring or fall migrations), when this monster roams around - and kills at will. (Just a theory.)
Reply | Report Abuse | Link to thisCongrats to the folks who figured out that this is not you're ordinary spider.
Although it shouldn't surprise me any longer, I still marvel at the fact that anti-evolution people who CLEARLY have absolutely no idea what the word "theory" means nor any idea how science actually works would even bother to read and comment on an article at Scientific American. Did your subscription to Scientific Illiterate run out?
Reply | Report Abuse | Link to thisRe: "The researchers believe the Trogloraptor family separated into its own evolutionary branch some 130 million years ago."
Reply | Report Abuse | Link to this"Believe" seems to me a rather strange term to use on a reputedly scientific web page.
Yet, this is not the first occurrence in the world of SCIENTIFIC AMERICAN:
One has only to contemplate the magnitude of this task to concede that the spontaneous generation of a living organism is impossible. Yet here we are—as a result, I believe, of spontaneous generation. It will help to digress for a moment to ask what one means by "impossible."
[Prof. George Wald. 1954. THE ORIGIN OF LIFE.* SCIENTIFIC AMERICAN, August, pp. 46-47]
What is the evolutionary explanation for how some spiders developed claws?
Bill, it is a widely used term. It is used when there is solid evidence of a claim but not absolute proof. It is possible that new evidence will emerge that may push the date up or down or perhaps even refute the finding altogether, though the latter is unlikely.
Reply | Report Abuse | Link to thisAs far as its claws go, I would imagine that in the spider's particular niche the claws provided some sort of advantage over the others. The ones that had them may have had an easier time to get food or fend off other predators thus had its chances of surviving longer to reproduce increased.
Ungolythe,
Reply | Report Abuse | Link to thisYou would seem to be correct about believe being a widely used term in the scientific literature in my research experience. However, use of the term would not seem to indicate a high level of solid evidence. Even Prof. Wald was taken to task in the 1979 SCIENTIFIC AMERICAN SPECIAL EDITION. Gee! it only took 25 years.
Regarding proof, a well known university professor provided the following perspective:
“ No, well, a theory must be, in many senses you have to disprove things, it’s very difficult to prove anything…”
[Peter D. Ward, http://www.discovery.org/a/3421]
If memory serves, Prof. Douglas Futuyma also wrote a similar statement in his 1983 book, “Science on Trial: The Case for Evolution,” New York: Pantheon Books.
One can imagine anything concerning niches and advantages. However, unless the phenomenon is observed, all is little more than speculation.
you suck
Reply | Report Abuse | Link to thisyou suck
Reply | Report Abuse | Link to thisI have to agree with you on some level. Even being a Christian believing in the "intelligent design" theory, I take what I believe on faith because I have no proof. If you don't have proof for something, don't publish it like it's a fact....eh hem...(cough, cough) evolutionists.
Reply | Report Abuse | Link to thisYes!
Reply | Report Abuse | Link to thisEvery second that ticks by is gone!
You don't get it back again.