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1.
Ecol Evol ; 10(11): 4531-4561, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32551042

RESUMO

Reproductive mode, ancestry, and climate are hypothesized to determine body size variation in reptiles but their effects have rarely been estimated simultaneously, especially at the intraspecific level. The common lizard (Zootoca vivipara) occupies almost the entire Northern Eurasia and includes viviparous and oviparous lineages, thus representing an excellent model for such studies. Using body length data for >10,000 individuals from 72 geographically distinct populations over the species' range, we analyzed how sex-specific adult body size and sexual size dimorphism (SSD) is associated with reproductive mode, lineage identity, and several climatic variables. Variation in male size was low and poorly explained by our predictors. In contrast, female size and SSD varied considerably, demonstrating significant effects of reproductive mode and particularly seasonality. Populations of the western oviparous lineage (northern Spain, south-western France) exhibited a smaller female size and less female-biased SSD than those of the western viviparous (France to Eastern Europe) and the eastern viviparous (Eastern Europe to Far East) lineages; this pattern persisted even after controlling for climatic effects. The phenotypic response to seasonality was complex: across the lineages, as well as within the eastern viviparous lineage, female size and SSD increase with increasing seasonality, whereas the western viviparous lineage followed the opposing trends. Altogether, viviparous populations seem to follow a saw-tooth geographic cline, which might reflect the nonmonotonic relationship of body size at maturity in females with the length of activity season. This relationship is predicted to arise in perennial ectotherms as a response to environmental constraints caused by seasonality of growth and reproduction. The SSD allometry followed the converse of Rensch's rule, a rare pattern for amniotes. Our results provide the first evidence of opposing body size-climate relationships in intraspecific units.

2.
Zootaxa ; 4695(5): zootaxa.4695.5.2, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31719333

RESUMO

We present information on primary type specimens for 13,282 species and subspecies of reptiles compiled in the Reptile Database, that is, holotypes, neotypes, lectotypes, and syntypes. These represent 99.4% of all 13,361 currently recognized taxa (11,050 species and 2311 subspecies). Type specimens of 653 taxa (4.9%) are either lost or not located, were never designated, or we did not find any information about them. 51 species are based on iconotypes. To map all types to physical collections we have consolidated all synonymous and ambiguous collection acronyms into an unambiguous list of 364 collections holding these primary types. The 10 largest collections possess more than 50% of all (primary) reptile types, the 36 largest collections possess more than 10,000 types and the largest 73 collections possess over 90% of all types. Of the 364 collections, 107 hold type specimens of only 1 species or subspecies. Dozens of types are still in private collections. In order to increase their utility, we recommend that the description of type specimens be supplemented with data from high-resolution images and CT-scans, and clear links to tissue samples and DNA sequence data (when available). We request members of the herpetological community provide us with any missing type information to complete the list.


Assuntos
Répteis , Animais , Bases de Dados Factuais
3.
Zootaxa ; 4555(3): 331-345, 2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30790920

RESUMO

Based on three adult specimens, viz. two males and a female that form the type series, a new species of blind or worm-like lizards is described from Pulau (= Island) Manado Tua, a little volcanic island located off the northern tip of the Minahassa Peninsula of Sulawesi, Indonesia. Dibamus manadotuaensis sp. nov. differs from all congeneric species in the following unique combination of characters: maximum snout-vent length 135 mm; tail length up to 14.2 mm (i.e., 12-13% of SVL); labial and nasal sutures present and complete; four (three) postoculars; four to six scales on posterior edge of infralabial; 26-28 midbody scale rows; 30-33 transverse scale rows posterior to head; 25 transverse scale rows anterior to vent; 218-232 ventral scales; 39 subcaudal scales; relative size of frontal to frontonasal 0.68-0.73; relative size of interparietal to surrounding scales 0.67-1.43; 132-135 presacral and 21-24 postsacral vertebrae. Morphologically, D. manadotuaensis is most similar to D. celebensis, which occurs on mainland Sulawesi.Dibamus manadotuaensis sp. nov. represents the twenty-fourth species of Dibamus and the third species of this genus recorded from the Sulawesi region. At the same time, it is the only squamate species considered endemic for the islands of the Bunaken Marine National Park, to which Manado Tua belongs.


Assuntos
Lagartos , Distribuição Animal , Estruturas Animais , Animais , Tamanho Corporal , Feminino , Indonésia , Ilhas , Masculino
4.
Zootaxa ; 4471(1): 137-153, 2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-30313421

RESUMO

Based on morphological characteristics, two subspecies of the Transcaucasian rat snake (Zamenis hohenackeri) are currently recognized, namely Z. h. tauricus and Z. h. hohenackeri. Both subspecies are repeatedly considered to be conspecific colour morphs, or have even been confused with Z. situla. Although, few studies involved the Transcaucasian rat snake in a phylogenetic approach, none has so far led to any taxonomic changes. We assessed the intraspecific morphological variation and phylogeographic relationships among specimens from different locations across its updated distribution. Our molecular (1191 bp mtDNA, 565 bp nuDNA) and morphological data provide sufficient evidence to support three distinct lineages within the Z. hohenackeri complex with a different arrangement compared to a previous study. These represent the subspecies Z. h. hohenackeri, Z. h. tauricus, and a lineage from southwestern Turkey which is described as a new subspecies. Aspects of historical biogeography and conservation status are briefly discussed.


Assuntos
Colubridae , Filogenia , Animais , DNA Mitocondrial , Filogeografia , Turquia
5.
Zootaxa ; 4385(1): 1-101, 2018 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-29689914

RESUMO

A checklist of the amphibians and reptiles of 35 localities situated in the northern Peruvian dry forest valley of the Marañón River and its tributaries, containing 14 species of amphibians and 54 species of reptiles, is provided from data collected between July 2005 and April 2014 during several herpetological surveys and from the literature. Detailed accounts are given for each collected species containing morphometric and scalation data, information on natural history, comments regarding their distribution, the conservation status and key literature. Eleven new species were discovered and described during the survey period. At least five additional taxa might also represent new species but more field work and data collection are necessary to determine their status. For two snake species we provide the first country record and for 23 further species new departamental records are provided.


Assuntos
Anfíbios , Biodiversidade , Répteis , Animais , Florestas , Peru , Rios
6.
Sci Rep ; 7(1): 7378, 2017 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-28785033

RESUMO

Recent studies found major conflicts between traditional taxonomy and genetic differentiation of grass snakes and identified previously unknown secondary contact zones. Until now, little is known about gene flow across these contact zones. Using two mitochondrial markers and 13 microsatellite loci, we examined two contact zones. One, largely corresponding to the Rhine region, involves the western subspecies Natrix natrix helvetica and the eastern subspecies N. n. natrix, whereas in the other, more easterly, contact zone two lineages meet that are currently identified with N. n. natrix and N. n. persa. This second contact zone runs across Central Europe to the southern Balkans. Our analyses reveal that the western contact zone is narrow, with parapatrically distributed mitochondrial lineages and limited, largely unidirectional nuclear gene flow. In contrast, the eastern contact zone is very wide, with massive nuclear admixture and broadly overlapping mitochondrial lineages. In combination with additional lines of evidence (morphology, phylogeny, divergence times), we conclude that these differences reflect different stages in the speciation process and that Natrix helvetica should be regarded as a distinct species. We suggest a nomenclatural framework for presently recognized grass snake taxa and highlight the need for reconciling the conflicts between genetics and taxonomy.


Assuntos
Hibridização Genética , Serpentes/classificação , Serpentes/genética , Animais , DNA Mitocondrial , Europa (Continente) , Geografia , Haplótipos , Repetições de Microssatélites , Filogenia , Dinâmica Populacional , Análise de Sequência de DNA
7.
J Exp Biol ; 219(Pt 22): 3597-3604, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27852763

RESUMO

The sandfish lizard, Scincus scincus (Squamata: Scincidae), spends nearly its whole life in aeolian sand and only comes to the surface for foraging, defecating and mating. It is not yet understood how the animal can respire without sand particles entering its respiratory organs when buried under thick layers of sand. In this work, we integrated biological studies, computational calculations and physical experiments to understand this phenomenon. We present a 3D model of the upper respiratory system based on a detailed histological analysis. A 3D-printed version of this model was used in combination with characteristic ventilation patterns for computational calculations and fluid mechanics experiments. By calculating the velocity field, we identified a sharp decrease in velocity in the anterior part of the nasal cavity where mucus and cilia are present. The experiments with the 3D-printed model validate the calculations: particles, if present, were found only in the same area as suggested by the calculations. We postulate that the sandfish has an aerodynamic filtering system; more specifically, that the characteristic morphology of the respiratory channel coupled with specific ventilation patterns prevent particles from entering the lungs.


Assuntos
Adaptação Fisiológica , Lagartos/fisiologia , Pulmão/fisiologia , Solo , Animais , Clima Desértico , Expiração/fisiologia , Hidrodinâmica , Imageamento Tridimensional , Inalação/fisiologia , Pulmão/anatomia & histologia , Modelos Anatômicos , Volume de Ventilação Pulmonar/fisiologia
8.
Zootaxa ; 4153(1): 1-192, 2016 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-27615821

RESUMO

We analysed scale morphology and micro-structure from five different body regions using scanning electron microscopy (SEM) across all nine recognized subgenera of the monitor lizard genus Varanus including 41 different species investigated. As far as we are aware, this qualitative visual technique was applied by us for the first time to most monitor lizard species and probably also to the primary outgroup and sister species Lanthanotus borneensis. A comprehensive list of 20 scalation characters each with up to seven corresponding character states was established and defined for the five body regions sampled. For the phylogenetic approach, parsimony analyses of the resulting morphological data matrix as well as Bremer and bootstrap support calculations were performed with the software TNT. Our results demonstrate that a variety of micro-ornamentations (i.e., ultra- or micro-dermatoglyphics) as seen in various squamate groups is hardly present in monitor lizards. In several species from six out of nine subgenera, however, we found a honeycomb-shaped micro-structure of foveate polygons. Two further samples of Euprepiosaurus Fitzinger, 1843 exhibit each another unique microscopic structure on the scale surface. Notably, the majority of species showing the honeycombed ultra-structure inhabit arid habitats in Australia, Africa and the Middle East. Therefore, it can be inferred that this microscopic scalation feature, which has also been identified in other desert dwelling lizard species, is taxonomically and ecologically correlated with a xeric habitat type in varanids, too. In addition, the systematic affiliation of V. spinulosus, an endemic monitor lizard species from the Solomon Islands with an extraordinary scale shape, is discussed in the light of current hypotheses about its phylogenetic position within the Varanidae. Due to its unique scalation characteristics, in combination with other morphological evidence, a new monotypic subgenus, Solomonsaurus subgen. nov., is erected for this enigmatic monitor lizard species. Furthermore, we propose a taxonomic splitting of the morphologically and ecologically heterogeneous subgenus Euprepiosaurus comprising the Pacific or mangrove and the tree monitor lizards, respectively, again based on the SEM data. Thus, for the members of the highly arboreal V. prasinus species group erection of a new subgenus, Hapturosaurus subgen. nov., is justified based on the autapomorphic scale shape in concert with further morphological, phylogenetic and ecological evidence. In addition, V. reisingeri originally described as a distinct species is considered conspecific with the wide-spread V. prasinus due to joint synapormorphic features in the ventral scale micro-structure. Consequently, V. prasinus is (again) rendered polytypic with the taxon reisingeri being assigned subspecies status here.        In conclusion, the established scalation characters allow discrimination of single species even among closely-related Varanus species, such as the members of the V. indicus species group. Together with a recently published identification key for Southeast Asian monitor lizards based on macroscopic phenotypic characters (Koch et al. 2013), the SEM-pictures of the present study may serve as additional references for the microscopic identification of CITES-relevant monitor lizard skins and products, respectively.


Assuntos
Lagartos/anatomia & histologia , Lagartos/classificação , África , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Austrália , Tamanho Corporal , Conservação dos Recursos Naturais , Ecossistema , Feminino , Lagartos/genética , Lagartos/crescimento & desenvolvimento , Masculino , Oriente Médio , Tamanho do Órgão , Filogenia
9.
Zootaxa ; 4093(1): 41-63, 2016 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-27394480

RESUMO

A new species of viperine viperid snake is described, Bitis harenna sp. nov. The new species is a member of the subgenus Macrocerastes based on it having three scales separating the nasal and rostral shields, and on the combination of 'divisions' of dorsal scale rows on the upper flanks and 'fusions' of rows on the lower flanks. Bitis harenna sp. nov. is distinguished from other members of the subgenus by its unique colour pattern, posterior parietal flange on the lateral wall of the braincase, and possibly by differences in scalation and head proportions. Only a single museum specimen is known, a female collected from 'Dodola' in Ethiopia probably in the late 1960s and previously identified as a possibly unusually coloured and patterned B. parviocula. A live, presumably male, specimen very closely resembling the holotype of Bitis harenna sp. nov. was photographed on the Harenna escarpment of the Bale Mountains National Park, Ethiopia in 2013, providing secure occurrence data and evidence that the holotype is not a uniquely aberrant specimen. A revised key to the species of Bitis in Ethiopia is presented. Aspects of body scalation are compared among species of the subgenus Macrocerastes and between species of Macrocerastes and Bitis, and several systematic characters are highlighted and clarified.


Assuntos
Viperidae/anatomia & histologia , Viperidae/classificação , Distribuição Animal , Animais , Etiópia , Feminino , Masculino , Especificidade da Espécie , Viperidae/fisiologia
10.
Arthritis Res Ther ; 18: 53, 2016 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26912229

RESUMO

BACKGROUND: Rheumatoid arthritis is characterised by progressive joint destruction and loss of periarticular bone mass. Hand bone loss (HBL) has therefore been proposed as an outcome measure for treatment efficacy. A definition of increased HBL adjusted for age- and sex-related bone loss is lacking. In this study, we aimed to: 1) establish reference values for normal hand bone mass (bone mineral density measured by digital x-ray radiogrammetry (DXR-BMD)); and 2) examine whether HBL is normalised in rheumatoid arthritis patients during treatment with tumour necrosis factor alpha inhibitors (TNFI). METHODS: DXR-BMD was measured from hand x-rays in a reference cohort (1485 men/2541 women) without arthritis randomly selected from an urban Danish population. Sex- and age-related HBL/year was estimated. DXR-BMD was measured in rheumatoid arthritis patients (n = 350: at start of TNFI, and ~2 years after TNFI start), of which 135 patients had three x-rays (~2 years prior to TNFI, at start of TNFI, and ~2 years after TNFI start). Individual HBL/year prior to and during TNFI was calculated and compared to reference values. RESULTS: Estimated HBL/year varied strongly with age and sex. Compared to the reference values, 75 % of 135 patients had increased HBL prior to TNFI treatment and 59 % had increased HBL during TNFI treatment (p = 0.17, Chi-squared). In 38 % (38/101) of patients with increased HBL, HBL was normalised during TNFI treatment, whereas 47 % (16/34) of patients with normal HBL prior to TNFI had increased HBL during TNFI treatment. In the 350 patients, increased HBL during TNFI was associated with time-averaged 28-joint disease activity score (odds ratio 1.69 (95 % Confidence Interval 1.34-2.15)/unit increase, p < 0.001), and patients in time-averaged remission had lower HBL than patients without remission (0.0032 vs. 0.0058 g/cm(2)/year; p < 0.001, Mann-Whitney). CONCLUSIONS: We established age- and sex-specific reference values for DXR-BMD in a large cohort without arthritis. HBL was increased in the majority of rheumatoid arthritis patients initiating TNFI in clinical practice, and only normalised in a minority during TNFI.


Assuntos
Artrite Reumatoide/diagnóstico por imagem , Densidade Óssea , Ossos da Mão/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Dinamarca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Sistema de Registros , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto Jovem
11.
Zootaxa ; 4039(1): 129-44, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26624470

RESUMO

The generic assignment of the draconine lizard Gonocephalus robinsonii from the highlands of West-Malaysia has been uncertain since the original description. Here we present a study based on morphology, previously published karyotype data and molecular phylogenetics using 16S rRNA sequences to evaluate the systematic status of G. robinsonii. As a result we describe Malayodracon gen. nov. to accommodate the species.


Assuntos
Lagartos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Feminino , Lagartos/anatomia & histologia , Lagartos/genética , Lagartos/crescimento & desenvolvimento , Malásia , Masculino , Tamanho do Órgão , Filogenia , RNA Ribossômico 16S/genética
12.
Zootaxa ; 3964(2): 228-44, 2015 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-26249433

RESUMO

Three new blind snake species of the genus Epictia are described based on material collected in the Peruvian Regions Amazonas, Cajamarca and La Libertad. All three species are well differentiated from all congeners based on characteristics of their morphology and coloration. They share 10 scale rows around the middle of the tail and possess two supralabials with the anterior one in broad contact with the supraocular. Epictia septemlineata sp. nov. has 16 subcaudal scales, 257 mid-dorsal scale rows, a yellowish-white rostral, and a black terminal spine. Epictia vanwallachi sp. nov. exhibits 16 subcaudals, 188 mid-dorsal scale rows, a grayish-brown rostral, and a yellow terminal spine. Epictia antoniogarciai sp. nov. features 14-18 subcaudals, 195-208 mid-dorsal scale rows, a bright yellow or yellowish-white rostral, and the terminal spine and terminal portion of the tail yellow. All three species were collected in the interandean dry forest valleys of the Marañón River and its tributaries. This region is an area of endemism and warrants further attention from systematic and conservation biologists.


Assuntos
Serpentes/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Ecossistema , Feminino , Florestas , Masculino , Tamanho do Órgão , Peru , Serpentes/anatomia & histologia , Serpentes/crescimento & desenvolvimento
13.
J Morphol ; 276(2): 167-84, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25327894

RESUMO

Chameleons (Chamaeleonidae) feature many adaptations to their arboreal lifestyle, including zygodactylous feet, a prehensile tail, and epidermal microstructures. In arboreal tree chameleons, the substrate-contacting site of the feet and tail is covered by microscopic hair-like structures (setae) of 6-20 µm length. Their friction enhancing function has been shown in recent studies. Leaf chameleons and one representative of the tree chameleons (Chamaeleo namaquensis) secondarily have become ground-dwelling. Because leaf chameleons are paraphyletic, one could expect that in the three leaf chameleon genera Brookesia, Rhampholeon, and Rieppeleon and the tree chameleon Ch. namaquensis, epidermis has adapted independently to terrestrial locomotion. Using scanning electron microscopy, we investigated the substrate-contacting surfaces of the feet (subdigital) of 17 leaf chameleon species and five tree chameleon species that have not yet been examined. Additionally, surfaces not involved in locomotion, the flanks (dorsolateral), and scale interstices, were examined. Although the subdigital microstructures in leaf chameleons are more diverse than in tree chameleons, we found some features across the genera. The subdigital microornamentation of Rhampholeon spinosus consists of long thin setae and spines, comparable to those of tree chameleons. All other Rhampholeon species have spines or short but broad setae. Rh. spectrum had tooth-like structures instead of setae. Subdigital scales of Brookesia have either thorns or conical scale-tops in the center and feature honeycomb microstructures. In Rieppeleon, subdigital scales have a thorn. Scale surfaces are covered by honeycombs and short hair-like structures (spines). As subdigital scales with a thorn in the center and honeycomb microstructures were also found in the terrestrial tree chameleon Ch. namaquensis, one can assume that this geometry is a convergent adaptation to terrestrial locomotion. Despite the great number of genus-specific traits, the convergent evolution of honey-comb structures in Brookesia, Rieppeleon, and Ch. namaquensis and the high variability of spines and setae in Rhampholeon suggests a rapid adaptation of subdigital microornamentation in Chamaeleonidae.


Assuntos
Evolução Biológica , Epiderme/ultraestrutura , Lagartos/anatomia & histologia , Adaptação Biológica , Animais , Feminino , Fricção , Lagartos/classificação , Lagartos/fisiologia , Locomoção , Masculino , Microscopia Eletrônica de Varredura , Filogenia , Folhas de Planta , Sensilas/ultraestrutura , Especificidade da Espécie
14.
J Rheumatol ; 41(12): 2352-60, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25274894

RESUMO

OBJECTIVE: To investigate baseline characteristics associated with radiographic progression and the effect of disease activity, drug, switching, and withdrawal on radiographic progression in tumor necrosis factor (TNF) inhibitor-naive patients with rheumatoid arthritis (RA) followed for about 2 years after anti-TNF initiation in clinical practice. METHODS: DANBIO-registered patients with RA who had available radiographs (anti-TNF initiation and ∼2 yrs followup) were included. Radiographs were scored, blinded to chronology with the Sharp/van der Heijde method and linked with DANBIO data. Baseline characteristics were investigated with univariate regression and significant variables included in a multivariable logistic regression analysis with ± radiographic progression [Δ total Sharp score (TSS) > 0] as dependent variable. Effect of time-averaged C-reactive protein (CRP), 28-joint Disease Activity Score with CRP (DAS28-CRP), and treatment status at followup were investigated with univariate regression analysis. RESULTS: The study included 930 patients. They were 75% women, 79% positive for IgM-rheumatoid factor (IgM-RF), median age was 57 yrs (range 19-88), disease duration 9 yrs (1-59), DAS28-CRP 5.0 (1.4-7.8), TSS median 15 [3-45 interquartile range (IQR)] and mean 31 (SD 40). Patients started treatment with infliximab (59%), etanercept (18%), or adalimumab (23%). At followup (median 526 days, IQR 392-735), 61% were treated with the initial anti-TNF, 29% had switched TNF inhibitor, and 10% had withdrawn. Twenty-seven percent of patients had progressed radiographically. ΔTSS was median 0.0 [0.0-0.5 IQR/mean 0.6 (SD 2.4)] units/year. Higher TSS, older age, positive IgM-RF, and concomitant prednisolone at baseline were associated with radiographic progression. Time-averaged DAS28-CRP and time-averaged CRP, but not type of TNF inhibitor, were associated with radiographic progression. Patients who stopped/switched during followup progressed more than patients who continued treatment. CONCLUSION: High TSS, older age, IgM-RF positivity, and concomitant prednisolone were associated with radiographic progression during 2 years of followup of 930 anti-TNF-treated patients with RA in clinical practice. High disease activity and switching/stopping anti-TNF treatment were associated with radiographic progression.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/tratamento farmacológico , Proteína C-Reativa/metabolismo , Progressão da Doença , Fator Reumatoide/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adalimumab , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Artrite Reumatoide/metabolismo , Dinamarca , Etanercepte , Feminino , Seguimentos , Humanos , Imunoglobulina G/uso terapêutico , Infliximab , Masculino , Pessoa de Meia-Idade , Radiografia , Receptores do Fator de Necrose Tumoral/uso terapêutico , Sistema de Registros , Análise de Regressão , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
15.
PLoS One ; 9(9): e108650, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25251436

RESUMO

The thermophilous giant centipede Scolopendra cingulata is a voracious terrestrial predator, which uses its modified first leg pair and potent venom to capture prey. The highly variable species is the most common of the genus in Europe, occurring from Portugal in the west to Iran in the east. The northernmost occurrences are in Hungary and Romania, where it abides in small isolated fringe populations. We report the rediscovery of an isolated Austrian population of Scolopendra cingulata with the first explicit specimen records for more than 80 years and provide insights into the evolutionary history of the northernmost populations utilizing fragments of two mitochondrial genes, COI and 16S, comprising 1,155 base pairs. We test the previously proposed hypothesis of a speciation by distance scenario, which argued for a simple range expansion of the species from the southeast, via Romania, Hungary and finally to Austria, based on a comprehensive taxon sampling from seven countries, including the first European mainland samples. We argue that more complex patterns must have shaped the current distribution of S. cingulata and that the Austrian population should be viewed as an important biogeographical relict in a possible microrefugium. The unique haplotype of the Austrian population could constitute an important part of the species genetic diversity and we hope that this discovery will initiate protective measures not only for S. cingulata, but also for its habitat, since microrefugia are likely to host further rare thermophilous species. Furthermore, we take advantage of the unprecedented sampling to provide the first basic insights into the suitability of the COI fragment as a species identifying barcode within the centipede genus Scolopendra.


Assuntos
Artrópodes/classificação , Evolução Biológica , Fósseis , Animais , Artrópodes/genética , Dados de Sequência Molecular
16.
Mol Phylogenet Evol ; 79: 215-30, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24973715

RESUMO

Africa is renowned for its biodiversity and endemicity, yet little is known about the factors shaping them across the continent. African Agama lizards (45 species) have a pan-continental distribution, making them an ideal model for investigating biogeography. Many species have evolved conspicuous sexually dimorphic traits, including extravagant breeding coloration in adult males, large adult male body sizes, and variability in social systems among colorful versus drab species. We present a comprehensive time-calibrated species tree for Agama, and their close relatives, using a hybrid phylogenetic-phylogenomic approach that combines traditional Sanger sequence data from five loci for 57 species (146 samples) with anchored phylogenomic data from 215 nuclear genes for 23 species. The Sanger data are analyzed using coalescent-based species tree inference using (*)BEAST, and the resulting posterior distribution of species trees is attenuated using the phylogenomic tree as a backbone constraint. The result is a time-calibrated species tree for Agama that includes 95% of all species, multiple samples for most species, strong support for the major clades, and strong support for most of the initial divergence events. Diversification within Agama began approximately 23 million years ago (Ma), and separate radiations in Southern, East, West, and Northern Africa have been diversifying for >10Myr. A suite of traits (morphological, coloration, and sociality) are tightly correlated and show a strong signal of high morphological disparity within clades, whereby the subsequent evolution of convergent phenotypes has accompanied diversification into new biogeographic areas.


Assuntos
Evolução Biológica , Lagartos/classificação , Filogenia , África , Animais , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Funções Verossimilhança , Lagartos/genética , Modelos Genéticos , Dados de Sequência Molecular , Filogeografia , Análise de Sequência de DNA
17.
PLoS One ; 8(12): e80563, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24324611

RESUMO

While traditionally species recognition has been based solely on morphological differences either typological or quantitative, several newly developed methods can be used for a more objective and integrative approach on species delimitation. This may be especially relevant when dealing with cryptic species or species complexes, where high overall resemblance between species is coupled with comparatively high morphological variation within populations. Rock lizards, genus Darevskia, are such an example, as many of its members offer few diagnostic morphological features. Herein, we use a combination of genetic, morphological and ecological criteria to delimit cryptic species within two species complexes, D. chlorogaster and D. defilippii, both distributed in northern Iran. Our analyses are based on molecular information from two nuclear and two mitochondrial genes, morphological data (15 morphometric, 16 meristic and four categorical characters) and eleven newly calculated spatial environmental predictors. The phylogeny inferred for Darevskia confirmed monophyly of each species complex, with each of them comprising several highly divergent clades, especially when compared to other congeners. We identified seven candidate species within each complex, of which three and four species were supported by Bayesian species delimitation within D. chlorogaster and D. defilippii, respectively. Trained with genetically determined clades, Ecological Niche Modeling provided additional support for these cryptic species. Especially those within the D. defilippii-complex exhibit well-differentiated niches. Due to overall morphological resemblance, in a first approach PCA with mixed variables only showed the separation between the two complexes. However, MANCOVA and subsequent Discriminant Analysis performed separately for both complexes allowed for distinction of the species when sample size was large enough, namely within the D. chlorogaster-complex. In conclusion, the results support four new species, which are described herein.


Assuntos
Genes Mitocondriais , Especiação Genética , Lagartos/classificação , Filogenia , Distribuição Animal , Animais , Teorema de Bayes , Núcleo Celular/química , Núcleo Celular/genética , Feminino , Irã (Geográfico) , Lagartos/genética , Masculino , Filogeografia , Análise de Sequência de DNA , Especificidade da Espécie
18.
Naturwissenschaften ; 100(11): 997-1006, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24113831

RESUMO

Snakes are a very speciose group of squamates that adapted to various habitats and ecological niches. Their ecological diversity is of particular interest and functional demands associated with their various styles of locomotion are expected to result in anatomical specializations. In order to explore the potential adaptation of snakes to their environment we here analyze variation in vertebral structure at the microanatomical level in species with different locomotor adaptations. Vertebrae, being a major element of the snake body, are expected to display adaptations to the physical constraints associated with the different locomotor modes and environments. Our results revealed a rather homogenous vertebral microanatomy in contrast to what has been observed for other squamates and amniotes more generally. We here suggest that the near-absence of microanatomical specializations in snake vertebrae might be correlated to their rather homogeneous overall morphology and reduced range of morphological diversity, as compared to lizards. Thus, snakes appear to retain a generalist inner morphology that allows them to move efficiently in different environments. Only a few ecologically highly specialized taxa appear to display some microanatomical specializations that remain to be studied in greater detail.


Assuntos
Ecossistema , Serpentes/anatomia & histologia , Coluna Vertebral/anatomia & histologia , Animais , Serpentes/classificação , Especificidade da Espécie
19.
Zootaxa ; 3702: 233-46, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26146721

RESUMO

We describe a new species of the genus Oligodon from the lowland forests of Cat Tien National Park, Dong Nai Province, in southern Vietnam. Oligodon cattienensis sp. nov. is distinguished from the remaining Southeast Asian kukri snakes by the combination of the following characters: medium-sized, deeply forked hemipenes without spines, 17-17-15 dorsal scale rows, nasal entire, 2 small postoculars, almost equal in size, 167-178 ventrals, 31-35 subcaudals, 24-35 + 5 large dark-edged vertebral blotches in combination with a yellow-orange or red vertebral stripe between blotches, head pattern including ocular band, temporal bands and elongated chevron, ventrals pink or whitish (reddish in juveniles) in life, some bearing a quadrangular dark blotch on each lateral side, or ventrals being entirely dark. Based on the hemipenial morphology the new species is assigned to the Oligodon cyclurus species group. A comparison table for all Indochinese Oligodon is provided.


Assuntos
Colubridae/anatomia & histologia , Colubridae/classificação , Animais , Feminino , Masculino , Vietnã
20.
Zootaxa ; 3599: 246-60, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24613873

RESUMO

We describe a new species of the agamid genus Calotes Cuvier, 1817 from southern Vietnam, which is most similar to Calotes mystaceus Duméril & Bibron, 1837, but can be distinguished from the latter and its other congeners by genetic and morphological differences. We discuss the current distribution of the new species and its sister species C. mystaceus in Mainland Southeast Asia.


Assuntos
Lagartos/classificação , Lagartos/genética , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Lagartos/anatomia & histologia , Masculino , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Vietnã
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