Cærostris darwini, special guest on 1st of January 2011

The Darwin bark* spider, Araneidæ: Cærostris darwini, was recently discovered
in Madagascar by two enthomologists of the Smithsonian
National Museum of Natural History - Washington.

Females can cast giant and very strong webs across
streams, creeks and lakes, suspending the orb directly
above the water on anchor threads that can span up
to 25 m.

[Photo by Matjaz Kuntner]

With such a huge hunting ground, these spiders are never lacking for food.

[Photo by Ingi Agnarsson]

Like other orbweaver spiders, Caerostris displays extreme sexual size dimorphism
with large females and small males, which is manifested
in enigmatic sexual behaviors such as mate guarding,
male-male aggressiveness, genital mutilation, mate
plugging, and self castration.
The two enthomologists also pointed out the biology and
web architecture of the new riverine Cærostris species
due to it combining extraordinary web architecture with
exceptional silk mechanical properties [TechNews].

*[their name stems from the habits of at least some species to mimic dead bark, twigs or thorns].
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Click on > Journal of Arachnology to read more.

What's new about huge spiders ?

The Cerbalus aravensis has been found by a team of scientists from
the Department of Biology in the University of Haifa-Oranim in the giant
dune of Sands of Samar/southern Arava region of Israel, (Jan 2010).
But the Samar sands' site is desapparing : if once it covered as many
as 2.7 square miles, lately it's reduced to approximately 1 square mile.
Should this trend continues, the Cerbalus aravensis wouldn't survive.


(It's funny how, by enlarging Yael Olek's photo, an elderly person with white hair
and beard appears).


(Pictures Yael Olek and Roy Talbi)

This spider's leg-span can reach up to 14 cm., which makes it the largest
spider of its type in the Middle East. Even though details are still lacking to
enable a full analysis of its biology and of its population in the sands, the
scientists know that this is a nocturnal spider, mostly active in the hottest
months of the year, and that it constructs an underground den which is
closed with a "lifting door" made of sand particles that are glued together
to camouflage the den.
(more...)
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In Memoriam - C. Lévy-Strauss

Claude Lévy-Strauss
(Brussels 1908/Paris 2009).
The father of modern anthropology.





(europeimages)
Return to the Amazon.
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Female Nephila komaci, the hugest webweaving spider.

The Nephila komaci can be found in Madagascar and South Africa.
They can be up to three feet (one meter) wide and are a member
of the orbweaving spiders' group.

"In the PLoS ONE paper, Kuntner and Coddington described Nephila komaci
as a new species, now the largest web-spinning species known, and placed
it on the evolutionary tree of Nephila". (EurekAlert)


(Photos M. Kuntner)
1) a giant golden orb-web exceeding 1 meter in diameter: Nephila inaurata,
Rodrigues, Indian Ocean.
2) extreme sexual size dimorphism in Nephila spiders: Small male and large
female, Nephila pilipes, Singapore.
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Jumping now to another site, EarthTouch, for a beautiful video, taken early
in the morning, when the sun rays make the web's threads shine like gold,
which explains the spider's name.

Golden orb-web spider - Moremi Game Reserve, Okavango Delta, Botswana.

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* Previous post on Golden orb spider.

Gosh ! another serial killer spider !

Giant bird-eating spider struck in a backyard in Atherton, west of Cairns,
Australia.
- Spider is a Golden Orb Weaver
- Bird was a Chestnut-breasted Mannikin

Joel Shakespeare, head spider keeper at the Australian Reptile Park, said the spider
is a Golden Orb Weaver.
They usually feast on large insects and break down prey with their venom into a liquid
soup. It's unusual to see one eating a bird," he told 9msn.com.

Found on Telegraph, Oct 08/22, by Bonnie Malkin, Sidney... then redirected to 9msn.
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Thanks to Bonnie & co. from all PPG's spider admirers ! Yes, those who still come
to PPG to see once more the legendary camel spider !

Now, if you want to know more about this web weaver specialist...
go ahead > (Script : Damon Ramsey BSc.(Zool) Biologist Guide)

The 'Golden Orb Web Spiders', Nephila spp. are among the largest of the spiders
to build aerial webs.
They sit in the middle of their large 'orb' or circular shaped web usually with their
legs spread out and head pointing downwards.The abdomen is elongated and often
decorated with blacks, yellows and whites.
These spiders are referred to as a 'golden orb web' not because of the colours
sometime found on the spider (that can include golden yellows), but because, at the
right angle, the yellow silk of the web takes on a very delicate golden colour.

Unlike many spiders, they often leave their web up for some time, merely effecting
regular repairs. They can do this because their web of yellow silk is one of the strongest
amongst the spiders (Preston-Mafham and Preston-Mafham 1998).This is probably a
reflection of the large size of much of the prey they capture, for even the remains of
birds have been recorded in their webs (Raven 2000).

Most specimens of Golden Orb Web spiders observed are the females. This is because
the Nephila genus has the biggest size difference between females and males of any
spiders, with the tiny males sometimes being seen in the web.

(Smiling Golden Orb's portrait by Pagebao in Taiwan).

Before I leave you, I think it could be of some interest and pertinence to quote the
following sentence found somewhere in my searching about the Golden Orb :
"Mostly harmless, but they have inadvertently killed some 20 people over the years.
People died either from fright or tripping over as they tried to avoid or escape from
their rather strong webs."
Pat the spider now !
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[More posts about spiders...]

Legendary Camel Spider !

This blog was primarily intended for publishing anything I like...
well, today is 'Spider Day' because I've just found this...

As we just can't talk on and again about presidential love stories, fractals, UFOs, markets
evolution, mafiosi under arrest, Berlusco's devotion to money, hip hop, chaos theory, sacred
geometry, nightclubbers, popes, dahus, sashimis, or american elections... let's dedicate a few
line to these God's solifugae creatures...

They actually aren't spiders at all, they're solifugae. Along with spiders, they are members
of the class Arachnida and are called 'camel spiders' because they live in the desert. They
are somewhat of an urban legend and currently one of the most searched items on the
internet.

The camel spider stories began to spread during the 1990-91 Gulf War. Now, with the continued presence of U.S. forces in the Middle East, the stories are becoming legendary but most of them are completely untrue. These creatures are (usually) not dangerous to humans... (more)... except for their bites - I dare to say !


(by exspree).
A Matt Walker BBC article [on July 2010] explains, in a video, their hunting technique :
"Camel spiders have evolved a unique way to capture their insect prey."
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Selenite is a many splendoured crystal

The Naica Mine of Chihuahua, Mexico
and the Crystal Cave of Giants.

(Images : (c) Javier Trueba, Madrid Scientific Films).

In April 2000, brothers Juan and Pedro Sanchez
were drilling a new tunnel when... (read).

Giant Crystal Cave's Mystery Solved
National Geographic - April 7, 2007
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