First multi-proxy record of Jurassic wildfires from Gondwana: Evidence from the Middle Jurassic of the Neuquén Basin,Argentina

Wildfires play a crucial role in recent and ancient ecosystem modeling but their detailed history on the Earth is still not well recorded or understood. The co-occurrence of charcoal and pyrolytic polycyclic aromatic hydrocarbons (PAHs) is used for the recognition of wildfires in geological record that may have implications for the analysis of the terrestrial environment, ecosystems, climate and the level of atmospheric oxygen. Here we present the first multi-proxy evidence of wildfires on the Gondwana continent during the Jurassic, based on the occurrence of charcoal and pyrolytic PAHs in the Middle Jurassic of the Neuquén Basin, Argentina. This is the first evidence of wildfire in the Aalenian, the lowest stage of the Middle Jurassic, and one of the few records of wildfires in the Bathonian. Temperature interpretations, derived from charcoal reflectance data, show that charcoals formed in low temperature surface fires that only sporadically reached the higher temperatures, possibly related to crown fires. The occurrence of charcoals in the Middle Jurassic deposits confirms recent results that the atmospheric oxygen level reached at least 15% during the Middle Jurassic times.     

Hypowaagenia? bodenbenderi (Behrendsen): A rare aspidoceratid ammonite from the Tithonian of the Neuquén Basin,Argentina

Among the ammonite collection from the Neuquén and Mendoza provinces made by G. Bodenbender, stands Aspidoceras bodenbenderi Behrendsen. This rare aspidoceratid is assigned to the lower Alternans Zone because of the associated Parodontoceras calistoides (Behrendsen), and can be most likely attributed to the recently established genus Hypowaagenia Schweigert & Schlampp.     

Brote de histoplasmosis en la provincia de Neuquén,Patagonia Argentina

BackgroundIn Argentina, there are no reports of autochthonous cases of histoplasmosis in the southern regions of the country.AimTo report a histoplasmosis outbreak in Zapala town, Province of Neuquén, Patagonia Argentina.MethodsWe evaluated the clinical and epidemiological characteristics of 5 patients involved in the outbreak. Environmental studies were conducted to determine the source of infection. The genetic profile of Histoplasma capsulatum strains isolated from the index case (IC) were compared with clinical isolates from Argentinean patients not related to the outbreak, using RAPD-PCR with primers 1281-1283.ResultsThe patients were residents of Zapala, and had not visited other geographical areas before. All patients had an influenza-like syndrome, and X-ray revealed disseminated micronodular images throughout the lung parenchyma. The IC needed specific antifungal therapy; the remaining 4 patients had mild symptoms, and did not require therapy. All of them had a good clinical outcome. Strains of H. capsulatum isolated from blood culture and lung biopsy of the IC showed a genetic profile different from other strains analyzed. The presence of the fungus in the environment was demonstrated by the detection of anti-Histoplasma antibodies in BALB/c mice inoculated with soil obtained in a culvert where workers had dug up earth after a landslide.ConclusionsThis outbreak suggests the histoplasmosis endemic area is under the 38° S parallel. Patients from Neuquén, Patagonia Argentina, with compatible symptoms of histoplasmosis should be tested, regardless of their travel or exposure history.     

First Amphilestid from South America: A Molariform from the Jurassic Ca?adón Asfalto Formation, Patagonia, Argentina

We report here the first amphilestid triconodont from the Jurassic of South America. The specimen, a single isolated molariform, was found at the Queso Rallado locality from where a growing mammalian fauna is known (including a triconodontid, two australosphenidans, and an as yet undescribed allotherian). The specimen, interpreted as a left lower tooth, presents five mesiodistally aligned, fairly symmetrical cusps, and is recognized as the type of a new taxon, Condorodon spanios. The phylogenetic analysis recovers Condorodon as a member of the clade Amphilestheria, closely related to Tendagurodon janenschi, an amphilestid triconodont from the Late Jurassic of Tanzania. Condorodon spanios is only distantly related to Argentoconodon fariasorum, the other triconodont known from Queso Rallado quarry. The phylogenetic position of Condorodon spanios points to the origin and diversification of amphilestherians during the Early Jurassic in a paleogeographical setting that allowed wide dispersion of these forms and argues, at least from the mammalian evidence, against a highly provincialized Pangaea. Some differences are however established between the filial western/eastern Gondwanan masses and their respective faunas.     

First prokaryotic biodiversity assessment using molecular techniques of an acidic river in Neuquén, Argentina

Two acidic hot springs close to the crater of Copahue Volcano (Neuquén, Argentina) are the source of the Río Agrio. The river runs several kilometres before flowing into Caviahue Lake. Along the river, temperature, iron, other metal and proton concentrations decrease gradually with distance downstream. From the source to the lake and depending on the season, pH can rise from 1.0 (or even less) to about 4.0, while temperature values decrease from 70°C to 15°C. Water samples were taken from different stations on the river selected according to their physicochemical parameters. In order to assess prokaryotic biodiversity throughout the water column, different and complementary molecular biology techniques were used, mainly in situ hybridisation and 16S rRNA gene cloning and sequencing. All microorganisms found are typical of acidic environments. Sulphur-oxidizing bacteria like Acidithiobacillus thiooxidans and Acidithiobacillus albertensis were detected in every station. Moderately thermophile iron- and sulphur-oxidizing bacteria like members of Alicyclobacillus and Sulfobacillus genera were also ubiquitous. Strict iron-oxidizing bacteria like Leptospirillum and Ferrimicrobium were present at the source of the river, but disappeared downstream where iron concentrations were much lower. Iron-oxidizing, mesophilic Ferroplasma spp. were the main archaea found. The data presented in this work represent the first molecular assessment of this rare natural acidic environment.     

Crayfish burrows from Late Jurassic–Late Cretaceous continental deposits of Patagonia: Argentina. Their palaeoecological,palaeoclimatic and palaeobiogeographical significance

The trace fossil, Loloichnus baqueroensis igen. and isp. nov., from Late Jurassic–Late Cretaceous continental deposits of Patagonia, Argentina, includes thickly lined, mostly passively-filled, and Y-branched burrows. Other important features of this ichnofossil are the inner surface texture of lining showing transversal, elongated, and adjacent grooves, and less commonly, the pelletal filling of burrows. L. baqueroensis is recorded from the Bajo Grande, Bajo Tigre, Punta del Barco, and Laguna Palacios Formations, which were deposited in different volcaniclastic environments of the Deseado Massif and San Jorge Basin geological provinces, respectively. The described burrows are found in many levels of palaeosols developed in reworked piroclastic deposits, where they are the main component of the ichnofabrics, in association with meniscate and thinly lined burrows and a diffuse and complex boxwork of small diameter burrows. Root traces are also present, and in many cases, occur inside L. baqueroensis. Considering general morphology, surface texture, filling types, palaeoenvironments in which they occur, and comparisons with extant and fossil decapod burrows, the likely trace makers of L. baqueroensis were crayfishes (Decapoda: Astacidea), probably Parastacidae. The producers of L. baqueroensis inhabited soils, where their burrows probably reached the water table, and contained roots that were used for feeding. Considering climatic preferences of extant parastacids, it is proposed a temperate climate for central Patagonia during the deposition of the studied units. The widespread presence of crayfishes during Late Jurassic–Late Cretaceous times in central Patagonia, supports the monophyletic origin of this group during the Triassic, and suggests that the present restricted geographic distribution in southern South America is a relict of a broader one.     

Heterogeneous distribution of human cystic echinococcosis after a long-term control program in Neuquén, Patagonia Argentina

The present study is the first comprehensive analysis of human cystic echinococcosis (CE) epidemiological data carried out in the province of Neuquén, Patagonia Argentina, after 34 years of uninterrupted control program. A retrospective study of all the official records of confirmed human CE cases between 1995 and 2004 was carried out. A total of 1107 cases were reported. The overall mean annual incidence (MAI) was 24.4 per 100,000 inhabitants for the total population and 9.7/100,000 in the 0-14 year group. Distribution of cases by age and sex as well as frequency of cyst locations was analysed. Children accounted for 13.3% of total cases, indicating active transmission of the disease. Territorial distribution of cases was highly heterogeneous: MAI per 100,000 ranged from 7.9 in the Metropolitan Sanitary Area to 78.4 in the western rural areas. Higher values were recorded in small communities as Pilo Lil (800/100,000). MAI showed a significant decrease from 1995 to 1999 (43.9-18.8) but remains stable from 2000 to 2004 (15.9-15.5). These results suggest that standard control measures, despite long-term implementation, are not able to produce a sustained improvement of the epidemiological status of the disease. Further studies about local transmission cycles, definite and intermediate hosts present, Echinococcus granulosus strains or cultural behaviours in small communities are required in order to adequate the control actions in Neuquén.     

Two new theropod egg sites from the Late Jurassic Lourinhã Formation,Portugal

Two new Late Jurassic (uppermost Late Kimmeridgian) dinosaur eggshell sites are described, Casal da Rola and Porto das Barcas, both near Lourinhã, central-west Portugal. Casal da Rola yields eggshells with an obliquiprismatic morphotype comparable to those from a nest with the associated fossil embryos from Paimogo, tentatively assigned to the theropod Lourinhanosaurus antunesi. The Porto das Barcas eggshells have a dendrospherulitic morphotype with a prolatocanaliculate pore system. This morphotype was also recognised in eggshells from a clutch with associated Torvosaurus embryos at the Porto das Barcas locality. A preliminary cladistic analysis of eggshell morphology suggests theropod affinities for the Casal da Rola eggs, but is unable to resolve the phylogenetic position of the Porto das Barcas eggs. The eggshells at both sites are preserved in distal flood plain mudstones and siltstones. Carbonate concretions within the deposits indicate paleosol development.     

Description of a new species of Haemogamasus (Mesostigmata, Laelapidae, Haemogamasinae) from Chubut, Río Negro and Neuquén Provinces, Argentina

A new species of Haemogamasus mites is described from Chubut, Neuquén and Río Negro Provinces, Argentina. It was collected primarily from rodents of the genus Abrothrix (65 of 77 collections): Abrothrix longipilis (63), Abrothrix olivaceus olivaceus (1) and Abrothrix olivaceus xanthorhinus (1). Additional collections were made from Geoxus valdivianus (5) and Loxdomtomys micropus (5). Possibly incidental or contaminate collections were recorded from Oligoryzomys longicaudatus (1) and Dromiciops gliroides (1). Most collections came from Río Negro Province (36), with 22 from Neuquén and 19 from Chubut. An identification key is provided to distinguish ♀s of this new species from ♀s of species from the western hemisphere, based on morphological characters.     

Shark faunas from the Late Jurassic—Early Cretaceous of northeastern Thailand

A revision of the freshwater shark fauna from the Phu Kradung Formation in NE Thailand allows the recognition of a new species of Acrodus, which represents the youngest occurrence of the genus and confirms its displacement in freshwater environments after the Toarcian. The rest of the shark fauna includes teeth of Hybodus sp., aff. Hybodus sp., hybodontid dermal denticles, Jiaodontus sp., Lonchidion sp. A, Lonchidion sp. B, Heteroptychodus cf. H. kokutensis and dorsal fin spines. The presence of Jaiodontus and of unusual hybodontid dermal denticles suggests a Jurassic age for most of the Phu Kradung Formation, whereas the presence of Heteroptychodus suggests an Early Cretaceous age for the top of the Formation. However, the age of the Phu Kradung Formation is still uncertain, with contradictory signals coming from palynology, detrital zircon thermochronology and vertebrate palaeontology. In any case, it appears that this is the oldest occurrence of the genus Heteroptychodus, and suggests a Thai origin for this genus, which may have replaced Acrodus in the Thai freshwater palaeoecosystems. Together with Acrodus, the presence of Lonchidion sp. A suggests some European affinities for the shark fauna from the Phu Kradung Formation.     

Oxfordian perisphinctid ammonites from Chacay Melehué, Argentina

A significant assemblage of Oxfordian perisphinctids was collected at Chacay Melehué, Neuquén, Argentina. It is composed of well preserved specimens belonging to the family Perisphinctidae:Perisphinctes aff.promiscuus Bukowski (Perisphinctinae),Tenuisphinctes herreroduclouxi (Leanza) (Perisphinctinae), andSubvinalesphinctes pseudokranaus n. sp. andS. prophetae (Gygi & Hillebrandt) (Vinalesphinctinae). The family Ataxioceratidae is represented byLithacosphinctes aff. janus (Choffat) (Ataxioceratinae). The subfamily VinalesphinctinaeMeléndez & Myczynski, 1987 is discussed and organized into three genera:Subvinalesphinctes Wierzbowski,Vinalesphinctes Spath andCubasphinctes Judoley & Furrazola, which seems to cover the whole of the subfamily, ranging, at least, from the lowerplicatilis to the lowerbifurcatus zones, Middle Oxfordian in Cuba, part of Mexico, Chile and Argentina. The root of the subfamily is most likelyS. pseudokranaus n. sp. The paleobiogeographic affinites are mainly Tethyan, and Tethyan-Caribbean during the Middle Oxfordian.     

New ommatids from the Late Jurassic of western Liaoning, China （Coleoptera： Archostemata）

A new genus Amblomma gen. nov. of fossil beetles is erected and can be assignedto the family Ommatidae because its two procoxal cavities are contiguous and the articulations of the abdominal ventrites are abutting. The new genus is similar to Zygadenia Handlirsch, 1906 (=Notocupes Ponomarenko, 1964), Tetraphalerus Waterhouse, 1901,Rhobdocupes Ponomarenko, 1966 and Sinocupes Lin, 1976, but can be distinguished from other genera according to the following characters: the second segment of antennae is shorterthan the third one in length; the posterior tarsi with the basal segment is obviously shorter than the three following taken together in length; the antennae reach the posterior ridge of prothroax in length, and the sides of the prothroax with serrulate margin. Four new species of the new genus are described and figured: Amblomma psilata gen. et sp. nov., Amblomma rudis gen. et sp. nov., Amblomma epicharis gen. et sp. nov., and Amblomma stabilis gen. etsp. nov. A key to species within this new genus is provided. All the specimens are collected from the Late Jurassic Yixian Formation of western Liaoning and are now housed in the College of Life Science, Capital Normal University, Beijing, China.     

Usefulness and validation of a coproantigen test for dog echinococcosis screening in the consolidation phase of hydatid control in Neuquén,Argentina

Hydatidosis is endemic in Neuquén, Patagonia, Argentina, even though sanitary authorities have been performing a control programme since 1970. At present, the programme is in consolidation phase, and dogs have being evaluated by arecoline purgation. The aims of this study were to evaluate diagnostic performance of a coproantigen (CAg) ELISA test developed “in house” and to assess CAg detection in prepatent period. We examined 8 dogs experimentally infected with Echinococcus granulosus and 403 rural dogs in an endemic area in Neuquén using CAg ELISA test and arecoline purgation. Within the experimental dog group, sensitivity and specificity of the test were 93.6% and 88.5% respectively. In rural dogs group, the overall prevalence of canine echinococcosis was 3.7% using arecoline purgation and 12.4% by the CAg test; sensitivity and specificity of the test using arecoline purge as standard were 73.3% and 89.9% respectively. Possible cross reactions in CAg test were evaluated in rural dogs: CAg was undetectable in 96.4% of the dogs infected only with taeniids non-E. granulosus, and in 90.1% of dogs infected with non-taeniid helminths. The CAg test could detect infections within prepatent period and produced negative results after worm expulsion. Our test showed adequate diagnostic performance with experimentally and naturally infected dogs, in the epidemiological situation of Neuquén. Employment of this sensitive and practical method for surveillance in the control programme in Neuquén would improve screening of canine echinococcosis by detecting infected dogs even with low burdens or within prepatent period.     

Draconyx loureiroi,a new camptosauridae (Dinosauria,Ornithopoda) from the Late Jurassic of Lourinhã, Portugal

A new ornithopod dinosaur is described here under the name of Draconyx loureiroi n. gen., n. sp. on teeth, caudal vertebrae, forelimb, hindlimb, and foot material that were found in association in the Late Jurassic-Tithonian of Lourinhã, Portugal. Draconyx is a Camptosauridae related to Camptosaurus.