Yellow Arachnids of Texas

Take a look at the U.S. Endangered species list, arachnid section. Out of twelve arachnids, eleven of them fall into the form of “X Cave Y,” where X is the name of a cave, and Y is the type of arachnid. Ten of these are from two counties in Texas. Since these aren’t discussed in depth separately, we’ll talk about the whole bunch. They are, in no particular order, the Bee Creek Cave Harvestman (Texella reddelli), the Bone Cave Harvestman (Texella reyesi), Robber Baron Cave Harvestman (Texella cokendolpheri), the Braken Bat Cave Meshweaver (Cicurina venii), the Government Canyon Bat Cave Meshweaver (Cicurina vespera), the Madla's Cave Meshweaver (Cicurina madla), the Robber Baron Cave Meshweaver, (Cicurina baronia), the Tooth Cave Pseudoscorpion (Tartarocreagris texana), the Government Canyon Bat Cave Spider (Neoleptoneta microps), and the Tooth Cave Spider (Leptoneta myopica). For your viewing pleasure today, we have the Bone Cave Harvestman, simply because it has a cool name (and if any Metalheads reading this are at a loss for a band or album name, you’re welcome).



Each of the arachnids is predatory, feeding on smaller cave-dwelling invertebrates. They are eyeless, and paler than its superterranian counterpart, often becoming orangish or yellowish. Otherwise, the spiders (meshweavers included) are similar to the everyday house spiders, and the same goes with the harvestmen, though I had to look them up to find that harvestman was another name for daddy longlegs. Pseudoscorpions, which I’m not sure how many people are familiar with them (I’m not), look much like, well, scorpions, just tailless, with small venom glands in their claws.

What is this cave habitat that contains all these endangered species, and why are there so many endangered arachnids in such a small area (relatively, we’re talking about Texas here)? The Texas karst is a limestone area that, due to the erosion of softer rocks, has formed extensive cave systems. Since they have formed (and continue to do so, they won’t stop for us) by water flow, anything dumped on the surface goes right through to all of those places where eyes are luxury items. While pollution is certainly a problem, the major issue is development encroachment, which has the possibility of destroying the area around caves or the caves themselves, or changing the temperature of the cave, which has been constant since, oh, the last ice age. Invasive plants can bring in red fire ants, which compete with the arachnids for food and sometimes prey on them.

There’s another reason for the density of endangered cave arachnids: the density of spelunking entomologists. Like it or not, much of the information about endangered species comes from a few people looking for specific species. Since they know exactly what they’re looking for, they can determine that these species are endangered, and go through the rigmarole of getting them listed. There are tons of endangered species running all over the place, but since no one’s described them, or looked closely enough at them, they go unnoticed.

No One Like You

For October, Jonathan Wojcik of Bogleech agreed to do a guest post for Endangered Ugly Things. Check out his site for all the information you could ever want about monsters, real or imagined. Enjoy!
-Garfman

There are over a hundred thousand named Arachnids crawling around on our planet's surface, and America is more aware of them this time of year than any other season. Famous though they are, these ubiquitous terrestrial predators are seldom evaluated for their conservation status, and the exceptions have consisted almost entirely of spiders - really only one of several strange and incredibly ancient Arachnid groups.

Image by Gilles San Martin

Currently, there are at least two non-spider Arachnida recognized as threatened, and both of them belong to the family Lycosidae, or "pseudoscorpions." Though found virtually everywhere, these mostly blind predators go largely unnoticed due to their subterranean habits and incredibly small size - so small you can find them preying upon mites, lice and springtails between grains of soil, under the wing cases of beetles, in the fur of mice or between the pages of dusty, moldy old books. Many species will even use far larger, flying insects as transportation, grabbing into their leg hairs with a single claw and letting go at the next landing.

As their names imply, pseudoscorpions are entirely separate from the true scorpions, lacking the venomous tails but bearing very similar pincers which, in many species, can inject venom through the lower thumb-like claw. As an added bonus, they can also regurgitate a corrosive enzyme over stunned prey and secrete silk from their jaws, usually used to build igloo-shaped cocoons in which they molt and overwinter. Mating typically involves a "dancing" ritual where the male, locking pincers with the female, guides her over a sperm packet he lays on the ground. Like many other arachnids, females will carry their babies on their backs until tough enough to fend for themselves.

These minute animals have existed in more or less the same form for over 380 million years, but at least two species could disappear on us at any moment.  Known endangered Lycosids include Fissilicreagris imperialis and Tartarocreagris texana, the Empire cave and Tooth Cave pseudoscorpions. Like many other creatures you can read about on EUT, these troglobytes are completely unique to their respective cave systems and have adapted to survive in no other environment. Any unusual activity can be disastrous for cave dwelling organisms; even a few careless spelunkers or a trickle of urban runoff can disrupt conditions that have remained unchanged for eons.

A staggering portion of the human race suffers from unreasonable levels of terror associated with eight-legged arthropods, but it's not fair to let a widespread phobia cloud our concern for the plight of any species, large or small. If more of us could get past our fears and appreciate just how weird, cool and useful the Arachnids are, we might be seeing quite a few more of them not only listed, but actively protected. Right now, eyeless micromonsters are dancing in each other's arms in pitch darkness, and surely deserve as much as any other animal to continue doing so for ages to come.

The White Tent The Raft

It’s been a while since an arachnid has graced this blog, and since I only have three arachnid posts total, it’s high time I add to it¹. Everyone keeps calling it “one of Europe's largest, most beautiful but least common species of spider.” Hate to break it to you guys, but it’s still a spider, and most people don’t like spiders.


Yeah, I think it’s pretty too. But look how surprised that fish is!

The Fen Raft Spider (Dolomedes plantarius) is not an aquatic spider--there’s no such creature². However, they aren’t aquatic in the same way a Water Strider isn’t aquatic. Just because you can’t swim doesn’t mean you have to get out of the pool—or rather, off the pool. They skate on top, using surface tension to float across the bogs and swamps; hence the name “Fen Raft”.

These spiders are found throughout in wetlands throughout Europe, with a fairly spotty distribution. They do not build webs to hunt, preferring to wait on a stem with their front legs touching the water’s surface. When they feel a vibration, BAM! Dinner is served. Main courses typically include aquatic insects, water striders, and less frequently, fish, like our surprised friend shown above.

The water also comes in handy when a male Fen Raft Spider wants to woo the ladies. Courtship involves drumming the water until the couple meets, when they both begin to bob slowly to each other. Mating is quick, likely because it is not unheard of for the male to become a protein source. After laying the eggs, the female carries the egg sac under her fangs for about three weeks. After hatching, the young spend a week growing up in a web-nest that’s constructed and guarded by mom.

It seems that wetlands are disappearing everywhere, and therefore, so are the Fen Raft Spiders. The remaining wetlands are getting more and more pollution problems, and all evidence suggests that these spiders require clean water. There’s certainly hope though. Britain has pulled out all the stops trying to protect their two populations from dying out, and frankly, it seems to be working.

¹Here’s a challenge for you readers: can somebody find me an endangered whipscorpion? That would be cool.
²These are not spiders.

"Will You Walk Into My Parlor?"

Sorry for such a late post. I don’t have any good excuses; I’ve just been slacking. A few weeks ago, Greg (who also suggested the Siaga Antelope) suggested an EUT for me¹. I found out that its story is unavoidably attached to another Endangered Ugly Thing.












This is the suggested animal, the Kauai Cave Amphipod (Spelaeorchestia koloana). It’s a blind, terrestrial, shrimp-like crustacean that inhabits the small caves formed by gas escaping through the Hawaiian lava². It lives happily on the detritus to be found in those caves. The Kauai Cave Wolf Spider (Adelocosa anops) inhabits the same habitat, except it lives happily on the Cave Amphipods to be found there. They’re only found in about five different locations on the island of Kauai, most of which are on private property.

Everyone seems to find it strange that the government would protect both a predator and its main prey item. Someone even did a cartoon on it, and, quite frankly, I don’t often see people trying to anthropomorphize blind amphipods. Or amphipods of any kind.

Look, it’s not that strange. The Kauai Cave Amphipod is not endangered because the Kauai Cave Wolf Spider eats it. The amphipod has had millions of years to evolve defenses against the spider. They’re both endangered because of Hawaii’s³ rapid development. Y’know, paving over the lava, agriculture, and heavy use of insecticides for invasive species control (and other less noble goals). Protection is just starting, as they only got added to the list in 2003, though they’ve been working on restoring the caves since 1995.

¹Please, please, please keep sending in those suggestions. It makes life so much easier for me.
²Yes, I know I just wrote about a Hawaiian EUT. See above footnote.
³I’m trying to decide if “Hawai’i’s” would look weird. Yeah it does.

Does Whatever A Spider Can

After the post on most of the arachnids on the US List, I couldn’t help but look at the non-cave spider. I will get to your suggestions¹, but I’m still trying to spread the love to all the taxa².















The Spruce-fir Moss Spider (Microhexura montivaga) is a small (3-5 mm) member of the tarantula group. They live above 5,400 feet in the Appalachian Mountains in North Carolina and Tennessee, where it can get colder and snowier than many spiders mind to handle. The prominent vegetation of these areas (surprise, surprise) is Frasier fir and red spruce, and the spiders inhabit the mosses found in association with those trees.

Like most tarantulas, the moss spider is an ambush predator, feeding on arthropods smaller than itself. This does not mean they don’t make webs; they weave tunnel-shaped nests between the rock and the moss. After mating, the males make a run for it, since many female spiders find the male to be a readily available protein. Females stay with the egg sac until it hatches, and will carry it around if she’s disturbed. When the spiderlings³ hatch, they disperse to other areas by a process called ballooning⁴, where the babies extend a strand of silk to be caught by the wind.

They’re not terribly sure why the spruce-fir moss spider is endangered, though there are some good ideas. The primary suspect: the balsam wooly adelgid, an invasive insect that attacks fir trees, which mess up the spider’s habitat. There’s a possibility of throwing out the baby with the bathwater, as it’s possible that the insecticide used to kill these tree-borers could also be killing the spiders.

The Louisville Zoo is working on a breeding program, though there are no cute little spiderlings yet. I’m finding enough information that I know someone is worried about the species. Heck, someone even named a debugging program after it.

¹I’m really looking forward to learning more about the antelope that looks like something out of Star Wars.
²There are two lichens that I might have to write something about to spread the love even further.
³This is the actual term for a baby spider. Another Cute Endangered Ugly Thing design?
⁴Popularized by the animated version of Charlotte’s Web.