Friday 31 May 2013

A new species of Bumble Bee Scarab Beetle from the Early Cretaceous of Inner Mongolia.

Bumble Bee Scarab Beetles (Glaphyridae) are small, brightly coloured Scarab Beetles; they are active animals, and frequently resemble Bumble Bees when in flight. There are eight extant genera in the family, two of which have fossil records. Another two genera are known from the fossil record only. The fossil record of the family dates back to the Early Cretaceous.

In a paper published in the journal ZooKeys on 14 November 2012, Zhuo Yan of the Key Laboratory of Insect Evolution and Environmental Changes at the College of Life Sciences at Capital Normal University in Beijing, Georgiy Nikolajev of the Department of Biology and Biotechnology at the Al-Farabi Kazakh National University and Dong Ren, also of the Key Laboratory of Insect Evolution and Environmental Changes, describe a new species of Bumble Bee Scarab Beetle from the Early Cretaceous Yixian Formation at Liutiaogou Village in Ningcheng County, Inner Mongolia.

The new species is considered to be distinctive enough to be placed in a new genus, named Cretohypna, meaning Anthypna, from the Cretaceous; Anthypna being  a modern genus of Glaphyrid Beetle. It is given the specific name Cretohypna cristata, where 'cristata' means crested, a reference to a crest-like structure on the head. The species is described from a single male specimen. Cretohypna cristata is a 16.1 mm Beetle with an elongate oval body. 

Cretohypna cristata; (a) protibia, (b) mesotibia, (c) body in dorsal view, (d) metatibia and metatarsus. Yan, Nikolajev & Ren (2012).

Cretohypna cristataline drawings of holotype in (a) dorsal view, and (b) ventral view. Yan, Nikolajev & Ren (2012).

The Yixian Formation is probably 129.7-122.1 million years old, making it from the Barremian to early Aptian Age. The deposits are mainly lacustrine (from a lake) with occasional horizons of volcanic ash. The climate at the time of deposition interpreted as cool temperate, with mean air temperatures of 10 ± 4 °C. The formation is noted for its numerous fossil insects.

The approximate location of the site where Cretohypna cristata was found. Google Maps.

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Fifteen-year-old boy killed in Kathmandu landslide.

A fifteen-year-old boy was killed and two other people were injured  at about 6.15 am local time (0.30 am GMT) on Friday 31 May 2013, when house in the Khadapakhi  squatters settlement in Kathmandu was partially destroyed by a landslide, following heavy rains. The house was part of a settlement comprising around 250 buildings on a spoil heap left over from the construction of the Tribhuvan University Teaching Hospital in 1984. The settlement is considered to be at high risk during the monsoon system, when it is prone to such landslip events. 

The aftermath of the Khadapakhi landslide, seen from above. Nimesh Jang Rai/The Himalayan Times.

The boy who died has been named as Ram Bhagat Ram of Saptari District, who was taken to the Tribhuvan University Teaching Hospital by police but pronounced dead on arrival. The two injured people were named as Shivanandan Ram, 25, and Devilam Mandal, 60, both also from Saptari District. The three were renting the property, the owner of which did not live on-site. The three had apparently arrived in Kathmandu this week, with the intention of traveling on to the Gulf States in search of work.

Landslides are a common problem after severe weather events, as excess pore water pressure overcomes the sediments cohesion and allows it to flow downhill. Approximately 90% of all landslides are caused by heavy rainfall.

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Another worker killed in fresh Grasberg Mine cave in.

A worker has been killed in a cave in at the Freeport-McMoRan Copper & Gold operated Grasberg Mine in Indonesian West Papua, less than two weeks after an incident on 14 May 2013, in which 38 workers were buried, killing 28 of them. The incident is described as having happened when a tunnel collapsed at an underground 'drop point' (possibly the terminus of an underground railway). 

An emergency responce team removing the body of one of the workers killed in the 14 May 2013 cave in. Freeport Indonesia.

Work at the mine was suspended following the 14 May incident, but partially resumed on Wednesday 29 May, officially for 'mining facilities and equipment maintenance'. Between 35 and 40% of the workers at the mine are said to have resumed work, with the All-Indonesian Workers Union in the Chemical, Energy and Mining Sectors, which represents about 18 000 of the 24 000 workers at the mine advising its members not to return till a full enquiry into the incident has been carried out. The union has also been angered by the suspension of pay negotiations following the 14 May cave in, something Freeport Indonesia claims it has done 'out of respect' but which the union describes as 'unethical'.

The Indonesian Government has also expressed opposition to the resumption of work at the mine, with Energy and Mineral Resources Minister Jero Wacik claiming that work should not resume without his permission, which will not be given until the results of an enquiry are in. However the company is claiming the decision to resume work is their responsibility, not that of the government.

The Grasberg Mine produces around 220 000 of concentrated ore per day, making it the world's second most productive copper mine. Around 80 000 tonnes of tonnes of this are from the underground mine, with the remainder from a large pit mine also at the site.

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Four children feared dead after after Philippine Landslide.

Four children are feared to have died after a house in which they were playing was  buried by a landslide in Sayao Village in Zamboanga Province, on Mindanao Island in the Philippines. The incident occurred at about 2.30 pm local time (6.30 am GMT) on Tuesday 28 May 2013, when the abandoned property was hit by a slide of mud, soil and rock, covering it completely. After two days of searching none of the children have been located, leasing to fears that they have died. The incident occurred following heavy rains.

The approximate location of the 28 May 2013 landslide. Google Maps.

Landslides are a common problem after severe weather events, as excess pore water pressure overcomes the sediments cohesion and allows it to flow downhill. Approximately 90% of all landslides are caused by heavy rainfall.

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Thursday 30 May 2013

A new species of Leaf Mining Moth from Brazil.

Moths of the Family Gracillariidae are found throughout the world except on Antarctica and some remote islands. Their larvae are leaf-miners, worm-like caterpillars that live in tunnels inside leaves. Some groups of Gracillarid Moths are specialist miners of the leaves of some of the most ancient groups of Angiosperms (flowering plants) such as Laurels and Magnolias, and fossils leaf mines that resemble those of the Moths have been found in fossilized leaves from the Cretaceous of North America, which also suggests this is an ancient association. However the oldest fossils of the Moths themselves are from (Eocene) Baltic amber, and there is no way to connect these moths to the leaf mines, so it is quite conceivable that the Moths have only recently colonized these plants, and that the burrow shape is coincidental, simply a good shape for a leaf mine in this sort of leaf.

In a paper published in the journal Zootaxa on 12 December 2012 a team of scientists led by Rosângela Brito of Departamento de Zoologia at the Instituto de Biociências at the Universidade Federal do Rio Grande do Sul, describe a new species of Gracillarid Moth from the Atlantic Rain Forest of southern Brazil.

The new Moth is placed in the genus Phyllocnistis, which has a global distribution and which is known to target a wide range of plants, though the majority are found in North America, where their larvae feed particularly on Laurels, Magnolias and Witch-Hazels. The new species spends its larval stage on the Passion Vine, Passiflora organensis, the first member of the genus found on a plant found on a plant of the Family Passifloraceae, and the first from the Brazilian Atlantic Rainforest.

It is given the specific name Phyllocnistis tethys, after Tethys, a Titan goddess in the Greek mythology; the wife of Oceanus, and the mother of rivers, springs, streams, fountains and clouds, a reference to the cloudy and humid nature of the area of the Brazilian Atlantic Rain Forest where the new species was first found.

Phyllocnistis tethys is a ~2.5 mm feathery whit Moth with yellow markings on the tips of its wings. It is known only from a single site at an altitude of 900 m in the Atlantic Rainforest of Rio Grande do Sul State.

Phyllocnistis tethys. (A) Adult, wings spread, pinned, dorsal view. Scale bar is 0.5 mm. (B) Adult, wings folded, on Passiflora organensis leaf, in dorsal view. (C) Adult, wings folded, on Passiflora organensis leaf, in lateral view. Brito et al. (2012).

The eggs of Phyllocnistis tethys are laid on the underside leaves of Passiflora organensis, a Passion Vine known to horticulturalists as the Organensis Passionflower or Batwing Passionflower. The emergent larvae drill into the leaves of the vine, where they remain for the rest of the larval part of their life cycle, molting three times within the leaf; the final larval stage, typically slightly under 5 mm long, does not breed, but spins a silk cocoon within which it  pupates, emerging as an adult.

The leaves and flower of Passiflora organensis. Ruhr Universität Bochum.

Larval and pupal morphology of Phyllocnistis tethys under light microscopy. (A) First larval (“sap-feeding”) instar, dorsal and ventral views. Scale bar 100 μm. (B) Third larval (“sap feeding”) instar, dorsal and ventral views. Scale bar 400 μm. (C) Fourth larval (“cocoon spinning”) instar, dorsal and ventral views. Scale bar 400 μm. (D–F) pupa, dorsal, ventral and lateral views. Scale bar 300 μm. Brito et al. (2012).

Life history of Phyllocnistis tethys: (A) Passiflora organensis shoot twining around on a fern at the type locality, showing several leaves with leaf mines at different development stages. Scale bar 100 mm. (B) Leaf mine on abaxial leaf surface (open and closed arrows, respectively, indicate empty chorion on leaf surface, and sap-feeding larva seen through transparent mine). Scale bar 1 mm. (C) Egg containing developing embryo. Scale bar 0.2 mm. (D) Freshly hatched larva (indicated by closed arrow; open arrow indicates green frass lines left within the egg chorion. Scale bar 0.3 mm. (E) Third-instar (sap-feeding) larva. Scale bar 1 mm. (F) Detail of frass lines and damage on leaf parenchyma, left by the larva within the mine. Scale bar 1 mm. (G) fourth-instar (spinning) larva. Scale bar 1 mm. (H) Passiflora organensis containing several pupae, seen by transparency (indicated by arrows). Scale bar 20 mm. (I) A pupal chamber in detail, showing a pupa by transparency. Scale bar 5 mm. (J) Pupa, lateral view. Scale bar 0.5 mm. (K) Pupal exuvium protruded (arrow) from mine exit hole, just after the adult emergence. Scale bar 2 mm. Brito et al. (2012).

See also The taxonomic implications of host preference in Large Blue ButterfliesNew species of Owlet Moth from Sichuan Province, ChinaFive new species of Snout Moth from ChinaNew Tiger Moths discovered in east Asia and New species of Leaf-Mining Moth from northern Chile.

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Two people killed as Hurricane Barbara makes landfall on Mexican south coast.

Hurricane Barbara made landfall on the southern coast of Oaxaca State in Mexico at around noon local time on Wednesday 29 May 2013, with sustained wind speeds of 120 km/h accompanied by a storm surge 1.5 m above normal tidal levels and up to 50 cm of rain. Two people are known to have died in the storm already, a 61 year-old American surfer and a local man in his twenties who was trying to cross a swollen river, and it is feared more lives will be lost. Mexico has already suffered a number of casualties due to flooding, landslides and weather-related traffic accidents in the past week.

The intensity and path of Barbara. The storm has been growing in strength as it moved northward, only being upgraded to a hurricane classification slightly before landfall, and is expected to lose strength as it passes over land, however it has already proven to be a dangerous storm with two known casualties. The thicker line represents its path to date, the thinner line its projected path. The circles are the areas that could potentially be affected by winds in 9, 21 and 33 hours; the circles get bigger as the storm is subsiding due to uncertainty about the path of the storm. Tropical Storm Risk.

Hurricanes, and tropical storms in general, form due to heating of air over the sea in tropical zones. As the air is heated the the air pressure drops and the air rises, causing new air to rush in from outside the forming storm zone. If this zone is sufficiently large, then it will be influenced by the Coriolis Effect, which loosely speaking means the winds closer to the equator will be faster than those further away, causing the storm to rotate, clockwise in the northern hemisphere and anticlockwise in the southern hemisphere.

Whilst the high winds associated with hurricanes are extremely dangerous, the real danger from such storms is  the flooding. Each millibar drop in air pressure can lead to a 1 cm rise in sea level, and large hurricanes can be accompanied by storm surges several meters high. This tends to be accompanied by high levels of rainfall, caused by water picked up by the storm while still at sea, which can lead to flooding, swollen rivers and landslides; which occur when waterlogged soils on hill slopes lose their cohesion and slump downwards, over whatever happens to be in their path.

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Wednesday 29 May 2013

Earthquake off the coast of Isla Vista, California.

A Magnitude 4.6 Earthquake occurred at a depth of 7.4 km roughly 2 km off the coast of Isla Vista, California, slightly before 7.40 am local time (slightly before 4.40 pm GMT) on Wednesday 29 May 2013, according to the United States Geological Survey. This is a moderately large Earthquake in an area with a fairly high population, though California is used to and prepared for such events. The USGS estimates there is a 26% chance of a quake of this size in this area causing at least one fatality, though no damage or injuries have been reported from this event. The quake was felt as far away as Los Angeles, 150 km to the east.

The location of the 29 May 2013 Earthquake. Google Maps.

California is extremely prone to Earthquakes due to the presence of the San Andreas Fault, a tectonic plate margin that effectively bisects the state. The west of California, including Isla Vista, Santa Barbara and Los Angeles, is located on the Pacific Plate, and is moving to the northwest. The east of California, including Fresno and Bakersfield is on the North American Plate, and is moving to the southeast. The plates do not move smoothly past one-another, but constantly stick together then break apart as the pressure builds up. This has led to a network of smaller faults that criss-cross the state, so that Earthquakes can effectively occur anywhere.

Movement on the San Andreas Fault. David Lynch/

Witness accounts of Earthquakes can help geologists to understand these events and the underlying structures that cause them. If you felt this quake (or if you were in the area but did not, which is also useful information) then you can report it to the United States Geological Survey here.

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Asteroid 1998 QE2 to pass Earth at about 5 800 000 km on Friday.

Asteroid 1998 QE2, a 2.7 km chunk of spacerock, will pass the Earth this week, coming closest to the Earth at about 9.00 pm (GMT) on Friday 31 May 2013. Since this is about 15 times as far from the Earth as the Moon, the asteroid will not present any threat to life on Earth, but it should be possible to see it with a descent home telescope (in the constellation of Libra), and planetary scientists hope to be able to map its surface with Earth-based radar telescopes.

The comparative orbits of Earth and 1998 QE2. JPL Small Body Database Browser.

Asteroid 1998 QE2 has an elliptical 3.77 year orbit that brings it to within 5.79 million km of the Earth's orbit at it's closest to the Sun - though it never actually crosses our orbit, so it is not an immediate threat (potentially a future encounter with another object could alter its orbit making it more dangerous, but this is not a likely occurrence). At its furthest point it reaches 3.8 AU from the Sun (i.e. 3.8 times as far from the Sun as the Earth), roughly mid-way between the orbits of Mars and Jupiter.

The full orbit of 1998 QE2. JPL Small Body Database Browser.

The designation 1998 QE2 has nothing to do with either the British Monarchy of the Cunard liner; rather it is a product of a naming convention based upon when asteroids are found; in this instance 1998 Q implies the object was discovered in the second half of August 1998, and E2 implies it was the 55th object discovered in this period (the numbers  1-25 are represented by the letters A-Z, excluding I, and numbers indicate extra runs through the alphabet; thus E is 5, E1 is 30 and E2 is 55).

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Magnitude 3.8 Earthquake off the Lleyn Peninsula, North Wales.

A magnitude 3.8 Earthquake at a depth of 8 km occurred off the coast of the Lleyn Peninsula in North Wales, slightly after 4.15 am British Summertime (slightly after 3.15 am GMT) on Wednesday 29 May 2013, according to the British Geological Survey. While this is not a large Earthquake and is unlikely to have caused any damage or injuries, it is exceptionally large for Wales, and was felt as far away as Southport in Lancashire, with many people on the Peninsula reporting being waken by the quake and hearing a loud rumbling noise that went on for about 30 seconds.

Map showing the location of the 29 May 2013 Earthquake, and places where people reported feeling the quake. British Geological Survey.

Earthquakes become more common as you travel north and west in Great Britain, with the west coast of Scotland being the most quake-prone part of the island and the northwest of Wales being more prone  to quakes than the rest of Wales or most of England.

The precise cause of Earthquakes in the UK can be hard to determine; the country is not close to any obvious single cause of such activity such as a plate margin, but is subject to tectonic pressures from several different sources, with most quakes probably being the result of the interplay between these forces.

Britain is being pushed to the east by the expansion of the Atlantic Ocean and to the north by the impact of Africa into Europe from the south. It is also affected by lesser areas of tectonic spreading beneath the North Sea, Rhine Valley and Bay of Biscay. Finally the country is subject to glacial rebound; until about 10 000 years ago much of the north of the country was covered by a thick layer of glacial ice (this is believed to have been thickest on the west coast of Scotland), pushing the rocks of the British lithosphere down into the underlying mantle. This ice is now gone, and the rocks are springing (slowly) back into their original position, causing the occasional Earthquake in the process. 

Witness accounts of Earthquakes can help geologists to understand these events, and the structures that cause them. If you felt this quake, or were in the area but did not (which is also useful information) then you can report it to the British Geological Survey here.

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Seven people killed in Mexican landslide.

Seven people have been killed when a part of a hill collapsed onto the Mexico City-Queretaro road in Tepeji del Rio municipality in Hildago State, covering cars with mud, rocks and trees on Sunday 26 May 2013. At least five cars were buried by the slide, though all those killed were in two vehicles; five people in a taxi and two in a van, another four passengers in the van received hospital treatment. The incident comes during a severe hail and rain storm that caused flooding in the area. People in the area had apparently raised concerns about the hill above the road, but highway officials had not found any problems.

Rescuers at work on the Mexico City-Queretaro road on 27 May 2013. Xinhua/Susana Martinez.

Landslides are a common problem after severe weather events, as excess pore water pressure overcomes the sediments cohesion and allows it to flow downhill. Approximately 90% of all landslides are caused by heavy rainfall.

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Evacuations ordered after activity on Copahue.

Argentina and Chile have declared a mandatory evacuation zone of 25 km around the Copahue Volcano, which straddles the border between the two countries, roughly 500 km to the south of the Chilean capitol Santiago. The volcano started to suffer violent tremors on Monday 27 May 2013, and has released a large volume of gas, though as yet there has been no other eruptive activity.

The Copahue Volcano. Mono Andes/Wikimedia Commons.

Copahue comprises a chain of nine craters along a 2 km east-west line, with the most recent, still active, crater at the eastern end. This chain sits within the 400 000 to 600 000 year old, 6.5 by 8.5 km Trapa-Trapa Caldera, which in turn sits inside the older (more than 2.5 million years old), 15 by 20 km Caviahue Caldera. The active crater contains an acid lake, the Del Agrio, which is fed by acidic hot springs at its east end. The lake is noted for frequent fumerole (gas) emissions, and occasional explosive events.

Copahue is an extremely active volcano, having last erupted on 7 May 2013, when it produced a 350 m ash plume. A series of eruptions in December 2012-January 2013 produced numerous explosions and crater iridescence, as well as ash columns rising as high as 4.6 km. 

Copahue, like other volcanoes in the Andes, is fed by the subduction of the Nazca Plate beneath the South American Place along the west coast of the continent. As the Nazca Plate sinks into the Earth it passes under South America, and at the same time is partially melted by the heat and pressure of the planet's interior. More volatile elements in the melted magma to rise up through the overlying South American Plate, fueling the volcanoes of the Andes.

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Monday 27 May 2013

An early Woodwasp from the Early Cretaceous of Brazil.

The Hymenoptera are one of the largest groups of insects, comprising Sawflies, Wasps, Ants and Bees. The earliest members of the group were Sawflies, which appeared around the beginning of the Late Triassic. Sawflies have caterpillar-like larvae that consume plant material, gaining their name from their saw-like ovipositor (egg-laying organ), which is adapted to cutting into plants, where eggs are laid. Woodwasps are considered to be the oldest group of Wasps, descended from Sawflies and ancestral to all other Wasps, and therefore Ants and Bees. They have a needle-like ovipositor, that is used to inject eggs into either a plant or animal host. Wasps, and later Ants and Bees, underwent dramatic evolutionary radiations during the Cretaceous, coinciding with the rise of the flowering plants.

In a paper published in the journal Systematic Entomology on 8 November 2011, Lars Krogmann of the Staatliches Museum für Naturkunde in Stuttgart and  and André Nel of the Muséum National d’Histoire Naturelle in Paris describe a new species of Woodwasp from the Lower Cretaceous Crato Formation of northeastern Brazil.

The new species is named Cratoenigma articulata, where Cratoenigma means 'enigma from Crato' and articulata refers to an artculation on the upper surface of the thorax. Cratoenigma articulata is an 11 mm Insect preserved in limestone. It is clearly a Woodwasp, but does not appear to belong to any known group of Woodwasps, having a mixture of features from a variety of groups. Krogmann and Nel suggest that this may imply that Cratoenigma articulata is the sister group to all other Woodwasps, and therefore all other Wasps, Ants and Bees.

Cratoenigma articulata. Scale bar is 2 mm. 

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The first leaves; leafy plant fossils from the Early Devonian of South China.

Plant leaves are split into two groups by botanists; microphylls, which are simple plates of undifferentiated cells, as found in Mosses and Liverworts, and megaphylls, or true leaves, which have cellular differentiation and veins; such structures are not necessarily flat, Pine needles are true leaves. The earliest known fossil plants, such as the Silurian Cooksonia and Baragwanathia and the plants of the Early Devonian Rhynie Chert, lacked true leaves, but by the Middle Devonian plants with leaves are widespread.

In a paper published in the April 2013 edition of the Chinese Science Bulletin, Hao SouGang and Xue ZinZhuang of the Key Laboratory of Orogenic Belts and Crustal Evolution at the School of Earth and Space Sciences at Peking University describe a number of leafy fossil plants from the Earlt Devonian Posongchong Formation of Yunnan Province in southern China, which is thought to be roughly contemporaneous with the Rhynie Chert. These fossils have previously been described separately, but this paper provides a review of the flora in English.

The first plants discussed are the Trimerophytes Psilophyton and Pauthecophyton. Middle Devonian Trimerophytes are often thought to be the earliest true leafy plants, or at least the ancestors of them, since there is dispute as to weather their 'leaves' can be classed as true leaves, with some authors referring to them as 'incipient fronds' or 'proto-leaves'. Hao and Xue describe these plants as having 'branch-leaf complexes' comprising a vascular bundle, thin-walled cells, and epidermis. 

Trimerophytes from the Posongchong Formation. (a) Psilophyton dawsonii, has a lateral branching system with an outer cortex comprising a continuous layer of thick-walled sterome, a structure common in axes of many primitive tracheophytes but absent in Rhynie plants. Scale bar is 5 mm. (b) Pauthecophyton gracile has lateral dichotomous branching system with terminal sporangia. Scale bar is 2 mm. Hao & Xue (2013).

Estinnophyton yunnanense has clearly differentiated stems and leaves, though the leaves are simple lateral dichotomous branching systems. These are arranged in pseudowhorls with three to six leaves per  gyre. This plant has been theorized to be ancestral to the Sphenopsids (horsetails).

Estinnophyton yunnanense. (c) Partial reconstruction of a vegetative axis, with lateral, once or twice-bifurcated leaves arranged in low spirals or pseudowhorls. (d) Lateral forked leaves. Scale bar 1 mm. (e) Lateral forked leaves with sporangia. Scale bar 1 mm. Hao & Xue (2013).

Celatheca beckii has main axes and three-dimensionally arranged lateral branches. The branches undergo several rounds of division before ending in dichotomous appendages, recurved near the end with cylindrical tapering tips. Fertile structures superficially resembling a synangium (three-lobed spore bearing structures found in some fern-like plants) are found on the lateral branches.

Celatheca beckii. (f) Reconstruction of a branching system as a branch-leaf complex with more-or-less pinnate arrangement of ultimate dichotomous appendages. (g) Reconstruction of a vegetative specimen showing a branch-leaf complex with multi-ordered branching systems and ultimate appendages more or less pinnately arranged. Sometimes an ultimate appendage is borne below the branching point. (h) Fertile structures showing sporangia (right arrow) and incomplete leaf-like appendage (left arrow). (i) Fertile structure showing sporangia (arrow). (j) Fertile structures showing sporangia and complete leaf-like structure (arrow). All scale bars 2 mm. Hao & Xue (2013).

Polythecophyton demissum resembles Pertica spp., a genus of plants from the Early-to-Middle Devonian of northeastern North America. It has a clear architecture of fertile structures but lacks anatomy and vegetative organs. The fertile branches are terminated by pendulous umbrella-shaped fertile structures which may initially bifurcate, after which each component bears three to four alternately arranged, short axes, which divide into branchlets terminated by numerous slender fusiform sporangia in pairs or in groups of three or four.

Polythecophyton demissum. (k, l) Terminal portion of fertile branch showing umbrella-shaped fertile systems and pendulous sporangial clusters. Scale bars 5 mm. (m) Schematic reconstruction of branching of a fertile structure and reconstruction of attachment pattern of sporangia. Scale bar 4 mm. Hao & Xue (2013).

Eophyllophyton bellum has laminar (flat) leaf pairs bourn laterally or terminally on axes. These form a growth series with the youngest leaves at the tip. The leaves show clear venation, and have tips curving inwards towards each-other. Most of these leaves appear to bear spherical sporangia arranged in rows on the underside, in a similar manner to modern Ferns. 

Eophyllophyton bellum. (a) Lateral branch with small laterals terminating in leaf pairs, either vegetative or fertile. Scale bar 3 mm. (b) Lateral branch showing an acropetally developmental transformation: the basal part has mature leaf pairs, and the distal part has younger ones (left arrow) and recurved sterile tips (right arrow). Scale bar 3 mm. (c) A branch-leaf complex with ultimate appendages (dichotomy with recurved tips) borne alternately along the axes, showing a roughly pinnate arrangement. Scale bar 3 mm. (d) A leaf pair (two leaves, arrow indicates the faint appearance of bases of a leaf pair). The leaf margins of the laminate divisions are deeply incised and curved. A pinnately divided, laminar leaf reflects a branching system as shown in (c). Scale bar 1 mm. (e) A fertile pair with two leaves shows a reduced, expanded branching system with weak lamination. The lower arrow points to common base of the two leaves, and upper arrow points to a sporangium. Scale bar 1 mm. (f) A fan-shaped leaf with more conspicuous lamination. Note that the margins of the laminar divisions are deeply incised (arrows). Scale bar 1 mm. (g) Fertile leaf cluster with numerous sporangia. Scale bar 1 mm. Hao & Xue (2013).

Eophyllophyton bellum. (a) Reconstruction of a leaf showing that laminar divisions are not held in one plane. (b)–(e) Transverse sections at different levels of the structurally preserved lamina, showing veins and mesophyll cells. (b) Through petiole of a leaf, note the main vein. Note main vein in (d) and observe that main vein in (c) and second-order veins in lateral divisions in (c) and (d) are missing. (e) Through distal region, note leaf vein. Scale bar is 0.5 mm compared to (a) and 250 μm compared to (b-e). Hao & Xue (2013).

Eophyllophyton bellum. Numerous isolated fertile leaves on the bedding surface. Scale bar is 3 mm. Hao & Xue (2013).

AdoketophytonStachyophyton and Dibracophyton have fertile leaf-like appendages (sporophylls or bracts) to constitute a strobilar structure with different sterile organs, but they are neither microphyllous
plants nor megaphyllous plants. Adoketophyton has vegetative axes which dichotomously divide in three dimensions with some laterals ending in terminal, circinately coiled tips, a form of branch-leaf complex unlike that in any more recent plant. It has been placed within several plant groups, but is now considered to be in a class of its own, though related to the earliest ancestors of several groups.

Adoketophyton subverticillatum. (a) Abaxial view of a sporophyll with a fan-shaped blade. Scale bar 2 mm. (b) Lateral view of a fertile unit, with a sporangium adaxially attached on the sporophyll base. Scale bar 1 mm. (c) Transverse section of a sporophyllous lamina, showing variation in cells. Arrow points to probable tracheids. Scale bar 60 μm. (d) Transverse section of distal part of a sporangium, showing structure of sporangial walls and marginal dehiscence grooves and thickenings (left arrow). Also note that the cells in the outermost layer are elliptical. Their long axes are perpendicular to the surface of the wall. Among them can be found prominent intercellular spaces (right arrow); dark material between two walls presumably represents a broken tapetal layer. Scale bar 60 μm. Hao & Xue (2013).

Reconstruction of Adoketophyton parvulum. Scale bar 10 mm. Hao & Xue (2013).

Stachyophyton yunnanense has lateral leaf-like branches arranged helically along main axes. The leaf-like branches generally show a fan-shaped form showing morphological similarities to leaves with many divisions expanding distally in one plane, but they are rigid and unreduced, departing from the main axes. They show great variability, from the branching in a plane to more “webbed”, fan-shaped patterns with planation, and their distal segments are highly dissected divisions with rounded or cuneate tips . These may retain an axial nature with a planate branching system but have distal foliar divisions and thus perform some photosynthetic functions.

Stachyophyton yunnanense. (a) Leaf-like branch with distal parts that dichotomize 4-8 times forming terminal branchlets, to which are attached strobili with helically arranged sporophylls (arrow). Scale bar 8 mm. (b) Lateral vegetative 'leaf-like branches'. Scale bar 15 mm. Hao & Xue (2013).

Reconstruction of Stachyophyton yunnanense. Scale bar 15 mm. Hao & Xue (2013).

Dibracophyton possesses terminal strobili. Each fertile unit comprises a stalked long-elliptical sporangium, with dehiscence into two equal valves, and two discrete longovate bracts covering the sporangium from above and below. The sterile axes of Dibracophyton bear helically dichotomous appendages with curved or round tips. Some dichotomous appendages are alternately borne at the basal areas of the fertile axes. Besides the independent vegetative axes, a few vegetative appendages are distributed along the area of the fertile axes, and that the long upper region of the fertile axes lacks any appendages.

Reconstruction of Dibracophyton acrovatum. Scale bar 10 mm. Hao & Xue (2013).

Hao & Xue suggest that rather that megaphylls originating only once and all higher plants sharing a common ancestry, leaves may in fact have had multiple origins, evolving on at least four separate occasions and possibly as many as nine times.

Proposed phylogeny for early leafy plants. plotted against geological time showing the appearance of major clades, including euphyllophytes in Late Silurian-Early Devonian. Hao & Xue (2013).

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The effect of parasitic Nematodes on European Eels.

European Eels, Anguilla anguilla, have a complex life-cycle; they hatch from eggs in the Sargasso Sea in the southwest North Atlantic, then migrate to European inland waterways where they grow for up to 25 years before returning to the Sargasso to breed. This life-cycle exposes leaves them exposed to a number of human-related threats, including overfishing, habitat loss and pollutants, and the species has suffered a dramatic decline in numbers since the 1970s, to the alarm of conservationists. Since the 1980s the species is also known to be widely suffering from infection from an invasive parasitic Nematode worm, Anguillicoloides crassus, which probably entered Europe with imported Eels from Southeast Asia, and against which the European Eel apparently has no natural defenses. 

The European Eel, Anguilla anguilla. Animal Base/Staats-und Universitätbibliothek Göttingen.

Anguillicoloides crassus infects the swim-bladders of Eels, and from where it drains blood. The Nematode has a much shorter life-cycle than the Eel, and an infection will purge itself since eggs are laid outside the host, but multiple infections can damage or even destroy the swim-bladder, removing the Eels ability to control its own buoyancy and killing it. Anguillicoloides crassus is not reliant on the Eels to survive, it can use a variety of hosts including many types of Fish and Crustaceans, so a reserve of Nematodes is likely to remain in the environment even if the Eels become locally extinct, so that new Eels recolonizing an area will be infected immediately.

The parasitic Nematode Worm, Anguillicoloides crassusAquaNIS.

Eels raised in the laboratory and infected with Anguillicoloides crassus, tend to be underweight compared to other Eels of the same age. Such infected Eels are approximately the same length as uninfected Eels, but are notably thinner. Based upon this studies of Eels in the field have tended to use weight-to-length ratio as a proxy for Nematode infection, though this has never actually been tested in wild Eels.

In a paper published in the Proceedings of the Royal Society Series B Biological Sciences on 16 January 2013, a team of scientists led by François Lefebvre of Station Biologique de la Tour du Vala, describe the results of a study of Eels in a complex of brackish lagoons in the Rhône River delta, in which Eels were actively checked for Nematode infection and signs of past infection (scarring of the swim bladder), and the rate of infection was compared to the weigh-to-length ratio of the Eels.

Surprisingly this study found that the relationship between infection rate and age appeared to be reversed in wild Eels compared to laboratory-raised Eels; fatter Eels showed signs of bearing a heavier parasite load that thinner Eels, suggesting that the model used in many previous studies is completely wrong and must be reassessed. Lefebvre et al. suggest that while infection in the laboratory is deliberate and not influenced by diet, this is not the case with wild Eels, which become infected by consuming Nematode eggs, thus making more voracious Eels more likely to become infected, while giving Eels that consume less, either through more selective feeding or for other reasons, a better chance of avoiding the Nematodes.

See also An invasive Serpulid Worm in the La Encrucijada Biosphere Reserve, MexicoBlue Flatworms invade Menorca and A living fossil eel discovered in Palau.

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Fossil Pandas from the Middle Miocene of Spain.

Giant Pandas, Ailuropodinae, are highly specialized members of the Bear Family, Ursidae, adapted to eat a diet of tough, woody plants, principally Bamboo. Only one species of Giant Panda lives today, but several fossil species are known, the earliest being the 8 million year old Ailurarctos lufengensis, from the Late Miocene of China, leading palaeontologists to conclude that the lineage probably diverged from other members of the Bear Family in Central Asia in the Early Miocene.

In a paper published in the journal PLoS One on 14 November 2012, a team of scientists led by Juan Abella of the Museo Nacional de Ciencias Naturales-Centro superior de Investigaciones Científicas in Madrid, describe a new species of Giant Panda from two specimens from the Middle Miocene of northeastern Spain, thought to be between 11.2 and 11.8 million years old.

The new fossils are named as Kretzoiarctos beatrix, where Kretzoiarctos means 'Kretzoi's Bear' after Miklós Kretzoi, a prominent Hungarian Palaeontologist of the mid-twentieth century. The specific name comes from Agriarctos beatrix, a species name that was given to two teeth found from the same area in 2011; this is now considered to belong to the same species as the new material, and removed from the genus Agriarctos. The new material comprises a fragmentary right mandible.

The right mandible of Kretzoiarctos beatrix in (1a) labial, (1b) lingual and (1c) occlusal views. Abella et al. (2012).

Line drawing of the same. Marta Palmero in Abella et al. (2012).

Teeth originally described as Agriarctos beatrix. (1) Left premolar in (A) occlusal, (B) lingual and (C) buccal views. (2) Right front molar in (A) occlusal, (B) lingual and (C) buccal views. Abella, Montoya & Morales (2011).

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Sunday 26 May 2013

Two people injured by gas pipeline explosion in Jiangxi Province, China.

Two people are reported to have been injured by an explosion on China's 2nd West-to-East Natural Gas Pipeline in Shangli County in Jiangxi State, which occurred in the morning of 26 May 2013. The explosion occurred in an industrial zone about 300 m from a highway service station, and several hundred people are said to have been knocked over by the force of the blast. Local authorities are investigating the cause of the blast.

The location of Shangli County. Google Maps.

The 2nd East-to-West Natural Gas Pipeline carries about 30 billion cubic meters of gas per year from gas fields in Xinjiang Province and the Central Asian Republics to the industrialized regions of Yangtze and Pearl River deltas, where it is used in industry and homes. Any long-term disruption to this supply route is likely to have severe consequences. China is the world's largest user of natural gas, much of it imported from Central Asia via the two East-to-West Pipelines. The country plans to open a third pipeline in the near future and has longer term plans for at least two more.

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Seven people killed by Landslide in Shaanxi Province, China.

Seven people including three children were reportedly killed when a landslide hit a two-story dormitory belonging to a mining company in Cangcun, Shaanxi Province, at about 10.00 am local time (2.00 am GMT) on Saturday 25 May 2013. A further 12 people recieved hosprital treatment after being injured in the incident, though none of these is considered to be seriously hurt; local authorities are satisfied everyone in the building has been accounted for and rescue work was halted at 7.00 pm local time.

Rescue workers at the site of the Cangcun dormitory destroyed by the 25 May landslide. Xinhua.

The event has been linked to exceptional weather experienced in the region, which has recorded the highest rainfall in 13 years, leading to a series of floods and landslides. It is unclear if the hillside that gave way is affected by mining activity.

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