New record and southern range extension for the Mearn's grasshopper mouse ( Onychomys arenicola Mearns, 1896) in Veracruz, Mexico

Mearn’s grasshopper mouse ( Onychomys arenicola ) in Mexico is found primarily in the central and northern states. This is the first report of the genus Onychomys in the state of Veracruz, based on 7 captured specimens (3 collected). This finding extends the species’ known distribution by approximately 470 km east-southeast. In addition, this record increases the alpha diversity of terrestrial mammals for the state of Veracruz to 192 species.     

An extant, indigenous tortoise population in Baja California Sur, Mexico, with the description of a new species of Xerobates (Testudines: Testudinidae)

An extant, indigenous desert tortoise population is reported from the cape region of Baja California Sur, Mexico. This population is described and figured as a new species, Xerobates lepidocephalus , distinct from all other North American tortoises including Xerobates agassizii , X. berlandieri , Gopherus flavomarginatus , and G. polyphemus . Xerobates lepidocephalus , or the scaly-headed tortoise, whose range is known only from an extremely small area in the gulf-drainage mountains just south of La Paz, appears to be a peninsular relict whose closest living relative is probably X. agassizii . However, carpal bone affinities connote a close relationship between X. lepidocephalus and the Oligoeene species X. laticunea from Wyoming and Colorado, suggesting that the former species may be one of the more primitive contemporary tortoises of the Xerobates lineage. Such evidence indicates that X. lepidocephalus is not of vicariant origin resulting from the formation of the cape of Baja California. Scaly-headed tortoises likely ranged, and may yet be discovered, in other medium-elevation mountain ranges of the cape.     

Reflection of the Neogene–Quaternary phylogeography in the recent distribution limiting climatic factors of eight Mediterranean Phlebotomus species (Diptera: Psychodidae)

The diversification of Mediterranean Phlebotomus species occurred during the Neogene and Quaternary periods. The climatic and geographical history of the Mediterranean area plausibly influenced the climatic requirements of recent sand fly species. Our aim was to investigate the European zoogeography and the climate-based ecological groups of eight Phlebotomus species considering the phylogeography of the studied taxa. Jaccard index calculation, hierarchical cluster and principal component analyses were performed. The results of Jaccard-coefficient calculations may indirectly refer to the former existence of three possible glacial refuges of sand fly populations in Europe: an Iberian, an Apennine and a Balkan Peninsula–Asia Minor refuge. Three main climatic groups of the studied sand fly species were distinguished, namely the so-called ‘Trans-Mediterranean’, ‘East Mediterranean’ and ‘West Mediterranean’ groups. Our results suggest that the ancestor of Phlebotomus similis and Phlebotomus sergenti was adapted to the hot, dry summer Mediterranean climate during the late Neogene. The third member of this climate group, Phlebotomus papatasi because of co-adaptation shows similar climatic requirements as P. similis and P. sergenti. The five Larroussius species studied should have evolved under moister climatic conditions. Species of the ‘West Mediterranean’ group were adapted to the milder and wetter oceanic climate of Atlantic coasts. The species of the ‘East Mediterranean’ group diversified under the less balanced climate of the East Mediterranean. The recent climatic requirements and the European distribution of the studied species is the consequence of the complex Quaternary–Neogene geographical and climatic history of their former habitats in the Old continent. The adaptation of the ancestors of the studied sand fly species to the changing geographical and climatic factors of Europe are discussed.     

A snapshot of a high density seahorse population in a tropical rocky reef

Seahorses are fishes that suffer high trading pressure in the international market. Three species have been recorded in Brazil, Hippocampus reidi, Hippocampus erectus and Hippocampus patagonicus, already classified as threatened or data deficient. Guaíba Island is an ecologically relevant site due to its position between two bays in Rio de Janeiro state. The present study aimed to survey the seahorse population of Guaíba Island, verifying several population structure parameters. Eight diving sites were selected around the island. Only the longsnout seahorse H. reidi was recorded. The population showed the largest density ever recorded in the world for the species. Sex ratio was 1:1 and seahorses were reproductively active. We observed three juveniles. The mean length recorded was 8.9 ± 1.64 cm. The population structure was similar to others populations studied throughout the Brazilian coast.     

The organs of prey capture and digestion in the miniature predatory bivalve Spheniopsis brasiliensis (Anomalodesmata: Cuspidarioidea: Spheniopsidae) expose a novel life-history trait

Spheniopsis brasiliensis, from depths of 17–148 m off the southern Atlantic coast of Brazil, is a predator of epipsammic micro-crustaceans which it sucks into the infra-septal chamber using a raptorial inhalant siphon and internally generated hydrostatic suction forces. Prey items, which include ostracods, are thought to be pushed into the funnel-shaped mouth using the foot. The stomach is capacious with a short style sac conjoined briefly with the mid gut and possessing a stubby crystalline style. Internal stomach architecture is simplified, with no identifiable sorting areas (unlike other cuspidarioids) and lined virtually completely by a gastric shield. The exoskeletal remains of digested prey are held in the posterior end of the stomach and not in a specialised waste storage pouch as in the con-familial Grippina coronata. The mid gut, hind gut and rectum are all extremely narrow and, thus, only the smallest of faeces can be accommodated and transmitted for anal discharge. Spheniopsis brasiliensis, like G. coronata is a self-fertilising simultaneous hermaphrodite with encapsulated lecithotrophic eggs brooded internally. Both taxa are thus ovovivaporous. It is also believed that both taxa are univoltine so that larvae and the exoskeletal prey remains are all released post mortem. Cuspidariids are generally regarded as dioecious but, recently, Cardiomya costellata has been shown to be a non-brooding simultaneous hermaphrodite. The distinguishing characters between cuspidariids and spheniopsids thus appear to be their differing reproductive strategies and life history traits.     

Early microbiota,antibiotics and health

The colonization of the neonatal digestive tract provides a microbial stimulus required for an adequate maturation towards the physiological homeostasis of the host. This colonization, which is affected by several factors, begins with facultative anaerobes and continues with anaerobic genera. Accumulating evidence underlines the key role of the early neonatal period for this microbiota-induced maturation, being a key determinant factor for later health. Therefore, understanding the factors that determine the establishment of the microbiota in the infant is of critical importance. Exposure to antibiotics, either prenatally or postnatally, is common in early life mainly due to the use of intrapartum prophylaxis or to the administration of antibiotics in C-section deliveries. However, we are still far from understanding the impact of early antibiotics and their long-term effects. Increased risk of non-communicable diseases, such as allergies or obesity, has been observed in individuals exposed to antibiotics during early infancy. Moreover, the impact of antibiotics on the establishment of the infant gut resistome, and on the role of the microbiota as a reservoir of resistance genes, should be evaluated in the context of the problems associated with the increasing number of antibiotic resistant pathogenic strains. In this article, we review and discuss the above-mentioned issues with the aim of encouraging debate on the actions needed for understanding the impact of early life antibiotics upon human microbiota and health and for developing strategies aimed at minimizing this impact.     

Intrusion triggering of the 2010 Eyjafjallajökull explosive eruption

Gradual inflation of magma chambers often precedes eruptions at highly active volcanoes. During such eruptions, rapid deflation occurs as magma flows out and pressure is reduced. Less is known about the deformation style at moderately active volcanoes, such as Eyjafjallaj?kull, Iceland, where an explosive summit eruption of trachyandesite beginning on 14 April 2010 caused exceptional disruption to air traffic, closing airspace over much of Europe for days. This eruption was preceded by an effusive flank eruption of basalt from 20 March to 12 April 2010. The 2010 eruptions are the culmination of 18?years of intermittent volcanic unrest. Here we show that deformation associated with the eruptions was unusual because it did not relate to pressure changes within a single magma chamber. Deformation was rapid before the first eruption (>5?mm per day after 4 March), but negligible during it. Lack of distinct co-eruptive deflation indicates that the net volume of magma drained from shallow depth during this eruption was small; rather, magma flowed from considerable depth. Before the eruption, a ～0.05?km(3) magmatic intrusion grew over a period of three months, in a temporally and spatially complex manner, as revealed by GPS (Global Positioning System) geodetic measurements and interferometric analysis of satellite radar images. The second eruption occurred within the ice-capped caldera of the volcano, with explosivity amplified by magma-ice interaction. Gradual contraction of a source, distinct from the pre-eruptive inflation sources, is evident from geodetic data. Eyjafjallaj?kull's behaviour can be attributed to its off-rift setting with a 'cold' subsurface structure and limited magma at shallow depth, as may be typical for moderately active volcanoes. Clear signs of volcanic unrest signals over years to weeks may indicate reawakening of such volcanoes, whereas immediate short-term eruption precursors may be subtle and difficult to detect.     

Creation and diagnosis of a solid-density plasma with an X-ray free-electron laser

Matter with a high energy density (>10(5)?joules per cm(3)) is prevalent throughout the Universe, being present in all types of stars and towards the centre of the giant planets; it is also relevant for inertial confinement fusion. Its thermodynamic and transport properties are challenging to measure, requiring the creation of sufficiently long-lived samples at homogeneous temperatures and densities. With the advent of the Linac Coherent Light Source (LCLS) X-ray laser, high-intensity radiation (>10(17)?watts per cm(2), previously the domain of optical lasers) can be produced at X-ray wavelengths. The interaction of single atoms with such intense X-rays has recently been investigated. An understanding of the contrasting case of intense X-ray interaction with dense systems is important from a fundamental viewpoint and for applications. Here we report the experimental creation of a solid-density plasma at temperatures in excess of 10(6) kelvin on inertial-confinement timescales using an X-ray free-electron laser. We discuss the pertinent physics of the intense X-ray-matter interactions, and illustrate the importance of electron-ion collisions. Detailed simulations of the interaction process conducted with a radiative-collisional code show good qualitative agreement with the experimental results. We obtain insights into the evolution of the charge state distribution of the system, the electron density and temperature, and the timescales of collisional processes. Our results should inform future high-intensity X-ray experiments involving dense samples, such as X-ray diffractive imaging of biological systems, material science investigations, and the study of matter in extreme conditions.