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RE: Spiders - Tshokwane - 10-15-2017
Credits to Adam Fletcher.
Peacock spider Maratus neptunus portrait. NSW Australia.
*This image is copyright of its original author
RE: Spiders - Tshokwane - 10-21-2017
Credits to Tarantupedia.
A new species of the horned baboon spider genus Ceratogyrus has been discovered in Mozambique. In this video we show the adult female and adult male of this species.
RE: Spiders - Tshokwane - 10-21-2017
Credits to BBC Earth.
About a recently described species, Habronattus aestus.
Click on it to play.
RE: Spiders - Tshokwane - 10-21-2017
Credits to The Silk Road.
Male Eresus kollari photographed by Achim Kluck in Germany.
The Eresidae family contains 98 species in 9 genera that are mainly found in the Old World. There is just one British species, the Ladybird Spider, Eresus sandaliatus, which is only found in a few sites in Dorset. They live in sandy, sunny slopes in lowland heather, building their tubes in the ground.
The common name applies to the adult male which is indeed a stunning spider, with black legs ringed with white and a bright scarlet abdomen with six paired black spots. Females rarely leave their burrows, while males wander in the springtime in search of females. They are cribellate spiders, that is, they produce woolly silk that they brush with comb-like bristles on their rear legs and trip threads cover and surround each burrow. Ladybird spiders are highly endangered in the UK and are Protected under the Wildlife and Countryside Act 1981.
*This image is copyright of its original author
RE: Spiders - Tshokwane - 10-21-2017
Credits to Science Magazine.
Spider genes put a new spin on arachnids’ potent venoms, stunning silks, and surprising history: By Elizabeth Pennisi.
For a display of nature's diabolical inventiveness, it's hard to beat spiders. Take the reclusive ogre-faced spider, with its large fangs and bulging, oversized middle eyes. Throughout the tropics these eight-legged monsters hang from twigs, an expandable silk net stretched between their front legs so they can cast it, lightning-fast, over their victims. Showy peacock spiders, in contrast, flaunt rainbow-colored abdomens to attract mates, while their outsized eyes discern fine detail and color—the better to see both strutting mates and unsuspecting prey. Bolas spiders, named for the South American weapon made of cord and weights, specialize in mimicry. By night, the female bolas swings a silken line with a sticky ball at its end while emitting the scent of a female moth to lure and nab male moths.
Among spiders, "Every group has a weird story," says Hannah Wood, a spider researcher at the Smithsonian Institution National Museum of Natural History (NMNH) in Washington, D.C. Spiders' universal ability to make silk helps explain their global success—an estimated 90,000 species thrive on every continent except Antarctica. This material, used for capturing prey, rappelling from high places, and building egg cases and dwellings, is itself fantastically diverse, its makeup varying from species to species. The same goes for venom, another universal spider attribute—each species makes a different concoction of up to 1000 different compounds.
Until recently, arachnologists trying to unravel how spiders' vast range of adaptations arose built family trees based on morphology and behavior. Lately, however, studies of genes and proteins are opening a new era of spider biology. Researchers have sequenced full genomes of three species—the golden orb-weaver, the African social velvet spider, and the common house spider—and have done more limited genetic and protein studies on many others. The analyses are highlighting the tangled paths of spider evolution, bringing into focus the complexities of spider silk and venom, and suggesting molecular-based ways to study these animals' behaviors. "Genomics has impacted nearly everything," says Jason Bond, who studies spiders at Auburn University in Alabama. "It's changed the kinds of questions people can ask."
Based mainly on fossil evidence and specimens preserved in amber, biologists concluded long ago that spiders descended from a many-legged, scorpionlike ancestor that by 380 million years ago had a long tail but looked quite spiderlike and may even have had silk glands. By 300 million years ago, fossils show, eight-legged creatures with spiderlike mouth parts, primitive silk glands, and stumpy abdomens had emerged. Those abdomens were still segmented, not fused as in today's spiders. But what happened afterward to produce the explosion of spider diversity seen now has been mysterious.
Within those three groups, researchers have tried to classify species by the direction of their fangs, the shape of their sexual parts, and other aspects of their appearance or behavior. They also enlisted molecular methods beginning in the early 1990s, when arachnologists identified a half-dozen short, conserved spider DNA sequences that still had enough variation between species to derive relationships. Yet those analyses "never really worked that well," says NMNH evolutionary biologist Jonathan Coddington. Now, more powerful genomic tools are beginning to make sense of the tangle. "After years of effort, all of a sudden pretty reasonable [family trees] are coming out," says Linda Rayor, a behavioral ecologist at Cornell University.
A milestone came in 2014, when two reports in Current Biology "turned spider evolution upside down," says Gustavo Hormiga, a spider systematist at The George Washington University in Washington, D.C., who co-led one of the studies. Instead of using the usual small set of DNA markers, both teams compared hundreds of genes from up to 40 spider species to build a family tree that included all the web builders. Contrary to earlier studies, the analyses divided orb weavers, the many spider species that make the classic spiral webs and cobwebs, into two groupings and put them on very different branches of the tree. Orb weavers that produce fuzzy, sticky fibers called cribellate silk ended up in a part of the tree that includes many spiders that don't make webs at all, whereas orb weavers that make a woolly silk are on their own branch.
That unexpected breakup has two possible explanations. Either the behaviors, body structures, and materials used in weaving webs evolved twice, or web capabilities evolved much earlier in a common ancestor of both branches and were lost in many species on the cribellate web weavers' branch. Bond, who led the other study, thinks it is more likely that orb weaving evolved only once, in a common ancestor.
In a later study comparing almost 3400 active genes in 70 spider species, Bond's team found that mostly webless, ground-dwelling arachnids such as wolf spiders and jumping spiders diversified much more quickly than web weavers, perhaps because they were able to exploit a plethora of new opportunities once they no longer had to build and tend webs. "Once we get rid of the orb web, that's where we see some of the biggest bursts of speciation," Bond says.
This diversification occurred about 100 million years ago, he and his colleagues reported 16 February 2016 in PeerJ, around the same time as an explosion of nonflying insects that could serve as prey for ground-based spiders. Such genetic comparisons, Bond says, "are transforming our understanding of spider evolution."
Spider biologists expect to learn still more from complete genomes. But spider genomes "have been a hard nut to crack," says Jessica Garb, an evolutionary biologist and geneticist at the University of Massachusetts in Lowell. The genomes are big—some surpass the human genome—and full of repetitive DNA. Moreover, spiders are not closely related to most of the other animals whose genomes have already been sequenced, making it difficult to use those references to piece together and analyze spider genomes. And overall, there's never been a lot of funding available for spider research. Whereas for some animal groups—such as birds—hundreds of genomes have been sequenced, only four spider genomes have been even partially deciphered.
Called ogre-faced spiders because of their looks, these gangly arachnids are also known as net-casting spiders for their hunting technique. EMANUELE BIGGI/MINDEN PICTURES.
*This image is copyright of its original author
Evolutionary biologist Trine Bilde at Aarhus University in Denmark spearheaded the first genome project as part of her research into the boom and bust lives of the African social velvet spider, Stegodyphus mimosarum. This species lives in nests, with up to 1000 individuals, mostly females, spinning dense, meter-sized webs capable of snaring 15-centimeter-long grasshoppers. The spiders are homebodies and therefore tend to breed only within their colony. That habit, plus evidence that colonies sometimes die out very quickly, suggested that they might be highly inbred, lacking the genetic variation that shields other organisms against such die-offs. Yet the species also thrives in a wide range of temperatures and humidity.
Bilde thought the velvet spider's genome would hold clues to the animal's social behavior and its odd mix of resilience and fragility, so her team and the Chinese sequencing giant BGI set out to sequence its DNA and, for comparison, that of a tarantula. The researchers expected that inbreeding—which reduces genetic variation between individuals—would make the social velvet spider's genome easier to complete. To their surprise and dismay, the genome turned out to contain long stretches of noncoding and repetitive DNA, which made it difficult to piece together the short reads produced by the sequencing machine. The tarantula genome was even worse—twice as large and even richer in duplicated regions. Drawing on significant computer power, however, they were finally able to stitch together the social velvet spider's genome, although they could not assemble a satisfying version of the tarantula's.
These genomes are only starting to be plumbed for insight on the velvet spider's social behavior and its adaptability. Bilde's team also plans to study populations of velvet spiders living in different environments to check whether changes in their microbiome or so-called epigenetic changes—chemical modifications of DNA—help the animals cope with varied and changing conditions.
Meanwhile, these first genomes—together with less ambitious molecular studies—are yielding a different payoff: They are helping break open silk and venom research. Cheryl Hayashi, a spider silk geneticist at the American Museum of Natural History in New York City, is among the researchers thrilled by what she is learning about the molecular diversity of these substances. "I feel like I am so fortunate to be working at this time," she says.
When the labyrinth spider senses vibrations, it rushes out to catch prey and then retreats into its homespun tunnel. ALEX HYDE/MINDEN PICTURES
*This image is copyright of its original author
Silk genes, which code for extremely large proteins with stretches of amino acids that repeat many times, are themselves long and full of repetitive DNA that's hard to decipher. But the velvet spider genome, together with that of the orb weaver and the house spider, has exposed an unexpected variety of silk genes—"a lot more than we thought," Coddington says. Researchers had already identified two genes for the class of silk known as major ampullate, which forms the superstrong dragline threads that anchor webs and are the inspiration for a major effort to make spider silk commercially (see p. 293). The social velvet spider's genome, however, revealed 10 genes just for that one kind of silk and nine other genes for additional silk proteins.
In search of more, Hayashi embarked on one of the other genome efforts. Early in her career, she had cloned the Flag gene, which codes for flagelliform silk, the elastic filament that orb weavers use in the insect-capturing spirals of their webs. The task took many months and was "not for the faint of heart," Hayashi recalls. So she was happy to join with Benjamin Voight from the University of Pennsylvania, Ingi Agnarsson from the University of Vermont in Burlington, and others to decipher and characterize the genome of the golden orb-weaver (Nephila clavipes).
The genome, the group reported online on 1 May in Nature Genetics, contains 28 silk genes, eight of them new to science. "In the past, we thought we could define all the silk genes in one species, that there would be a handful, and we could say, ‘This is the gene for a particular kind of silk,'" Hayashi says. "But it turns out that it's not that simple." Not only is there no one-to-one correlation between genes and silk types, but some silk genes seem to have gained entirely different functions. One of the orb weaver's silk genes is even expressed in the spider's venom gland.
Hayashi and her colleagues are now building on the genetic studies to learn how spiders make their silk. The typical orb weaving spider has many silk glands divided into seven types; each type of gland produces a specific mixture of proteins, which forms a distinctive type of silk when it is extruded through one of the spider's spinnerets. Hayashi and her colleagues have recently identified which silk genes are active in each of the golden orb-weaver's seven types of glands. They have also looked for the activity of similar genes in the silk glands and other tissues of cobweb-weaving spiders, a subset of orb weavers that build 3D webs instead of flat ones. They discovered 209 potential silk and glue components, the team reported on 21 August in Scientific Reports. "It's mind boggling," Hayashi says.
The newly deciphered genes help explain the molecular basis of spider silk properties. The silk genes contain short stretches of DNA called motifs that vary between species in number and in their exact sequence. By comparing the genetic differences with differences in silk properties, Hayashi's team has found that those motifs appear to influence strength, elasticity, and other features.
Sorting out this complexity may help bioengineers better understand and, ultimately, harness silk's remarkable strength and flexibility. "In these sequences, there are answers to questions such as, ‘How do spiders keep the silk liquid at extremely high concentrations in the body?’" Hayashi notes. "It's hard for biochemists to do this." For example, she and others found that the silk glands contain nonsilk proteins that may serve as molecular chaperones to help with production of the fiber.
For researchers trying to make artificial silks, these findings are a gold mine. "All of a sudden we can do molecular genetics of silk," Coddington says. "The door is open."
The door has also flown open for the similarly complex world of spider venoms, which may offer compounds useful for controlling insects or relieving pain. "Venom cocktails are really rich; they can have up to 1000 different chemicals and the mix varies a lot," says Greta Binford, an evolutionary biologist at Lewis & Clark College in Portland, Oregon, who studies the unusual tissue-destroying properties of the venom of the brown recluse spider. (People who are bitten can develop gangrene so serious they can lose a limb.) The new genomes and follow-up protein studies, she notes, "give us more confidence that we're capturing a comprehensive set of venoms."
Australia's tiny peacock spiders wiggle their colorful abdomens to attract mates. ADAM FLETCHER/MINDEN PICTURES
*This image is copyright of its original author
Even before the recent genome work, researchers had characterized some of the components of black widow venom, identifying two seemingly unique families of proteins: latrotoxins, which act on neurons; and latrodectins, whose role in venom remains unclear. (Both are named for the black widow genus, Latrodectus.) The black widow genome likely contains genes for many more toxins, but it has proven exceptionally hard to piece all of its DNA sequences together. So she and her colleagues have instead looked for venom genes in the genome of a close Latrodectus relative, the common house spider, Parasteatoda tepidariorum, which was reported on 31 July in BMC Biology by a team headed by Alistair McGregor of Oxford Brookes University in the United Kingdom.
Although a house spider's bite is not as painful as the black widow's, Garb and her colleagues were surprised to find that its venom is seething with latrotoxins—47 in all, they revealed on 16 February in BMC Genomics. All differ from those known in black widow venom. The finding "suggests [that spider family] is evolving in a very dynamic way," Garb says. For example, black widows make α-latrotoxin, which specifically attacks vertebrate nerve cells, but the house spider does not. This toxin may have evolved in black widows because they are big enough to build webs capable of ensnaring small lizards and other prey with backbones, Garb suggests.
The analysis also supports the provocative idea that members of Latrodectus got their neurotoxins when a bacterium invaded their ancestor's cells and left behind some of its DNA. Combing through a genome database revealed that the closest known matches to the house spider's latrotoxin genes are bacterial genes. "Understanding the dynamics of venom evolution will help us refine not only our searches for new drugs and therapies, but also our understanding of how evolution generates chemical novelties," Binford says.
Among spiders, silk and venom stand out as two key chemical novelties. But spiders have other impressive and unique adaptations. Peacock spiders and other jumping spiders use internal hydraulic pumps rather than leg muscles to leap 30 times their body length. Spitting spiders spew silky glue from their venom glands to pin down other, larger spiders for a killing bite to the leg. African sand spiders can survive a year with no food or water.
The size and complexity of spider genomes means that new sequences, and revelations about such traits, will be slow in coming. But like the patient predators they study, spider researchers are willing to wait. The rewards of genomics will come in time, they say. "Spider systematics, spider evolution and ecology, even spider behavior, have lagged for many years because [of ] the genomic complexities," Bond says. "That's changed. Arachnology is starting to reach a level of maturity."
RE: Spiders - Tshokwane - 10-21-2017
Credits to The Silk Road.
Myrmarachne sp. Photographed by Peter Grob in Wiaenkaen, Chiangrai Thailand.
The genus name is a combination of Ancient Greek, myrmex "ant" and arachne "spider".
*This image is copyright of its original author
RE: Spiders - Tshokwane - 10-22-2017
Credits to Science Magazin.
*This image is copyright of its original author
RE: Spiders - Tshokwane - 10-25-2017
Credits to Tim Miller.
Holconia sp., Sparassidae
Brisbane, Australia.
*This image is copyright of its original author
*This image is copyright of its original author
RE: Spiders - Tshokwane - 11-08-2017
Credits to Faiz Bustamante.
Managed to get the shots minutes before the rain started pouring. We were all drenched by the time we left the forest.
Portia labiata with her precious eggs. She reminds me of a Silky Terrier.
*This image is copyright of its original author
RE: Spiders - Tshokwane - 11-26-2017
Credits to Husni Che Ngah.
Cork-lid Trapdoor Spider
Ctenizidae - Latouchia sp. Pocock, 1901 (?)
*This image is copyright of its original author
RE: Spiders - Tshokwane - 12-06-2017
Tiny Spider Gobbles Tadpole in Never-Before-Seen Behavior by Stephanie Pappas.
Forget meals of flies and gnats; those are for amateurs. One jumping spider in India is feasting on tadpoles instead.
Credit: Sagar Satpute
*This image is copyright of its original author
For the first time, researchers have observed a jumping spider preying on a tadpole. The scientists stumbled across the strange scene in the Kumbharli Ghat mountain pass of western India.
Late one afternoon in 2014, during monsoon season, researchers doing a botanical survey noticed a 7-foot (2.1 meters) cliff with streamlets cascading down it. Several tadpoles were clinging to the muddy rock within the flowing water. And stalking them was a small, brown-and-black spider with fuzzy white fur on its foremost appendages. As the researchers watched, the spider snatched one of the tadpoles from midstream and dragged it up the cliff to consume it.
"We realized at once that this was completely new, undocumented behavior," said Javed Ahmed, an arachnologist on the research team and the co-author of a new paper in the journal Peckhamia describing the discovery.
Jumping spiders
Jumping spiders are a large group of species known for their active hunting style. Instead of weaving webs, these arachnids typically pounce on prey. They likely have the best vision of any land-dwelling invertebrate, Ahmed told Live Science in an email. (This fact was made semifamous in a much-beloved Twitter thread in which a University of Washington astronomer facing a jumping spider infestation in her office discovered that the arachnids would chase a laser-pointer light. The astronomer ended up in a lively conversation with a University of Cincinnati expert on jumping-spider vision who subsequently calculated that the spiders' eyes are sharp enough to see the moon.)
Some large species of jumping spider have been known to prey on small amphibians, Ahmed said. A recent study in the Journal of Arachnology, for example, reported that the species Phidippus regius, found in Florida, can sometimes prey on frogs and lizards. That species grows to be about 0.8 inches (2.2 centimeters) long, however, much larger than most jumping spider species.
Jumping spiders "are not the spiders which come to mind when one's talking about spiders which can take aquatic vertebrates, such as small fish and tadpoles," Ahmed said.
Biodiversity hotspot
The spider that Ahmed and his colleagues observed was likely a close relative of the common species Hasarius adansoni, based on its markings and size, the researchers reported. They couldn't identify it more specifically; it could be a previously undiscovered species, Ahmed said. At any rate, H. adansoni grows to only about 0.3 inches (8 millimeters) in length, much smaller than the amphibian-hunting Florida species.
The Western Ghats, where the spider was seen, are a chain of mountains chock-full of unexplored biodiversity, Ahmed said. He tweets about his work in the area (and about other invertebrate research) @curiocritters. Ultimately, he said, the goal of this research is to fill in the huge gaps in what is known about biodiversity in the Western Ghats.
"[The] species richness, coupled with a lack of proper research on many groups of invertebrates in the region, means there are several organisms waiting to be discovered, or rediscovered," he said. "And that's just what we're doing, discovering spiders one species at a time."
RE: Spiders - Tshokwane - 12-17-2017
Credits to Husni Che Ngah.
Oxyopidae - Hamataliwa sp. Keyserling, 1887.
*This image is copyright of its original author
RE: Spiders - Tshokwane - 12-17-2017
Credits to Gil Wizen.
Little Transformers: Myrmarachne formicaria:
Little Transformers is back! And this time our star is a small jumping spider that goes out of its way to masquerade as an ant.
I am often accused for not writing about topics related to Canada on this blog. While this is not entirely true, I could have without doubt posted more about local critters. It is a great time to do so now, as I will be taking the opportunity to address several events.
Firstly, it is now October, and we are getting closer and closer to Halloween (Oct 31st). Nine years ago, the Arachtober initiative was born: why wait till the end of the month to celebrate spiders? Let’s celebrate them and other arachnids throughout the entire month of October! And so, during the month of October we give arachnids more exposure in hopes to educate the general public about these magnificent and important creatures.
Secondly, a new initiative is slowly forming, International Jumping Spider Day, on October 10th. The idea is to use the easily adored jumping spiders as the gateway arachnid for changing the often-negative public perception of spiders. I wholeheartedly support this idea and hope to see it catching on.
Lastly, a shameless plug: You may have noticed that this blog is nominated for the 2017 People’s Choice Awards: Canada’s Favourite Science Online. It is a huge honor to be included with other excellent science blogs and sites on the same list. If you like the content and stories that I post, you can show your appreciation by voting following this link. I wish to thank those who already voted in support of this blog. While this nomination has nothing to do with spiders, I thought it is a great opportunity to write a blog post about an arthropod found in Canada.
Female ant-mimicking jumping spider (Myrmarachne formicaria)
*This image is copyright of its original author
After this short introduction, it is time to present our first local Little Transformer, the ant-mimicking jumping spider Myrmarachne formicaria. It is one of the nicest looking spiders here in Ontario, and it is surprisingly abundant in its habitat. Alas, there is a small catch here. While this jumping spider is local, it is not native to Canada. This species was first detected in North America in 2001, and later established in Tommy Thompson Park in Toronto in 2015. It originates in the Palearctic region, more specifically Europe and Asia. Despite this, these spiders feel right at home in Toronto, as it seems that they are spreading away from the park containing the main population. This year, Sean McCann recorded Myrmarachne in Scarborough (east Toronto), and I found them in Mississauga (west of Toronto).
Female ant-mimicking jumping spider (Myrmarachne formicaria) masquerading as an ant
*This image is copyright of its original author
Myrmarachne formicaria is an elongated jumping spider that takes the appearance of a small ant, and here in Ontario it is associated with the European fire ant, Myrmica rubra, also an introduced species. Isn’t it interesting how these two non-native species managed to find each other on unfamiliar land? The spider has long and slender legs just like those of an ant, and the banded forelegs are slightly thicker to resemble antennae. The cephalothorax has a depression to echo the segmentation in ants separating head from thorax. The abdomen is long with a narrow connection to the cephalothorax, reminiscent of an ant’s petiole. Surprisingly, in this species the pedipalps (normally a distinguishing character between males and females) are swollen in females, a trait usually seen only in males. Males on the other hand have enormous toothed chelicerae that stick right out of their faces. I suspected this is a sexually selected trait used in fights for females, and this was later confirmed by Sean McCann (check out his amazing shots here).
Female ant-mimicking jumping spiders (Myrmarachne formicaria) have swollen pedipalps
*This image is copyright of its original author
Male duck-mimicking jumping spide… um, excuse me ANT-mimicking jumping spider. Quack quack.
*This image is copyright of its original author
This begs the question, why do Myrmarachne spiders look like ants? Do the spiders use their appearance to fool the ants into thinking they are members of their own colony in order to sneak up on them and prey on ant workers or larvae? Not really. For starters, the ant species approached by Myrmarachne formicaria are usually not visual creatures. They rely more on their chemical communication, using volatile pheromones, for navigation and recognition. Moreover, the spiders seem to deliberately avoid any contact with the ant workers. They may walk among the ants, but they always keep their distance from them. In fact, when I experimented and isolated a few spiders within a group of ants, the spiders chose to stay still, and only when the path was clear they made a run for it. I also noticed that the ants display an aggressive response when encountering a spider. So the ants are not the target of this mimicry. Who is? Us. Or more precisely, predators. You see, the spider not only looks like an ant and spend its time close to the ants, it also moves like an ant.
Myrmarachne formicaria always keep a safe distance from Myrmica rubra workers
*This image is copyright of its original author
A recent study looked into the locomotion of Myrmarachne formicaria jumping spiders and found that they do not move like their peers. First of all, instead of jumping like most salticid spiders, they move forward in a series of short sprints. But they also move in a pattern that resembles the movement of ants following a pheromone trail, back and forth in a winding wave motion, instead of random strolling and stopping often we see in other spiders. If it looks like an ant and moves like an ant… it might be good enough to fool predators that it is an ant. And I can attest to this – it is extremely difficult to keep track of a Myrmarachne spider moving about in an area with ant activity. Look away, and you will need all the luck in the world to find it again. The spiders also benefit from being close to a colony of highly defensive ants. Myrmica rubra is easily alarmed and has its reputation when it comes to stinging intruders.
Some Myrmarachne formicaria feature a two-colored cephalothorax, to emphasize the part that mimics the ant’s head
*This image is copyright of its original author
If they do not hunt the ants, what do these spiders feed on? They seem to go after soft-bodied insects, and they are especially fond of dipterans: small flies, mosquitoes, midges etc’.
Male ant-mimicking jumping spider (Myrmarachne formicaria) feeding on a chironomid midge
*This image is copyright of its original author
A closer look at the feeding Myrmarachne male reveals the weaponized chelicerae, used in fighting other males
*This image is copyright of its original author
At this point you might ask yourself why I included this jumping spider in my Little Transformers series. Sure, it mimics an ant, but that’s it. Or is it? In order to qualify as a Little Transformer the arthropod needs to change something in its appearance to transform into something different. So far we have seen that these spiders move in an atypical fashion to jumping spiders. But there is one more thing they do to conceal their salticid identity. What is the one, fail-safe characteristic of jumping spiders? Those huge front eyes! If only the spider could hide them, it would look like the perfect ant. And they do exactly that.
I look at this spider and I see an ant staring back at me.
*This image is copyright of its original author
Myrmarachne often wave their forelegs in the air to mimic the ants’ antennae, but the legs also hide their most recognizable feature, the bulging front eyes. Females seem to do a better job at this than males, transforming into ants right before our eyes.
Male ant-mimicking jumping spider (Myrmarachne formicaria). Even on a side-view I still see a weird duck…
*This image is copyright of its original author
What is most intriguing here is that the rear pair of eyes evolved to be very large, bearing a striking resemblance in their size and position to ant eyes.
Ant-mimicry is quite common among arthropds, and many species of jumping spiders deploy this strategy as an anti-predator defense or to assist in foraging. While some do not consider Myrmarachne formicaria as a case of perfect mimicry, it is a gorgeous spider with intriguing behavior. Besides, mimicry does not have to be perfect to satisfy our aesthetic desires. It only has to be good enough to benefit the spider’s survival.
RE: Spiders - Tshokwane - 12-18-2017
Credits to Alan Henderson.
Courage: A male Golden Orb-weaver (Nephila pilipes) on the back of an enormous female. A wrong move will end in tears -he's already lost three legs!
*This image is copyright of its original author
RE: Spiders - Spalea - 12-19-2017
@Tshokwane :
About #59: incredible... More than if a man copulates with an heavy sized-dinosaur woman (in proportion).