A new species of Tardigrade from Latvia.

Tardigrades are small animals (adult sizes of 0.1-1.5 mm) distantly related to Arthropods and Onychophorans (Velvet Worms). They are plump segmented aquatic animals with eight legs, noted for their tolerance of extreme conditions. Tardigrades have been found living in hot springs, from under layers of ice in the high Himalayas, and in deep ocean trenches. They have been demonstrated experimentally to be capable of surviving temperatures from about -272℃ (only slightly above absolute zero) to about 151℃, and to be able to survive pressures from complete vacuums to about 6000 atmospheres (six times the pressure in the deepest ocean trenches), and are tolerant of high radiation levels and dehydration. Tardigrades have been demonstrated to be capable of surviving on the outside of a spacecraft in low Earth orbit for at least 10 days.

In a paper published in the journal ZooKeys on 13 May 2014, Krzysztof Zawierucha and Jakub Dziamięcki of the Department of Animal Taxonomy and Ecology at Adam Mickiewicz University, Natalia Jakubowska of the Department of Water Protection at Adam Mickiewicz University, Łukasz Michalczyk of the Department of Entomology at Jagiellonian University and Łukasz Kaczmarek also of the Department of Animal Taxonomy and Ecology at Adam Mickiewicz University, describe a new species of Tardigrade from the Gauja National Park in Latvia, as part of a wider study of Tardigrades in the Baltic States.

The new species is placed in the genus Minibiotus, and given the specific name formosus, meaning 'beautiful' Minibiotus formosus is a 113-236 μm colourless or white Tardigrade, with an external cuticle (skin) covered in round or oval pores. The species is described from 24 specimens collected from moss within the Gutmana Cave, roughly 45 m above sea level.

Minibiotus formosus in ventral view. Scale bar is 20 μm. Zawierucha et al. (2014).

See also...

 Three dimensional soft tissue preservation in a Myodocope Ostracod from the Herefordshire Lagerstätte.

Ostracods are small Crustaceans which conceal their bodies between two large valves in a bodyplan convergent with the unrelated Bivalve Molluscs and Brachiopods. They have an extensive fossil record, beginning in the...

 A new species of Earthworm from Spain.

Earthworms play a major role in the formation of soils in many parts...

 A new species of Phoronid Worm from Tomioka Bay, Japan.

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Asteroid 2011MD

At about 5.00 p.m. Greenwich mean time today (27th June 2011) Asteroid 2011 passed over Australia, Southern Africa and Central America at a distance of about 12 000 km or 32 times as close as the moon, which sounds pretty close, but, to give a sense of proportion, is also 36 times as far from the Earth as the International Space Station.

The asteroid was discovered five days previously (on the 22nd June) by the Lincoln Near-Earth Asteroid Research (LINEAR) project in New Mexico and given the designation 2011 MD, which means the fourth asteroid discovered in the period 16-30 June 2011. For the purpose of naming asteroids the year is split into 24 half month periods, numbered A to Y (I is not used).

An image of 2011MD, a faster moving streak against the background of stars.

2011MD is thought to be a house sized chunk of rock, between 10 and 45 meters across. This is small enough that it would break up in out atmosphere; small chunks might reach the ground but it would be unlikely to do any significant damage. Nevertheless reports of the near miss in the popular press have been peppered with stories about dinosaur killing asteroids. These step from the 1980 theory proposed by physicist Luis Walter Alvarez that the mass extinction 65 million years ago at the end of the Cretaceous Period, most noted for the loss of all non-avian dinosaurs, was caused by a massive meteorite impact, and the subsequent discovery of a global iridium layer at the same stratigraphic level by his son Walter Alvarez. This theory was popular throughout the 80s and 90s, particularly after the discovery of an impact crater off the Yucatan Peninsula in Mexico which seemed to fit the bill. Subsequent study by geologists has suggested that this crater is in fact to early to mark the end of the Cretaceous, and the impact theory in general is not as widely supported in the geological community as might seem to be the case to an outsider. Many geologists feel that volcanic activity associated with the collision of India and Asia, particularly the massive Deccan Traps flood basalts, may have caused a catastrophic climatic breakdown which caused the extinction. However the impact theory has rather more 'Hollywood' appeal than the volcanic one so it remains the theory most likely to be seen in the popular press, and it is still widely supported by astronomers and astrophysicists, partly out of tribal loyalty, and partly because they do not tend to follow geological journals closely.

Almost certainly not how the dinosaurs died out.

This is not to say that a sufficiently large asteroid impact couldn't cause devastation on such a large scale, or indeed far, far worse. The moon is thought to have been produced as the result of a collision between the Earth and a Mars-sized planet over four billion years ago, but as the solar system has aged the number of large objects floating about has steadily decreased; the odds of such a large impact happening now, let alone with an object we had not yet seen, are vanishingly small.

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