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Sunday, 30 September 2012

Massive Earthquake deep beneath Columbia.

On Sunday 30 September 2012 slightly after 11.30 am local time (slightly after 4.30 pm GMT) the United States Geological Survey recorded a Magnitude 7.3 Earthquake 162.1 km beneath southeast Columbia, South America. This is a very large Earthquake and could potentially cause a great deal of damage, though its depth should help to mitigate this, since shock waves from quakes lose energy as they pass through rock in any direction - including up. Nevertheless the USGS estimate there is a 61% chance of the quake causing at least one fatality. At the time of writing no casualties or serious damage have been recorded, though people have reported feeling the quake across a large area of southern Columbia and neighboring Ecuador. The quake is not thought likely to be tsunamigenic.

Map showing the areas that suffered the worst shaking during the 30 September quake; greener areas felt more severe shaking than blue areas. USGS.

Columbia is on the west coast of South America and the western margin of the South American Plate, close to where the Nazca Plate, which underlies part of the east Pacific, is being subducted along the Peru-Chile Trench. The Nazca Plate passes under the South American Plate as it sinks into the Earth, this is not a smooth process and the plates repeatedly stick together then break apart as the pressure builds up, causing Earthquakes. As the Nazca Plate sinks further it is partially melted by the friction and the heat of the Earth's interior. Some of this melted material then rises through the overlying South American Plate, fueling the volcanoes of Columbia and neighboring countries.

The passage of the Nazca Plate beneath the South American Plate. Washington State University.


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A new species of Pachychilid Snail from western Java.

Pachychilid Snails are freshwater Gastropods found throughout the tropics. They have thick shells and operculi (plates used to cover the entrance of the shell) enabling them to live in turbulent waters. Many species give birth to live young, rather than laying eggs. Their closest relatives are marine Gastropods not other freshwater forms.

In a paper published in The Raffles Bulletin of Zoology on 29 February 2012, Ristiyanti Marwoto and Nur Isnaningsih of the Museum Zoologicum Bogoriense at the Research Center for Biology in Cibinong, West Java, describe a new species of Pachychilid Snail from the River Cibangbay in Tasikmalaya, West Java.

Map of Java showing the site where the new species was found (star) as well as known sites where the closely related Sulcospira testudinaria occurs. Marwato & Isnaningsih (2012).

The new species is placed in the genus Sulcospira, which is found in fast moving streams and rivers throughout south China, Southeast Asia and western Indonesia. It is given the specific name kawaluensis, which refers to the Kawalu Subdistrict, where the snails were found. Sulcospira kawaluensis is a 10-28 mm dark-coloured Snail with a roughly oval shell, comprising four-to-six flattened whorls in the adults, though this is the result of earlier whorls being worn away rather than only this number being produced. The Snails were found living on stones at depths of ~40 cm in an area of the Cibangbay which also had sandy and gravely areas. The species was largely distinguished from its closest relative, Sulcospira testudinaria, on the basis of the teeth on its radula (the radula is the tongue of a Gastropod, it is covered in hooked teeth, used to scrape up food).

Sulcospira kawaluensis. (D) Is the operculum. Other pictures are the whole shell. Scale bar is 10 mm. Marwato & Isnaningsih (2012).

The raduli of Sulcospira kawaluensis (Top) and Sulcospira testudinaria (Bottom). Images on the left are taken from directly above, those on the right from behind at an angle of 45°.


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New species of Cave Spider from Oregon.

Spiders are the most successful group of Arachnids and one of the most successful groups of Arthropods, with over 40 000 described species in over 100 families, distinguished by having eight legs, producing silk, and having a venomous bite. The the evolutionary lineage that produced Spiders, separate  from other Arachnids, appears in the fossil record in the Silurian, about 420 million years ago; though these earliest 'Spiders', called Trigonotarbids, lacked the ability to make silk. Silk producing Spiders appear in the fossil record in the Devonian, 386 million years ago. Since the evolution of the production of silk, Spiders have evolved to fill a wide variety of ecological niches, colonizing every environment except the polar regions and the oceans.

In a paper published in the journal ZooKeys on 17 August 2012, Charles Griswold of the Arachnology Lab at the California Academy of Sciences, the Department of Biological Sciences at San Francisco State University and Environmental Science, Policy and Management at the University of California, Berkeley, Tracy Audisio of the Arachnology Lab at the California Academy of Sciences, the Department of Biological Sciences at San Francisco State University and the Summer Systematics Institute at the California Academy of Sciences and Joel Ledford of the Arachnology Lab at the California Academy of Sciences and Environmental Science, Policy and Management at the University of California, Berkeley, describe a new species of Spider from cave systems in southwestern Oregon and Northwestern California.

The new species is named Trogloraptor marchingtoni, where Trogloraptor means 'clawed cave dweller' and marchingtoni honours Neil Marchington, a Deputy with the Deschutes County Sheriff's Office and a caver, biologist and conservationist. It is deemed to be sufficiently different from all other described species of Spiders that it is placed in a new family, the Trogloraptoridae, largely on account of the destictive claws on the limbs of the Spiders, which help them to run about on the ceilings of caves.

Trogloraptor marchingtoni.  Griswold et al. (2012).

Saturday, 29 September 2012

New species of Snail-eating Snake from western Panama.

Snail-eating Snakes of the genus Sibon are small, slender snakes native to Central America. They are nocturnal and often have banded patterns, causing them to resemble Coral Snakes, or bright colours resembling those of arboreal Pit Vipers. Biologists call this Batesian mimicry, whereby a species of animal or plant mimics a more harmful species in order to deter predators.

In a paper published in the journal Zootaxa on 17 September 2012, Sebastian Lotzkat and Andreas Hertz of the Senckenberg Forschungsinstitut und Naturmuseum and the Institute for Ecology, Evolution & Diversity at Goethe-University and Gunther Kohler of the Senckenberg Forschungsinstitut und Naturmuseum describe a new species of Snail-eating snake from the Caribbean side of the Cordillera Central mountain range in Western Panama.

 Map of western Panama showing the locations where the new snake was located (squares), and where the related S. annulatus (upright triangles), S. longifrenis (pentagon), S. nebulatus (inverted triangles), and S. perissostichon (diamond) have been found. Shading reflects altitude, with darker gray at greater height, cross hatching indicates protected areas. Lotzkat et al. (2012).

The new species is named Sibon noalamina, where noalamina derives from the Spanish 'no a la mina!', or 'no to the mine', a slogan used by indigenous Ngöbe communities opposed to mining in the Serranía de Tabasará, in order to show the authors support for 'the Ngöbe’s struggle to protect their territory and environment, which is home to the new species described herein and many others, from profit-driven destructive interventions'.

Sibon noalamina is a 546 mm+ slender snake with a brown and yellow striped pattern, destingiushed by having only 5 pairs of supralabial scales (scales on the upper lip) and by having slightly keeled scales on the third, fourth and fifth dorsal rows on the midbody. The snakes were found living on vegetation, in ridgetop cloud forest with abundant epiphyts.


Sibon noalamina in life. Arrows indicate the rows of keeled scales. Lotzkat et al. (2012).



 Line drawing of the head of Sibon noalamina, showing the patern of the scales. Scale bar is 1 mm. Lotzkat et al. (2012).

 Two further specimens of Sibon noalamina, showing colour variation. Lotzkat et al. (2012).

A new species of Blister Beetle from southeast Iran.

Blister Beetles (Meloidae) are a widespread group of Beetles, easily distinguished by their elongate shape and bright colours, which serve as a warning to predators. The Beetles secrete Cantharidin, a toxic chemical which acts as a blistering agent, when alarmed. The adult Beetles are primarily pollen and nectar feeders, but the larval forms are carnivorous, often consuming Bees or Grasshopper eggs.

In a paper published in the journal ZooKeys on 4 September 2012, Sayeh Serri of the Insect Taxonomy Research Department at the Iranian Research Institute of Plant Protection and Zhao Pan and Marco Bologna of the Dipartimento di Biologia Ambientale at the Università Roma Tre, describe a new species of Blister Beetle from Kerman Province in southeast Iran. The new species is based upon speciemens collected in 1969 and placed in the collection of the Hayk Mirzayans Insect Museum of the Iranian Research Institute of Plant Protection, the paper being part of a wider study on the Blister Beetles of Iran.

The new species is placed in the pre-existing genus and sub-genus Mylabris (Mylabris), and given the specific name barezensis, in reference to the Jebal Barez mountain range, where the Beetles were collected. Mylabris (Mylabris) barezensis is a 10-15 mm black Beetle with sub-oval brown spots.

Mylarbris (Mylabris) barezensis. Serri et al. (2012)

Thursday, 27 September 2012

Italian scientists face gaol over failure to predict Earthquake.

In late March 2009 the L'Aquila area of Central Italy was shaken by a number of small Earth tremors, prompting a meeting of the Serious Risks Commission, a group of Italian geoscientists charged with assessing the threat presented by geological hazards, such as Earthquakes or volcanoes. The scientists, having examined the available data, concluded that there was no way to predict whether the events were the precursors to a larger event or not, but that it would be wise to tighten building regulations in the area in the longer term.

On 6 April a Magnitude 6.3 Earthquake struck the area at a depth of 9.5 km, leading to severe damage to the medieval city of L'Aquila, with at least 3000 buildings damaged, several of which collapsed completely. A total of 308 people lost their lives, with a further 1500 being injured and about 65 000 being made homeless. 

The clear-up operation after the 6 April 2009 Earthquake in l'Aquila. Reuters.

In June 2010 public prosecutors in l'Aquila decided to bring legal action against the members of the committee present at the 31 March meeting, for failing to predict the quake. Charges of manslaughter were brought against six scientists and one civil servant; Bernardo De Bernardinis, then vice-president of the Italian National Service of Civil Protection, and now President of the Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA); Enzo Boschi, president of the L’Istituto Nazionale di Geofisica e Vulcanologia; Giulio Selvaggi, director of the Italian National Earthquake Center; Franco Barberi, a volcanologist at the University of Rome; Claudio Eva, professor of Earth Physics at the University of Genoa; Mauro Dolce, head of the seismic risk office of the Italian government’s Civil Protection Agency; and Gian Michele Calvi, Director of the European Centre for Training and Research in Earthquake Engineering.

In addition to the manslaughter charges damages of 50 million Euros are being sought by the city council in l'Aquila and a group called '309 Martyrs' which was founded by a local doctor, Vincenzo Vittorini, whose wife and daughter were killed in the quake. Prosecutors are seeking four year gaol sentences for the defendants (Italian law allows for a maximum sentence of 15 years for manslaughter). The trial has been adjourned until 9 October, when the defense will present closing arguments.

The trial has been widely criticized both in Italy and around the world, with scientists pointing out that Earthquakes are inherently hard to predict, and that a guilty verdict could make potentially make any form of scientific (or medical) prediction impossible in Italy. Over 5000 scientists have signed an open letter to Italian President Giorgio Napolitano, organized by the American Association for the Advancement of Science. Many critics have suggested that the trial is a smokescreen to cover widespread corruption in the Italian construction industry, and even the failings of the Berlusconi government in Italy, which was in the process of falling apart when the trial was initiated.

Italy is one of Europe's most Earthquake-prone countries, as it is caught in the collisional zone between Africa and Eurasia, with a tectonic plate boundary running the length of the country. The west of the country lies on the Eurasian Plate, but the east of Italy is on the Adriatic Plate, a micro-plate which broke away from the African Plate and is now sticking into the Eurasian Plate, underlying eastern Italy and the west of the Balkan Peninsula. In addition the African Plate is being subducted beneath the Eurasian Plate in the south of the country, fueling volcanism and Earthquake activity from Naples south to Sicily.

Map showing the tectonic plates underlying Italy and southern Europe, and the location of the l'Aquila Earthquake. Napoli Unplugged.

See also Modena Plane hit by second major EarthquakeEarthquake on the Modena Plane, northern ItalyEarthquakes shake northern ItalyTorino (Turin) rocked by mild earthquake and Earthquakes on Sciency Thoughts YouTube.

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Males of two species of Horse-fly described for the first time.

Horse-flies (Tabanidae) are widespread True Flies (Diptera) noted for their vicious bite, with many species considered to be pests of humans and livestock. Female Horse-flies typically require a meal of mammalian blood prior to reproducing, but males, if they feed as adults at all (like all flies they metamorphose from a totally unflylike form on maturity), feed on nectar or pollen. Because of this many species of Horse-fly are described from female specimens only, with the males being unknown, since only the females are attracted towards humans and domestic animals.

In a paper published in the journal Zootaxa on 16 July 2012, Tiago Kütter Krolow of the Coordenação de Ciências Biológicas at the Universidade Federal do Tocantins, Keith Bayless of the Department of Entomology at North Carolina State University and Augusto Loureiro Henriques of the Coordenação de Pesquisas em Entomologia at the Instituto Nacional de Pesquisas da Amazônia describe the males of two species of Horse-fly previously only known from female specimens. Both species are widespread in South and Central America, but not well studied, and hence are not well represented in entomological collections. 

The first species of Fly to have its male described is Eutabanus pictus, a predominantly black Fly considered to be a mimic of some forms of Flesh-fly (carrion eating Flies in the family Sarcophagidae) though the advantage to this is not clear. The males are described based upon specimens gathered in Brazil and Peru. The males are essentially similar to the females, but with with larger eyes and less prominent abdominal stripes.

Eutabanus pictus. Male (left) and female (right). Krolow et al. (2012).

The second species is Myiotabanus muscoideus, a black and white fly, again considered to be a mimic of some forms of Flesh-fly. The males described are from Mexico (further north than the previously known range of the species) and Guatemala. Again the males are very similar to the females, though the males have a less pointed abdomen and larger eyes.

Myiotabanus muscoideusMale (left) and female (right). Krolow et al. (2012).

See also New species of Silver Fly from Brazil.

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Tuesday, 25 September 2012

Planet discovered orbiting the metal-rich K-type star HD77338.

HD77338 is a metal-rich K0V-type Orange Dwarf Star 133 light years from Earth in the constellation of Pyxis. It has a radius 88% of that of the Sun and 93% of the Sun's mass; its effective surface temperature is 5370 K, compared to 5778K for the Sun.

In a paper published on 4 July 2012 on the online arXiv database at Cornell University Library, a team of scientists led by James Jenkins of the Departamento de Astronomia at the Universidad de Chile and the Centre for Astrophysics at the University of Hertfordshire announce the discovery of a planet orbiting HD 77338, made by the Calan-Hertfordshire Extrasolar Planet Search, reviewing data from the High Accuracy Radial velocity Planetary Search project.

HD77338b, as the planet is named (bodies in other stellar systems are named alphabetically, with stars given upper case letters and planets lower case letters), orbits the star (now HD77338A) every 5.74 days (138 hours) at a distance of 0.061 AU (6.1% of the distance between the Earth and the Sun), and has a minimum mass of 15.9 times that of the Earth (comparable to 14.6 Earth masses for Uranus and 17.2 Earth masses for Neptune in our own Solar System.

The mass of HD77338b compared to the mass of the planets of our solar system. The Visual Exoplanet Catalogue.

A new Therizinosauroid Dinosaur from the Early Cretaceous of Utah.

Therizinosaurs are an unusual group of Therapod Dinosaurs known from the Cretaceous of Asia and North America (with one dubious fossil from the Early Jurassic of China), usually placed within the Maniraptors, which makes them closely related to the early Birds. Unlike most Therapods they had well developed forelimbs with a wide range of movement and strongly curved claws and dentition suited to a vegetarian diet.

In a paper published in the journal PLoS One on 29 August 2012, Phil Senter of the Department of Biological Sciences at Fayetteville State University and James Kirkland and Donald DeBlieux of the Utah Geological Survey describe a new species of Therizinosaur from the Early Cretaceous Cedar Mountain Formation of western Utah.

The new dinosaur is named Martharaptor greenriverensis, or Martha's Raptor from Green River, in honour of Martha Hayden, who co-discovered the site that produced Martharaptor greenriverensis (now named the Hayden-Corbett Site) and has served as the assistant to three successive state paleontologists of Utah over a period of about 25 years (including the current office holder, James Kirkland).

Martha Hayden at the Hayden-Corbett Site. Utah Geological Survey.

The new dinosaur is described on the basis of three partial vertebrae, a radius and partial ulna (lower arm bones) a number of hand bones, the left scapula (shoulder blade), part of the ischium (part of the hip), a bone which might be part of the pubis (also part of the hip), several foot bones and a large amount of fragmentary bone material.

Vertebrae, scapula, forelimb bones, and pelvic bones of Martharaptor greenriverensis. (A)–Partial cervical neural arch, dorsal view. (B–E)–Cranial dorsal centrum in cranial (B), caudal (C), right lateral (D), and left lateral (E) views. (F–G)–Distal caudal centrum in lateral (F) and ventral (G) views. (H)–Possible ulna. (I)–Possible radius. (J–K)–Left scapula in lateral (J) and medial (K) views. (L)–Proximal end of ischium. (M)–Possible distal end of pubis Scale bar = 50 mm. acr = acromium process, ar = acetabular rim, gl = glenoid, hyp = hypapophysis, poz = postzygapophysis, pnp = pneumatopore, prz = prezygapophysis. Senter et al. (2012).

Manual bones of Martharaptor greenriverensis. (A)–Presumed metacarpal I. (B)–Presumed phalanx I-1. (C)– Penultimate phalanx. (D) Penultimate phalanx. (E)–Unidentified phalanx. (F)–Unidentified phalanx. (G)–Ungual of digit I. (H)–Ungual of digit I. (I)– Ungual of digit II. (J)–Ungual of digit II. (K)–Ungual of digit III. (L)–Ungual of digit III. Scale bar = 50 mm. Numbers on sub-figures refer to proximal (1), distal (2), dorsal (3), palmar (4), and side (5) views; for side views, whether the side is medial or lateral cannot be determined. Senter et al. (2012).

Metatarsals of Martharaptor greenriverensis. (A)–Left metatarsal I. (B)–Left metatarsal II. (C)–Presumed left metatarsal III. (D)–Right metatarsal II. (E)–Right metatarsal IV. Scale bar = 50 mm. Numbers on sub-figures refer to proximal (1), distal (2), dorsal (3), plantar (4), medial (5), and lateral (6) views. Senter et al. (2012).

Pedal phalanges of Martharaptor greenriverensis). (A–K)–Unidentified phalanges. (L)–Ungual of digit I. (M)–Ungual of unidentified digit (II, III, or IV). Scale bar = 50 mm. Numbers on  sub-figures refer to proximal (1), distal (2), dorsal (3), plantar (4), and side (5) views; for side views, whether the side is medial or lateral cannot be determined. Phalanx H articulates well with phalanx J, and phalanx G articulates well with phalanx I. Senter et al. (2012).

See also New species of Dromaeosaur from the Early Cretaceous of Utah, How did raptors use their claws? (and did it help them learn to fly?), A new Troodontid Dinosaur with an injured toeThe Ashdown Maniraptoran and Dinosaurs on Sciency Thoughts YouTube.
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Sunday, 23 September 2012

Two Earthquakes in Perthshire in two days.

On Friday 21 September 2012, a few seconds before 10.30 am British Summertime (a few seconds before 9.30 am GMT) the British Geological Survey recorded a Magnitude 1.4 Earthquake 2 km beneath the village of Comrie in west Perthshire, Scotland. Less than a day later, slightly before 8.40 am British Summertime (slightly before 7.40 am GMT) on Saturday 22 September, a second Earthquake, with a magnitude of 1.1, was recorded at a similar depth, 1.2 km to the northeast. These are small quakes, unlikely to cause any damage or casualties, and quite often to small to be noticed; although on this occasion the first was definitely recorded by witnesses in the village.

Map showing the location of the 21 & 22 September 2012 quakes. Google Maps.

As a rough rule of thumb, when you travel further to the north and west in Great Britain Earthquakes become more frequent, making Scotland (in particular western Scotland) the most quake prone area of the country. The precise causes of British Earthquakes can be hard to determine, as the country is not close to any active plate boundary, but is subject to tectonic stresses from a number of different sources.

Comrie lies on the Highland Boundary Fault; a suture that formed with the closure of the ancient Iapetus Ocean, roughly 500 million years ago, welding the ancient continents of Laurentia and Avelonia together as part of the Pangean Supercontinent, and incidentally causing the uplift and folding that formed the Caledonian Mountains. Prior to this event Scotland north of the fault formed part of Laurentia, an ancient continent mostly now part of North America, whereas Scotland to the south, was attached to Avelonia, along with England, Southern Europe and America east of the Catskills. However this is ancient history even by geological standards, and the fault is unlikely to be a cause of contemporary Earthquakes.

Map showing the location of the Highland Boundary Fault. British Geological Survey.

Scotland (along with the rest of Eurasia) 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. Closer to home there are lesser centers of expansion beneath the North Sea, the Rhine Valley and the Bay of Biscay, all of which excerpt pressure on Scottish rocks. Finally there is glacial rebound; until about 10 000 years ago much of the UK was covered by a thick layer of ice, pushing the rocks of the lithosphere down into the underlying mantle; this ice is now gone and the rocks are (slowly) rebounding, causing the occasional Earthquake in the process.

Witness accounts of Earthquakes can help geologists to understand these events, and the rock structures that cause them. If you felt either of these quakes you can report it to the British Geological Survey here. If you were in the area but did not feel the quakes then this information is also potentially useful and can also be reported.

See also Small Earthquake in the Western HighlandsSmall Earthquake on Islay, Argyle and Bute, Earthquake in Argyllshire, west Scotland, Isle of Islay shaken by two Earthquakes in two days and Earthquakes on Sciency Thoughts YouTube.

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Saturday, 22 September 2012

Two new species of Semiaquatic Rove Beetle from China.

Rove Beetles are an unusual-looking group of Beetles, distinguished by their short wing cases, which makes them look rather unbeetle-like. They are a successful group, with over 46 000 described species and a fossil record that dates back to the Triassic. Semiaquatic Rove Beetles of the genus Stenus are capable of swimming by producing secretions that reduce surface tension (often a problem for small insects caught in it).

In a paper published in the journal ZooKeys on 17 August 2012, Liang Tang and Li-Zhen Li of the Department of Biology at Shanghai Normal University and Jun-Wang Wang of the Qingliangfeng Nature Reserve administration describe two new species of Semiaquatic Rove Beetles from Guangxi and Zhejiang Provinces in China.

The first new species described is named Stenus huapingensis, meaning 'coming from Hauping'; the species is described from six male and twelve female specimens collected from the Huaping Nature Reserve in Guangxi Province. The Beetles were found living on Bamboo and Broadleaf Tree leaves in dense forest. They are 4-5 mm blackish Rove Beetles with yellowish brown legs and orange spots on their backs.

Stenus huapingensis in dorsal and ventral view. Scale = 1 mm. Tang et al. (2012).

The second new species is named Stenus zhujianqingi, in honour of Mr. Jian-Qing Zhu, who collected the specimens from which the species is described; seventeen male and three female Beetles from leaves in mixed Conifer/Broadleaf forest, in the Qingliangfeng Nature Reserve in Zhejiang Province. These are black Rove Beetles with redish legs, 4.0-4.3 mm in length.

Stenus zhujianqingi in dorsal and ventral view. Scale = 1 mm. Tang et al. (2012).

See also New species of Flat Bark Beetle (Cucujidae) from the Calabria Region of ItalyNew Ommatid Beetles from the Mesozoic of ChinaTwo new species of Rove Beetle from Zhejiang Province, China and New species of Bess Beetle from Guatemala.

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Earthquake on the Gulf of Corinth.

On Saturday 22 September 2012, slightly after 6.50 am local time (slightly after 3.50 am, GMT) a Magnitude 5.1 Earthquake hit central Greece, slightly to the north of the Gulf of Corinth and roughly 100 km northwest of Athens, at a depth of about 10 km, according to the United States Geological Survey. This is a fairly large quake, and quite shallow, with the potential to cause serious damage to buildings and potentially fatalities (the USGS estimate that a quake of this scale in this location would have a 32% chance of causing the loss of at least one life), though no damage or casualties have been reported on this occasion.

Map showing the location of the 22 September 2012 quake, and the areas likely to have suffered the most severe effects. Damage to buildings is likely within the innermost, green, circle.  USGS.

The geology beneath the Gulf of Corinth is slightly complicated. The Gulf forms part of the boundary between the Aegean and Eurasian Plates. This is a divergent margin, with the two plates moving apart, causing sinking in the centre of the Gulf, with the rocks on either side sinking along a series of faults, a structure known as a graben to geologists.

The graben beneath the Gulf of Corinth. The drawing apart of the Aegean and Eurasian Plates causes the lithosphere under the Gulf to thin, and the rocks of the crust to sink, splitting along a series of concentric faults on either side of the Gulf. Moretti et al. (2003).

However this is not the whole story, as to the south of The Peloponnese the African Plate is being subducted beneath the Aegean Plate along the Hellenic Subduction Zone, passing under The Peloponnese and the Gulf of Corinth (note this is oceanic plate attached to the north of Africa, not the continental African Plate).

The subduction of the African Plate beneath the Aegean Plate and the Gulf of Corinth. Turner et al. (2010).

Thus there are two potential causes of Earthquakes beneath the Gulf of Corinth; shallow faulting associated with the graben caused by the drawing apart of the Aegean and Eurasian Plates, and a deeper zone where friction between the subducting African Plate and the overlying Aegean and Eurasian Plates can lead to quakes. However depth is not the only guide to the cause of a quake, as the friction of the African Plate passing under the Aegean and Eurasian Plates also exerts stresses on the rocks in the graben, and can contribute to quakes there.


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Two new species of Pseudoscorpion from China.

Pseudoscorpions, or False Scorpions, are small carnivorous Arachnids resembling Scorpions without the stinging tail. Most species are between two and eight millimeters in length, although the largest can reach 12 mm. The fossil record of Peudoscorpions reaches back 380 million years, to the Late Devonian, when animals essentially similar to the modern forms are preserved.

In a paper published in the journal ZooKeys on 1 August 2012, Junfang Hu and Feng Zhang of the College of Life Sciences at Hebei University describe two new species of Pseudoscorpions in the genus Stenohya, (a small genus of Pseudoscorpions from east Asia) from China.

The first new species is named Stenohya pengae, in honour of Ms Yan-qiu Peng, who collected the samples from which the species is described. Mrs Peng collected 18 adult male and 25 adult female specimens, from the leaves of Chinquapin trees in the Damingshan National Nature Reserve, in the heavily forested Daming Mountains in the Guangxi Zhuang Autonomous Region, at an altitude of 1250 m.

Stenohya pengae is a dark brown Pseudoscorpion with reddish legs and claws. The females are larger than the males, between 3.9 and 5.0 mm in length, compared to 3.3-3.6 mm for the males.

Stenohya pengae, adult male. Hu & Zhang (2012).

Hu & Zhang also examined Pseudoscorpions collected by Fusheng Huang from Gushan Mountain in  Fujian Province in 1975, from which they identified one (female) specimen as not belonging to any previously described species. This specimen is formally described as Stenohya huangi, named after the collector. This is a yellow Pseudoscorpion 4.2 mm in length. 

Stenohya huangi, adult female. Hu & Zhang (2012).

Map showing the known distributions of members of the genus Stenohya in China. Hu & Zhang (2012).


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Friday, 21 September 2012

Burmese Snub-nosed Monkey found in China.

The discovery of the Burmese Snub-nosed Monkey, Rhinopithecus strykeri, was announced in January 2011 in a paper in the American Journal of Primatology, by a team of scientists led by Thomas Geissmann of the Anthropological Institute at the University Zürich-Irchel and the Asia Pacific Programme at Fauna & Flora International. The species was described on the basis of a dead male monkey and two skulls (one male, one female), and the skin of a juvenile, obtained from hunters in Kachin State in the northeast of Myanmar (Burma), plus descriptions of the Monkey's behavior also from hunters; no Monkey was observed by the scientists.

The intact Snub-nosed Monkey from the original description. Giessmann et al. (2012).

The Burmese Snub-nosed monkey has subsequently been discovered in China, as described in a second paper in the American Journal of Primatology in October 2012, by a team of scientists led by Yongcheng Long of The Nature Conservancy China Program.

In October 2011 forest guards in the Gaoligongshan National Nature Reserve spotted a group of unknown Monkeys, identified by local people as 'Meyah', but unknown to reserve staff. Two photographs were taken and sent to Yongcheng Long for identification, from which he concluded that these were most likely Burmese Snub-nosed Monkeys. At his request they gathered hair and feces left by the monkeys for DNA analysis, but this proved inconclusive.

A Chinese scientist inspecting a picture of a Snub-nosed Monkey.

Then in March 2012 two further sightings of the Monkeys were reported, this time material was obtained from which a positive DNA match was made, combined with further photographs, and film of the Monkeys in life. The film of the Monkeys can be seen here.

The Chinese State Forestry Administration is currently organizing a survey of the distribution of the Monkeys within China, and is reportedly interested in forming a cross-border conservation program with the Ministry of Environmental Conservation and Forestry in Myanmar.

Map showing the five known Rhinopithecus strykeri sites. Site numbers 1, 2, and 3 are in China and site numbers 4 and 5 are in Myanmar: (1) photo site, taken on October 16, 2011; (2) trace site on March 13, 2012; (3) video site on March 14, 2012; (4) the holotype site; and (5) the site the monkey group was seen on May 1, 2010. Long et al. (2012).


See also An Omomyid Primate from the Eocene of South LondonNew Mouse Lemur discovered in Madagascar, A re-evaluation of the Iwo Eleru skull, Ancient Ape Skull found in Uganda and Mammals on Sciency Thoughts YouTube.

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Thursday, 20 September 2012

New species of Daisy from Brazil.

Daisies of the genus Trichocline are found across southern South America, with a single species from Australia. They are small perennial herbs with red, yellow, orange, or rarely white flowers found on sandy or rocky grasslands, shrublands, or human-modified areas such as roadsides with exposed soil, mostly at high altitudes.

In a paper published in the journal Phytotaxa on 23 January 2012, Eduardo Pasini of the Programa de Pós-Graduação em Botânica at the Universidade Federal do Rio Grande do Sul and Mara Rejane Ritter of the Departamento de Botânica at the Universidade Federal do Rio Grande do Sul describe a new species of Trichocline  from southern Brazil and adjacent areas of Uruguay.

The new species is named Trichocline cisplatina, with cisplatina meaning beside the Platina, referring to the Río de la Plata. The plants were found in the Brazilian State of Rio Grande do Sul and Rocha Province, Uruguay. They grew on rocky or sandy soils on grasslands, shrublands and disturbed soils, on coastal plains up to an altitude of 400 m.

Map showing the known distribution of Trichocline cisplatina (black circles), and the closely related Trichocline catharinensis (black squares). Pasini & Ritter (2012).

Trichocline cisplatina is a herbaceous plant reaching 23 cm in total height when flowering. It is considered to by Vulnerable under the terms of the International Union for the Conservation of Nature's Red List, due to introduced commercial Pines and European Gorse in its range.

(Top) Photograph of Trichocline cisplatina in the wild. (Bottom) Line drawing of Trichocline cisplatinaPasini & Ritter (2012).

Environments colonized by Trichocline cisplatina. (Top) Sandy grassland. (Bottom) Hillside with shrubland vegetation. Pasini & Ritter (2012).


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Eruption on Gamalama.

Gamalama is a largely submerged volcano to the west of Halmahera in Indonesia. It's tip forms the island of Ternate, home to 145 000 people, and formerly the home of the Sultanate of Ternate, which at its height ruled much of what is now eastern Indonesia and the southern part of the Philippines. The island covers 76 km², and the summit of the volcano rises 1715 m above the sea. Gamalama is an active volcano, typically erupting several times a decade, it's last eruptive episode, in December 2011-January 2012, killed at least three people and produced a number of destructive lahars (mudflows triggered by volcanic activity) which destroyed several villages.

A lahar sweeps through a village on Ternate. Pusat Penanggulangan Krisis Kesehatan.

For the first two weeks of September 2012 the summit of Gamalama was obscured by cloud and fog, although what appeared to be a small plume could frequently be seen over the volcano. Then on the evening of 15 September an explosive eruption lead to ashfalls in the capitol (also Ternate). The next day rumbling was audible from the volcano, before a second eruption at about 2.15 pm, which produces a plume roughly 1 km high which drifted to the south and southeast, producing further ashfalls. The alert status on the island remains high, with people recommended to avoid going within 2.5 km of the summit.

Aerial photograph of a plume over Gamalama taken on Sunday 16 September 2012. Jakarta Post.

Halamahera and Ternate lie on the eastern edge of the Molluca Sea, which is underlain by the Molluca Sea Plate, a remnant plate being subducted from both sides. In the west the Molluca Sea Plate is being subducted beneath the Sangihe Plate, which underlies the northern part of Sulawesi, to the east it is being subducted beneath the Philippine Sea Plate, which underlies Halamahera and its surrounding islands. As it is subducted the Molluca Sea Plate is heated by friction with the overlying Sangihe and Philippine Sea Plates, and by the heat of the Earth's interior. Some of the melted material rises through the overlying plates, fueling the volcanoes of Halamahera and Sulawesi.

Map showing the location of Ternate at the eastern edge of the Molucca Sea. Google Maps.
Diagram showing the Molucca Sea Plate beneath the Molucca Sea. Hall & Wilson (2000).

See also Earthquake hits SulawesiEruptions from the Tompaluan Crater, Lokon-Empung, SulawesiVolcanic activity in the Halmahera Islands and Volcanoes on Sciency Thoughts YouTube.

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