Trapdoor spider species that stay local put themselves at risk



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A palisade trapdoor spider of the new species E. turrificus walks across the rainforest floor near Maleny, Queensland.
Jeremy Wilson, Author provided

Jeremy Dean Wilson, Griffith University

Several new species of trapdoor spiders found in Queensland are finally described in an article published this month in Invertebrate Systematics.

But each of the new species occurs in only its own single, isolated patch of rainforest in southeastern Queensland, and nowhere else.

Because these species have such tiny natural distributions, they are especially vulnerable to extinction.




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Unique spider burrows

These newly described spiders have been given the common name palisade trapdoor spiders because of the strange and unique burrows they construct. The entrance to the burrow projects out from the surrounding soil like a miniature turret.

The remarkable palisade burrows constructed by two different species of palisade trapdoor spider. The burrow entrances project from the surrounding soil.
Jeremy Wilson (left), Michael Rix (right)

Not only that, but each of the four new palisade trapdoor spider species constructs its own unique type of burrow.

One species, found in national parkland near Gympie and known scientifically as Euoplos crenatus, constructs a particularly elaborate burrow. The hinged door that covers the burrow entrance is adorned with several rounded lobes which project from the door’s circumference.

This marvel of natural architecture is constructed by the spider using silk and soil. No other spider species in the world constructs something similar.

This species was originally discovered by local naturalists Kelvin and Amelia Nielsen in 1999, who then guided researchers back to the discovery location in 2016 to collect specimens so the species could be formally named.

The burrow entrance of Euoplos crenatus, with its peculiar ‘crenate’ burrow door.
Michael Rix

Another species, Euoplos thynnearum, constructs a burrow entrance with a thick lip within which the burrow door sits. It’s found in the Mary Cairncross Scenic Reserve, a 55-hectare patch of subtropical rainforest popular with visitors to the Sunshine Coast hinterland.

This species is named after Elizabeth, Mabel and Mary Thynne, who originally donated the reserve land to the local council in 1941 to honour their mother Mary Thynne (née Cairncross). Currently, this species is known to occur only within the reserve and in other rainforest patches in the immediate vicinity.

Burrow entrances of the new palisade trapdoor spider species Euoplos thynnearum. This species is largely restricted to a single rainforest patch, occurring within Mary Cairncross Scenic Reserve near Maleny.
Michael Rix

Short-range species at risk

Species that only only occur in a very small area, like these new palisade trapdoor spider species, are known as short-range endemic species.

Although scientists are naming new species at a faster rate than ever before, estimates of the total number of species on Earth still suggest that most animal species have not been formally named. With so much work still to do, some scientists have chosen to prioritise work on particular types of animals that are especially vulnerable to extinction.

In 2002, Mark Harvey, an arachnologist from the Western Australian Museum, proposed that scientists should prioritise the discovery and description of short-range endemic species.

He reasoned that the small ranges of these species make them inherently vulnerable to extinction, and that identifying, naming and studying them is the first step to protecting them.

The strange burrows of the trapdoor spider species Euoplos crenatus project out from between the roots and leaf-litter on the bank of a creek in a rainforest patch near Gympie, Queensland.
Jeremy Wilson

Staying local

For trapdoor spiders, short-range endemism is the rule, not the exception. These spiders live their entire lives in a burrow. Juvenile spiders walk only short distances from their mother’s burrow, before constructing a burrow of their own.

Usually, these spiders will then remain in the same burrow for the remainder of their lives, enlarging it as they grow.

Examples of different trapdoor spider species from eastern Australia. Top left, Arbanitis longipes; top right, Heteromigas sp.; bottom left, Cataxia sp.; bottom right, Namea sp.
Jeremy Wilson

Adult male trapdoor spiders will also leave their burrow to breed, but will only travel relatively short distances. Over time, this extremely limited dispersal ability has led to the evolution of many different trapdoor spider species, each of which occurs in only a very small area.

Since 2012, a research team, led by Queensland Museum researcher Michael Rix, has been trying to discover and name all species of spiny trapdoor spider – this group includes the palisade trapdoor spiders, as well as other strange trapdoor spider species such as the shield-backed trapdoor spiders of Western Australia.

A shield-backed trapdoor spider from Western Australia, showing the distinctive hardened disk on its abdomen which the spider uses to ‘plug’ its burrow as a protection from predators.
Mark Harvey

So far, this project has led to the description of more than 100 new species from throughout Australia, some of which are already classified as threatened by federal and state governments.




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The most iconic of these is Idiosoma nigrum (also a shield-backed trapdoor spider), which is a listed threatened species.

The discovery of all these weird and wonderful spider species should remind us that Australia has some of the most remarkable invertebrate species in the world, and new species are waiting to be discovered in the national parks and reserves which occur around, and even within, our towns and cities – under our noses.

Next time you visit a national park, or drive past a patch of forest while commuting along Australia’s east coast, think to yourself, what might be living in there? Do those species occur anywhere else? And above all, if we lose that forest remnant, what unique species might disappear along with it?The Conversation

Jeremy Dean Wilson, Ph.D candidate, Department of Environment & Science, Griffith University, Griffith University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Malcolm Naden: Barrington Tops Warning for Travellers


Travellers to the Barrington Tops are being warned that outlaw and modern bushranger Malcolm Naden is suspected of hiding out in the remote wilderness area. There is currently a $50 000 reward for information that leads to his capture. He is the most wanted person in New South Wales, suspected of being involved in the disappearance of his cousin Lateesha Nolan and the murder of Kristy Scholes in 2005 at Dubbo.

Naden has sought refuge in the bush in the region bordered by Dubbo in the west and Kempsey in the east since 2005. During this time he has broken into homes, stealing non-perishable food items, camping gear and other equipment required to survive the bushland in which he hides and lives. He is known to be an expert bushman.

Naden first hid in the Western Plains Zoo at Dubbo and has since been known to have been in the vicinity of the Barrington Tops. In 2008 he was known to be in the vicinity of Stewarts Brook, in the western Barrington Tops area. In January 2009 he was known to be at Bellbrook, west of Kempsey. Three months ago he was known to be at Mount Mooney, in the northern Barrington Tops. It is thought that he is also responsible for similar break-ins around the Mount Mooney area in late August 2010. There have been a large number of break-ins across the region this year. He is believed to be armed, with a rifle having been stolen in one of the break-ins. Not all of the break-ins are confirmed as being committed by Malcolm Naden, but they all seem to bear his signature.

According to local newspapers, it is also believed that kangaroo carcasses have been found in the Barrington Tops, butchered in an expert manner. Naden was an abattoir worker and similar carcasses were found at the Dubbo zoo when Naden was hiding there.

The area in which Malcolm Naden is thought to be hiding was once the hideout for the bushranger known as ‘Captain Thunderbolt.’ Naden seems to be following in Thunderbolt’s footsteps in more ways than one.

For more on Malcolm Naden visit:

http://www.police.nsw.gov.au/can_you_help_us/wanted/malcolm_john_naden

http://coastmick21.blogspot.com/

http://www.smh.com.au/news/national/police-seek-man-on-run-after-cousin-found-dead/2005/08/21/1124562750384.html

http://www.australianmissingpersonsregister.com/Naden.htm

http://www.brisbanetimes.com.au/news/national/wanted-man-and-a-town-in-fear/2009/01/17/1232213416486.html

http://www.facebook.com/topic.php?uid=4884239637&topic=7725

http://www.theherald.com.au/news/local/news/general/danger-at-the-tops-break-ins-point-to-fugitive/1928579.aspx

http://www.smh.com.au/nsw/publics-help-sought-over-murder-cases-20100904-14v5u.html

Good News for Visitors to Uluru


303 There are always pros and cons when it comes to such issues as to whether or not people should be allowed to climb Uluru in the Northern Territory, Australia. To continue to allow visitors to climb the monolith is to go against the wishes of the traditional owners of the site (local aborigines), as well as to continue to impact on the local environs of the Uluru area.

Having said that however, the Uluru site is a site of major significance in Australia and to visitors the world over. If the site is looked after responsibly visitors should be able to climb the rock for many years to come with limited impact to the site.

Currently some 100 000 people climb the rock each year, though a number get no further than ‘chicken rock.’

Visitors will be able to continue to climb Uluru until such time as numbers dwindle significantly (to fewer than 20% of visitors climbing the rock), until such time as the climb is no longer the main reason for a visit to the rock or until a number of new visitor experiences (yet to be developed/thought out) are in place.

CROCODILE ATTACK NEAR COOKTOWN IN QUEENSLAND


A terrible tragedy is unfolding near Cooktown in Queensland, Australia. An Australian fisherman has probably been taken by a 6 metre crocodile on the Endeavour River while checking crab traps on foot. Arthur Booker, 62, from the town of Logan, south of Brisbane has not been seen since about 8.30am Tuesday morning.

The man and his wife were on a two-day holiday at the Endeavour River Escape campsite near Cooktown, north of Cairns in Queensland. Mr Booker had already packed his boat on the top of his 4WD vehicle in preparation to leave.

A local crocodile known as Charlie is the alleged culprit of Arthur Booker’s disappearance according to local Terry Rayner. However, Queensland Parks and Wildlife Service regional manager James Newman has said that there are other large crocodiles in the area.

Police are searching for the man but all that has been found is the man’s watch and footwear. The search will continue tomorrow.

BELOW: Footage of the Endeavour River, scene of the attack and the search for the victim.