Friday, 22 May 2015

Magnitude 4.2 Earthquake off the coast of Sandwich Bay, Kent.

The British Geological Survey recorded a Magnitude 4.2 Earthquake at a depth of 13 km off the coast of Sandwich Bay, Kent, in the southeast of England slightly after 2.50 am British Summertime (slightly after 1.50 am GMT) on Monday 11 May 2015. There are no reports of any injuries associated with this event, though there are unconfirmed reports of houses being damaged in the village off Flete, to the north of the epicenter of the quake, and people have reported feeling the event across all of Kent and as far away as Oxfordshire and Norfolk.

Map showing the epicenter of the 22 May 2015 East Kent Earthquake, and the areas where it was felt. BGS.

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. However, while quakes in southern England are less frequent, they are often larger than events in the north, as tectonic presures tend to build up for longer periods of time between events, so that when they occur more pressure is released.


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.

(Top) Simplified diagram showing principle of glacial rebound. Wikipedia. (Bottom) Map showing the rate of glacial rebound in various parts of the UK. Note that some parts of England and Wales show negative values, these areas are being pushed down slightly by uplift in Scotland, as the entire landmass is quite rigid and acts a bit like a see-saw. Climate North East.

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.

See also...

The British Geological Survey recorded a Magnitude 1.9 Earthquake at a depth of 6 km slightly to the northeast of the village of North Fambridge in Essex...

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Second Hampshire Earthquake in three days.
The British Geological Survey recorded a Magnitude 1.8 Earthquake at a depth of 4 km, roughly 3 km to the northeast of Winchester in Hampshire, England, at about 4.25 pm GMT on...


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Thursday, 21 May 2015

Pathogenic Oomycete Chromists from New Zealand, Hawaii and Côte d’Ivoire.


Oomycete Chromists are Fungus-like micro-organisms which cause a wide variety of infections in plants, such as Potato Blight and occasionally animals, such as White Rots in aquarium Fish. It is also likely that many live non-pathogenic lives in soil and water ecosystems, though the ecology of the group is not well understood outside species that cause problems for agriculture. The group were formerly thought to be related to Fungi, but genetic studies have shown them to be more closely related to Brown Algae and Diatoms, and in addition has revealed a great deal of diversity within the group, with species formerly classified together on the basis that they cause similar infections now known to be only distantly related.

In a paper published in the journal Phytotaxa on 10 April 2015, BevanWeir, Elsa Paderes and Nitesh Anand of Landcare Research in Auckland, New Zealand, Janice Uchida of the University of Hawaii at Manoa and ShaunPennycook, Stanley Bellgard and Ross Beever, also of Landcare Research, describe two new species of Oomycete Chromists from New Zealand and Hawaii and Côte d’Ivoire.

Both the new species are considered to be members of ‘Phytophthora Clade 5’, which is to say the fifth group assigned to the genus Phytophthora with a common ancestry closer to one-another than to other members of the genus. This clade has until now contained only two species, Phytophthora castaneae, which infects Chestnuts in Japan and East Asia, causing a form of Trunk Rot, and Phytophthora heveae, which has been shown to cause a variety of infections in a wide range of plants.

The first new species described is named Phytophthora agathidicida, meaning ‘killer of Agathis’ after the tree it infects, Agathis australis, the Kauri Tree of New Zealand. Kauris are Araucarian Conifers which formerly dominated many lowland areas in New Zealand. They are large, slow growing trees that were heavily harvested by European settlers in the nineteenth and early twentieth centuries and now have a very limited range, with old growth trees being found only in a few protected reserves and considerable effort being put into re-introducing the species across much of its former range. In 1971 it was noticed that Kauri Trees on Great Barrier Island in the Hauraki Gulf were suffering from a form of Collar Rot which caused bleeding lesions on the trunk and roots, yellowing of the foliage and thinning of the canopy, and occasionally tree death.

Phytophthora agathidicida. (A) Kauri stand on steep ridge displaying canopy thinning—“little-leaf” syndrome. Thereis a progressive dieback of the crown in response to parasitism of the cork cambium. (B) Bleeding resin (“kauri gum”) associatedwith collar-rot of lower trunk. The advancing lesion will spread laterally, eventually girdling the tree. (C) Diffuse non-patterned, colonymorphology after 10-days incubation at 20°C in the dark. (Left to Right) Clarified V8 juice agar, MEA, CMA, and PDA.(D) Scanning electron micrograph of oogonia. (E) Oogonia with amphigynous, tapering bases. (F) Oogonia with amphigynous, sub-globose antheridia (image courtesy of M.A. Dick, Scion). (G) Differentiation of the cytoplasm within papillate sporangia into acid fuchsin stained zoospores. (H, I) Papillate, globose sporangia. Scale bars are 10 μm. Weir et al. (2015).

Colonies of Phytophthora agathidicida produce globoseoogonia 3-4 days after becoming established. These oogonia are 22.2-45.0 μm in diameter and have slightly stipuled walls. These contain oospores 19.8-35.0 μm in diameter, and can develop into new colonies (check).

The control of Kauri Dieback is currently being managed by the Ministry for Primary Industries along with the Department of Conservation, Auckland, Bayof Plenty, Northland and Waikato Regional Councils and the Tangata Whenua Roopu, with measures being taken to prevent the spread of the disease by foot traffic and infected trees being treated with phosphite.

The second new species described is named Phytophthora cocois, which derives from Cocos, the formal generic name for Coconuts. This was first detected as a disease of Coconut Palms on KauaiIsland, Hawaii, in the 1970s and has subsequently spread to the islands of islands of Oahu, Hawaii and Maui, then in the 1980s was discovered in Côte d’Ivoire in West Africa. The infection leads to rotting and early drop of the fruits and eventually death of the Palms.


Phytophthora cocois. (A) Death of young Coconut fronds is the first common symptom of this disease. The young leaves wilt, dry, and are often bent or drooping into the tree canopy. (B) Premature loss of fruits is an early sign of disease. In later stages, fruit rots become more common. Infected green fruits have characteristic “green island” black to brown rots that expand irregularly and frequently form green areas surrounded by darkened diseased tissue. (C) Internal fruit rot. (D) Colony morphology of after 10-days incubation at 20°C in the dark. (Left to Right) Clarified V8 juice agar, MEA, CMA, and PDA.(E) Scanning electron micrograph of oogonia showing reflexed antheridium. (F–G) Oogonia showing some reflexed antheridia and mildly bullate oogonium ornamentation. (H) Differentiation of the cytoplasm within papillate sporangia into zoospores. (I, J) Sporangia shape variation. Scale bars are 10 μm. Weir et al. (2015).
  
Oogonia of Phytophthora cocois are globose and measure 22.3-35.0 μm in diameter, bearing spores measuring 19.8-29.7 μm. All measures to treat Coconut Palms once they become infected have failed, with the only means of controlling infection being to remove infected trees and fallen material from these trees as quickly as possible. In parts of Hawaii this has led to the effective clearance of large areas formerly inhabited by Coconut Palms. Phytophthora cocois appears to be host specific, and does not infect any other known host.

See also…

http://sciencythoughts.blogspot.co.uk/2015/04/three-new-species-of-diatoms-from-skin.htmlThree new species of Diatoms from the skin of a West Indian Manatee.                                      Most Marine Mammals are thought to host communities of Epizoic Algae living on their skins, though these have only been extensively studied in Cetaceans (Whales and Dolphins). Two closely related genera of...
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Scorpiops ingens: A new species of Scorpion from Tibet.


The Scorpion genus Scorpiops is a wide ranging and highly specious group of medium-sized, generally brown Scorpions. There are currently about a dozen species known from China, all of which are found in Tibet.

In a paper published in the journal ZooKeys on 8 April 2015, Shijin Yin of the College of pharmacy at South Central University for Nationalities, Yunfeng Zhang of the Department of Life Science at Tangshan Normal University, Zhaohui Pan of the Institute of Plateau Ecology at the Agriculture and Animal Husbandry College of Tibet University, Shaobin Li of the College of Life Sciences at Yangtze University and Zhiyong Di of the School of Life Sciences at the University of Science and Technology of China describe a new species of Scorpiops from Llasa in Tibet.

The new species is named Scorpiops ingens, which ‘refers to the size of the morphology’ of the species. It is described from four specimens, an adult male and female, an immature female and a juvenile male. The adult male is 74.6 mm in length, the female 75.9 mm (large for the genus). All the specimens are yellowish brown in colour.

Scorpiops ingens, male specimen in (1) dorsal and (2) lateral views, female specimen in (3) dorsal and (4) lateral views. Yin et al. (2015).

See also…

http://sciencythoughts.blogspot.co.uk/2014/08/two-new-species-of-scorpion-from.htmlTwo new species of Scorpion from Pakistan. There are thought to be about 50 described species of Scorpion from Pakistan, although these have not been systematically reviewed since 1900. Since 1995 there have been sixteen published studies on...
http://sciencythoughts.blogspot.co.uk/2014/05/a-new-species-of-wood-scorpion-from.htmlA new species of Wood Scorpion from Anatolian Turkey.                                                         Wood Scorpions of the genus Euscorpius are found in Europe from Iberia to Russia, as well as North Africa and southwest Asia, and is therefore one of the best studied Scorpion genuses, with eighteen described species grouped into four subgenera, and numerous subspecies. Despite this it is thought that there is still much to be learned about its taxonomy, and that...
http://sciencythoughts.blogspot.co.uk/2013/12/a-scorpion-from-late-devonian-of-south.htmlA Scorpion from the Late Devonian of South Africa.                                                                               Scorpions are thought to have been among the earliest Animals to colonize the land, with specimens...
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Flying Squirrels from the Late Miocene of Catalonia.


Flying Squirrels, Pteromyini, are today represented in Europe by only a single species, the Siberian Flying Squirrel, Pteromys volans, which is found in the Coniferous forests of Russia, Finland and other areas in the northeast of the continent, but in the lowland tropical forests of Southeast Asia as many as six species may be found living alongside one-another, able to co-exist because they occupy slightly different ecological niches. In the much warmer climate of the Miocene, Flying Squirrels are known to have been more numerous and diverse in Europe, with sites in Central Europe producing up to five species, suggesting a similar ecological diversity to that of modern Southeast Asia. However this level of diversity has not been recorded from the Late Miocene of Iberia, where three species have been recorded from Catalonia and none from the rest of the peninsula. This is in keeping with current reconstructions of the Miocene climate of Iberia, which suggests a more arid climate then the rest of Europe, with an intermediate climate in Catalonia, wetter than the rest of Iberia but dryer than most of Europe, a situation that persists to this day.

In a paper published in the journal Palaeobiodiversity and Palaeoenvironments on 8 May 2015, Isaac Casanovas-Vilar of the Institut Català dePaleontologia Miquel Crusafont at the Universitat Autònoma de Barcelona, SergioAlmécija of the Institut Català de Paleontologia Miquel Crusafont at the Universitat Autònoma de Barcelona and the Department of Anatomical Sciences at Stony Brook University and David Alba, also of the Institut Català de Paleontologia Miquel Crusafont at the Universitat Autònoma de Barcelona describe a series of new Flying Squirrel remains from the Late Miocene Can Llobateres 1 site in the Vallès-Penedès Basin of Catalonia, and discuss the implications of these for the climate and environment of Miocene Catalonia.

The Can Llobateres 1 was discovered in the 1920s during a road construction project and has been the subject of intermittent excavations ever since, particularly since the discovery of Ape remains at the site in the 1950s, which resulted in a prolonged collaboration between Spanish palaeontologist Miquel Crusafont and Johannes Hürzeler from the Museum of Basel, during which many tons of sediment were removed and sieved for microfossils, resulting in (amongst other things) a number of Flying Squirrel teeth being recovered in the 1960s. Excavations at Can Llobateres 1 were resumed in 2010 after a 12 hiatus by a team from the Institut Català de Paleontologia Miquel Crusafont, resulting in a number of new Flying Squirrel remains.

In order to determine that a Squirrel was capable of flying (or more technically gliding, since no squirrel can actually fly) it is necessary to be able to reconstruct a reasonable proportion of its post-cranial skeleton. This is not possible to do from any of the Catalan material, which comprises only Teeth, but it is usually possible to assign Rodents to species level from their teeth (as with most Mammals), and all of the Can Llobateres 1 material is assigned to species described elsewhere, enabling either a more complete knowledge of their anatomy or at least a confident assignment to the tribe Pteromyini (Flying Squirrels).

The species Albanensia grimmi, was first described from three cheek teeth from Marktl in Germany in the 1960s. It is distinctive within the genus Albanensia for its large size and the thicker posterolophid and stronger metalophid tooth cusps. In 1970 a partial jaw fragment with two molars and an isolated premolar were described from Miocene sites in the Vallès-Penedès Basin and tentatively assigned to this species, though they were larger than the German material and showed some morphological differences. Since then more specimens of the species have been described from other sites in Europe, notably Rudabánya in Hungary and Götzendorf and Richardhof-Golfplatz in Austria, which have led to a more complete understanding of morphological variation within the species. Due to this the Catalan material is no longer considered to be outside the range of morphological variation for the species, but is still exceptionally large. In addition to the previously described material, Casanovas-Vilaret al. describe a new specimen, a third molar, from Can Llobateres 1. They assign all these specimens to ‘Albanensia aff. grimmi’ (i.e. a member of the genus Albanensia showing affinities with Albanensia grimmi).

A molar of a Flying Squirrel from Can Llobateres 1 showing strong affinities to Albanensia grimmi. Casanovas-Vilaret al. (2015).

The species Miopetaurista neogrivensis was described from La Grive in France in 1970 to describe large members of this genus. In 1991 a single molar assigned to this species was described from Can Llobateres 1. Casanovas-Vilar et al. redescribe this specimen and agree with its taxonomic placement, as well as noting that other specimens of the species have recently been collected from other sites in the Vallès-Penedès Basin, which are likely to have formal descriptions published in the near future.

Second molar of Miopetaurista neogrivensis from the Late Miocene Can Llobateres 1 site in the Vallès-Penedès Basin of Catalonia. Casanovas-Vilar et al. (2015).

The species Miopetaurista crusafonti is well represented at Can Llobateres 1, with 17 isolated cheek teeth and six molar fragments recorded to date. This is considered to be a medium-sized member of the genus Miopetaurista, larger than the numerous species known from earlier Miocene deposits, but not as large as other Late Miocene species such as Miopetaurista neogrivensis, Miopetaurista thaleri and Miopetaurista tobieni. The species was originally described from a fragment of maxilla bearing the fourth premolar and first two molars from the Vallès-Penedès Basin, though this material is stored at the Faculté des Sciences de Montepellier and Casanovas-Vilar et al. have not seen it. The species has been described from several other sites in Catalonia, and may possibly also be present in southern France.

Specimens assigned to Miopetaurista crusafonti from the Late Miocene Can Llobateres 1 site in the Vallès-Penedès Basin of Catalonia. (b) Left fourth premolar, (c) left first or second molar, (d) right third molar collected in 2011, (e) right lower fourth premolar, (f) right first molar, (g) left second molar, (h) right third molar. Casanovas-Vilar et al. (2015).

The species Blackia miocaenica is considerably smaller and simpler than the other Catalan material. The small size and simple morphology of the specimens is considered enough to assign them to the genus, which contains only two species, and the measurements of the specimens place them within the species Blackia miocaenica rather than the slightly larger Blackia woelfersheimensis. The species has previously been recorded from the Early Miocene of Valencia (six million years older than the Can Llobateres 1 deposits), as well as from sites in the Czech Republic, Germany, Switzerland, France, Slovakia, Hungary, Romania and Austria. Casanovas-Vilar et al. report two first molars (one left and one right) of Blackia miocaenica fromCan Llobateres 1, the first time this species has been recorded from the Late Miocene of Catalonia.

Specimens assigned to Blackia miocaenica from the Late Miocene Can Llobateres 1 site in the Vallès-Penedès Basin of Catalonia. (l) Left first molar, (m) right first molar. Casanovas-Vilar et al. (2015).

Finally Casanovas-Vilaret al. report twoworn lower cheek teeth which fall loosely within the size range of two species, the Flying Squirrel Pliopetaurista kollmanni and the Ground Squirrel Spermophilinus bredai (which is also known from Can Llobateres 1). However the specimens have crenulated enamel, a feature associated with Flying Squirrels but not Ground Squirrels, so they are tentatively described as cf. Pliopetaurista sp. (i.e. probably a species of Pliopetaurista).

Specimens assigned to cf. Pliopetaurista sp. from the Late Miocene Can Llobateres 1 site in the Vallès-Penedès Basin of Catalonia. (j) Left fourth premolar (k) right third molar. Casanovas-Vilar et al. (2015).

Several decades of intensive sampling, including the sifting of many tons of sediment for microfossils, have now raised the number of Flying Squirrels found at Can Llobateres 1 to five, comparable with Miocene sites in central Europe and modern lowland forest ecosystems in Southeast Asia, though there is a clear disparity in the frequency of specimens, suggesting that some species were far more common than others.

As well as Flying Squirrels the Late Miocene sediments of the Vallès-Penedès Basin have produced a variety of other Mammals, such as Apes, Tapirs and Rhinoceroses, which indicate a humid forest environment. The sediments have also produced plant fossils such as Reeds, Figs, Palms and Cinnamon Trees, further supporting this environmental interpretation. Middle Miocene sites in Spain have produced evidence of three different ecosystems, herb-dominated wetlands, Legume-dominated woodlands with species such as Casia, Acacia and Caesalpina, indicative of a much drier climate and evergreen Laurel forests which could indicate wetlands or montane forests. Unfortunately most Late Miocene sites in Spain lack sufficient plant material for such interpretations, though sites in the Pyrenees have produced evidence of a mixed flora, with evergreen Laurels alongside more northerly species, such as Alders, Chestnuts, Willows and Elms.

The Late Miocene Vallès-Penedès Basin appears to have been home to wet forests with similarities to those of contemporaneous central Europe, though with a more restricted fauna; many central European species are absent and others, such as Flying Squirrels, were apparently much rarer. A total of five Flying Squirrel species from one site is exceptional, with only a few sites in Germany and France achieving this, but this detection cannot be divorced from the sheer scale of investigations that have occurred at Can Llobateres 1, where decades of excavations have taken place and tons of sediments sieved, and it is likely that many European sites which have produced more samples of common species with much less effort would also produce more species were they subjected to the level of sampling carried out at Can Llobateres 1.

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Syzygium pyneei: A new species of Myrtle from Mauritius.


The genus Syzygium is the largest within the Myrtle family, Myrtaceae, with over 1200 described species from across the tropical and subtropical regions of the Old World, including fifteen previously described species from Mauritius.

In a paper published in the journal PhytoKeys on 5 February 2015, James Byng of the School of Biological Sciences at the University of Aberdeen and the Herbarium of the Royal Botanic Gardens at Kew, Vincent Florens of the Department of Biosciences at the University of Mauritius and Cláudia Baider of The Mauritius Herbarium at the Ministry ofAgro-Industry and Food Security of Mauritius, describe a new species of Syzygium from Mondrain Reserve on the island of Mauritius.

The new species is named Syzygium pyneei, in honour of Kersley Pynee, a prominent Mauritian botanist who first noticed the species. Only two specimens are known, both growing on a ridge in the Mondrain Reserve at a height of about 520 m. The specimens were observed to flower in November 2006, reportedly for the first time in about 20 years. A few fruits were observed on the ground in January 2006, but no seedlings observed. The species is distinguished by its flowers, which are relatively large (over 2 cm), pinkish green in colour and grow directly from the trunk of the plant.

Sole recorded flowering event of Syzygium pyneei. Kersley Pynee in Byng et al. (2015).

Syzygium pyneeiis a large shrub reaching 3.5 m in height, with grey or creamy pink bark and waxy oval leaves, 10-15 cm in length and 4.5-9 cm in width. It produces fruit 20 mm in length containing one or two seeds, these being globular if one seed is present or half-moon shaped when there are two.

Syzygium pyneei (A) and (B) bark (C) close-up of branchlet (D) lower leaf surface (E) upper leaf surface. James Byng in Byng et al. (2015).

The Mondrain Reserve is a private reserve which has been fenced to keep out invasive alien Deer and cleared on invasive plants. The area surrounding the reserve has a similar habitat, but is dominated by alien species notably Psidium cattleianum (Peruvian Guavas), a highly invasive species known to be highly detrimental to other Mauritian native plants. A search of this forest revealed no further specimens of Syzygiumpyneei, suggesting that it has been excluded by competition with non-native species. Since only two plants are currently known the species is classified as Critically Endangered under the terms of the International Union for the Conservation of Nature’s Red Listof Threatened Species.

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Guavas, Psidium guajava, are fruit bearing trees in the Myrtle Family, Myrtaceae, closely related to Eucalyptus. They are native to Mexico, Central America and the Caribbean Islands, but have been introduced to many countries as a commercial fruit crop, the largest producers being Mexico, India and Brazil. Like...
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Madagascar is considered to be one of the world’s biodiversity hotspots. The island has an area of 592 750 km2 and is located in the southern Indian Ocean, giving it a tropical climate with a diverse range of...

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Landslide kills at least 78 people in Antioquia Department, Colombia.

At least 78 people have died after a landslide hit the village of La Liboriana in  Antioquia Province, Colombia on Monday 18 May 2015. The landslide, which was triggered by a flash flood, struck at about 3.00 am local time when most residents were sleeping, and swept a number of homes into the swollen Liboriana River. Between 50 and 80 people are still missing following the event, with rescuers searching a 40 km area of river beneath the village for bodies and survivors.

 Debris in the village of La Liboriana following the 18 May 2015 landslide. EPA.

May is the height of the rainy season in Antioquia Province, with rainfall averaging around 200 mm for the month, though this is uneavenly distributed and often results in flash floods. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall.

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Fifteen workers are missing following an inrush of gas and water at a gold mine at Riosucio in Caldas Province in the northwest of Colombia on Wednesday 13 May 2015. The incident reportedly happened during...
 
Fourteen people have been confirmed dead after two landslides in the city of Salvador in Bahia State, Brazil, on Monday 27 April 2015. The incidents happened in the Barro Branco and Marotinho neighbourhoods...
 
Seven people have been confirmed dead and six are still missing after a massive landslide hit the town of Chosica in Lima Province, Peru, on Tuesday 24...
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Cephalodasys interinsularis: A new species of Gastrotrich from the Bahamas.


Gastrotrichs are a phylum of minute animals, generally less than a millimetre in length, found in interstitial spaces in sediments (a phylum is the highest classification of organisms below that of kingdom; other animal phyla include Molluscs and Arthropods, the Vertebrates only have the status of a subphylum within the Phylum Chordata, which also includes animals such as Sea Squirts and Lancets). Their small size meant that they went unnoticed until the event of microscopy, with the group not being discovered until the 1860s. Despite this unfamiliarity they seem to be ubiquitous in marine sediments, and are also often found in non-marine settings.

In a paper published in the journal Zootaxa on 16 April 2015, Alexander Kieneke of the Deutsches Zentrum für marine Biodiversitätsforschung, AndreasSchmidt-Rhasea of the Centrum für Naturkunde at the Zoologisches Museum in Hamburg and Rick Hochberg of the University of Massachusetts Lowell describe a new species of Gastrotrich from the Bahamas.

The new species is placed in the genus Cephalodasys and given the specific name interinsularis, meaning ‘between the islands’, as it was discovered in sediments from a sandbank between Lee Stocking Island and Norman’s Pond Cay. Specimens of Cephalodasys interinsularis measured 471 μm in length (if this seems rather precise it is because Gastrotrichs are eutelic, meaning adults have a fixed number of cells), with a body divided into head, neck and trunk regions. The head is pair shaped and separated from the neck by a constriction, the trunk slightly wider than the neck. The body is flat, with a convex ventral side.

Cephalodasys interinsularis,schematic drawings. Left: Ventral view. Right: Combined dorsal and internal view. Abbreviations: an, anus; fo, frontal organ; fop, frontal organ pore; lc, locomotory cilia; me, mature egg; mgp, male genital pore; ov, ovary; ph, pharynx; pp, pharyngeal pores; sc, sensory cilia; TbA, anterior adhesive tubes; TbP, posterior adhesive tubes; TbVL, ventrolateral adhesive tubes; te, testis. Kieneke et al. (2015).

Cephalodasysinter insulariswas found in calcareous biogenic sand (sand made up of shell fragments) at a depth of two meters, alongside a variety of other Gastrotrich species, including members of the genera Macrodasys, Paraturbanella, Tetranchyroderma and Draculiciteria. It is not known if it is also found in other environments.

Cephalodasys interinsularis, light microscopic. (A) Ventral view showing the adhesive tubes and locomotorycilia. (B) Horizontal focal plane showing internal organs. Abbreviations:fo, frontal organ; in, intestine; lc, locomotory cilia; me, mature egg; ov, ovary; ph, pharynx; pp, pharyngeal pores; TbA, anterior adhesive tubes; TbP, posterior adhesive tubes; TbVL, ventrolateral adhesive tubes; te, testis. Kieneke et al. (2015).

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http://sciencythoughts.blogspot.co.uk/2014/05/a-new-species-of-gastrotrich-from-coast.htmlA new species of Gastrotrich from the coast of São Paulo State, Brazil.                              Gastrotrichs are microscopic animals of uncertain affinities, reaching at most 3 mm in size, though most species are far smaller. Less than eight hundred species have been described, living between...
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