Various types of gene rearrangements have been discovered in the mitogenoes of the frog family Ranidae. In this study, we determined the complete mitogenome sequence of three Rana frogs. By combining the available mit...Various types of gene rearrangements have been discovered in the mitogenoes of the frog family Ranidae. In this study, we determined the complete mitogenome sequence of three Rana frogs. By combining the available mitogenomic data sets from GenBank, we evaluated the phylogenetic relationships of Ranidae at the mitogenome level and analyzed mitogenome rearrangement cases within Ranidae. The three frogs shared an identical mitogenome organization that was extremely similar to the typical Neobatrachian-type arrangement. Except for the genus Babina, the monophyly of each genus was well supported. The genus Amnirana occupied the most basal position among the Ranidae. The [Lithobates ＋ Rana] was the closest sister group of Odorrana. The diversity of mitochondrial gene arrangements in ranid species was unexpectedly high, with 47 mitogenomes from 40 ranids being classified into 10 different gene rearrangement types. Some taxa owned their unique gene rearrangement characteristics, which had significant implication for their phylogeny analysis. All rearrangement events discovered in the Ranidae mitogenomes can be explained by the duplication and random loss model.展开更多
The chromosomes of three odor frogs, Luetuosae- group of Rana were analyzed by conventional, as well as Obanding and silver staining techniques. The three species here examined all had 26 chromosome karyotypes encompa...The chromosomes of three odor frogs, Luetuosae- group of Rana were analyzed by conventional, as well as Obanding and silver staining techniques. The three species here examined all had 26 chromosome karyotypes encompassing 5 large and 8 small homologous pairs. Differences among them were found in gross shapes of chromosomes and positions of secondary constrictions. Generally speaking, karyotypes of R. andersonii and R. grahami resembled each other, while the karyotype of R. tiannanensis differed from the former two in several respects.Analyses of karyotypes by C-banding technique indicated that, centromeric areas of every chromosome and interstitial parts of some chromosomes of each species were hetero-chromatinized, and differences of distribution of heterochromatin were found among species. In early metaphase plates of R. andersonii, much more heterochromatinized areas were observed, and when it reached late metaphase, the numbers of heterochromatin sections in each chromosome pair reduced to a limited level, e. g. centromeres and a few interstitial parts.The active nucleolar organizer regions (NORs) were localized in long arms of pair No. 10, in connection with secondary constrictions for R. andersonii and R. grahami as in other odor frogs previously reported, but in the long arm of pair No. 6 for R. tiannanensis.The cytogenetic and taxonomic implications of the findings were discussed based on comparisons with each other, and with published literature.展开更多
The population density and breeding of two frog species, i. e., the Skittering Frog （Euphlyctis eyanophlyctis） and the Bull Frog （Hoplobatrachus tigerinus） were studied at Rawal Lake, Islamabad, Pakistan, by using...The population density and breeding of two frog species, i. e., the Skittering Frog （Euphlyctis eyanophlyctis） and the Bull Frog （Hoplobatrachus tigerinus） were studied at Rawal Lake, Islamabad, Pakistan, by using visual encounter method from September 2009 to August 2010. Mean population density for the two frogs was 1.55 ± 0.44 frogs per ha, with that for the Skittering Frog being 1.09 ± 0.33 frogs/ha and that of the Bull Frog 0.46 ± 0.11 frog/ha, respectively. It is concluded that both frog species are explosive breeders, i. e., their breeding activities were confined to the first showers of the monsoon season. The mean spawn weight of the Skittering Frog was 1.5 g with more than 1000 eggs in each spawn, while that of the Bull Frog was 0.26 g with less than 1000 eggs in a spawn. The spawning sites of the two species were investigated in detail. Generally, no threat to their populations was observed. However, the opening of the spillway of Rawal Dam following the torrential rain destroyed the breeding sites of the frogs. It is maintained that the event did not produce any significant impact on their populations and breeding as the two species were quite common.展开更多
基金supported by the Innovative Research Team in University of Sichuan Bureau of Education (No.14TD0002)the Scientific Research Fund of Sichuan Provincial Education Department (No.11ZA077)
文摘Various types of gene rearrangements have been discovered in the mitogenoes of the frog family Ranidae. In this study, we determined the complete mitogenome sequence of three Rana frogs. By combining the available mitogenomic data sets from GenBank, we evaluated the phylogenetic relationships of Ranidae at the mitogenome level and analyzed mitogenome rearrangement cases within Ranidae. The three frogs shared an identical mitogenome organization that was extremely similar to the typical Neobatrachian-type arrangement. Except for the genus Babina, the monophyly of each genus was well supported. The genus Amnirana occupied the most basal position among the Ranidae. The [Lithobates ＋ Rana] was the closest sister group of Odorrana. The diversity of mitochondrial gene arrangements in ranid species was unexpectedly high, with 47 mitogenomes from 40 ranids being classified into 10 different gene rearrangement types. Some taxa owned their unique gene rearrangement characteristics, which had significant implication for their phylogeny analysis. All rearrangement events discovered in the Ranidae mitogenomes can be explained by the duplication and random loss model.
文摘The chromosomes of three odor frogs, Luetuosae- group of Rana were analyzed by conventional, as well as Obanding and silver staining techniques. The three species here examined all had 26 chromosome karyotypes encompassing 5 large and 8 small homologous pairs. Differences among them were found in gross shapes of chromosomes and positions of secondary constrictions. Generally speaking, karyotypes of R. andersonii and R. grahami resembled each other, while the karyotype of R. tiannanensis differed from the former two in several respects.Analyses of karyotypes by C-banding technique indicated that, centromeric areas of every chromosome and interstitial parts of some chromosomes of each species were hetero-chromatinized, and differences of distribution of heterochromatin were found among species. In early metaphase plates of R. andersonii, much more heterochromatinized areas were observed, and when it reached late metaphase, the numbers of heterochromatin sections in each chromosome pair reduced to a limited level, e. g. centromeres and a few interstitial parts.The active nucleolar organizer regions (NORs) were localized in long arms of pair No. 10, in connection with secondary constrictions for R. andersonii and R. grahami as in other odor frogs previously reported, but in the long arm of pair No. 6 for R. tiannanensis.The cytogenetic and taxonomic implications of the findings were discussed based on comparisons with each other, and with published literature.
文摘The population density and breeding of two frog species, i. e., the Skittering Frog （Euphlyctis eyanophlyctis） and the Bull Frog （Hoplobatrachus tigerinus） were studied at Rawal Lake, Islamabad, Pakistan, by using visual encounter method from September 2009 to August 2010. Mean population density for the two frogs was 1.55 ± 0.44 frogs per ha, with that for the Skittering Frog being 1.09 ± 0.33 frogs/ha and that of the Bull Frog 0.46 ± 0.11 frog/ha, respectively. It is concluded that both frog species are explosive breeders, i. e., their breeding activities were confined to the first showers of the monsoon season. The mean spawn weight of the Skittering Frog was 1.5 g with more than 1000 eggs in each spawn, while that of the Bull Frog was 0.26 g with less than 1000 eggs in a spawn. The spawning sites of the two species were investigated in detail. Generally, no threat to their populations was observed. However, the opening of the spillway of Rawal Dam following the torrential rain destroyed the breeding sites of the frogs. It is maintained that the event did not produce any significant impact on their populations and breeding as the two species were quite common.
