Phylogenetic relationships of the North American chorus frogs (Pseudacris: Hylidae)

We examined phylogenetic relationships of the North American chorus frogs (Pseudacris: Hylidae) from 38 populations using 2.4 kb of 12S and 16S mtDNA to elucidate species relationships and examine congruence of previous phylogenetic hypotheses. Parsimony, maximum likelihood, and Bayesian phylogenies are consistent and reveal four strongly supported clades within Pseudacris: (1). A West Coast Clade containing regilla and cadaverina, (2). a Fat Frog Clade including ornata, streckeri, and illinoensis, (3). a Crucifer Clade consisting of crucifer and ocularis, and (4). a Trilling Frog Clade containing all other Pseudacris. Explicit hypothesis testing using parametric bootstrapping indicates that previous phylogenetic hypotheses are rejected by our sequence dataset. Within the Trilling Frog Clade, brimleyi and brachyphona form the sister group to the Nigrita Clade: nigrita, feriarum, triseriata, kalmi, clarkii, and maculata. The Nigrita Clade shows geographic division into three clades: (1). populations of maculata and triseriata west of the Mississippi River and Canadian populations, (2). southeastern US populations of feriarum and nigrita, and (3). northeastern US populations of feriarum, kalmi, and triseriata. We find that subspecific epithets for crucifer (crucifer and bartramiana) and nigrita (nigrita and verrucosa) are uninformative, therefore we discourage recognition of these subspecies. Pseudacris regilla, cadaverina, ocularis, and crucifer are maintained in Pseudacris.     

Cryptic lineages in a small frog: the post-glacial history of the spring peeper,Pseudacris crucifer (Anura: Hylidae)

The spring peeper (Pseudacris crucifer) is believed to have been a primary herpetological invader of eastern North America following the most recent period of glacial retreat. We examined the phylogeographic pattern and population structure of P. crucifer to determine whether the distribution of haplotypic variants reflect post-Pleistocene recolonization dynamics. A number of geographically isolated evolutionary lineages were supported by both maximum parsimony and neighbor-joining analyses, and by coalescence approaches applied to mtDNA. South-western Ontario represents a high level of genotypic diversity (pi) due to the presence of two divergent lineages. The geographic distribution of these lineages are interpreted as reflecting post-glacial recolonization dynamics from separate, isolated refugia during the late Pleistocene that have come into secondary contact in SW Ontario. The phylogenetic placement of haplotypes from the range of P. crucifer bartramiana (Florida and South Carolina) does not allow for monophyly of P. crucifer crucifer, and therefore the bartramiana subspecies designation does not reflect a separate evolutionary lineage.     

Serous cutaneous glands of the Pacific tree-frog Hyla regilla (Anura, Hylidae): patterns of secretory release induced by nor-epinephrine

The serous (poison) cutaneous glands of the Pacific tree-frog Hyla regilla were induced to release their product by 10(-3)M nor-epinephrine stimulation. After discharge structural and ultrastructural features of the cutaneous glands involved in release were observed. Furthermore, the discharged product, consisting of discrete, secretory granules, was collected and processed for transmission electron microscope analysis. As indicated by patterns found in the myoepithelium encircling the syncytial secretory unit, gland discharge is caused by contraction of the peripheral myocytes. Muscle cell compression dramatically affects the syncytium and results in degenerative changes, including expulsion of the secretory unit nuclei. Therefore, the structural collapse in depleted glands has been ascribed to the mechanical activity performed by the myoepithelium during discharge, rather than cytoplasm involution described in conventional, holocrine glands. TEM investigation revealed that the secretory granules collected after discharge maintain their peculiar traits: they consist of recurrent patterns of thin subunits, acquired during serous maturation and provided with remarkable structural stability.     

A new species of Osteocephalus (Anura: Hylidae) from Guyana.

A new member of the genus Osteocephalus is described from the Pakaraima mountains of western Guyana. This species is the smallest known member of the genus and is probably closely related to O. subtilis. Both share a small size (less than 40 mm snout-vent length), large and bulgy eyes directed somewhat rostrally, green bones, smooth and brownish dorsal skin, relatively short and truncate snout, small tympanum, subgular and laterally expanded vocal sac, poorly developed subarticular and supernumerary tubercles, a supra-anal glandular ridge, and cream-white venter and subocular region. The new species can be distinguished from O. subtilis by the Buff iris (vs black), smaller overall size (32.7 vs 35.8-38.8 mm snout-vent length), relatively larger toe disks, and less developed foot webbing. The cranium of the new species is well ossified, relatively reduced in width between the orbits, without an exposed frontoparietal fontanelle and with the anterior arm of the squamosal extending to about half the distance to the maxillary. The vocal sac is subgularly poorly developed and possess lateral extensions to the area behind the jaw angles. Well developed supraocular and suprasquamosal cartilages give support to the enlarged eyes of this species.     

Sound Pattern Recognition in Some North American Treefrogs (Anura: Hylidae): Implications for Mate Choice

SYNOPSIS. Playback experiments using synthetic sounds indicatethat gravid females of the gray treefrogs (Hyla versicolor andH. chrysoscelis) and the green treefrog (H. cinerea) selectivelyrespond to sounds on the basis of physical properties that showinter-individual variation in the calls of conspecific males.Although the specificity is adequate to differentiate amongthe signals of many males, this potential for mate choice maynot be fully realized in acoustically complex situations suchas natural breeding aggregations. Female selectivity in H. cinereawas less precise in four-speaker experiments than in two-speakerexperiments. An analysis of female preferences with respectto a call property correlated with body size was only partiallysuccessful in predicting the size distribution of successfulmales in a natural population. Finally, the existence of othersynchronously breeding species of frogs with similar calls mayimpose significant constraints on intraspecific mate choice,and female specificity with respect to some acoustic propertiesof mating calls is difficult to explain otherwise.     

A cladistic analysis of Scinax (Anura: Hylidae)

The hylid frog genus Scinax ranges from southern Mexico to eastern Argentina. The 84 recognized species are currently arranged in five groups: the Scinax rubra , Scinax rostrata , Scinax catharinae , Scinax staufferi , and Scinax perpusilla species groups. Although a few species groups are distinctive, compelling evidence of monophyly is lacking for three groups, and their interrelationships remain virtually unknown. With the objective of testing the monophyly of the species groups and exploring their interrelationships, a cladistic analysis was performed, employing 86 characters from osteology, myology, adult and larval external morphology, reproductive biology, and karyotypes taken from 36 representative species of the five species groups plus eight outgroup taxa. The analysis of the resulting data matrix shows moderately well-supported (as assessed through Bremer support and parsimony jackknifing) S. catharinae and S. rostrata species groups. The S. staufferi species group is polyphyletic, as currently composed, given that some of its species are nested within the S. catharinae species group. The only representative of the S. perpusilla species group is the sister species of the S. catharinae species group. Although weakly supported, the representatives of the S. rostrata and S. staufferi species groups are nested, separately, within the S. rubra species group. In order to have a taxonomy consistent with these results, it is proposed not to recognize the S. rubra group but to recognize a more inclusive rubra clade that includes all studied exemplars of the former S. rubra group, plus some of the S. staufferi group and all of the S. rostrata group. Similarly, a catharinae clade is recognized, within which all studied exemplars of the S. catharina e group (that now includes Scinax berthae and Scinax agilis ) and the one studied representative of the S. perpusilla group are included.     

The phylogeny of Dendropsophini (Anura: Hylidae: Hylinae)

The relationships of the hyline tribe Dendropsophini remain poorly studied, with most published analyses dealing with few of the species groups of Dendropsophus. In order to test the monophyly of Dendropsophini, its genera, and the species groups currently recognized in Dendropsophus, we performed a total evidence phylogenetic analysis. The molecular dataset included sequences of three mitochondrial and five nuclear genes from 210 terminals, including 12 outgroup species, the two species of Xenohyla, and 93 of the 108 recognized species of Dendropsophus. The phenomic dataset includes 46 terminals, one per species (34 Dendropsophus, one Xenohyla, and 11 outgroup species). Our results corroborate the monophyly of Dendropsophini and the reciprocal monophyly of Dendropsophus and Xenohyla. Some species groups of Dendropsophus are paraphyletic (the D. microcephalus, D. minimus, and D. parviceps groups, and the D. rubicundulus clade). On the basis of our results, we recognize nine species groups; for three of them (D. leucophyllatus, D. microcephalus, and D. parviceps groups) we recognize some nominal clades to highlight specific morphology or relationships and facilitate species taxonomy. We further discuss the evolution of oviposition site selection, where our results show multiple instances of independent evolution of terrestrial egg clutches during the evolutionary history of Dendropsophus.     

Phylogeography of Iberian Discoglossus (Anura: Discoglossidae)

The genus Discoglossus (Anura, Discoglossidae) comprises five morphologically similar species. Molecular analyses have found high values of genetic differentiation among these cryptic taxa and confirmed the existence of two Iberian endemic lineages ( Discoglossus galganoi and D. jeanneae ) and a distinct lineage of uncertain origin representing a third species in NE Spain. In order to analyse the pattern of geographical distribution of haplotype diversity within Iberian Discoglossus and test the hypothesis of an Algerian origin for populations in NE Spain sequence data has been resolved from 35 populations of D. galganoi and D. jeanneae on the Iberian Peninsula and samples from NE Spain and north Africa. I analysed 959 bp corresponding to partial sequences of cytochrome b and nad 4 and found extremely low values of sequence divergence among populations of D. jeanneae . Three clades can be recognized within D. galganoi , however, and a statistically significant association with geography can be explained as a result of past fragmentation. Sequence data strongly support an Algerian origin for populations of Discoglossus from NE Spain. Finally, the taxonomic status of Discoglossus in Morocco is discussed and its elevation to species status as Discoglossus scovazzi Camerano, 1878 is suggested.     

Phylogeography of a widespread small carnivore,the western spotted skunk (Spilogale gracilis) reveals temporally variable signatures of isolation across western North America

We analyzed phylogeographic patterns in the western spotted skunk, Spilogale gracilis Merriam, 1890 (Carnivora: Mephitidae) in relation to historical events associated with Pre‐Pleistocene Divergence (PPD) and Quaternary climate change (QCC) using mitochondrial DNA from 97 individuals distributed across Western North America. Divergence times were generated using BEAST to estimate when isolation in putative refugia occurred. Patterns and timing of demographic expansion was performed using Bayesian skyline plot. Putative climatic refugia resulting from Quaternary climate change were identified using paleoecological niche modeling and divergence dates compared to major vicariant events associated with Pre‐Pleistocene conditions. We recovered three major mitochondrial clades corresponding to western North America (California, Baja, and across the Great Basin), east‐central North America (Texas, central Mexico, New Mexico), and southwestern Arizona/northwestern Mexico. Time to most recent common ancestor for S. gracilis occurred ~1.36 Ma. Divergence times for each major clade occurred between 0.25 and 0.12 Ma, with signature of population expansion occurring 0.15 and 0.10 Ma. Ecological niche models identified three potential climatic refugia during the Last Interglacial, (1) west coast of California and Oregon, (2) northwestern Mexico, and (3) southern Texas/northeastern Mexico as well as two refugia during the Last Glacial Maximum, (1) western USA and (2) southern Texas/northeastern Mexico. This study supports PPD in shaping species‐level diversity compared to QCC‐driven changes at the intraspecific level for Spilogale, similar to the patterns reported for other small mammals (e.g., rodents and bats). Phylogeographic patterns also appear to have been shaped by both habitat and river vicariance, especially across the desert southwest. Further, continuing climate change during the Holocene coupled with anthropogenic modifications during the Anthropocene appears to be removing both of these barriers to current dispersal of western spotted skunks.     

Phylogeography of Ramalina menziesii,a widely distributed lichen‐forming fungus in western North America

The complex topography and climate history of western North America offer a setting where lineage formation, accumulation and migration have led to elevated inter‐ and intraspecific biodiversity in many taxa. Here, we study Ramalina menziesii, an epiphytic lichenized fungus with a range encompassing major ecosystems from Baja California to Alaska to explore the predictions of two hypotheses: (i) that the widespread distribution of R. menziesii is due to a single migration episode from a single lineage and (ii) that the widespread distribution is due to the formation and persistence of multiple lineages structured throughout the species' range. To obtain evidence for these predictions, we first construct a phylogenetic tree and identify multiple lineages structured throughout the species' range – some ancient ones that are localized and other more recent lineages that are widely distributed. Second, we use an isolation with migration model to show that sets of ecoregion populations diverged from each other at different times, demonstrating the importance of historical and current barriers to gene flow. Third, we estimated migration rates among ecoregions and find that Baja California populations are relatively isolated, that inland California ecoregion populations do not send out emigrants and that migration out of California coastal and Pacific Northwest populations into inland California ecoregions is high. Such intraspecific geographical patterns of population persistence and dispersal both contribute to the wide range of this genetically diverse lichen fungus and provide insight into the evolutionary processes that enhance species diversity of the California Floristic Province.     

Vocalizations of Hypsiboas goianus (Lutz, 1968) (Anura: Hylidae) in Central Brazil

Environmental and morphological factors and social context influence the vocalizations of anuran species. Herein, we observed the acoustic behavior of Hypsiboas goianus males from Central Brazil and analyzed the following calls: advertisement, short aggressive and long aggressive. The acoustic parameters of advertisement calls were not correlated with air temperature, mass or snout–vent length; however, the acoustic parameters of short aggressive calls were influenced by these variables. The temporal parameters of advertisement and short aggressive calls were classified as dynamic properties, while the dominant frequency was considered a static property. Dominant frequency is the most important variable to discriminate calls among individuals.     

A taxonomic revision of the Antennaria media (Asteraceae: Inuleae) polyploid species complex in western North America

TheAntennaria media polyploid species complex has been evaluated, at least in part, on numerous occasions without consensus on either the taxa that should be included within the complex or the rank at which these taxa should be recognized. The primary purpose of this quantitative, multivariate, phenetic study is to propose a taxonomy for the polyploid species complex that not only is independent of a knowledge of either chromosome number or reproductive biology but that concurrently minimally reflects morphological variation associated with each. The use of canonical discriminant analysis facilitates this purpose. In an attempt to maintain consistency with other recent revisions of polyploid complexes within the genus, the rank of subspecies (A. media subsp.media, A. media subsp.ciliata, A. media subsp.compacta, A. media subsp.fusca, andA. media subsp.pulchella) is selected as the infraspecific rank that satisfies the purpose of the phenetic study and is supported by the analyses. These subspecies differ to varying degrees with respect to reproductive characters (corolla length, pappus length), vegetative-reproductive characters (involucre length, peduncle length, cauline leaf length, cauline leaf width), and vegetative characters (basal leaf length and basal leaf width).Antennaria media subsp.pulchella is a sexually reproducing, diploid subspecies, whereas the remaining four subspecies are essentially agamospermous polyploids.     

Two new species of Cymopterus (Umbelliferae) from western North America

Two species ofCymopterus are described as new:Cymopterus douglassi from the Lost River and Lemhi ranges of central Idaho and the closely relatedC. williamsii from the southern half of the Big Horn Mountains, Wyoming. Both are diploid on the basex=11 and occur on calcareous or dolomitic substrates. The mature fruit ofCymopterus williamsii differ from those ofC. douglassii in the absence of a functioning carpophore and in having 1, not 3–5 oil tubes in the intervals. Both species are unusual in the genus, though not unique, in that the dorsal ribs of the mericarps are not winged.     

Phylogeography of Sylvirana latouchii (Anura, Ranidae) in Taiwan

Biogeographic studies are important for understanding the natural history of faunas. To comprehend the geographical patterns of genetic variation in anurans in Taiwan, we investigated the genetic structure of Sylvirana latouchii (Anura, Ranidae) from 31 populations by using mitochondrial DNA (mtDNA) cytochrome b sequences. A neighbor-joining tree of 38 haplotypes revealed three major divergences in Taiwanese S. latouchii: the northern, western, and eastern-and-southern clades. Each clade was restricted to a single geographical district and showed obvious differentiation. The patterns of geographical divergence in this species reflect common historical events experienced by other native animals distributed in Taiwan. The order of divergence times between clades was inferred using a molecular clock test. The population relationship of S. latouchii between Taiwan and mainland China is discussed. Further study employing more populations of S. latouchii from mainland China is necessary to clarify the original geographical patterns and migratory history of this species.     

Discordant temporal and geographic patterns in maternal lineages of eastern North American frogs, Rana catesbeiana (Ranidae) and Pseudacris crucifer (Hylidae)

Whether the Pleistocene has had a disproportionate impact on the recent diversification of temperate species, or played a lesser role in a more protracted process, has been a prominent evolutionary debate for the past decade. We used cytochrome b sequences to reconstruct the evolutionary histories of two widely co-distributed, and ecologically divergent frogs (Rana catesbeiana and Pseudacris crucifer) to examine the role of the Pleistocene in structuring these species. Results for R. catesbeiana reflect a pattern of allopatric fragmentation, likely in Coastal Plain refugia on either side of the Mississippi River dating to the mid to early Pleistocene. In contrast, P. crucifer contains numerous divergent lineages, including one west of the Mississippi River in the Interior Highlands, and in the east, multiple lineages that likely expanded from a number of southern Appalachian refugia with lineage sundering originating in the late Pliocene. Large-scale phylogeographic comparisons between these and other eastern North American species reflect both congruent and independent patterns of diversification, possibly reflecting the relative importance of dispersal ability and habitat associations. Although intra-lineage diversification has been structured by repeated Pleistocene glaciations, lineage sundering likely dates at least to the Pliocene in most (but not all) northern temperate amphibian and reptile species studied to date.     

Baeospora occidentalis, a new snowbank agaric from western North America

Baeospora occidentalis is described as a new species associated with melting snow in montane coniferous forests of the western USA. The species is spring-fruiting and is characterized by a long tapering pseudorhiza covered with white basal rhizomorphs which extends deeply into the needle litter or woody debris. It possesses a multiallelic, tetrapolar mating system. Monokaryotic mycelia produce arthroconidia.     

The tadpole of Scinax aromothyella (Anura: Hylidae) from Uruguay

We describe the tadpole of Scinax aromothyella from the surroundings of Quebrada de los Cuervos, Departamento de Treinta y Tres, Uruguay. It shares with other larvae of the Scinax catharinae clade the slightly depressed body, a dextral vent tube that reaches the free margin of the ventral fin, and the oral disc with a dorsal gap in the marginal row of papillae and with a concave posterior edge. It is most similar to the tadpole of Scinax berthae, from which it differs in the larger total length of S. aromothyella.

Describimos la larva de Scinax aromothyella de los alrededores de la Quebrada de los Cuervos, Departamento de Treinta y Tres, Uruguay. Comparte con las larvas de otras especies del clado de Scinax catharinae el tener el cuerpo levemente deprimido, el tubo proctodeal dextro que alcanza el borde libre de la aleta ventral, y el disco oral con un claro rostral en la hilera de papilas marginales y con su borde posterior cóncavo. Es muy parecida a la larva de Scinax berthae, de la que difiere en la mayor longitud total de S. aromothyella.