Dietary supplementation with integral chia and flax flours ameliorates systemic inflammation.

INTRODUCTION: Chia and flax seeds are rich in alphalinolenic acid (ALA), which is bioconverted into the active derivatives eicosapentaenoic (EPA) and docosahexaenoic (DHA) having multiple beneficial effects. However, there is limited knowledge about the antiinflammatory effects of chia and flax integral flours diets rich in ALA. OBJECTIVE: The study aimed to evaluate the antiinflammatory effect of dietary supplementation with integral chia and flax flours in a murine model of LPSinduced systemic inflammation. METHODS: Balb/c mice were distributed into three groups: diet A (control), diet B (supplemented with integral chia flour), and diet C (supplemented with integral flax flour). Nutritional, hematological, and biochemical determinations were performed. ALA, EPA, and DHA were assessed by GC-MS in the liver, brain, cardiac and skeletal muscles. NF-kB immunoassays were performed in kidney, liver, and peritoneal macrophages, respectively. The phagocytic capacity was determined in peritoneal macrophages and the expression of the pro- and anti-inflammatory cytokines was assessed by RT-qPCR in the kidney, liver, and spleen. RESULTS: Diets B and C exhibited optimal nutritional adequacy and caused increased levels of ALA, EPA, and DHA in critical tissues compared to the control. The phagocytic capacity of murine peritoneal macrophages (p< 0.01) and IL-10 transcription increased, whereas the expression of NF-κB, IL-1Β, IL-6, and TNF-α decreased in animals fed both experimental diets. CONCLUSIONS: This work contributes to the current knowledge of the anti-inflammatory effects of chia and flax integral flours rich in ALA and reinforces the health advantages of their consumption.

Introducción: Las semillas de chía y lino son ricas en ácido alfa-linolénico (ALA), sus derivados activos eicosapentaenoico (EPA) y docosahexaenoico (DHA) ejercen probados efectos beneficiosos. Existe un conocimiento limitado sobre los efectos protectores de ambas semillas bajo la forma de harinas integrales, siendo de particular interés el efecto antiinflamatorio. OBJETIVO: El objetivo de este trabajo fue evaluar el efecto antiinflamatorio de la suplementación dietaria con harinas integrales de semillas de chía y lino en un modelo murino de inflamación sistémica inducido por LPS. Métodos: Ratones de la cepa Balb/c fueron distribuidos en tres grupos: dieta A (control), dieta B (suplementada con harina integral de chía) y dieta C (suplementada con harina integral de lino). Se efecturaron determinaciones nutricionales, hematológicas y bioquímicas. El contenido de ALA, EPA y DHA en hígado, cerebro, corazón y músculo esquelético se determinó por cromatografía GC-MS. Se realizó la inmunodetección de NF-kB en macrófagos peritoneales, riñón e hígado. Se determinó la capacidad fagocítica de macrófagos peritoneales y se evaluó la expresión de citoquinas pro y antiinflamatorias por RT-qPCR en riñón, hígado y bazo. RESULTADOS: Las dietas B y C mostraron una adecuación nutricional óptima y generaron niveles elevados de ALA, EPA y DHA en tejidos críticos. La capacidad fagocítica de los macrófagos peritoneales (p< 0.01) y la transcripción de IL-10 aumentó, mientras que la expresión de NF-κB, IL-1Β, IL-6 y TNF-α disminuyó en animales de los grupos B y C. CONCLUSIONES: Este trabajo contribuye al conocimiento actual de los efectos antiinflamatorios de ambas harinas integrales y refuerza los beneficios de su consumo.

Early gonadogenesis in Columba livia (birds: Columbiformes): Migration, colonization, and differentiation of germ cells.

In birds, primordial germ cells (PGCs) use the bloodstream to travel to a specific region, where the cells undergo extravasation followed by intrastromal migration to the gonadal crest for further colonization. Currently, DDX4, SSEA1, and Oct4 are used to identify germ cells. Other germline cell-associated molecules are N-cadherin, GnRHR, and 3ß hydroxysteroid dehydrogenase (3ßHSD), which have been used in mice and birds during gonadal development; however, its role in early gonadogenesis in birds is poorly described. This study aimed to evaluate the differential immunodetection of N-cadherin binding molecule, Oct4 pluripotency protein, GnRHR receptor, and 3ßHSD enzyme in Columba livia embryos during migration colonization of PGCs in the gonadal crest and early gonadogenesis. These markers were revealed by immunohistochemistry in histological preparations of C. livia corresponding to stages (S)15 to S40. Immunodetection of N-cadherin, Oct4, GnRHR, and 3ßHSD in the germ line of C. livia allowed the identification of PGCs in the yolk sac membrane at the level of the splanchnic mesoderm during migration to the genital crest and its colonization. In the same way, it was possible to characterize and localize PGCs during early gonadogenesis. This study in C. livia demonstrates that Oct4, N-cadherin, GNRHR, and 3ßHSD are immunodetected in PGCs and could be used as potential germline cell markers during cell migration out of blood vessels, colonization in the genital crest, and early gonadogenesis. Furthermore, this study could be used as a novel general model to understand the early gonadogenesis in altricial species.

Ongoing declines for the world's amphibians in the face of emerging threats.

Systematic assessments of species extinction risk at regular intervals are necessary for informing conservation action1,2. Ongoing developments in taxonomy, threatening processes and research further underscore the need for reassessment3,4. Here we report the findings of the second Global Amphibian Assessment, evaluating 8,011 species for the International Union for Conservation of Nature Red List of Threatened Species. We find that amphibians are the most threatened vertebrate class (40.7% of species are globally threatened). The updated Red List Index shows that the status of amphibians is deteriorating globally, particularly for salamanders and in the Neotropics. Disease and habitat loss drove 91% of status deteriorations between 1980 and 2004. Ongoing and projected climate change effects are now of increasing concern, driving 39% of status deteriorations since 2004, followed by habitat loss (37%). Although signs of species recoveries incentivize immediate conservation action, scaled-up investment is urgently needed to reverse the current trends.

Structural and histochemical aspects of the Gymnotus carapo tegument (Teleostei: Gymnotiformes).

The present study aims to structurally and histochemically characterize the Gymnotus carapo tegument. 30 specimens were captured and slaughtered by spinal section with anesthesia. The observation was carried out with a stereoscopic microscope and the body surface was photographed. Fragments of the dorsal, ventral and lateral region were fixed in Bouin's solution for 12 hours and subsequently preserved in 70% alcohol. They were subsequently observed in the scanning electron microscope (SEM). The preparation for SEM was performed following the standardized protocol. Histological preparations were made, and the cuts were colored with H-E, PAS and Coomassie Blue. The images were obtained in an Olympus BX41-ENUTV-4 microscope. From the observations in SEM a plain tegument with pores of different sizes could be evidenced. The scales of the different regions of the body have different ornaments. Microscopically it was composed of a stratified non-keratinized epithelium consisting of two types of morphologically distinct cells: epidermal cells and mucous cells (PAS-Commassie Blue positive). Under the epithelium there is a layer of dense irregular connective tissue with associated chromatophores and more deeply scales. These analyzes are the basis for future studies that will focus on elucidating the events related to integumentary healing in this species.

Comparative study of the gular gland of three species of Molossidae bats (Mammalia: Chiroptera) from South America.

The gular gland is a skin gland located in the suprasternal region of adult males of some bat families. Knowledge of the morphology and functional aspects of these gland types is often limited. This study aimed to describe the structure and composition of the gular glands of three molossid species (Eumops patagonicus, Molossus fluminensis and Molossus molossus) with respect to their reproductive activity and to define the mechanism involved in secretion release. Different histological, histochemical and immunohistochemical techniques were used to achieve these goals. The results revealed that the size and composition of this gland are variable and are mostly related to the lipid content during the reproductive season. The results also documented, for the first time, the occurrence of mechanoreceptors associated with the surface of the glandular duct by detecting an S100 protein, indicating that an external stimulus activates secretion. Previous studies on other species have classified the gland using obsolete criteria; hence, we adopted a new classification of adenomeres in this study. Moreover, we investigated the gland secretion mechanism previously proposed. This study defines the implications of this gland in the reproduction of this species. Our preliminary interpretation of the function of the gular gland is that it is a cutaneous exocrine gland activated by mechanoreceptors involved in the reproductive behaviour of the Molossidae family.

Environment rather than character displacement explains call evolution in glassfrogs.

The acoustic adaptation hypothesis (AAH) and ecological character displacement (ECD) are two potential mechanisms shaping call evolution that can predict opposite trends for the differentiation of signals. Under AAH, signals evolve to minimize environmental degradation and maximize detection against background noise, predicting call homogenization in similar habitats due to environmental constraints on signals. In contrast, ECD predicts greater differences in call traits of closely related taxa in sympatry because of selection against acoustic interference. We used comparative phylogenetic analyses to test the strength of these two selective mechanisms on the evolution of advertisement calls in glassfrogs, a highly diverse family of neotropical anurans. We found that, overall, acoustic adaptation to the environment may outweigh effects of species interactions. As expected under the AAH, temporal call parameters are correlated with vegetation density, but spectral call parameters had an unexpected inverse correlation with vegetation density, as well as an unexpected correlation with temperature. We detected call convergence among co-occurring species and also across multiple populations from the same species in different glassfrogs communities. Our results indicate that call convergence is common in glassfrogs, likely due to habitat filtering, while character displacement is relatively rare, suggesting that costs of signal similarity among related species may not drive divergent selection in all systems.

Factors Influencing Bacterial and Fungal Skin Communities of Montane Salamanders of Central Mexico.

Host microbial communities are increasingly seen as an important component of host health. In amphibians, the first land vertebrates that are threatened by a fungal skin disease globally, our understanding of the factors influencing the microbiome of amphibian skin remains incomplete because recent studies have focused almost exclusively on bacteria, and little information exists on fungal communities associated with wild amphibian species. In this study, we describe the effects of host phylogeny, climate, geographic distance, and infection with a fungal pathogen on the composition and structure of bacterial and fungal communities in seven tropical salamander species that occur in the Trans-Mexican Volcanic Belt of Central Mexico. We find that host phylogenetic relatedness is correlated with bacterial community composition while a composite climatic variable of temperature seasonality and precipitation is significantly associated with fungal community composition. We also estimated co-occurrence networks for bacterial and fungal taxa and found differences in the degree of connectivity and the distribution of negative associations between the two networks. Our results suggest that different factors may be responsible for structuring the bacterial and fungal communities of amphibian skin and that the inclusion of fungi in future studies could shed light on important functional interactions within the microbiome.

The fungal pathogen Batrachochytrium salamandrivorans is not detected in wild and captive amphibians from Mexico.

The recent emergence of the pathogen Batrachochytrium salamandrivorans (Bsal) is associated with rapid population declines of salamanders in Europe and its arrival to new areas could cause dramatic negative effects on other amphibian populations and species. Amphibian species, present in areas with high amphibian diversity such as Mexico, could be highly threatened due to the arrival of Bsal, particularly salamander species which are more vulnerable to chytridiomycosis caused by this pathogen. Thus, immediate surveillance is needed as a strategy to efficiently contend with this emerging infectious disease. In this study, we analyzed 490 wild and captive amphibians from 48 species across 76 sites in the North, Central, and South of Mexico to evaluate the presence of Bsal. Amphibians were sampled in sites with variable degrees of amphibian richness and suitability for Bsal according to previous studies. From the 76 sampling sites, 10 of them were located in areas with high amphibian richness and potential moderate to high Bsal habitat suitability. We did not detect Bsal in any of the samples, and no signs of the disease were observed in any individual at the time of sampling. Our results suggest that Bsal has not yet arrived at the sampled sites or could be at low prevalence within populations with low occurrence probability. This is the first study that evaluates the presence of Bsal in different regions and amphibian species in Mexico, which is the second most diverse country in salamander species in the world. We highlight the risk and the importance of continuing surveillance of Bsal in Mexico and discuss control strategies to avoid the introduction and spread of Bsal in the country.

Comparative Analysis of Skin Bacterial Diversity and Its Potential Antifungal Function Between Desert and Pine Forest Populations of Boreal Toads Anaxyrus boreas.

The skin microbiome in amphibians has gained a lot of attention as some of its members play a protective role against pathogens such as the fungus Batrachochytrium dendrobatidis (Bd). The composition of skin bacterial communities has been suggested as one of the factors explaining differences in susceptibility to Bd among amphibian species and populations. The boreal toad Anaxyrus boreas is known to be susceptible to Bd, and severe population declines in its southeastern range have been documented. However, throughout A. boreas distribution, populations present differences in susceptibility to Bd infections which may be associated with differences in skin microbial diversity. This study compared the skin bacterial diversity and Bd infection levels of A. boreas in one desert population and one pine forest population from Baja California, Mexico. We found that desert and pine forest toad populations exhibit differences in skin bacterial community structure but show similar Bd infection levels. Using a predictive method, we found that the abundance of bacteria with potential Bd-inhibitory properties differed between uninfected and infected individuals but not between populations. Our data suggest that several bacteria in the skin community may be offering protection from Bd infections in these A. boreas populations. This study provides foundational evidence for future studies seeking to understand the skin-microbial variation among boreal toads' populations and its relation with Bd susceptibility.

Genetic variation of Batrachochytrium dendrobatidis is linked to skin bacterial diversity in the Pacific treefrog Hyliola regilla (hypochondriaca).

Symbiotic bacterial communities are crucial to combating infections and contribute to host health. The amphibian skin microbiome plays an important role in protecting their hosts against pathogens such as Batrachochytrium dendrobatidis (Bd), one of the causative agents of chytridiomycosis, which is responsible for dramatic amphibian population declines worldwide. Although symbiotic skin bacteria are known to inhibit Bd growth, an understanding of the relationship between Bd genetic variability, environmental conditions, and skin bacterial communities is limited. Therefore, we examined the associations between Bd infection load, Bd genetic diversity and skin bacterial communities in five populations of Hyliola regilla (hypochondriaca) from environmentally contrasting sites in Baja California, Mexico. We observed differences in Bd genetics and infection load among sites and environments. Genetic analysis of Bd isolates revealed patterns of spatial structure corresponding to the five sites sampled. Amphibian skin bacterial diversity and community structure differed among environments and sites. Bacterial community composition was correlated with Bd genetic differences and infection load, with specific bacterial taxa enriched on infected and un-infected frogs. Our results indicate that skin-associated bacteria and Bd strains likely interact on the host skin, with consequences for microbial community structure and Bd infection intensity.

Batrachochytrium salamandrivorans' Amphibian Host Species and Invasion Range.

Batrachochytrium salamandrivorans (Bsal), a species related to the destructive pathogen Batrachochytrium dendrobatidis (Bd), was found and identified in Europe in 2013. Now, a decade later, a large amount of information is available. This includes data from studies in the field, reports of infection in captive amphibians, laboratory studies testing host susceptibility, and data from prospective studies that test for Bsal's presence in a location. We conducted a systematic review of the published literature and compiled a dataset of Bsal tests. We identified 67 species that have been reported positive for Bsal, 20 of which have a threatened conservation status. The distribution of species that have been found with infection encompasses 69 countries, highlighting the potential threat that Bsal poses. We point out where surveillance to detect Bsal have taken place and highlight areas that have not been well monitored. The large number of host species belonging to the families Plethodontidae and Salamandridae suggests a taxonomic pattern of susceptibility. Our results provide insight into the risk posed by Bsal and identifies vulnerable species and areas where surveillance is needed to fill existing knowledge gaps.

Gametogenesis and reproductive dynamics of Scinax acuminatus (Anura: Hylidae): morphological, histological and immunohistochemical analysis.

To characterize the reproductive biology of Scinax acuminatus and contribute to the natural history of this species, the morphology of the reproductive system of males and females was analyzed at anatomical, histological and immunohistochemical levels. The individuals were collected fortnightly between August and December (2016) and January to December (2018). The anatomy of the reproductive system was analyzed in a stereoscopic microscope, and histological preparations staining with hematoxylin-eosin and Masson's trichromic, PAS and Coomassie Blue was performed as well. To characterize the meiotic-active cells in the testes, immunostaining with the PCNA proliferation protein was performed. There were found females with ovaries with oocytes in different stages of maturity and post-ovulatory females. Males presented continuous spermatogenesis, which could be confirmed by the immunostaining of PCNA in spermatogonia during the cycle. The results of this work serve as a basis for the characterization of the reproductive cycle in S. acuminatus and provide background information on the analysis of spermatogenic activity by IHQ from the study of the immunodetection of the PCNA cell proliferation protein. Future studies will focus on the evaluation of cell death processes during the reproductive cycle in the studied species to compare with those obtained in terms of cell proliferation.

Geography is more important than life history in the recent diversification of the tiger salamander complex.

The North American tiger salamander species complex, including its best-known species, the Mexican axolotl, has long been a source of biological fascination. The complex exhibits a wide range of variation in developmental life history strategies, including populations and individuals that undergo metamorphosis; those able to forego metamorphosis and retain a larval, aquatic lifestyle (i.e., paedomorphosis); and those that do both. The evolution of a paedomorphic life history state is thought to lead to increased population genetic differentiation and ultimately reproductive isolation and speciation, but the degree to which it has shaped population- and species-level divergence is poorly understood. Using a large multilocus dataset from hundreds of samples across North America, we identified genetic clusters across the geographic range of the tiger salamander complex. These clusters often contain a mixture of paedomorphic and metamorphic taxa, indicating that geographic isolation has played a larger role in lineage divergence than paedomorphosis in this system. This conclusion is bolstered by geography-informed analyses indicating no effect of life history strategy on population genetic differentiation and by model-based population genetic analyses demonstrating gene flow between adjacent metamorphic and paedomorphic populations. This fine-scale genetic perspective on life history variation establishes a framework for understanding how plasticity, local adaptation, and gene flow contribute to lineage divergence. Many members of the tiger salamander complex are endangered, and the Mexican axolotl is an important model system in regenerative and biomedical research. Our results chart a course for more informed use of these taxa in experimental, ecological, and conservation research.

Inhibition of Batrachochytrium dendrobatidis Infection by Skin Bacterial Communities in Wild Amphibian Populations.

Skin-associated bacteria are known to inhibit infection by the fungal pathogen Batrachochytrium dendrobatidis (Bd) in amphibians. It has also been postulated that skin-associated bacterial community is related to Bd infection intensity. However, our understanding of host microbial dynamics and their importance in regulating Bd intensity is limited. We analyzed Bd infection and skin-associated bacteria from two amphibian species, the salamander Ambystoma rivulare and the frog Lithobates spectabilis that co-occurred in a tropical high-altitude site in central Mexico. Sixty-three percent of sampled salamander individuals and 80% of frog individuals tested positive for Bd. Overall, we registered 622 skin-associated bacterial genera, from which 73 are known to have Bd inhibitory effects. These inhibitory taxa represented a relative abundance of 50% in relation to total relative bacterial abundance. Our results indicated that, although sharing some bacterial taxa, bacterial community from the skin of both species was different in taxonomic composition and in relative abundance. Pseudomonas spp. and Stenotrophomonas spp. were among the five most abundant bacterial taxa of both species. Both bacterial taxa inhibit Bd infection. We detected that bacterial richness and relative abundance of inhibitory Bd bacteria were negatively related to intensity of Bd infection independent of species and seasons. Despite the high Bd prevalence in both host species, no dead or sick individuals were registered during field surveys. The relatively low levels of Bd load apparently do not compromise survival of host species. Therefore, our results suggested that individuals analyzed were able to survive and thrive under a dynamic relation with enzootic infections of Bd and their microbiota.

Anti-inflammatory activity of Nectandra angustifolia (Laurel Amarillo) ethanolic extract.

ETHNOPHARMACOLOGICAL RELEVANCE: Nectandra angustifolia belongs to the Lauraceae family and it is widely known in phytomedicine by local inhabitants of South America against various maladies. It is popularly used for the treatment of different types of inflammatory processes, like rheumatism, arthritis and its associated pain. AIM OF THE STUDY: To characterize the phytochemicals in an ethanolic extract of Nectandra angustifolia and to evaluate the total antioxidant content and its anti-inflammatory effect with multiparametric analyses through in vitro assays and an in vivo model. METHODS: Leaves and stems of Nectandra angustifolia were air-dried and an ethanolic extract (NaE) was further obtained. Total phenolic, flavonoid and tannin content were determined and the antioxidant activity was addressed by DPPH and FRAP assays. NaE was first analyzed by HPLC and then two tests were carried out as screening assays for anti-inflammatory activities: red blood cell membrane stabilization and protein denaturation. The non-cytotoxic concentration of NaE was determined for in vitro biological assays using RAW 264.7 (murine macrophages) cell cultures through cell counting with Trypan-blue and XTT assay. Subsequently, the cell cycle of RAW 264.7 cells exposed for 24 h to NaE was analyzed. Additionally, the anti-inflammatory capacity of NaE was evaluated by RT-qPCR of pro-inflammatory cytokines. Furthermore, NF-κB translocation was observed by confocal microscopy at different times. Finally, formalin-induced mice paw inflammation was used as an in vivo model. RESULTS: The chromatographic profile of NaE showed peaks compatible with flavonoids content. NaE exhibited better membrane stabilization effect on HRBC and protection of BSA denaturation than the standard drug (diclofenac). NaE diminished mRNA levels of pro-inflammatory cytokines when added 1-h prior LPS stimulation. Moreover, NaE prevented the translocation of NF-κB to the nucleus and in formalin-induced mice paw inflammation, reduced the edema and the stimulus of inflammatory phase. CONCLUSION: This study shows for the first time, that Nectandra angustifolia ethanolic extract has a high content of flavonoids and that possess antioxidant and anti-inflammatory biological properties as demonstrated by multiparametric analyses from in vitro assays and an in vivo model of inflammation.

Early presence of Batrachochytrium dendrobatidis in Mexico with a contemporary dominance of the global panzootic lineage.

Chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), is a devastating infectious disease of amphibians. Retrospective studies using museum vouchers and genetic samples supported the hypothesis that Bd colonized Mexico from North America and then continued to spread into Central and South America, where it led to dramatic losses in tropical amphibian biodiversity (the epizootic wave hypothesis). While these studies suggest that Bd has been in Mexico since the 1970s, information regarding the historical and contemporary occurrence of different pathogen genetic lineages across the country is limited. In the current study, we investigated the historical and contemporary patterns of Bd in Mexico. We combined the swabbing of historical museum vouchers and sampling of wild amphibians with a custom Bd genotyping assay to assess the presence, prevalence, and genetic diversity of Bd over time in Mexico. We found Bd-positive museum specimens from the late 1800s, far earlier than previous records and well before recent amphibian declines. With Bd genotypes from samples collected between 1975-2019, we observed a contemporary dominance of the global panzootic lineage in Mexico and report four genetic subpopulations and potential for admixture among these populations. The observed genetic variation did not have a clear geographic signature or provide clear support for the epizootic wave hypothesis. These results provide a framework for testing new questions regarding Bd invasions and their temporal relationship to observed amphibian declines in the Americas.

Ultrastructure of eggshell and embryological development of Salvator merianae (Squamata: Teiidae).

The objective of this study was to characterize the external morphology of Salvator meriane embryos in different stages of embryonic development and establish a relationship with the ultrastructure of the shell from oviductal transit to hatching. A total of 120 embryos were analyzed to describe their external morphology, and 78 eggs were used for the analysis of the shell. For embryonic development, the series was established according to the total length of the body. We established 40 embryonic stages from the primitive streak. In the early stages, the external morphological features are the C-shaped body, the maxillary, and mandibular fusion processes with the frontal process and the fusion of the forelimb with the digital plate. In the middle stages, the eyelid appears, and there are claws on the toes, cornification of fingers, and the onset of pigmentation. The last stage of embryonic development is characterized by the beginning of the formation of the scales, appear the toenails, and finalize the entire pigmentation. Regarding the relationship that exists with the ultrastructure of the egg during development, it was possible to observe a marked change in the composition of the shell and well-marked compaction during embryonic development, which may be related to the transport of calcium during embryonic ossification. Our results allowed us to show the complete sequence of embryonic development, determining the laying stage for this species. It was possible to establish a relationship with the ultrastructure of the eggshell from the oviductal transit to the moment of hatching.

Batracholandros salamandrae (Oxyuroidea: Pharyngodonidae) in Endemic Salamanders (Amphibia: Plethodontidae) of the Trans-Mexican Volcanic Belt: Host Range Wide Distribution or Cryptic Species Complex?

Salamanders of the tribe Bolitoglossini Hallowell are a highly diversified group of amphibians, and their helminth parasite fauna has been scarcely studied. Some species of plethodontid salamanders distributed along the Trans-Mexican Volcanic Belt, in central Mexico, were sampled, and their helminth parasites were recovered for taxonomic identification. Specimens of a pharyngodonid nematode from 2 species of bolitoglossines of the genus Pseudoeurycea Taylor were morphologically identified as Batracholandros salamandrae (Schad, 1960) Petter and Quentin, 1976. These specimens were studied in further detail through light and scanning electron microscopy and were sequenced for 2 ribosomal genes and 1 mitochondrial gene to test the hypothesis of whether B. salamandrae is a species widely distributed in salamanders across the Nearctic biogeographic region, or if it represents a cryptic species complex. Our molecular results revealed that these specimens consisted of 2 genetic lineages in concordance with host species, although with slight morphological differences among specimens in each of them. A thorough study, including the generation of molecular data from individuals from other areas of North America, and the examination of type specimens, is required to test the reliability of these morphological differences and to corroborate the species identity of the 2 genetic lineages.

Descriptions of five new species of the salamander genus Chiropterotriton (Caudata: Plethodontidae) from eastern Mexico and the status of three currently recognized taxa.

The genus Chiropterotriton is endemic to Mexico with a geographical distribution along the Sierra Madre Oriental, the Trans Mexican Volcanic Belt and the Sierra de Juárez. The recent use of molecular tools has shown that Mexico's amphibian diversity is highly underestimated, including a large number of cryptic, unnamed species. Chiropterotriton has 18 described species including terrestrial, arboreal and cave-dwelling species. In previous molecular studies, the presence of multiple undescribed species was evident. We present a phylogenetic hypothesis based on mitochondrial data, which includes all described species and six undescribed taxa. Based on the morphological analyses and, when available, combined with molecular data, we describe five new species of the genus; Chiropterotriton casasi sp. nov., C. ceronorum sp. nov., C. melipona sp. nov., C. perotensis sp. nov. and C. totonacus sp. nov. In addition, we redescribe two others: Chiropterotriton chiropterus and C. orculus, and provide a comparable account of one additional sympatric congener. This increases the number of species in the genus to 23, which represent a considerable component of Mexican plethodontid richness.