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Comparative Phylogeography of Direct-Developing Frogs (Anura: Craugastoridae: Pristimantis) in the Southern Andes of Colombia  [PDF]
Juan C. García-R, Andrew J. Crawford, ángela María Mendoza, Oscar Ospina, Heiber Cardenas, Fernando Castro
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0046077
Abstract: The Andes of South America hosts perhaps the highest amphibian species diversity in the world, and a sizable component of that diversity is comprised of direct-developing frogs of the genus Pristimantis (Anura: Craugastoridae). In order to better understand the initial stages of species formation in these frogs, this study quantified local-scale spatial genetic structuring in three species of Pristimantis. DNA sequences of two mitochondrial gene fragments (16S and COI) were obtained from P. brevifrons, P. palmeri and P. jubatus at different locations in the Cordillera Occidental. We found high levels of genetic diversity in the three species, with highly structured populations (as measured by FST) in P. brevifrons and P. palmeri while P. jubatus showed panmixia. Large effective population sizes, inferred from the high levels of genetic diversity, were found in the three species and two highly divergent lineages were detected within P. jubatus and P. palmeri. Estimated divergence times among populations within P. brevifrons and P. palmeri coincide with the Pleistocene, perhaps due to similar responses to climatic cycling or recent geological history. Such insights have important implications for linking alpha and beta diversity, suggesting regional scale patterns may be associated with local scale processes in promoting differentiation among populations in the Andes.
Morphometric variation in the Tunisian green frog, Rana saharica (Anura: Ranidae)  [cached]
Nabil Amor Louw,Sarra Farjallah,Khaled Said
African Zoology , 2011,
Abstract: Rana saharicais the most widely distributed anuran in Tunisia. We examined morphological variation in 124 specimens as a function of their geographical origin, using univariate and multivariate statistics with traditional morphometrics. Our results supported the existence of three morphotypes of this species, correctly classified 84.7% of specimens, and indicated significant degrees of variation in morphometric characteristics between regions. No significant differences were found between sexes among populations. We observed an increase in body size and a decrease in body mass as a function of latitude. Specimens from the southernmost region had the smallest body size and the greatest morphometric divergence. The pattern of morphometric variation probably results from phenotypic plasticity correlated with local environmental factors.
Description of a tetraploid Tomopterna (Anura: Ranidae) from South Africa  [cached]
A. Channing,J.P. Bogart
African Zoology , 2011,
Abstract: A new tetraploid species of sand frog, genus Tomoptema, is described from the eastern Cape. On the basis of mtDNA sequences, allozymes and advertisement calls, it appears to have arisen as a hybrid between the adjacent diploid populations of T. de/a/andii and T. cryptotis. The hybridization event is estimated to have occurred 1,5 MYA. Excluding Xenopus. this is the only allotetraploid member of an advanced frog family that is known.
Assisted reproduction by using hormones in the cuban frog Osteopilus Septentrionalis. (Anura: Ranidae)  [PDF]
Trujillo Hernández J,Carballo Hondal O,Sais Guerra Y
RETEL : Revista de Toxicología en Línea , 2008,
Abstract: Assisted reproduction consists of a group of techniques for achieving reproduction or attaining eggs or embryos for different purposes and using diverse approaches (hormonal stimulation of ovulation and spermatozoids). The stimulation of the frog's ovaries, aimed at obtaining mature eggs is possible by the use of hormones in multiple combinations and with variable dosis. In Cuba, there is not previous history of results applying these techniques on the Cuban specie Osteopilus Septentrionalis ("tree frog",). The objectives of this research were obtaining eggs from this frog under laboratory conditions and determining the most recommended protocol for applying the assisted reproduction to this specie. The dosis and schedule of application were based on the guides ASTM, FETAX, OECD, as well as on the results published by: Herkovits.J and Pérez-Coll, C.S.,Rend.G.M.,Bantle.J.A and Agostinho.C.A. Designs were tested based on the use of single and repeated dosis of HCG and the combination of FSH plus HCG. The expected results were seen when a dose of 0.007 mg FSH/gpv was administered to both sexes and 24 hours after two dosis of HCG. Next day, around 1000-1400 eggs were produced, with a fertilization per cent higher than 75, a 0% of malformation and more than 80% of survival to the embryonary stage E-13 (Gosner 1960). It was concluded that O. Septentrionalis can be reproduced under laboratory conditions and the most appropiate protocol for the ovulation and fecundation of eggs was the combination of FSH and HCG.
The Feeding Strategy of Rana pleuraden from Kunming, China
昆明滇蛙的取食策略

ZHOU Wei,PAN Xiao-fu,OU Xiao-hong,LI Wei,
周 伟

动物学研究 , 2007,
Abstract: Until now, the correlation between the food found in a frog's stomach and the richness of food resources in their habitats were not fully considered when food selection of amphibians was studied in China. The diet of 494 specimens of Rana pleuraden were collected from Bailongsi and Xijiekou, Kunming, and the composition of the food resource in their habitats were investigated. The results showed that the food consumption of the frog and the food resource composition in the habitats were steady. The main groups of food resources were Orthoptera, Homoptera, Hemiptera, Coleoptera, Diptera, Lepidoptera, Hymenoptera and Arachnida. However, the proportion of each group varied among specimens from different localities, years and months of the year. Rana pleuraden also showed selectivity towards its food and/or prey, supported by the results of scientific analyses, such as the discrepancy significance analysis, the correlation analysis and the selectivity analysis between food consumption and food resources. There was no correlation between food resource found in the habitats and the food in the frog's stomach (Bailongsi: r=0.077, P=0.575; Xiejiekou: r=-0.086, P=0.500). The insects of Orthoptera (Ei<-0.35) and Homoptera (Ei<-0.37) were avoided when feeding. The insects of Coleoptera, Lepidoptera, Hymenoptera and Arachnida were the preferred prey for Rana pleuraden (Ei>0.45).
Using RAPD Method on Systematic Evolution of Four Species in Anura
用RAPD分析四种无尾类的系统演化关系

林玮,郑翠芳
动物学研究 , 2001,
Abstract: The phylogenetic relationships of four species,Bufo melanostictus,Hyla chinensis,Rana limnocharis and Rana guentheri,which belong to three differrent families of Anura,were detected with RAPD technique.The genomic DNA of each species was amplified with 19 random primers.16 primers given clear amplified bands were used for analysis and the genetic distances between four species were calculated.The results show that RAPD bands obtained by all 16 primers evinced different degree polymorphisms.The genetic distance between R.limnocharis and R.guentheri is the nearest,that between B.melanostictus and H.chinensis is the second nearest,and that between B.melanostictus and R.guentheri is the furthest.The different distances also indicated that the relationship between Bufoidae and Hylidae is closer than that between Bufonidae and Ranidae at genomic DNA level.In concordant with the conclusion of the morphology,chromosomal and mitochondrial DNA studies,our results provide a new evidence of the systematic evolution of the three families of Anura at DNA molecular level.
Comparison of Food Components Between Rana pleuraden and Rana chaochiaoensis from Kunming and Evaluation of Their Benefit and Harm
昆明滇蛙和昭觉林蛙食物比较及益害评价

ZHOU Wei,PAN Xiao-fu,OU Xiao-hong,ZHANG Qing,
周伟

动物学研究 , 2007,
Abstract: Food components of 1 105 individuals of Ranapleuraden and 428 Rana chaochiaoensis collected from Bailongsi, Huahongdong and Xijiekou of Kunming from May 1998 to November 2003 were analyzed by dissecting their stomachs. It was calculated that percentage of number and frequency, a diversity index, index of percent similarity, width of trophic ecological niche, overlap of trophic ecological niche and beneficial coefficient of the two frog species. According to results, major food components of different populations of R. pleuraden collected from different localities as well between R. pleuraden and R. chaochiaoensis were basically identical. However, there were differentiation in food diversity and trophic ecological niche between R. pleuraden and R. chaochiaoensis as well between their males and females. The annual beneficial coefficients of both R. pleuraden and R. chaochiaoensis were positive, which implied that their benefit for mankind was larger than harm. The beneficial level of R. pleuraden was higher than one of R. chaochiaoensis. The study results showed that beneficial coefficient could be changed among populations of a species collected from different regions and/or the same population collected from different seasons or years, which meant that the beneficial coefficient could not be compared. This coefficient only expressed the level of benefit and harm for mankind in the certain period.
Helminth fauna of Lithobates brownorum (Anura: Ranidae) at three localities in the state of Yucatán, Mexico Helmintofauna de Lithobates brownorum (Anura: Ranidae) en tres localidades del estado de Yucatán, México  [cached]
Carlos A. Yá?ez-Arenas,Sergio Guillén-Hernández
Revista mexicana de biodiversidad , 2010,
Abstract: Between July 2004 and June 2005, 84 specimens of Lithobates brownorum (Sanders, 1973) were collected and examined for helminths. Hosts came from 3 localities in the state of Yucatán, Mexico: Celestún (n= 35), Lagunas de Yalahau (n= 33), and Ría Lagartos (n= 16). Twelve helminth taxa were found: 7 nematodes, 4 digeneans, and 1 acanthocephalan. With the exception of Haematoloechus floedae and Megalodiscus temperatus, all helminth taxa found have a Neotropical distribution. Our results differ from those obtained in previous studies dealing with amphibians in Mexico because we found higher richness and abundance of nematodes than digenean species. The relatively low mean intensity and mean abundance values reached by digenean species in this study may be related to the generalist host diet and with the vagility of frogs (from the aquatic to the terrestrial environment or vice versa). Entre julio del 2004 y junio del 2005, se recolectaron y examinaron 84 ejemplares de Lithobates brownorum (Sanders, 1973) en busca de helmintos en 3 localidades del estado de Yucatán: Celestún (n= 35), Lagunas de Yalahau (n= 33) y Ría Lagartos (n= 16). Los ejemplares estuvieron parasitados por 12 taxa de helmintos, 7 de nematodos, 4 digéneos y 1 acantocefalo. Con excepción de Haematoloechus floedae y Megalodiscus temperatus, todos los taxa presentan distribución neotropical. Nuestros resultados difieren de los obtenidos por otros autores que han reportado más especies de digéneos que de nematodos en este grupo de hospederos. Los bajos valores de intensidad y abundancia media de los digéneos encontrados en este estudio pueden estar relacionados con la amplia dieta del hospedero y la vagilidad que éste presenta entre el medio acuático y el terrestre.
Postglacial Colonization of the Qinling Mountains: Phylogeography of the Swelled Vent Frog (Feirana quadranus)  [PDF]
Bin Wang, Jianping Jiang, Feng Xie, Cheng Li
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0041579
Abstract: Background The influence of Pleistocene climatic fluctuations on intraspecific diversification in the Qinling–Daba Mountains of East Asia remains poorly investigated. We tested hypotheses concerning refugia during the last glacial maximum (LGM) in this region by examining the phylogeography of the swelled vent frog (Feirana quadranus; Dicroglossidae, Anura, Amphibia). Methodology/Principal Findings We obtained complete mitochondrial ND2 gene sequences of 224 individuals from 34 populations of Feirana quadranus for phylogeographic analyses. Additionally, we obtained nuclear tyrosinase gene sequences of 68 F. quadranus, one F. kangxianensis and three F. taihangnica samples to test for mitochondrial introgression among them. Phylogenetic analyses based on all genes revealed no introgression among them. Phylogenetic analyses based on ND2 datasets revealed that F. quadranus was comprised of six lineages which were separated by deep valleys; the sole exception is that the Main Qinling and Micang–Western Qinling lineages overlap in distribution. Analyses of population structure indicated restricted gene flow among lineages. Coalescent simulations and divergence dating indicated that the basal diversification within F. quadranus may be associated with the dramatic uplifts of the Tibetan Plateau during the Pliocene. Coalescent simulations indicated that Wuling, Daba, and Western Qinling–Micang–Longmen Mountains were refugia for F. quadranus during the LGM. Demographic analyses indicated that the Daba lineage experienced population size increase prior to the LGM but the Main Qinling and the Micang–Western Qinling lineages expanded in population size and range after the LGM, and the other lineages almost have stable population size or slight slow population size decline. Conclusions/Significance The Qinling–Daba Mountains hosted three refugia for F. quadranus during the LGM. Populations that originated in the Daba Mountains colonized the Main Qinling Mountains after the LGM. Recent sharp expansion of the Micang–Western Qinling and Main Qinling lineages probably contribute to their present-day secondary contact.
New Routes to Phylogeography  [PDF]
Nicola De Maio,Chieh-Hsi Wu,Kathleen M O'Reilly,Daniel Wilson
Quantitative Biology , 2015,
Abstract: Phylogeographic methods aim to infer migration trends and the history of sampled lineages from genetic data. Applications of phylogeography are broad, and in the context of pathogens include the reconstruction of transmission histories and the origin and emergence of outbreaks. Phylogeographic inference based on bottom-up population genetics models is computationally expensive, and as a result faster alternatives based on the evolution of discrete traits have become popular. In this paper, we show that inference of migration rates and root locations based on discrete trait models is extremely unreliable and sensitive to biased sampling. To address this problem, we introduce BASTA (BAyesian STructured coalescent Approximation), a new approach implemented in BEAST2 that combines the accuracy of methods based on the structured coalescent with the computational efficiency required to handle more than just few populations. We illustrate the potentially severe implications of poor model choice for phylogeographic analyses by investigating the zoonotic transmission of Ebola virus. Whereas the structured coalescent analysis correctly infers that successive human Ebola outbreaks have been seeded by a large unsampled non-human reservoir population, the discrete trait analysis implausibly concludes that undetected human-to-human transmission has allowed the virus to persist over the past four decades. As genomics takes on an increasingly prominent role informing the control and prevention of infectious diseases, it will be vital that phylogeographic inference provides robust insights into transmission history.
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