摘要 :
Understanding community ecology mechanisms requires that scientists, among other investigation tasks, should explore whether a given pattern deviates from patterns expected under specified conditions (e.g. Barbault, 1981; Blondel,...
展开
Understanding community ecology mechanisms requires that scientists, among other investigation tasks, should explore whether a given pattern deviates from patterns expected under specified conditions (e.g. Barbault, 1981; Blondel, 1986; Gotelli & Graves, 1996; Hoagland & Collins, 1997; Sanderson, 2004). To investigate expected versus deviant from expected patterns, it is important to study communities inhabiting networks of patchily distributed suitable habitats with contrasted structural features (e.g. climax versus pioneer condition in time-series vegetation data, pristine versus altered habitats, continuous versus fragmented habitats, etc.). Wetlands are typically habitats with patchy and discontinuous distribution, and may be considered like islands of suitable habitat interspersed within a sea of sub-suitable matrix. In a hypothetical pond network, the co-occurrence patterns of the sheltered species may mirror how the different conditions of each pond (e.g. natural versus artificial water basins) affect assembly rules and interspecific relationships.
收起
摘要 :
Acris gryllus paludicola, the Coastal Cricket Frog, was described from Sabine Pass, Jefferson County, Texas, by L. W. Burger, P. W. Smith, and H. M. Smith in 1949. Additional specimens have not been reported or examined in the lit...
展开
Acris gryllus paludicola, the Coastal Cricket Frog, was described from Sabine Pass, Jefferson County, Texas, by L. W. Burger, P. W. Smith, and H. M. Smith in 1949. Additional specimens have not been reported or examined in the literature. At the time of its description, the association with Acris gryllus was parsimonious with the then-current understanding of the taxonomic position of the two species within the genus, A. gryllus and Acris crepitans. All subspecies within the genus were described within four years of each other, and all were subspecies of A. gryllus. The Coastal Cricket Frog is currently treated as a subspecies of A. crepitmis but without an explicit treatment resolving its species level affinity. Seven individuals found on 19 May 2005 near the type locality are relatively smooth skinned; have reduced, or lack, anal warts; and retain ill-defined postfemoral striping; vocalizing males. have pink-rose colored vocal pouches. Phenotypic comparison of the seven specimens fails to eliminate their inclusion in the species A. gryllus. Concurrent mtDNA sequence comparisons with A. gryllus from Florida and a series of A. crepitans from Texas confirm that the Coastal Cricket Frog is nested within the A. crepitans clade distinct from A. gryllus. We conclude that the original description of the "pink" frog is supported by examination of living specimens and have no evidence indicating that its subspecific status within A. crepitans should be questioned. Recent work within this genus has highlighted the need for an exhaustive study of the variation it presents rangewide.
收起
摘要 :
A new species, Alsodes igneus, from the temperate Nothofagus forest, western slopes of the Andes Range, southern Chile, is described. This species is characterized by the combination of the following characters: snout short slight...
展开
A new species, Alsodes igneus, from the temperate Nothofagus forest, western slopes of the Andes Range, southern Chile, is described. This species is characterized by the combination of the following characters: snout short slightly truncated in dorsal view, a black ribbon extending below the canthus rostralis, unbarred legs and arms, heel not reaching the posterior border of the eye when hind leg is bent forward, toes scarcely fringed, webbing absent, dorsal surface granular. Its karyotype has 26 bi-armed chromosomes and it is characterized by presenting the secondary constriction and nucleolus organizer regions in the short arm of pair seven.
收起
摘要 :
The selection of suitable oviposition sites is crucial for successful reproduction of many organisms, including the endangered Madagascan frog Aglyptodactylus laticeps. In a preceding study, a conservation-oriented model of habita...
展开
The selection of suitable oviposition sites is crucial for successful reproduction of many organisms, including the endangered Madagascan frog Aglyptodactylus laticeps. In a preceding study, a conservation-oriented model of habitat use for this species extracted key habitat factors that reliably predict whether given ponds are used as oviposition sites. However, habitat-use models are descriptive and thus their explanatory power for true causal relationships between habitat variables and species distributions is presumably limited. Furthermore, these models are mostly insufficient with regard to incorporating dynamic components of habitat choice, such as the colonization history. Therefore, the explanatory power of habitat-use models within the context of dynamic components was experimentally investigated by creating artificial breeding ponds in the natural habitat of this frog species and manipulating two environmental factors within these breeding ponds. The absence of tadpoles proved to be the most decisive factor determining colonization. Leaf litter on the pond bottom, that had been suggested to be of importance by the habitat-use model, did not influence oviposition-site selection. Although pond characteristics may be important, the overriding factor affecting pond use in the experimental study was avoidance of pools that already contained tadpoles by ovipositing adults.
收起
摘要 :
A new species of Plectrohyla is described from the Sierra de Miahuatlan in southern Oaxaca, Mexico. It is known from a single adult female obtained from pine-oak forest at 2550 m. The new species is similar to Plectrohyla cembra i...
展开
A new species of Plectrohyla is described from the Sierra de Miahuatlan in southern Oaxaca, Mexico. It is known from a single adult female obtained from pine-oak forest at 2550 m. The new species is similar to Plectrohyla cembra in size, habitus, and in having a partially concealed tympanum but differs most notably in aspects of color pattern, hand morphology, head shape, and palatine features.
收起
摘要 :
Rhacophorus georgii is a poorly known species from southeast Asia. The morphology and habitat of oviposition and the tadpole of Rhacophorus georgii are described, and counts of ovarian egg compliments reported. Tadpoles were locat...
展开
Rhacophorus georgii is a poorly known species from southeast Asia. The morphology and habitat of oviposition and the tadpole of Rhacophorus georgii are described, and counts of ovarian egg compliments reported. Tadpoles were located in water pools in cavities of tree trunks in the Lambusango Reserve, Buton Island, southeast Sulawesi. The tadpole generally conforms to a lentic, benthic morphotype, with an anteroventral mouth, somewhat depressed body and notably elongated tail. Foamy egg masses were located attached to the trunks of trees, 1-3 cm above water-filled tree cavities. Ovarian egg complements recorded were 29-108. These findings make a significant contribution to the knowledge of the frog fauna of Sulawesi.
收起
摘要 :
Hyla camposseabrai Bokermann, 1968, was described based on specimens obtained at MaracAs, State of Bahia, Brazil. It was subsequently considered as a subspecies of Hyla x-signata Spix, 1824, and currently it has been considered a ...
展开
Hyla camposseabrai Bokermann, 1968, was described based on specimens obtained at MaracAs, State of Bahia, Brazil. It was subsequently considered as a subspecies of Hyla x-signata Spix, 1824, and currently it has been considered a synonym of Scinax x-signatus (Spix, 1824). In this paper, the status of the species is revalidated and the new combination Scinax camposseabrai is established.
收起
摘要 :
A new arboreal species of Rhinella is described from the humid montane forest of Mann National Park in the Cordillera Oriental of southern Peru. The new species can be distinguished from all known Rhinella by a unique combination ...
展开
A new arboreal species of Rhinella is described from the humid montane forest of Mann National Park in the Cordillera Oriental of southern Peru. The new species can be distinguished from all known Rhinella by a unique combination of external and osteological characters as well as by molecular data. The new toad is compared to R. arborescandens and R. veraguensis with respect to external characters. On the basis of morphological and molecular data, the new taxon is closely related to R. chavin, R. nesiotes, and R. festae. Although DNA data indicate that a member of the R. veraguensis group (R. nesiotes) is its sister taxon, the new species is not closely related to other members of this species group (e.g., R. veraguensis). In addition, DNA data indicate that the R. veraguensis group as it currently is defined is paraphyletic. Until additional studies are completed on the phylogeny of these South American toads, we refrain from assigning the new taxon to a species group.
收起
摘要 :
We describe a new species of Cochranella from cloud forests in La Paz, Bolivia. The new species is assigned to the C. granulosa Group and characterized by the presence of crenulate folds, distinctive coloration, and the first fing...
展开
We describe a new species of Cochranella from cloud forests in La Paz, Bolivia. The new species is assigned to the C. granulosa Group and characterized by the presence of crenulate folds, distinctive coloration, and the first finger shorter than the second. The new species occurs in sympatry with C. spiculata and C. sp.
收起
摘要 :
Population declines and range contractions among Australian frogs that commenced in the early 1980s continue in some species that were once widespread. The generality of this pattern has been difficult to discern, especially for t...
展开
Population declines and range contractions among Australian frogs that commenced in the early 1980s continue in some species that were once widespread. The generality of this pattern has been difficult to discern, especially for those species that are encountered rarely because they have restricted periods of calling activity with poorly defined habitat preferences, and are not common. Several lines of evidence indicate that Litoria littlejohni is such a species. This frog was once known from mid-eastern New South Wales to eastern Victoria, and evidence from wildlife atlas databases and targeted searches indicate that it has declined in large portions of its former range, leaving several populations that are isolated, in some cases restricted in distribution, and of small size. We investigated the relationships among populations using mitochondrial ND4 nucleotide sequences and single nucleotide polymorphisms (SNPs) from the nuclear genome. We found that northern and southern populations form two highly divergent genetic groups whose distributions abut at the southern margin of the Sydney Basin Bioregion and these genetic groups also show divergence in morphology and male advertisement calls. Here we describe the populations to the south of the Sydney Basin Bioregion as a new species and provide information on its distribution and ecology. In light of the apparent isolation and small size of known populations of the new species and the consequent restriction of the range of L. littlejohni, we assessed the conservation status of both species.
收起
原文获取