Prehistoric harvestman had extra eyes


This video says about itself:

10 April 2014

A 305-million-year-old harvestman fossil, ancestor of modern day arachnids, is more closely relates to the scorpions than spiders. Scientists discovered unusual features: it has 2 sets of eyes on the center and lateral sides of the body.

From Discovery News:

Ancient Daddy Longlegs Had Extra Eyes

APRIL 12, 2014 12:30 PM ET // BY PAUL HELTZEL

A 304-million-year-old fossil discovered in Eastern France shows primitive living harvestmen — more commonly called daddy longlegs — had one more pair of eyes than they do today.

The ancient harvestmen had a pair of eyes along the middle of the body — like their modern counterparts — but they also had a pair of eyes on the side of the body. The findings were reported by researchers from the American Museum of Natural History and the University of Manchester, in the journal Current Biology.

Photos: Look If You Dare: Ancient Spider Family Album

Scientists studied the fossil using high-resolution X-ray imaging at the Natural History Museum, London.

“Our X-ray techniques have allowed us to reveal this fossil in more detail than we would have dreamed possible two decades ago,” said Russell Garwood, a research fellow at the University of Manchester and a lead author on the study, in a release.

Though Harvestmen have eight legs and are categorized as arachnids, they’re not spiders. They’re more closely related to scorpions.

The scientists also examined the expression of an eye-stalk growing gene in harvestmen embryos. The embryos briefly express the gene for the second pair of eyes. But by the time they hatch, the daddy long legs’ second pair of eyes are long gone.

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Costa Rican frogs and spiders


Green-and-black poison frog, 17 March 2014

After yesterday, in the morning of 17 March 2014, still near the Sarapiqui river in Costa Rica. One of many animals there is this green-and-black poison dart frog.

Red-eyed tree frog, 17 March 2014

While a red-eyed tree frog was asleep under a leaf.

Masked tree frog, 17 March 2014

There was a masked tree frog as well.

Golden silk spider, female, 17 March 2017

In a big web, a golden silk spider couple.

Golden silk spider female, 17 March 2017

The female was much bigger than the male.

Golden silk spider male, 17 March 2017

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New spider species discovery in Malaysian Borneo


This video is called Giant spider in Kuching, Sarawak, Borneo, Malaysia at the Cultural Village.

However, there are also much smaller spiders in Malaysian Borneo.

From Naturalis Biodiversity Center in the Netherlands:

Students on field course bag new spider species

Posted on 07-03-2014 by Menno Schilthuizen

Naturalis Biodiversity Center, Danau Girang Field Centre, Sabah Wildlife Department, Pensoft Publishers

As a spin-off (pun intended) of their Tropical Biodiversity course in Malaysian Borneo, a team of biology students discover a new spider species, build a makeshift taxonomy lab, write a joint publication and send it off to a major taxonomic journal.

Discovering a new spider species was not what she had anticipated when she signed up for her field course in Tropical Biodiversity, says Elisa Panjang, a Malaysian master’s student from Universiti Malaysia Sabah. She is one of twenty students following the course, organised by Naturalis Biodiversity Center in The Netherlands, and held in the Danau Girang Field Centre in Sabah, Malaysian Borneo. The aim of the one-month course, say organisers Vincent Merckx and Menno Schilthuizen, is to teach the students about how the rich tapestry of the tropical lowland rainforest’s ecosystem is woven.

Besides charismatic species, such as the orang-utans that the students encounter every day in the forest, the tropical ecosystem consists of scores of unseen organisms, and the course focus is on these “small things that run the world”—such as the tiny orb-weaving spiders of the tongue-twistingly named family Symphytognathidae. These one-millimetre-long spiders build tiny webs that they suspend between dead leaves on the forest floor. “When we started putting our noses to the ground we saw them everywhere,” says Danish student Jennie Burmester enthusiastically. What they weren’t prepared for was that the webs turned out to be the work of an unknown species, as spider specialist Jeremy Miller, an instructor on the course, quickly confirmed.

The students then decided to make the official naming and description of the species a course project. They rigged the field centre’s microscopes with smartphones to produce images of the tiny spider’s even tinier genitals (using cooking oil from the station’s kitchen to make them more translucent), dusted the spider’s webs with puffs of corn flour (also from the kitchen) to make them stand out and described the way they were built. They also put a spider in alcohol as “holotype”, the obligatory reference specimen for the naming of any new species—which is to be stored in the collection of Universiti Malaysia Sabah. Finally, a dinner-time discussion yielded a name for this latest addition to the tree of life: Crassignatha danaugirangensis, after the field centre’s idyllic setting at the Danau Girang oxbow lake.

All data and images were then compiled into a scientific paper, which, via the station’s satellite link, was submitted to the Biodiversity Data Journal, a leading online journal for quick dissemination of new biodiversity data, which is currently considering it for publication. Even though thousands of similarly-sized spider species still await discovery, Miller thinks the publication is an important one. “It means we provide a quick anchor point for further work on this species; the naming of a species is the only way to make sure we’re all singing from the same score,” he says.

Field station director Benoît Goossens adds: “This tiny new spider is a nice counterpoint to the large-mammal work we’re doing and having it named after the field centre is extremely cool”. The Danau Girang Field Centre is located in the Lower Kinabatangan Wildlife Sanctuary, a strip of rainforest along Sabah’s major river, squeezed in by vast oil palm plantations on either side. Despite intensive search, the students could not find the new spider in the plantations.

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Spider vegetarianism, new research


This video is called Male nursery web spider (Pisaura mirabilis) offering prey to female.

From the University of Exeter in England:

Spiders partial to a side order of pollen with their flies

Spiders may not be the pure predators we generally believe, after a study found that some make up a quarter of their diet by eating pollen.

Dr Dirk Sanders of the University of Exeter demonstrated that orb web spiders – like the common garden variety – choose to eat pollen even when insects are available.

Spider webs snare insect prey, but can also trap aerial plankton like pollen and fungal spores.

Dr Sanders, alongside Mr Benjamin Eggs from the University of Bern, conducted feeding experiments and a stable isotope analysis on juvenile spiders to see whether they incorporate plant resources into their diet.

They discovered that 25 per cent of the spiders’ food intake was made up of pollen, with the remaining 75 per cent consisting of flying insects.

The spiders that ate both pollen and flies gained optimal nourishment, with all essential nutrients delivered by the combination.

Dr Sanders, of the Centre for Ecology and Conservation at the University of Exeter’s Penryn Campus, said: “Most people and researchers think of spiders as pure carnivores, but in this family of orb web spiders that is not the case. We have demonstrated that the spiders feed on pollen caught in their webs, even if they have additional food, and that it forms an important part of their nourishment.

“The proportion of pollen in the spiders’ diet in the wild was high, so we need to classify them as omnivores rather than carnivores.”

Orb web spiders regularly take down and eat their webs to recycle the silk proteins, and it had been suggested they may ‘accidentally’ consume the pollen during this process.

But the study found this to be impossible due to the size of the grains ingested, indicating that they were actively consumed by the spider coating them in a digestive enzyme before sucking up the nutrients.

The research paper, Herbivory in Spiders: The Importance of Pollen for Orb-Weavers, is published in the journal PLOS One.

Date: 18 December 2013

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Tobacco hornworm uses nicotine against spiders


This video says about itself:

The Power Of A Caterpillar’s Bad Breath (PNAS, Kumar et al)

30 Dec 2013

A spider backs off after a caterpillar unleashes its secret weapon: a breath heavy with nicotine.

Supporting material for Kumar et al., “Natural history-driven, plant-mediated RNAi-based study reveals CYP6B46′s role in a nicotine-mediated antipredator herbivore defense.” PNAS published 30 December 2013.

From Nature World News:

‘Nicotine Breath’ Helps Tobacco-Eating Caterpillar Escape Predators [ Video]

By Affirunisa Kankudti

Dec 31, 2013 08:44 AM EST

The tobacco hornworm or Manduca sexta chases away its predators by its nasty nicotine breath, a new study has revealed. The bug uses a nifty trick to convert some of its food into a cloud of poisonous compound that repels its enemies.

Nicotine isn’t just an addictive compound that’s found in tobacco-containing products. The compound is also used as an active ingredient in insecticides. In fact, nicotine is a potent neurotoxin  and can even kill people.

The tobacco hornworm is also known as the goliath worm. This species of hornworm not only tolerates high levels of the compound, but also uses it as a defense mechanism to avoid predators.

The present study was conducted by researchers at Max Planck Institute for Chemical Ecology in Germany.

“It’s really a story about how an insect that eats a plant co-opts the plant for its own defense,” study researcher Ian Baldwin, a professor at the Institute told LiveScience.

Researchers knew that caterpillars that feed extensively on nicotine containing plants are usually avoided by ants and wasps. However, no one knew why this happened.

Also, an earlier research had shown that tobacco hornworms grown on plants that don’t produce much nicotine have lower activity of CYP6B46 gene. This study had pointed to the role of genes in helping the bug neutralize the ill-effects of nicotine.

For the present study, researchers altered some genes in the plants to disrupt caterpillars’ ability to detect the compound in its food, Smithsonian reported. The changes in the plant gene resulted in silencing a corresponding gene in the caterpillar. These modified plants were then grown in a private ranch in Utah. The experts then observed how this change in diet affected the bugs’ survival technique.

The team found that hornworms that fed on these genetically modified tobacco plants were more likely to be preyed on by wolf spiders.

The conclusion was an obvious one- the absence of the gene meant that the bugs weren’t able to neutralize the effects of nicotine. However, the team didn’t find any traces of the compound in the hornworms’ feces. Instead, researchers found that CYP6B46 was helping the bug use some of the nicotine and send it to haemolymph. From there, the nicotine was sent to small pores on the caterpillar’s flanks known as spiracles. These pores release small amount of nicotine, creating a nicotine cloud around the bug, the National Geographic reported.

The study is published in the journal Proceedings of the National Academy of Sciences.

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Sheet web spider European spider of the year 2014


Linyphia triangularis, female

The sheet web spider (Linyphia triangularis) will be the European spider of the year 2014.

This species is rather common in northern Europe; less so in the south.

Biggest fossil spider, new discoveries


The largest known fossil spiders (left: male, right: female) belong to a newly described species of extinct arachnids, Mongolarachne jurassica. Credit: Paul Selden

From LiveScience:

Biggest Spider Fossil Now Has a Mate — But It’s Complicated

By Megan Gannon, News Editor

December 16, 2013 02:44pm ET

A few years ago, scientists uncovered the largest-ever fossil of [a] spider: a female representative of a never-before-seen species that was buried in volcanic ash during the age of the dinosaurs.

Now the researchers say they have found an adult male spider to match, but the discovery complicates the original interpretation of the species. The scientists have proposed a new genus — Mongolarachne — to describe the extinct creature.

When researchers first found the female spider in northern China, they named it Nephila jurassica, putting it in the Nephila genus of golden silk orb-weavers, which still exist today and have been known to ensnare birds and bats in their huge wheel-shaped webs. [Ewww! See Photos of Bat-Eating Spiders in Action]

“It was so much like the modern golden orb weaver,” said Paul Selden, a paleontologist with the University of Kansas. “We couldn’t find any reason not to put it in the same genus of the modern ones.”

With soft, squishy bodies, spiders don’t typically turn up in the fossil record, but several hundred have been found in the volcanic deposits at the Daohugou fossil beds in Inner Mongolia, Selden said.

Volcanic ash is famous for preserving more ephemeral pieces of the past, from bodies buried in their death poses at Pompeii to 2.7-billion-year-old raindrop impressions found in South Africa. Researchers think these spiders were likely swept to the bottom of a sub-tropical lake and covered in fine ash after a volcano blew its lid.

Unlike insects, spiders are typically pretty good at staying away from water, Selden explained.

“It would take something like a volcanic eruption to blow them into the bottom of the lake and bury them,” Selden told LiveScience. “That’s the sort of scenario we imagine.”

And in that volcanic rock layer at Daohugou, the researchers found another spider that looked remarkably similar to Nephila jurassica, except it was male. There were several clues in the newfound fossil, however, that suggest this ancient arachnid just doesn’t fit the bill for Nephila.

First of all, the male was remarkably quite similar in size to the female, with a body that measures 0.65 inches (1.65 centimeters) long and a first leg stretching 2.29 inches (5.82 cm).

“This is rather strange,” Selden said. “In the modern orb weavers, there is quite a lot of sexual dimorphism,” with a huge female and a tiny male.

Compared with Nephila male spiders, this newfound fossilized male had more primitive-looking pedipalps — the sex appendages between a spider’s jaws and first legs that it uses to transfer sperm to the female. And it had a more feathery hairstyle: The fossil was preserved so well that Selden could look at imprints of the spider’s hair under an electron microscope. Instead of one or two scales along each bristle, Selsen said he saw evidence that this spider had “spirals of hairlets” along the strands covering its body.

The researchers think the fossilized spiders may actually be more closely related to spiders in the Deinopoidea genus, also called ogre-faced spiders. Arachnids in this group are considered orbicularians. They also make orb-shaped webs, but their silk is more “woolly,” Selden said, with a stickiness that’s more like Velcro than glue.

Revising their original labeling of the giant fossilized female spider, the researchers created a new genus and species name for the pair: Mongolarachne jurassica. Selden and colleagues also created a branch for Mongolarachne on a phylogenic tree, placing it quite close to the stem where orbicularians originate.

The study was published online Dec. 7 in the journal Naturwissenschaften.

Follow Megan Gannon on Twitter and Google+. Follow us @livescienceFacebook Google+. Original article on LiveScience.

Editor’s Recommendations

Some entomologists fear spiders


This video is called National Geographic – Super Spider.

From Scientific American:

Spiders Bug Insect Researchers, Too

Even entomologists can’t stomach some creepy-crawlies

By Rachel Nuwer

December 3, 2013

Retired entomologist Rick Vetter understands that not everyone shares his passion for spiders. But he was surprised to learn that even some of his colleagues, who willingly study six-legged insects, abhor eight-legged arachnids.

Vetter first noticed the spider antipathy during his career at the University of California, Riverside, where his colleagues sometimes recoiled in horror at his brown recluses and black widows.

Intrigued, Vetter arranged a survey of 41 spider-fearing entomologists. Most of their aversions qualified as a mild dislike, but some ranked as full-blown, debilitating arachnophobia, Vetter reported in American Entomologist. As is common with phobias, many of the scientists traced their fears to a traumatic childhood experience.

Asked to score 30 animals on likability, the respondents ranked spiders 29th. (Only ticks drew more scorn.) Among the reasons given for detesting arachnids: the spiders‘ many legs and the “unsettling” ways they move. “Even filling out the survey creeped me out,” one researcher wrote.

If the spiders‘ eight legs are such a problem, then how about decapod crustaceans, from tiny shrimps to lobsters, with their ten legs? Or centipedes? Or millipedes?

See also here.

New Brazilian wasps discovered


Abernessia capixaba. Photo: Felipe B. Fraga/Cecilia Waichert

From Science, Space & Robots:

Two New Wasp Species Discovered in Brazil

Scientists have discovered two new wasp species in Brazil. One of the newly discovered wasp species, Abernessia capixaba, (pictured) is a gorgeous black color. The large wasps are about 3 centimeters in length. They belong to the rare pompilid genus Abernessia, which now consists of four species following the discovery of two new species.

The wasps parasitize spiders. Females of the wasps sting a spider and lay one egg on its abdomen. The wasps then put the spider in a specifically built net and bury it. The scientists discovered a connection between the sizes of prey and size of the offspring of the wasps. They say the larger wasps are believed to appear from nests containing larger prey.

Dr. Waichert, Utah State University, said in a statement, “There is a positive correlation between size of the spider preyed and size of the wasp produced in the next generation.”

The research paper was published here in ZooKeys.

Posted on November 26, 2013

New trapdoor spider species discovery


This is a video about trapdoor spiders, from the BBC’s Life in the Undergrowth documentary series.

From Wildlife Extra:

Three new species of trapdoor spiders

November 2013: Three new species of the wafer trapdoor spider genus, Fufius, have been discovered in Brazil – F. minusculus, F. jalapensis, and F. candango – by scientists from the Instituto Butantan in Sao Paulo. Spiders belonging to the Fufius genus are widely distributed throughout Central and South America, from Guatemala to south eastern Brazil.

The genus belongs to the Cyrtaucheniidae spider family which are also known as wafer trapdoor spiders. Many, but not all, make wafer-like doors to their burrows, while others build the cork-like doors found commonly in the true trapdoor spiders. Little is known about the biology of the enigmatic genus Fufius, but among the curiosities is that instead of burrows these spiders live in silken tubes in crevices, carefully prolongued with silk.

“What is curious about the genus Fufius is the wide distribution of the species. Normally, mygalomorphs have a very restricted distribution. Furthermore, the genus has species living in contrasting environments as the Amazon, Savannah, and Brazilian Atlantic forest. This makes the genus a potential model for biogeographic studies,” says one of the authors Dr. Rogerio Bertani.

The scientific description of these three new species is here.