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We describe a new species of salamander of Bolitoglossa (Oaxakia) Parra-Olea, García-París and Wake, 2004 from the cloud forests of the central portion of the Sierra Madre del Sur highlands in the Mexican state of Guerrero. Bolitoglossa coaxtlahuacana sp. nov. is currently known only from the type locality and can be differentiated from other members of the group by morphological, coloration, and molecular evidence. With the description of this new taxon, the number of species in the subgenus Oaxakia increases to six.

Senticolis triaspis is a widespread polytypic colubrid snake that ranges from the southwestern United States southward along the Pacific Coast and part of the Atlantic Coast of Mexico to Costa Rica. Three subspecies have been described based on differences in color pattern and scutellation: S. t. intermedia, S. t. mutabilis, and S. t. triaspis. The last taxonomic revision was completed in 1960. Here, we present an integrative taxonomic analysis of geographic variation using multiple sources of evidence: mitochondrial DNA (817 bp ND4 from 62 samples), traditional morphology (meristic and mensural characters), geometric morphometrics of head shape, and bioclimatic estimates of environmental niche similarity. Molecular data revealed two deeply divergent mitochondrial lineages corresponding to northern and southern clades and eight well-supported clades within these two main groups. Head shape and niche models also showed north–south differences, while traditional morphological analyses did not discriminate among mtDNA lineages. Thus, our study suggests there are at least two candidate species within Senticolis triaspis based on the mtDNA divergence, differences in head shape, and non-overlapping ecological niches. However, we refrain from making taxonomic recommendations pending the addition of nuclear DNA sequence data, finer sampling at contact zones, and additional morphological data; these data are warranted to provide a more robust, stable species delimitation.

We assessed the effect of temperature on subclinical Batrachochytrium dendrobatidis (Bd) infection in three species of plethodontids. Collected individuals were tested for Bd in the field during the dry and rainy season and randomly assigned to 15° and 18°C treatments for 30 days. We collected 129 salamanders, of these nine individuals tested positive for Bd in the field. At the two temperature trials, 12 individuals that were Bd-negative in the field, tested positive for Bd. Near the end of the temperature trials, 18 of 21 Bd-positive individuals tested negative for Bd. Three individuals that were Bd positive in the field and assigned to the 18°C trial died during the experiment. Our results suggest that at 15°C the most of plethodontids present subclinical infection, whereas at higher temperatures, Bd infection can increase to detectable levels. The processes underlying plethodontids’s recovery from Bd infection warrants further study.

Frogs of the genus Eleutherodactylus are direct developing frogs grouped into five subgenera and 192 species, with a geographic distribution primarily centered in the Caribbean (Padial et al. 2014). Eleutherodactylus species inhabit a variety of environments such as tropical and temperate forests, and scrub, where they occupy different microhabitats including caves, floors rich in leaf litter, cracks and cavities of limestone and volcanic outcrops (Reyes-Velasco et al. 2015). Mexico harbors 33 species of Eleutherodactylus (AmphibiaWeb 2018), most of them distributed in central-western and southwestern Mexico (Reyes-Velasco et al. 2015).

Only two species of Ixalotriton, I. niger and I. parvus, are currently known, and both are endemic to small regions of Chiapas, Mexico. An additional population of black Ixalotriton has recently been reported from caves on Cerro Baul, near the only known locality of I. parvus. We conducted morphological and molecular analyses of animals from the new population and I. niger to determine whether they are conspecific. Animals from the Cerro Baul population resemble I. niger morphologically, but they are somewhat divergent in mitochondrial sequence. We assign them to I. niger because of the lack of diagnostic morphological differences. This expands the range of I. niger to a second locality and puts the two species of Ixalotriton in sympatry, although they are separated by microhabitat. Protection for the new population is urgently needed, given declines in abundance of I. niger at the type locality.

A new species of treefrog from the genus Charadrahyla is described from the cloud forest of western Sierra Madre del Sur of Oaxaca, Mexico. Charadrahyla sakbah sp. nov., is distinguished from the rest of the species in the genus by the large body size (81.15–85.75 mm and 67.91–73.21 mm in adult females and males respectively), axillary membrane, adult males with hypertrophied webbings between toes I and II, nuptial excrescences, one enlarged conical tubercle on either side of vent, vocal slits absent, and sexual dimorphism in the snout shape in dorsal profile (rounded and acuminate in females and males respectively). The hypertrophied webbings are a unique character among other hylids of Middle America, and are only present in C. trux, C. tecuani and the species described herein. These three species inhabit the cloud forest of the Sierra Madre del Sur, and are probably closely related. However, more detailed phylogenetic analyses are needed to define the internal relationships of the genus. The cloud forest in the Sierra Madre del Sur continues to be known for a high number of endemic species. However, the cloud forest faces several threats due to its limited distribution that make it a priority ecosystem for conservation.

Chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal), is an infectious disease of amphibians linked to mass amphibian die-offs worldwide. In this study, we sampled four dead and dying individuals of Ambystoma altamirani and Lithobates montezumae to detect the presence of Bd and Bsal. By real-time PCR (qPCR) and histopathology methods, we found the presence of Bd and the absence of Bsal in all individuals sampled. Our study indicates that chytridiomycosis may act as a threat for these species and highlight that future surveys are urgently needed to evaluate the Bd infection on populations of A. altamirani and L. montezumae.

While salamanders have a predominantly north-temperate distribution, one of the most stunning radiations of species occurred in the only group to significantly penetrate the tropics, the bolitoglossines. Biogeographic hypotheses for the group have evolved as a result of the discovery of new species and lineages, from approximately 30 species in a single genus in 1926 to nearly 300 species in 14 genera today. Molecular phylogenies provide an important tool with which to test long-standing biogeographic hypotheses. Divergence dating analyses and parametric biogeographic analyses, together with a changing understanding of the taxonomy of the bolitoglossines and new geological evidence from Mesoamerica, call into question several long-standing hypotheses related to the arrival and diversification of the bolitoglossines in Central and South America. We briefly review the geology of Mesoamerica, with an emphasis on regions of high salamander diversity, and discuss how molecular phylogenies and new species disco...

A new species of Craugastor (Anura: Craugastoridae) from the montane rainforest of the Cordillera de Talamanca, Costa Rica. A new dirt frog of the Craugastor podiciferus Species Group is described from Costa Rica; it is restricted to elevations between 2330 and 2700 m a.s.l. in the montane rainforest of the Cordillera de Talamanca. Analysis of DNA sequences of the mitochondrial 16S rRNA (16S) and cytochrome oxidase I (COI) genes reveals a distinct lineage within the C. podiciferus Species Group. Additional morphological and morphometric analyses support the distinctiveness of this lineage that is described as a new species herein. The species is distinguished from other members of the C. podiciferus Species Group by its unique coloration: a violet-brown to blackish brown venter with white pigment forming blotches, and dark brown palmar surfaces with prominent white folds between subarticular tubercles in the adults. The genetic divergence of the species from other members of the C. podiciferus Species Group is signifcant (higher than 9.2% in 16S and 13.3% in COI). Although not closely related, it resembles C. podiciferus morphologically, a species that also inhabits montane rainforest. The discovery of this new species highlights the importance of montane rainforest as a center of species richness and endemism.

Author(s): Rovito, SM; Parra-Olea, G; Recuero, E; Wake, DB | Abstract: The Neotropical bolitoglossine salamanders represent an impressive adaptive radiation, comprising roughly 40% of global salamander species diversity. Despite decades of morphological studies and molecular work, a robust multilocus phylogenetic hypothesis based on DNA sequence data is lacking for the group. We estimated species trees based on multilocus nuclear and mitochondrial data for all major lineages within the bolitoglossines, and used our new phylogenetic hypothesis to test traditional biogeographical scenarios and hypotheses of morphological evolution in the group. In contrast to previous phylogenies, our results place all Central American endemic genera in a single clade and suggest that Central America played a critical role in the early biogeographical history of the group. The large, predominantly Mexican genus Pseudoeurycea is paraphyletic, and analyses of the nuclear data place two lineages of Pseudoeurycea as the sister group of Bolitoglossa. Our phylogeny reveals extensive homoplasy in morphological characters, which may be the result of truncation or alteration of a shared developmental trajectory. We used our phylogenetic results to revise the taxonomy of the genus Pseudoeurycea.

Author(s): Rovito, SM; Vasquez-Almazan, CR; Papenfuss, TJ; Parra-Olea, G; Wake, DB | Abstract: The cloud forests of Mesoamerica are notable for their high endemism, and plethodontid salamanders provide a striking example of divergence and microendemism across cloud forest blocks at a regional level. Salamanders that make use of arboreal bromeliad microhabitats in the cloud forest appear to be especially prone to divergence driven by natural habitat fragmentation, and are expected to show high endemism at small spatial scales. We use a multilocus dataset to investigate the biogeographic history and relationships among species of a small genus of salamander, Cryptotriton, restricted to the cloud forests of Nuclear Central America. We use a morphological data set along with a coalescent species delimitation method to reveal the presence of at least one undescribed species from an isolated cloud forest in eastern Guatemala. Biogeographic analyses show that Cryptotriton has a different biogeographic history than another clade of cloud forest-restricted salamanders in the same region, perhaps indicating that each genus restricted the spatial expansion and diversification of the other through preemptive occupancy. Our results suggest that isolation across relatively short geographic distances has led to range fragmentation and deep divergence between species. Exploration of remaining patches of cloud forest likely will continue to reveal undetected diversity.

We describe a new species of Pseudoeurycea from the cloud forests of Huatusco in the state of Veracruz, México. This species belongs to the P. cephalica complex. Pseudoeurycea cafetalera sp. nov. is sister to the clade formed by P. cephalica and P. quetzalanensis. The new species is diagnosed by a stout body, long stout legs, short digits, somewhat webbed hands and feet, a distinctive coloration and by divergent mitochondrial DNA sequences.

Species with highly restricted distributions are vulnerable to extinction, and modification of natural habitats within their small ranges is a primary threat to their persistence. Expansion of urban development significantly impacts natural habitats and, therefore, threatens local diversity. The Mexican axolotl, Ambystoma mexicanum, is a strictly aquatic species that persists currently in two highly threatened and isolated populations. The current habitat remaining for these species are remnants of a historically extensive lacustrine system that occupied the entire Valley of Mexico, but has been destroyed by the growth of Mexico City. Unexpectedly, a third viable population of axolotls has been found in Chapultepec Park, a public recreational area in the heart of Mexico City. Phylogenetic and haplotype network analyses of mitochondrial DNA sequences confirmed low genetic differentiation and a recurrent lack of monophyly in many of the taxa belonging to the Ambystoma tigrinum species group, including A. me...

Abstract Amphibians are greatly affected by diversity loss and recent declines in amphibian populations are well documented. One of the proposed causes of such declines, UV-B radiation, has been reported to induce lethal and sub-lethal effects on different ontogenetic phases of development. Of these phases, the embryo stage is likely the most vulnerable. We used an experimental approach to test for the effects of UV-B radiation on embryo development of the Mexican axolotl, Ambystoma mexicanum. Recently, its natural populations experienced a 60% decline. We conducted experimental trials over the course of a year in which we exposed A. mexicanum eggs to 3 different treatments of varying UV-B ray intensities. Our results indicate that environmental UV-B radiation in Mexico City adversely affects the embryos of the Mexican axolotl at particular times of the year. The embryos exposed to 100% UV-B radiation had strikingly more deformities (mostly blisters and edemas), shorter periods of embryonic development, smaller hatchling size, and experienced increased mortality in comparison with embryos that were partially or totally protected from UV-B rays. The breeding season of A. mexicanum coincides with the time of the year in which the effects of UV-B radiation are most harmful (February through April). The observed negative effects of UV-B rays could act synergistically with chemical pollutants, exotic species, and pathogens to yield the negative population trends currently observed in this endemic Mexican amphibian.

La revision de los ejemplares de la familia Meloidae de la pequena coleccion entomologica del ECOSUR en San Cristobal de las Casas (Chiapas, Mexico), acompanada del examen de material chiapaneco del genero Epicauta de la Coleccion Nacional de Insectos (CNIN-IBUNAM, Instituto de Biologia, UNAM, Mexico), material de Meloidae del Museo Hungaro de Historia Natural (HMNH, Magyar Termeszettudomanyi Muzeum, Budapest) y de la coleccion Marco A. Bologna (MAB, Universita degli Studi Roma Tre, Italia), permite documentar por primera vez la presencia en el Estado de Chiapas de: Epicauta diana Pinto, 1991; Epicauta rufipennis (Chevrolat, 1834); Epicauta forticornis (Haag-Rutenberg, 1880); Epicauta distorta (Champion, 1892); Meloe tropicus Motschulsky, 1856; Denierota kraatzi (Haag-Rutenberg, 1880); Pyrota decorata (Haag-Rutenberg, 1880); Cissites auriculata (Champion, 1892) y Tetraonyx frontalis Chevrolat, 1833. De entre estas especies destacan las citas de M. tropicus que permiten confirmar la presencia de la especie en Mexico y la de D. kraatzi que constituye el primer registro preciso del genero Denierota en Mexico. Por otra parte, la revision del material utilizado por Z. Kaszab en la descripcion del genero Denierota (HNHM), acompanado del material de la coleccion M. Bologna y el examen de fotografias detalladas de los tipos de los dos taxones incluidos en el genero Denierota, Lytta sanguineoguttata Haag-Rutenberg, 1880 y Lytta kraatzi Haag-Rutenberg, 1880, del Zoologische Staatssammlung de Munich (Alemania), nos permiten concluir que el genero Denierota incluye una unica especie descrita y nos permite formalizar la sinonimia de L. sanguineoguttata con L. kraatzi, resolviendo el largo y debatido problema taxonomico que suscitaba la identidad de L. kraatzi y el problema secundario de falta de localidad-tipo (�patria ignota�) para esta especie.

94 páginas., [ES] Se presenta un catálogo taxonómico de los representantes mexicanos de la familia Meloidae que incluye un listado revisado de sinonimias, localidades típicas y registros geográficos publicados de cada una de las especies. La fauna mexicana incluye en la actualidad 255 especies vivientes y una fósil, distribuidas en 21 géneros de las subfamilias Meloinae, Nemognathinae y Tetraonycinae. En el último catálogo general, Blackwelder (1945) recogió la presencia en México de 160 especies de esta familia, casi 100 especies menos de las que se conocen en la actualidad y sin embargo, la cifra actual parece encontrarse aún lejos de la real, ya que existen muchas especies ampliamente distribuidas al norte de la frontera con los Estados Unidos cuya presencia es muy probable en territorio mexicano. En cuanto a la taxonomía y nomenclatura de las especies, en este catálogo se propone el uso de los nombres Epicauta dugesi Werner, 1957 y Tegrodera erosa extincta Beauregard, 1890; se incluyen tres sinonimias nuevas de Nemognatha chrysomeloides (Linnaeus, 1763) (N. atra Beauregard, 1890; N. pallidicollis Beauregard, 1890 y N. violacea Beauregard, 1890) y otra de E. dugesi (Epicauta tamara Adams & Selander, 1979); se designa lectotipo para Lytta koltzei var. minor Haag-Rutenberg, 1880 con el propósito de solucionar el problema taxonómico generado tras la designación inválida de lectotipo de L. k. var. cyanescens; y finalmente se consideran como especies posiblemente a excluir del listado de Meloidae de México a Cissites maculata (Swederus, 1787) y Tetraonyx (Tetraonyx) bimaculatus (Klug, 1825)., [EN] A comprehensive taxonomic catalogue of the Mexican representatives of the family Meloidae is presented. The catalogue includes a revised synonymical list including type localities and published geographical records for all known species. The Mexican Fauna of Meloidae currently includes 255 extant species, plus one only known from the fossil conrecord, arranged in 21 genera within the subfamilies Meloinae, Nemognathinae and Tetraonycinae. The last comprehensive catalogue published (Blackwelder, 1945) recorded the presence of 160 species of Meloidae in México, almost 100 species less than the current known number. However the current number of species seems to be far below the actual number, since many species widely distributed along the northern border, within the United States, are likely to be found also in Mexico. Regarding taxonomic and nomenclatural changes, in this catalogue we propose the use of the names Epicauta dugesi Werner, 1957 and Tegrodera erosa extincta Beauregard, 1890; we propose three new synonymies for Nemognatha chrysomeloides (Linnaeus, 1763) (N. atra Beauregard, 1890; N. pallidicollis Beauregard, 1890 and N. violacea Beauregard, 1890) and one for E. dugesi (Epicauta tamara Adams & Selander, 1979); we designate lectotype for Lytta koltzei var. minor Haag-Rutenberg, 1880 with the goal of resolving the taxonomic problem generated by the previous invalid designation of lectotype for L. k. var. cyanescens; and finally we consider Cissites maculata (Swederus, 1787) and Tetraonyx (Tetraonyx) bimaculatus (Klug, 1825) as species to be possibly excluded from the Mexican checklist., Este trabajo ha contado para su realización con los proyectos CGL2004-04680-C10-10/BOS y CGL2007-64621 del Ministerio de Educación y Ciencia, lo que nos ha facilitado el apoyo logístico necesario. La visita a la colección del Magyar Természettudomány Múzeum (HNHM) en Budapest ha sido financiada por el proyecto Synthesys «European Commission´s Research Infrastructure Action».

9 páginas, 2 figuras et al.., [EN] We describe two new species of salamanders of the genus Pseudoeurycea from mountains in the northern part of the state of Oaxaca, Mexico. Pseudoeurycea papenfussi, a large, muscular member of the P. gadovii group, occurs near the peaks (just below 3000 m) of the highest mountains of the Sierra de Jua´rez. It is related to P. smithi, a more southerly species, and possibly to P. aquatica, another species from Oaxaca. Pseudoeurycea obesa, a rotund member of the P. leprosa group, is known only from the type locality in the Sierra Mazateca at the northernmost extremity of Oaxaca. It is related to P. werleri and P. mystax, which are known from more southern parts of Oaxaca. These descriptions bring to 27 the number of species of salamanders known from Oaxaca. Most of these species are endemic to the state and are known only from regions that are undergoing rapid habitat modification and destruction., [ES] Describimos dos especies nuevas de salamandras del genero Pseudoeurycea de las montañas del norte del Estado de Oaxaca, Mexico. Pseudoeurycea papenfussi es una especie de gran tamaño, de aspecto musculoso, incluida en el grupo de P. gadovii, que se encuentra cerca de las cumbres (justo por debajo de los 3000 m) de las montañas mas altas de la Sierra de Juarez. Esta relacionada con P. smithi, que se encuentra en regiones mas meridionales, y posiblemente con P. aquatica, tambien de Oaxaca. Pseudoeurycea obesa, es una especie rechoncha del grupo de P. leprosa, que unicamente se conoce la localidad tıpica en la Sierra Mazateca del extremo noroccidental de Oaxaca., This work has been partially funded by the David Rockefeller Center for Latin American Studies, Harvard University (to JH), UC-MEXUS CN-02–74 (GP-O and DBW), SEMAMATCONACYT 2002-C01–0015 (GP-O), CSIC-CONACYT 2004MX0011 (GP-O and MG-P), and by NSF EF-0334846 ( JH) and EF-0334939 (DBW). SEMARNAT provided collecting permits (FAUT.0106, to GP-O). Animal use was approved by the University of California, Berkeley, protocol R093–0205 (to DBW).

The genus Chiropterotriton contains only 12 described species but includes a rich variety of morphological and ecological forms ranging from diminutive to large cave-dwelling species, as well as a number of terrestrial and arboreal forms. Although morphological diversification has taken place during the evolution of this genus, morphological stasis and parallelism also characterize the evolution of this group, generating complexes of cryptic species. I obtained sequences of the 16S ribosomal mtDNA gene from most of the species. Mitochondrial DNA shows great diversification, with genetic divergence among taxa as high as 12.5%. The 531-bp mtDNA data matrix contained 121 parsimony-informative characters. Basal relationships are poorly supported by maximum parsimony analyses. There is, however, support for a clade that includes all of the samples of the C. chiropterus group. The maximum-likelihood and Bayesian topologies differ from maximum-parsimony topologies mainly in the arrangement of the basal relationships. Based on the results, the genus Chiropterotriton comprises 12 species with available names: C. arboreus, C. chiropterus, C. chondrostega, C. cracens, C. dimidiatus, C. lavae, C. magnipes, C. mosaueri, C. multidentatus, C. orculus, C. priscus, and C. terrestris, plus 7 additional undescribed species for which allozyme and mitochondrial data sets are congruent.

In Mexico City, native and exotic amphibians are commonly sold through the pet trade. This study investigates the presence of Batrachochytrium dendrobatidis (Bd) in native amphibians being sold at two commercial markets and at a herpetarium in Mexico City. A total of 238 individuals (6 genera and 12 species) were tested for Bd using real-time polymerase chain reaction (PCR) analysis. There were 197 Bd-positive individuals (prevalence 82%) from five species of amphibians. Hyla eximia from the markets had very high Bd prevalence (100%; 76/76 and 99%; 88/89) but those from the herpetarium were Bd negative (0/12). Ambystoma mexicanum from the herpetarium also had a high Bd-positive prevalence (80%; 28/35). Though A. mexicanum is nearly extinct in the wild, a commercial market continues to flourish through the pet trade. Now that captive colonies of A. mexicanum are currently used for reintroduction programs, the authors recommend quarantine to reduce spread of Bd via movement of infected animals in the trade and between colonies and via disposal of wastewater from captive collections.

The Bolitoglossa macrinii species group (restricted geographically to southern Oaxaca and southwestern Guerrero, Mexico) is a monophyletic assemblage of five species, B. macrinii, Bolitoglossa riletti, Bolitoglossa hermosa, Bolitoglossa oaxacensis sp. nov., and Bolitoglossa zapoteca sp. nov. DNA sequences totaling 1164 base pairs for the mitochondrial genes 16S ribosomal RNA and cytochrome b were analyzed to generate a phylogenetic hypothesis for the relationships within the group. Our hypothesis is in agreement with previous morphological and allozyme analyses. Divergence within the group is great (to 18.6% for cytochrome b, to 7.0% for 16S rRNA) and two clades are well supported: one including B. riletti, B. hermosa, and B. zapoteca and the other including B. macrinii and B. oaxacensis. These clades likely diverged beginning in mid-Miocene times. We describe two new species, B. oaxacensis, for inland Oaxacan populations previously assigned to B. macrinii, and B. zapoteca for the easternmost pop...

Chiropterotriton is a relatively small genus that comprises 15 species with great morphological and ecological diversity. In previous studies, molecular data provided evidence for a considerable number of species that remain undescribed. In this study, we describe one new species, Chiropterotriton chico sp. nov. based on molecular and morphological characters. We present mtDNA phylogenetic analyses using Bayesian inference and maximum likelihood that include all described and several undescribed species. Morphometric data from eight recognized species provide evidence for the distinctiveness of the new taxon. Description of this new species adds to the already high salamander diversity of the state of Hidalgo, which is an important area for the diversification of the genus.

Two species of horned lizards, Phrynosoma braconnieri and P. taurus, are endemic to Mexico and inhabit medium and high-elevation sites in the states of Oaxaca, Guerrero, and Puebla. We compiled information on distribution and reproductive cycle for these two species from the literature and from an examination of speci- mens in systematic collections. Our study confirms a viviparous mode of reproduc- tion for both species and suggests that their reproductive cycles may be different from that observed in other viviparous Phrynosoma. Specifically, embryonic devel- opment occurs during the late fall and winter months, with a parturition date in early spring. In contrast, other viviparous horned lizards gestate during the spring and summer months and give birth to their young in the late summer. Examining the phylogenetic distribution of reproductive modes in this genus suggests that two high-elevation clades of horned lizards have independently evolved viviparity from an oviparous ancestor, yet each of these clades has evolved a distinct reproductive cycle. Las especies endemicas de Mexico Phrynosoma braconnieri y P. taurus habitan ele- vaciones intermedias y altas en los estados de Oaxaca, Guerrero y Puebla. En este trabajo revisamos ejemplares de colecciones y recopilamos informacion bibliograf- ica sobre la distribucion y ciclos reproductivos de estas dos especies. Este estudio confirma la existencia de un modo de reproduccion viviparo en ambas especies, y sugiere que su ciclo reproductivo difiere del observado en otras especies viviparas de Phrynosoma. En particular, en P. braconnieri y P. taurus el desarrollo embrionario se lleva a cabo durante el final del otono y principios de invierno dandose el parto al principio de la primavera. En contraste, en otras especies viviparas de Phrynosoma la gestacion se realiza durante la primavera y el verano mientras que el parto ocurre en el verano tardio. La revision de la distribucion filogenetica de los modos reprod- uctivos en este genero, sugiere que dos clados de Phrynosoma que viven en eleva- ciones altas han adquirido independientemente un modo viviparo a partir de un ancestro oviparo. Sin embargo, cada uno de estos clados ha evolucionado un ciclo reproductivo particular.

In this report, we describe a new species of the Craugastor podiciferus species group from the premontane forest of the Pacific versant along the Costa Rican-Panamanian border. Mitochondrial DNA and karyotype analyses previously showed a marked genetic divergence between populations of the premontane forest of the Fila Costena and the lowlands South Pacific Costa Rica near Panama. Analyses of the mitochondrial DNA sequences and the morphological variation revealed significant differences between the populations of the premontane forest relative to the other populations of C. stejnegerianus , including the type locality. We recognize these premontane populations as a new species and show that they differ from the typical C. stejnegerianus in the coloration of the venter, the head and the body proportions, and mtDNA divergence. With the addition of this new species, the C. podiciferus species group now contains nine species.

We describe a new species of Bolitoglossa (Nanotriton) from the Sierra de Juárez and Sierra Mixe of Oaxaca, Mexico. Bolitoglossa chinanteca sp. n. is distinguished from the three other species in the subgenus Nanotriton by its more robust body, bysubstantial numbers of maxillary teeth and differences in relative head width, foot width, and limb length. The new species occurs in sympatry with Bolitoglossa (Nanotriton) rufescens at the type locality. The description of another species of salamander from the Sierra de Juárez is noteworthy, given the already high plethodontid salamander species richness of the region.

Salamanders of the Pseudoeurycea bellii complex are widespread in Me´ xico north and west of the Isthmus of Tehuantepec. They are the largest terrestrial salamanders and have distinctive color patterns consisting of a general black ground color with strikingly bold red-orange marks in different patterns on the dorsal surface. At present three species are recognized: P. bellii (widespread, with two subspecies), P. gigantea (restricted to a small area of eastern Me´ xico), and P. naucampatepetl (known only from the vicinity of the type locality in west-central Veracruz). A phylogenetic analysis based on two mitochondrial genes (cytochrome b and 16S RNA) finds support for three main clades, one including P. gigantea and P. naucampatepetl, another including the Oaxacan samples, and a third including P. bellii. New morphological data, DNA sequences, and limited allozymic information provide evidence that the Oaxacan clade comprises two species. The name P. boneti is resurrected from synonymy and applies to northern Oaxacan populations, while a new species is described from extreme western Oaxaca at elevations lower than have been recorded elsewhere for members of the complex., SEMARNAT provided collecting permits. Studies were financed in part by grants UC-MEXUS (CN-02-74), and Semarnat-Conacyt (SEMARNAT- 2002-C01-0015)., 14 páginas, 3 figuras, 2 tables et al.

7 páginas, 3 figuras et al.., A new species of Pseudoeurycea is described from cloud forests of the Sierra Madre Oriental of Puebla, México. The new species is distinguished from all other Pseudoeurycea by its small size, stout body, short tail, large nostrils, presence of characteristic glandular convergent ridges on the pelvic region and the tail, and by its distinctive limb structure, with very small hands and feet that are extensively webbed and bear prominent but short and pointy middle digits. The only apparent close relative of this species is P. praecellens, from which it differs by the position and distribution of the dorsal and caudal glands, body proportions, nostril size and coloration. All specimens of the new species were found in cloud forest, under a canopy of Liquidambar, Quercus, and arborescent ferns, as well as in a coffee grove. The elevational range for the species is narrow, between 905 and 1400 m, unusually low elevations for Pseudoeurycea., SEMARNAT provided the necessary collecting permits. Partial support for field work was provided by CONABIO (FB444/L283/97 ) to G. Gutierrez-Mayén, NSF (DEB 0102383) to J. Campbell, and by the joint project CSIC-CONACyT (Spain-México) 2004MX0011 to GP-O and MG-P.

Plethodontid salamanders represent a group of amphibians that show a great evolutionary diversification in México, however no study of their helminth parasites had been conducted thus far. In this paper, we describe Cosmocerca acanthurum n. sp. (Nematoda: Cosmocercidae) from the intestine of the plethodontid salamanders Pseudoeurycea leprosa and Chiropterotriton orculus from Llano Grande and Texcalyacac, Estado de México, in Central México. Cosmocerca acanthurum n. sp. is easily distinguished from all other species of Cosmocerca in that females possess a uniquely spined tail, a character no seen in congeners. In addition, we compiled all the information of helminth parasites of plethodontid salamanders, and we present it in the form of a checklist of both parasite-host, and host-parasite. A brief analysis of the helminth parasite species composition is presented regarding life-history and development characteristics of plethodontids.