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1.
Zookeys ; 1198: 279-294, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38708379

RESUMO

A new species of Larca is described from dry habitats in a cave in central Colorado. Like other cave-dwelling species of Larca, the new species Larcabouldericasp. nov., shows relatively modest morphological adaptations, such as pale colouration and slightly elongated appendages, compared with their epigean counterparts. This species is the sixth cave-dwelling species of Larca described from North America and, like other cave-dwelling Larca in North America and Europe, tends to be distributed in more southerly regions.

2.
Water (Basel) ; 15(1): 1-20, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36798655

RESUMO

The effects of nonpoint source nutrients on estuaries can be difficult to pinpoint, with researchers often using indicator species, monitoring, and models to detect influence and change. Here, we made stable isotope measurements of nitrogen and carbon in sediment, water column particulates, primary producers, and consumers at 35 stations in the reportedly eutrophic Barnegat Bay (New Jersey) to assess N sources and processing pathways. Combined with water quality and hydrological data, our C and N isoscapes revealed four distinct geographic zones with diverging isotopic baselines, indicating variable nutrient sources and processing pathways. Overall, the carbon stable isotopes δ13C) reflected the terrestrial-marine gradient with the most depleted values in the urban and poorly flushed north of the estuary to the most enriched values in the salt marsh-dominated south. In contrast, the nitrogen stable isotope values δ15N) were most enriched near the oceanic inlets and were consistent with offshore δ15N values in particulate organic matter. Several biogeochemical processes likely alter δ15N, but the relatively lower δ15N values associated with the most urbanized area indicate that anthropogenic runoff is not a dominant N source to this area. Our findings stand in contrast to previous studies of similar estuaries, as δ15N signatures of biota in this system are inversely correlated to population density and nutrient concentrations. Further, our analyses of archival plant (Spartina sp., Phragmites australis) and shell (Geukensia demissa, Ilyanassa obsoleta) samples collected between 1880 and 2020 indicated that δ15N values have decreased over time, particularly in the consumers. Overall, we find that water quality issues appear to be most acute in the poorly flushed parts of Barnegat Bay and emphasize the important role that oceanic exchange plays in water quality and associated estuarine food webs in the lagoon.

3.
J AOAC Int ; 104(1): 49-52, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33751069

RESUMO

BACKGROUND: Grain mills, feed mills, ethanol plants, flour producers, but also mobile laboratory services need simple and reliable possibilities to analyze grain for mycotoxins during harvest in the field. OBJECTIVE: The RIDA®SMART APP is a smartphone application, which was developed together with a Lateral Flow Device as a quantitative and fast on-site/on-field tool for mycotoxin analyses. METHOD: It is a small and light device with its own power supply, very versatile, flexible and easy to use. For quantification, a lot specific calibation curve is uploaded to the RIDA®SMART APP via a QR code from the certificate of analysis. The software application in combination with a compatible smartphone, analyzes the LFD strip via a picture taken with a smartphone and quantifies the mycotoxin contamination within 4 second. Due to the possibility to use mobile networks or WIFI, there are no difficulties in the organization of the collected results. Currently, nine different android-based smartphones from various manufacturers are compatible with the RIDA®SMART APP. RESULTS: In combination with one of the compatible smartphones, the RIDA®SMART APP is able to generate results with a coefficient of variation CV ≤ 13%, even at highly varying lighting conditions. The recovery of certified reference corn samples, previously analyzed with HPLC or LC-MS/MS, shows a mean value between 91% - 119%. CONCLUSION: The RIDA®SMART APP is highly suitable for an inexpensive, quick and accurate quantitative measurement of mycotoxins in agricultural products (e.g. aflatoxins in corn). HIGHLIGHTS: To our best knowledge, the RIDA®SMART APP is the only smartphone-based method for quantitative mycotoxin analysis worldwide combined with a broader measuring range as most usual lateral flow analyzers.


Assuntos
Aplicativos Móveis , Micotoxinas , Scrapie , Animais , Cromatografia Líquida , Ovinos , Smartphone , Espectrometria de Massas em Tandem
4.
Zootaxa ; 4066(4): 451-68, 2016 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-27395846

RESUMO

A new species of the tubificine genus Limnodrilus is described and COI barcoded from Sulphur Cave and associated springs in Colorado, USA. The habitats are characterized by high sulfide concentrations. The new species, L. sulphurensis, is distinguished from all congeners by the elongate, nearly parallel teeth of chaetae in its anterior segments. It has a penis sheath resembling that of L. profundicola; consequently, museum specimens and new collections are examined here to resolve some of the taxonomic confusion surrounding that widespread, but uncommon species.


Assuntos
Oligoquetos/anatomia & histologia , Oligoquetos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Cavernas/química , Colorado , Ecossistema , Masculino , Oligoquetos/crescimento & desenvolvimento , Tamanho do Órgão , Enxofre/análise
5.
Zootaxa ; 3745: 486-90, 2013 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-25113364

RESUMO

Austrotyla stephensoni n. sp., from Colorado, is described as the first troglobiotic species of its genus, and compared to sympatric Austrotyla coloradensis (Chamberlin 1910). A key to all Austrotyla species is provided. 


Assuntos
Artrópodes/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Animais , Artrópodes/anatomia & histologia , Cavernas , Colorado , Ecossistema , Masculino
6.
PLoS One ; 5(5): e10388, 2010 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-20479884

RESUMO

BACKGROUND: Many cave-dwelling animal species display similar morphologies (troglomorphism) that have evolved convergent within and among lineages under the similar selective pressures imposed by cave habitats. Here we study such ecomorphological evolution in cave-dwelling Sclerobuninae harvestmen (Opiliones) from the western United States, providing general insights into morphological homoplasy, rates of morphological change, and the temporal context of cave evolution. METHODOLOGY/PRINCIPAL FINDINGS: We gathered DNA sequence data from three independent gene regions, and combined these data with Bayesian hypothesis testing, morphometrics analysis, study of penis morphology, and relaxed molecular clock analyses. Using multivariate morphometric analysis, we find that phylogenetically unrelated taxa have convergently evolved troglomorphism; alternative phylogenetic hypotheses involving less morphological convergence are not supported by Bayesian hypothesis testing. In one instance, this morphology is found in specimens from a high-elevation stony debris habitat, suggesting that troglomorphism can evolve in non-cave habitats. We discovered a strong positive relationship between troglomorphy index and relative divergence time, making it possible to predict taxon age from morphology. Most of our time estimates for the origin of highly-troglomorphic cave forms predate the Pleistocene. CONCLUSIONS/SIGNIFICANCE: While several regions in the eastern and central United States are well-known hotspots for cave evolution, few modern phylogenetic studies have addressed the evolution of cave-obligate species in the western United States. Our integrative studies reveal the recurrent evolution of troglomorphism in a perhaps unexpected geographic region, at surprisingly deep time depths, and in sometimes surprising habitats. Because some newly discovered troglomorphic populations represent undescribed species, our findings stress the need for further biological exploration, integrative systematic research, and conservation efforts in western US cave habitats.


Assuntos
Aracnídeos/anatomia & histologia , Evolução Biológica , Ecossistema , Animais , Aracnídeos/classificação , Teorema de Bayes , Biodiversidade , Geografia , Masculino , Noroeste dos Estados Unidos , Pênis/anatomia & histologia , Filogenia , Análise de Componente Principal , Sudoeste dos Estados Unidos , Fatores de Tempo
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