Information

Identification of this spider?


I find these in forests in Oregon, western half, though they're probably on the eastern half as well. They live under pieces of wood and bark, and have a small web across the ground. Mine will eat crickets, but I think they eat carpenter ants, termites, and maybe pillbugs/sowbugs. It seems about an inch long, red on the thorax and legs, and dark grey and slightly hairy on the abdomen. The closest to this spider I've found is sowbug killers -- they're in my backyard, but they're smaller then this spider and also are a light tan on a hairless abdomen, with lighter colored legs. The fangs also seem different shapes but I'm not sure about that.


This is very likely a species in the Amaurobiidae superfamily, and I agree appears to be Callobius severus (the hackled-band weaver or the hackledmesh weaver).

Source: Bugguide.net

Source: Kyron Basu 2012

Moldenke et al. 1987 provide a key to spiders of the Pacific Northwest. Importantly, they note:

adult genitalia are necessary for identifying species and separating Callobius from Amaurobius.

  • For example, here is a picture of Amaurobius ferox (Hackledmesh Weaver)

© Danny Steaven 2008

  • I've seen numerous sites conflate this species with C severus and actually I've seen sources that identify them both as the "Hackledmesh Weaver".

So although the OP's specimen strongly resembles Callobius severus, a scope is necessary to truly identify to species. This Penn State page provides good information regarding these similar looking species in the superfamily.

Callobius and Amaurobius species have similar life histories and behaviors. They are most often found in damp locations under bark, leaf litter, and stones, as well as in woodpiles and other protected areas.

Stephen Ellis Lew (2011) produced an atlas to the genitalic morphology of the Callobius genus, and he proposed a morphological diagnosis that is more consistent with principles of homology than those previously in use. [See the link for his dissertation on the subject].

Callobius severus

Description:

  • Cephalothorax and legs = reddish to dark brown [Source].
  • Abdomen = dark to light grey with fine hairs; often with large, bilaterally mirrored paler spots.

Ecology:

  • Nesting woodland species commonly seen in the Pacific Northwest

  • McIver et al. (1990) suggests that this species of spider is one of many that is characteristic of young forests.

Is it Dangerous?:

  • Not according to this Penn state website:

The one verified record of a bite by an immature Callobius species resulted in pain, itching, swelling, redness, and nausea.

  • Vetter & Antonelli provide evidence for how to differentiate this species from the "more dangerous" hobo spider.

in the side view, the palp of Callobius males has large, conspicuous, pointed projections (Fig. 7).


It look like Callobius severus to me.


I agree with the above that the spider is probably Callobius severus, especially since you found the spider in a forest in Oregon.

The spider in found in parts of the United States and Canada with nests most widespread in the U.S. state of Washington and the states bordering Washington, making them most common in America's Pacific Northwest region.


Camel Spider

The camel spider is a common name for a large number of species in the order Solifugae. Also known as wind scorpions or sun spiders, these creatures are neither a scorpion nor a spider. While they are still in the Class Arachnida, they display traits of both scorpions and spiders.

Like scorpions, the camel spider has a distinctly segmented opisthosoma. However, it does not have an elongated tail with a stinger. Like spiders, the camel spider uses its pedipalps (foremost appendages) to search for and manipulate prey items. Camel spiders have 8 legs like all arachnids, though their pedipalps are so large that it looks as if they have 10 legs.

The chelicerae of a camel spider are much more massive than those in most arachnids, though they do not contain venom like many spider species. Instead, these powerful appendages are used to cut and tear their prey into small pieces, which are then liquified and swallowed. These chelicerae are powerful enough to bite through human skin, so camel spiders should not be handled. However, they are not nearly as dangerous or scary as the internet has made them seem.

Common Camel Spider Myths Debunked

The camel spider was relatively unknown to most people until the early 2000s. Despite the fact that the order Solifugae is distributed across the globe and that most areas have more than 1 species of camel spider, these small predators were relatively unknown until soldiers fighting in the Middle East began to send back manipulated pictures of “giant” camel spiders. By holding these arachnids closer to the camera, it gave the appearance that they were several feet in diameter.

In truth, camel spiders reach a maximum of about 6 inches in diameter and are almost completely harmless to humans. In the desert, these predators sometimes follow the shadows of larger animals – giving the impression that they are chasing or preying on a camel or a human. However, this is simply untrue.

Like spiders and scorpions, members of the order Solifugae also have pedipalps – leg-like appendages that are not used for walking. Instead, these foremost appendages are used solely for finding, capturing, and manipulating prey. The pedipalps are covered in small hairs, which allow a camel spider to feel everything that the pedipalps touch.

Fear of Arachnids

Interestingly, the fear of arachnids is an inherent reaction in many primate species, not just humans. Evolutionarily, animals evolve to fear or avoid species that may be dangerous. However, there are millions of species on the globe and so animals must generalize what features they use to identify a dangerous species. So, because there are some 8-legged species that have the potential to harm a human, most humans retain a fear of all crawling insects.

While this fear is irrational in the case of the camel spider, it is nevertheless ingrained in many cultures and populations. Though this evolutionary fear may have helped our ancestors survive and reproduce in ancient times, modern science makes it easy to distinguish species that are actually dangerous. Much like a cat will react to a cucumber as if it were a snake, most people are scared of insects, arachnids, and other arthropods simply because of a deeply engrained evolutionary response. Once you get to know the camel spider, you will see it is not a threat and is actually an amazing group of species with incredible adaptations.


Biology of Spiders

Spiders are not insects. They are close relatives of ticks, mites and scorpions, which all belong in the group called arachnids. Unlike insects, which have three main body sections and six legs, spiders have two body sections and eight legs (Figure 3). The eyes, mouthparts (Figure 4) and legs are found on the front section of the body, known as the cephalothorax. The second section, the abdomen, bears the parts of the respiratory system (spiracles and / or book lungs depending on the type of spider), the digestive and reproductive systems, and the external organs used for spinning silk or webbing. Most spiders are identified by size, color, markings on the body, and the number (usually six or eight) and arrangement of eyes. Female spiders wrap their eggs in a silken spun sac. Some spiders carry this egg sac, while others deposit it somewhere within their nest. Hatchling spiders (spiderlings) often produce a silk thread that allows them to disperse by "ballooning," i.e., being blown by wind currents to other areas.

Figure 3. A spider's body is divided into two parts. The cephalothorax is the fused head & thorax. The legs are located on the cephalothorax. The abdomen is similar to that of insects.

Department of Entomology, University of Nebraska-Lincoln

Figure 3. A spider's body is divided into two parts. The cephalothorax is the fused head & thorax. The legs are located on the cephalothorax. The abdomen is similar to that of insects.

Department of Entomology, University of Nebraska-Lincoln

Figure 4. Spiders have mouthparts known as "chelicerae" on which you will find their fangs.

Department of Entomology, University of Nebraska-Lincoln

Figure 4. Spiders have mouthparts known as "chelicerae" on which you will find their fangs.

Department of Entomology, University of Nebraska-Lincoln


UC Davis Professors Ask Public to Help Name New Spider Species

An unnamed spider species lurks in the sand dunes of Monterey County's Moss Landing State Beach and UC Davis scientists need your help naming it.

UC Davis Professor of Entomology and Nematology Jason Bond recently appeared on Assistant Professor of Teaching Joel Ledford’s Tree of Life-UC Davis YouTube channel to discuss the discovery of this new, unique species of trapdoor spider and the upcoming paper describing it.

“It is remarkable in that it occurs in a relatively narrow section of sand dunes and has no geographically close relative,” said Ledford, who is a co-author on the upcoming paper and is formally trained in spider taxonomy. “It is being placed in a new genus (Cryptocteniza), but we would like input on the specific epithet.”

Bond and Ledford are asking the public to help name the species. So Cryptocteniza ________? The blank is where your creativity comes in. The Cryptocteniza part of the name is partly derived from the spider’s “hidden nature.”

Bond discovered the unnamed trapdoor spider species in 1997 during a field expedition to Moss Landing State Beach, an area he frequented to study California trapdoor spiders (Bothriocyrtum califonicum). Trapdoor spiders are sneaky predators. They burrow underground and cover themselves with a “trapdoor” constructed from environmental materials (like sand) and silk. When prey pass by, the trapdoor spider bursts forth, snaring the unsuspecting creature and dragging it into its subterranean lair.

While digging up trapdoor spiders, Bond found a specimen unlike anything he’d seen before.

“I immediately sort of thought to myself that it looked like a new genus of trapdoor spider,” he said during his interview with Ledford.

Bond collected female specimens, but in order to complete the picture of a new species, he needed male specimens. What followed was 22 years of unsuccessful searching. But science is an endeavor of patience.

In fall 2018, a photograph of a male trapdoor spider (the species unidentifiable) was posted to the app iNaturalist. Outfitted with geographic coordinates, Bond and his team worked with California State Parks to set up traps to capture the spiders. In September 2019, they finally collected a male specimen.

“It’s really unusual to discover a new species, a new genus, in the field,” Bond told Ledford. “Those sorts of discoveries today are usually from specimens that are found in museum collections.”

According to Bond, specimens of new species can sit on shelves of museum collections for decades before a taxonomist comes along and describes it.

Bond is no stranger to naming new species. He’s named spiders after Star Wars’ characters (Aptostichus sarlacc) and even named one after talk show host and comedian Stephen Colbert (Aptostichus stephencolberti).

I was thinking it’d be a nice idea to sort of ask the public to…give us some ideas about who or what they might like to name this species,” said Bond.

Those interested in helping name the species should add their suggestions to the comments section of the YouTube video. Bond and Ledford will select the best name from the list of suggestions.


Choosing the right age and species

Some species are more active and generally interesting than others, some are calmer, some are interesting architects, others are flashy predators, some are just out and out lovely, but others are just plain boring. So, like the breed of dog, the tarantula species also matters. To choose just the right animal for your needs, try to come up with the right balance between your patience, squeamishness, and budget. If you get scared by fast moving spiders, pick a slower moving species. If you really want to pet your spider occasionally and not worry about it biting you, get a pinktoe. First, think about what age to purchase:

Spiderlings: I’ve loved raising spiderlings, rather than buying adults. In all honesty, almost my entire collection was started with inexpensive spiderlings because I couldn’t afford adults. Captive reared spiderlings are somewhat more active than adults, I’ve enjoyed seeing developmental changes in their anatomy and behavior as they mature, and it is fun to see the huge changes as a small animal moults regularly into a large animal. I have personally found them more gratifying. Most of the beautiful animals I have were 1″ in size when I bought them and they are now good sized animals. However, smaller spiders are often more delicate, more likely to die while moulting, are harder to feed (where are you going to get small flies or crickets in the winter?), and can be much shyer than the adults (or more active). If you’ve got patience, the spiderlings can be an inexpensive way to learn about tarantulas. Look at the body size on a price list and don’t choose a spiderling that is less than 1″ in size. A 1″ spider means body and legs combined to equal an inch. It is easy for that size to be exaggerated on price lists. Depending on the size of your spider, you would start by keeping them in a big pill vial, and eventually move them to larger cages. Remember that tarantulas have terrible vision and will have trouble finding the prey in large cages. Small spiders NEED to start in tiny cages, then move them to larger spaces as they grow larger.

Adults: If you are new to keeping invertebrates, you might want to start with a big, super easy adult or subadult. Adults are easier to feed, do not need quite as regular feeding, have survived to adulthood, and are bigger and easier to see. Adults are fine animals to have. They are also hardier and more likely to survive in a classroom. Adults (that you can afford) are generally wild caught, while the spiderlings are generally captive born. All of the species I am recommending are both common and commonly bred in captivity. Like the spiderlings, all tarantulas need a retreat in their cage to hide under. Adult spider probably prefer to have more space in which to move. You can keep them happily in small cages to 10-gallon tanks — just make sure that it has a secure top on it! I generally cover most of the tops of cages with plastic wrap or tape because the spider can dry out too much with a totally open screened top to its cage. In all of my cages, I have soldered or drilled cork-sized holes so that I can put crickets in the cage without the need to OPEN the top of the cage. With many species it is easy to ‘hand-feed’ crickets to the spiders through the holes without direct contact between you or your spider.

Think about the life style of your spider. Decide between an arboreal or a terrestrial species. Arboreals, or tree living species, not surprisingly like to go up and stand on the side of the cage as they would on a tree. In practical terms that means you need to provide a taller cage that allows them space to move up and down on the side of the cage, but doesn’t need a big ‘footprint’. Some arboreal species produce more silk (which can block your view), but in my experience tend to be more active. Other than the Pinktoes, they are often faster moving species. I happen to love the long legs and sleek, elongate bodies of the arboreal species and find the fatter terrestrial species to be rather clunky.

Terrestrials spend most of their time sitting on the ground. Some dig burrows which make them harder to see, but most sit in the open. Some of them are very slow moving, although some are faster. Not surprisingly, terrestrial species need more area on the ground but not much height in their cages. They need a retreat of some sort.


The science behind Spider-Man’s superpowers

The summer movie season is already in full swing, with “Avengers: Endgame” already earning more than $2.7 billion worldwide and many others hoping to cash in on global superhero excitement.

“Spider-Man: Far from Home” is the latest cinematic telling of the story of Peter Parker, the friendly neighborhood superhero who can climb up walls and is incredibly strong and agile. Parker is also a scientifically-savvy hero, making his own costumes and gear, who continues to inspire audiences 57 years after he was originally brought to life by Stan Lee and Steve Ditko.

And while radioactive spiders might not be lurking in labs giving unsuspecting students the ability to climb walls, Spider-Man’s superpowers and his synthetic webbing might not be completely out of reach. Penn Today talked with materials scientist and engineer Shu Yang to learn more about the real-world versions of these “super” materials, and how engineers in her field are inspired by biology to create manmade materials with unique functions.

When engineers see the incredible materials that come from biology, things like strong-yet-flexible muscle tendons, wall-climbing geckos, or spider silk, how do they approach the process of creating manmade materials with similar properties?

Biologists and engineers definitely have to work together. Many years ago, we made iridescent opal-like colors and said, ‘We’re mimicking the biology they have these interesting colors and we’re mimicking butterfly wings,’ but without actually knowing how bioorganisms work and why they do so.

Then we started to work with Dan Janzen and Alison Sweeney, and now we’re trying to understand convergence of biology and asking deeper questions: If you see the color, where’s the color coming from? Is it because of the morphology, or because of the chemistry? Within the same family of butterflies, why do they have different colors? Why do some plant leaves or seeds and butterfly wings have similar colors? Are they due to the same mechanism?

If we can understand why they behave this way, we can design a structure or design a chemistry to have similar functionality without taking hundreds of millions of years to make them, or taking laborious steps to make the same very sophisticated structures as biology does.

What makes spider silk such a “super” material?

There are different kinds of alignment of the silk protein strands, which is very critical. It’s similar to your tendons, which all have directionality. You can bend an arm in one direction but not in another. Spider silk has multileveled structures, or hierarchy they are not made of a single type of proteins. They are made of different proteins, which have different morphologies and orientations. And there are seven different types of glands that spiders produce to spin their silks.

Furthermore, spiders are knitting these silks into orb webs of different kinds of geometry, and that’s also enhancing the strength. If you have spider web in the wind, it can move around, but it doesn’t actually break part. Having this kind of geometry is really important. Some researchers even argue that wind induces variations in spiderweb geometry.

This is something we are trying to do right now with origami/kirigami structures: You’re not changing the material’s intrinsic property, just using cutting and folding as a tool, which brings an extra, previously unattainable level of design, dynamic, and deployability that make an initially rigid, unstretchable panel stretchable and foldable at any scale.

Spider-man’s synthetic web fluid is described as “a shear-thinning liquid” that “on contact with air, the long-chain polymer knits and forms an extremely tough, flexible fiber.” Is this a material that sounds realistic?

Absolutely. Shear thinning means it is originally a stiff or highly viscous material, but if you shear it, it becomes less viscous and can be easily aligned in the shear direction. That’s why you create a certain kind of alignment of molecules.

For example, ketchup is a shear thinning material. It’s difficult to get out of the bottle, so you shake it to shear the molecules in the ketchup, which decreases the viscosity. The biopolymer chains will stretch so they become disentangled and slip away from each other, and that’s why they can come out of the bottle.

In 3D printing, shear thinning is very important because when you print, you want the material to go through as a liquid, otherwise it will clog the nozzle. But once it comes out you want it to be solidified, immediately, otherwise the material collapses, and you won’t be able to have a good print.

One of Spider-Man’s powers is the ability to climb walls and buildings. There are a few animals in addition to spiders, such as geckos, who can also do this. How does it work?

In the field of robotics, the gecko excited people because their ability to climb walls is not based on the capillary or on the vacuum. With frogs, they have liquid coming out, so it’s kind of sticky and messy, plus you would have to carry the liquid for the robot. Likewise, if it’s based on a vacuum, you need to carry the vacuum pump, so it’s not energy efficient.

I showed this movie in my class: This guy was using vacuum pads to climb, and even though it’s just a five-level building, it takes him several hours. At the end he saw rain and he started to worry, because if you have water your vacuum doesn’t work anymore.

That’s why people are interested in the gecko because it has none of this. It’s based on the Van der Waals interaction through microscopic hairs, called setae, on their toe pads and at the end of each seta there are about 1,000 nano hairs, called spatulae. They have many, many rows of setae. When setae/spatulae are straight, there’s very little contact of them with a flat surface, so it’s very easy to come off. However, when the setae bends, the contact area increases significantly, considering there are millions of spatulae, so you have better adhesion. The setae can open and close this way, so that’s how they change the adhesion.

We can fabricate those structures that can mimic the structural adhesion, but the problem is that the gecko is only 50 grams and they have millions of these setae on their palm. It’s actually over-engineered. A human is at least 50 kilograms, so 1,000 times bigger.

For comparison, super glue adhesion is about 1,000 newtons per square centimeter strong, duct tape is 50, and the gecko setae is only about 10. So researchers face this dilemma: If you want super strong, like superglue, it’s not reversible, and if you want it reversible, you can’t go super strong.

How close are we to developing a material that will let people climb up walls without relying on a vacuum or wet, sticky adhesive that’s not reversible?

We just got a paper accepted about this adhesive. It’s super strong and reversible, and my student used 2-centimeter-square strips to hold himself up. It’s made from a hydrogel that has been used in contact lenses. As you know with a contact lens, if you put it into the water it’s soft, bendable, but if you forget to put it in water, it becomes dry and brittle or glassy. Our material is rubbery in the water and glassy when dry.

When its rubbery, you put it on a substrate, and no matter what kind of substrate it is, the material squeezes into it, and during the drying they become rigid. The beauty is that while drying they don’t shrink that much. Why is this important? On the surface there are many grooves, so the material squeezes into these grooves and makes perfect contact. However during drying, if they shrink, they delaminate, and pop out, thus, losing the contact with the substrate.

Our hydrogel material doesn’t shrink much, and it dries very fast, so it keeps the deformed shape. And within minutes the material actually changes the elastic modulus by 1,000 times, so all of a sudden it goes from squishy, squeezing into the cavity, to very rigid, like plexiglass. Importantly, it remains in the cavity, which means it’s difficult to pull them apart from the substrate. But if you add water, they swell and become rubbery and slippery, so you can separate them.

Peter Parker is known for being a superhero, but he’s also a student with a strong interest in science and engineering. Do you think Parker has characteristics that make him a good scientist as well as being a masked crusader?

The most important thing about being a scientist or an innovator is you need to have curiosity. Peter Parker was curious. He saw this spider, he was wondering what was going on, then he was bitten by it.

It’s also not afraid of taking a risk. It’s always OK to make a mistake because if you make the mistake, you learn, and you can keep trying new things.

In the meantime, I would like my students to do their homework first and anticipate the risk. I told them that before you do the experiment, give me a plan. Think about what is a potential outcome, what should I pay attention to, so your research will be more productive. If something comes out unplanned, it will be easier for you to trace back and find out why. Then it will lead to a new round of discovery and understanding.

So, if you see something different, don’t just ignore it it could be something more interesting or a breakthrough. A lot of science could go into a different direction, so being open minded and being curious is really critical.


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Identification of this spider? - Biology

One of the more colorful spiders in Florida is the spinybacked orbweaver, Gasteracantha cancriformis (Linnaeus) 1767. Although not as large as some of the other common orb weavers (e.g., Argiope, Levi 1968 Neoscona, Edwards 1984), the combination of color, shape, and web characteristics make Gasteracantha cancriformis one of the most conspicuous of spiders. The colloquial name for this spider in parts of Florida is crab spider, although it is not related to any of the families of spiders commonly called crab spiders, e.g., Thomisidoe.

Figure 1. The spinybacked orbweaver, Gasteracantha cancriformis (Linnaeus), in its web. Photograph by Andrei Sourakov, Florida Museum of Natural History.

Systematics (Back to Top)

Because of the variations in color and shape of the abdominal "spines" throughout its range, Gasteracantha cancriformis has been described by numerous early scientists under a plethora of names (Levi 1978). Although Kaston (1978) continued the use of the name Gasteracantha elipsoides (Walckenaer) 1841, resurrected by Chamberlin and Ivie (1944), Levi (1978) examined this species and found it to be a synonym of Gasteracantha cancriformis.

Distribution (Back to Top)

This species belongs to a pantropical genus which contains many species in the Old World. With the possible exception of the West Indian Gasteracantha tetracantha (L.) (which may be only a geographic race), Gasteracantha cancriformis is the only species of its genus to occur in the New World, ranging from the southern United States to northern Argentina (Levi 1978).

Identification (Back to Top)

This species can be easily distinguished from all other spiders in Florida. Females may be 5 to nearly 9 mm in length, but 10 to 13 mm wide. They have six pointed abdominal projections frequently referred to as "spines." The carapace, legs, and venter are black, with some white spots on the underside of the abdomen. The dorsum of the abdomen is, typically for Florida specimens, white with black spots and red spines. Specimens from other areas may have the abdominal dorsum yellow instead of white, may have black spines instead of red, or may be almost entirely black dorsally and ventrally. Males are much smaller than females, 2 to 3 mm long, and slightly longer than wide. Color is similar to the female, except the abdomen is gray with white spots. The large abdominal spines are lacking, although there are four or five posterior small humps (Levi 1978, Muma 1971).

Figure 2. Female spinybacked orbweaver, Gasteracantha cancriformis (Linnaeus). Photograph by University of Florida.

Biology (Back to Top)

Muma (1971) discussed the life cycle and web construction of Gasteracantha cancriformis in Florida. Although males have been found in every month except December and January (Levi 1978), they are most common in October and November. Females, which are found as adults throughout the year, are most common from October through January. Mixed-mesophytic woodlands and citrus groves are where they are most frequently found. Males hang by single threads from the females' webs prior to mating, described by Muma (1971).

Ovate egg sacs, 20 to 25 mm long by 10 to 15 mm wide, are deposited on the undersides of leaves adjacent to the female's web from October through January. The egg mass consists of 101 to 256 eggs, with a mean of 169 (based on 15 egg masses). After the eggs are laid on a white silken sheet, they are first covered with a loose, tangled mass of fine white or yellowish silk, then several strands of dark green silk are laid along the longitudinal axis of the egg mass, followed by a net-like canopy of coarse green and yellow threads. Eggs are frequently attacked by specialized predators, primarily Phalacrotophora epeirae (Brues) (Diptera: Phoridae), and occasionally Arachnophago ferruginea Gahan (Hymenoptera: Eupelmidae) (Muma and Stone 1971). Eggs take 11 to 13 days to hatch, then spend two to three days in a pink and white deutova stage before molting to the first instar.

Figure 3. Egg sac of the spinybacked orbweaver, Gasteracantha cancriformis (Linnaeus). Photograph by Lyle J. Buss, University of Florida.

After another five to seven days, the spiderlings acquire dark coloration. Spiderlings dispersed within a week later in disturbed laboratory colonies, but remained in the eggsacs an additional two to five weeks in the field. Spiderlings make tiny, inconspicious orb webs or hang from single strands. In the late summer and early fall, significant increases occur in both body and web size. The larger webs have 10 to 30 radii. The central disk where the spider rests is separated from the sticky (viscid) spirals by an open area 4 to 8 cm wide. There may be as many as 30 loops of the viscid spiral, spaced at 2 to 4 mm intervals. The catching area of the web may be 30 to 60 cm in diameter. Conspicuous tufts of silk occur on the web, primarily on the foundation lines. The function of these tufts is unknown, but one hypothesis suggests that the tufts make the webs more conspicuous to birds (Eisner and Nowicki 1983), preventing the birds from flying into and destroying the webs. The webs may be less than 1 m to more than 6 m above ground. The spiders prey on whiteflies, flies, moths, and beetles that are caught in the webs.

Figure 4. The spinybacked orbweaver, Gasteracantha cancriformis (Linnaeus), in its web. Photograph by Andrei Sourakov, Florida Museum of Natural History.

Survey and Detection (Back to Top)

Citrus workers frequently encounter this species, and it may occur on trees and shrubs around houses and nurseries. Specimens may be easily collected in small vials, and are best preserved, as are all spiders, in 70 to 80% ethyl or isopropyl alcohol.

The bite of this common species is not known to cause serious effects to humans.


Spider

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Spider, (order Araneida or Araneae), any of more than 46,700 species of arachnids that differ from insects in having eight legs rather than six and in having the body divided into two parts rather than three. The use of silk is highly developed among spiders. Spider behaviour and appearance are diverse, and the araneids outside Europe, Japan, and North America have not been thoroughly collected and studied.

All spiders are predators, feeding almost entirely on other arthropods, especially insects. Some spiders are active hunters that chase and overpower their prey. These typically have a well-developed sense of touch or sight. Other spiders instead weave silk snares, or webs, to capture prey. Webs are instinctively constructed and effectively trap flying insects. Many spiders inject venom into their prey to kill it quickly, whereas others first use silk wrappings to immobilize their victims.


“Sparklemuffin” and “Skeletorus” are two new spider species

It’s not every day that species get such awesome names – but then again, it’s not every day that such awesome spiders are discovered. Two gorgeous new species of spider have been discovered in Australia (where else?), and the researchers who made the discovery decided to give them these memorable names.

The species are a part of the jumping spider family, belonging to the peacock spider genus. They’re called peacock spiders not only because they are so brightly colored, but also due to their dancelike, courtship rituals. The two new species were found in southeast Queensland by Madeline Girard, a graduate student at the University of California, Berkeley and a friend who accompanied her in the field.

Girard affectionately nicknamed one of the spiders (Maratus jactatus) Sparklemuffin and the other one (Maratus sceletus) Skeletorus – it’s easy to understand why.

Sparklemuffin looks very similar to other known species of peacockspider, while Skeletorus, with its black-and-white coloring, looks entirely different from its genetic relatives.

“[Skeletorus] looks dramatically different [from] all other peacock spiders known to date, making me think that this group is perhaps much more diverse than we had thought,” said Jürgen Otto, an entomologist who specializes in photographing the arachnids and who co-authored the study. “Despite the large number of species we have discovered just in the last few years, I can’t help feeling that we may have just scratched the surface of this most exciting group of spiders, and that nature has quite a few more surprises in store,” Otto added.

Peacock spiders have been admired and cherished by biologists since they were discovered. Octavius Pickard-Cambridge, who is credited with the first formal biological description and hence is noted as the person assigning it its binomial name wrote in his first description that “it is difficult to describe adequately the great beauty of the colouring of this spider”.

Sparklemuffin is quite similar to other, previously discovered species, but this didn’t stop it from charming researchers.

“It was in particular its docile nature and soft teddy bearlike appearance that really charmed me,” he said. “It was a fun spider to work with.”

But they were even more excited to study Skeletorus – a spider unlike anything that’s been reported in biological studies. Needless to say, this goth guy is named after his black and white coloring the species is actually making biologists think there may be more to peacock spiders than previously believed.

“[Maratus sceletus] looks dramatically different than all other peacock spiders known to date, making me think that this group is perhaps much more diverse than we had thought. Despite the large number of species we have discovered just in the last few years, I can’t help feeling that we may have just scratched the surface of this most exciting group of spiders, and that nature has quite a few more surprises in store.”

The team was actually able to catch Skeletorus during its mating ritual.

“When [the male] got within a few centimeters of the female, he exploded into a firework of activity,” he told Live Science. “The spinnerets were extended and flicked around at an amazing speed, one of the legs was flexed like he wanted to show off his muscles, and he moved constantly from one side of the grass blade to the other.”


I guess it depends on your standards what you can call ‘cute’, but in terms of spiders, I think this is as cute as it gets.