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We describe Bolitoglossa qeqom sp. nov. from an isolated cloud forest in Cerro Guachmalén, Alta Verapaz, Guatemala, based on multiple lines of evidence (morphological, molecular, and biogeographic data). This region comprises a mountain ridge without previous herpetological surveys. The new species is a large salamander with uniform purplish-black coloration and is distinguished by having relatively long legs with only one costal groove between adpressed limbs, numerous maxillary teeth, few vomerine teeth, only one phalange free of webbing in digit III of feet, and a relatively short tail. It is geographically closest to its sister clade of B. lincolni + B. franklini and the xeric Chixoy river canyon appears to be the major biogeographic barrier that isolated the new taxon. The cloud forest inhabited by this species has undergone severe habitat destruction in the region and land conservation actions are urgent.

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Moss salamanders (genus Nototriton) are represented in northern Central America by nine putative species: N. barbouri, N. brodiei, N. lignicola, N. limnospectator, N. mime, N. picucha, N. saslaya, N. stuarti, and N. tomamorum. I estimate the phylogenetic relationships for these species based on data from three mitochondrial gene fragments (16S, cytochrome b, and COI), and compare morphological variation among putative taxa. As evidenced here and in previous studies, the taxon N. barbouri is paraphyletic with respect to populations from the Cordillera Nombre de Dios in northern Honduras. I restrict this taxon to populations from the Sierra de Sulaco in central Yoro, Honduras, and describe two new species from the Cordillera Nombre de Dios.

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A new yellow salamander belonging to the genus Bolitoglossa, subgenus Eladinea, is described from a premontane rainforest in the vicinity of Moravia de Chirripó, on the northeastern slopes of the Cordillera de Talamanca in Costa Rica at an elevation of ca. 1300 m. This new taxon is distinguished from its congeners by its chromatic and morphological characteristics, and by differentiation in DNA sequences of the mitochondrial 16S rRNA and cytochrome b genes.

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Species of the genus Chiropterotriton are distributed through much of northern and eastern Mexico. The genus has presented taxonomic difficulties, with a number of species waiting to be described. We describe two new species, Chiropterotriton cieloensis sp. nov. and Chiropterotriton infernalis sp. nov., from the Mexican state of Tamaulipas based on both molecular and morphological data. We present a phylogenetic hypothesis for the group, with emphasis on the taxa from northern Mexico, based on mitochondrial DNA, and discuss the other species of northern Mexico, especially the wider-ranging C. multidentatus, to which the new species were formerly assigned.

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Osteological variation is recorded among and within four of the most distinctive species of the Mexican salamander genus Chiropterotriton. Analysis of the data is consistent with the monophyletic status of the genus and documents previously unrecorded intraspecific and interspecific variation. Most of the recorded variation involves qualitative and quantitative proportional differences, but four fixed differences constitute autapomorphic states that affirm and diagnose some species (C. dimidiatus, C. magnipes). Osteological variation in 15 characters is analyzed with respect to predictions generated from four hypotheses: 1) phylogeny, 2) adaptation to specific habitats (the four species include cave-dwelling, terrestrial, and arboreal forms), 3) size-free shape, and 4) size. High levels of intraspecific variation suggest that the characters studied are not subject to rigid functional constraints in salamanders, regardless of size. The pattern predicted by the hypothesis based on size differences seen among these four Chiropterotriton species matches most closely the observed pattern of relative skull robustness. Since size change and heterochrony are often associated in plethodontid evolution, it is likely that changes in developmental timing play a role in the morphological transitions among these morphologically diverse taxa. Webbed feet, miniaturization, body shape, and an unusual tarsal arrangement are morphologies exhibited in species of Chiropterotrition that are shown to be homoplastic with other clades of tropical plethodontids. Although extensive homoplasy in salamanders might be seen as a roadblock to unraveling phylogenetic hypotheses, the homologous developmental systems that appear to underlie such homoplasy may reveal common and consistent evolutionary processes at work.

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We describe a new species of the plethodontid salamander genus Cryptotriton from Honduras after comparing morphological, molecular, and osteological data from the holotype to that of the other nominal forms of the genus. The new species differs from all of the known species of Cryptotriton in at least one character from all three datasets. We also suggest placing C. wakei in the synonymy of C. nasalis after examining the morphological and osteological characters of the single known specimen of C. wakei.

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The highlands of northeastern Honduras remain under-characterized in terms of biological diversity, as exemplified by the regularity of new amphibian and reptile taxa discoveries. Following the recent description of a new species of Nototriton from the Sierra de Agalta in northeastern Honduras, we report the discovery of a second new species of Nototriton from the nearby Parque Nacional Montaña de Botaderos. This new taxon, Nototriton mime sp. nov., is distinguished from other Nototriton by its distinctive pale brown dorsal coloration in adult males, relatively large nares, a relatively broad head, mitochondrial sequence divergence, and phylogenetic relationships, and is geographically isolated from other populations of Nototriton.

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For nearly 40 years Bolitoglossa paraensis has been synonymized with Bolitoglossa altamazonica. This fact has been mainly related to taxonomic ambiguities arising from the morphological similarities between these species and the scarcity of material deposited in collections. However, during the past 30 years new material of Bolitoglossa has been collected in many places throughout the Brazilian Amazonia, including the type locality of B. paraensis, Santa Isabel do Pará. In this article we designate the neotype of B. paraensis based on new material from the type locality, correct misinterpretations about this name. We determined how many species of the genus Bolitoglossa occur in Brazilian Amazonia, described three new species, B. caldwellae sp. nov., B. madeira sp. nov., and B. tapajonica sp. nov., provide a key for identifying Brazilian salamanders. Were analyzed two hundred and seventy eight specimens of Bolitoglossa from the Brazilian states of Acre, Amapá, Amazonas, Pará, and Rondonia; morphological data ofB. altamazonica from Colombia were used for comparison purposes. We confirm the presence of B. altamazonica in extreme western Brazil, and expand the number of species occurring in Brazilian Amazonia to five.

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We describe the new salamander species Bolitoglossa jugivagans from the Atlantic slopes of the Fortuna depression in western Panama on the basis of morphological and molecular data. Based on mtDNA data, the new species seems to be closely related to B. aureogularis and B. robinsoni, with which it forms a subclade within the subgenus Eladinea.

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In this article, a new species of salamander of the genus Bolitoglossa (Eladinea) from the cloud forest near La Mucuy in Sierra Nevada de Mérida, Venezuelan Andes, is described. Bolitoglossa mucuyensis sp. nov. differs from all Venezuelan salamanders, except B. orestes, by a larger SVL/TL ratio, and from La Culata salamander B. orestes by a reduced webbing extension of the front and hind limbs. Additionally, B. mucuyensis sp. nov. and B. orestes diverge 3.12% in terms of the nucleotide sequence of the 16S rRNA gene, as previously reported, and in 8.1% for the cytb gene as shown in this study.

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The salamander fauna of Colombia is very poorly known, probably because most research efforts have been devoted to anurans during the last two decades. Here, we describe two new species of the genus Bolitoglossa (Eladinea) from the eastern flank of the Eastern Colombian Andes (Cordillera Oriental), near the border with Venezuela. Bolitoglossa tamaense sp. nov. is distributed between 2000 to 2700 m.a.s.l. and Bolitoglossa leandrae sp. nov. is distributed in the low-lands at about 600 m. The new species are diagnosed by a combination of molecular (16S rRNA sequences), coloration, body size, and morphometric (number of maxillary and vomerine teeth and differences in foot webbing) characters. Both species face threats such as chytridiomycosis infections and habitat fragmentation that have already affected other sala-manders in the country. Thus, intensive field and museum work is needed to better document and perhaps protect the local salamander diversity.

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Male and female plethodontid salamanders have specialized cloacal glands associated with the reproductive activity. The reproductive cycle in Bolitoglossa nicefori is characterized by males that are potentially reproductive throughout the year, and females that are reproductive only for a few months. To determine whether morphological and histochemical variation occur in cloacal structures related to reproductive activity, the cloacal region of male and female specimens of B. nicefori was studied in different stages of their annual reproductive cycle using light microscopy and compared with features reported in other plethodontid salamanders. The main anatomy and histology of the male and female cloacal regions of B. nicefori are similar to those of other salamanders; however, in comparison to other Bolitoglossa previously studied, B. nicefori has a relatively larger cloacal tube and a tubular rather than acinar spermatheca. As a common trait, the spermatheca has a common tube that diverges into two tubules, before branching into spermathecal tubules, horizontally arranged on frontal planes. The secretions of the spermathecal glands differed between reproductive and nonreproductive adult females. This secretory product consists of prevailing neutral carbohydrates that were related to the increase in ovarian follicular size during the breeding season. Sperm was found only in the spermatheca of reproductive periovulatory females, suggesting that the reproductive cycle involves a no long-term storage of sperm. Although males can produce sperm throughout the year, spermatophores, namely specialized structures involved in sperm transport, were found in their cloaca only during the breeding season. In these males, some of the cloaca-associated glands were seen to undergo change their secretory activity and their secretory products were related to spermatophore formation.

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Webbed foot morphology is a highly homoplastic character in species of Bolitoglossa and has been assumed to be pedomorphic. This study examines the morphology and posthatching ontogeny of the autopodial skeleton of Bolitoglossa nicefori and compares the descriptive and morphometric results with other species of the genus. We show that the autopodial morphology of B. nicefori coincides with the generalized pattern of the genus; webbed foot morphology is produced by pedomorphosis that affect the phalange length of the digits, resulting in a synchronized growth of digits (length and ossification rates) and the fleshy web. Although the webbed foot morphology of B. nicefori might be explained by the pervasive pedomorphic developmental trend observed in the genus, the large degree of variation encountered in the morphology of the distal phalanges indicates that the pedomorphic processes acting in this species are neither a simple truncation of the autopodial developmental program during early posthatching development nor a global process acting over the whole body plan. Instead, this morphological pattern is probably a result of the modular nature of limb development.

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The cranial morphology of the direct-developing salamander Bolitoglossa nicefori and its post-hatching development are described and compared with that of other urodeles. Four stages of cranial development are defined on the basis of conspicuous events that occur during post-hatching ontogeny. The adult skull morphology of B. nicefori is similar to that of other plethodontids; however, some regions show interspecific variation. The post-hatching ontogeny of the skull and the stage of ossification observed in the hatchlings of B. nicefori show two important ontogenetic features: (1) a mosaic of early larval, metamorphic and post-metamorphic skull features in hatchlings, and (2) absence of characteristic larval elements in skull and hyoid apparatus. The distinctive stage of ossification in the hatchlings of B. nicefori could be caused by heterochronic changes in the ossification sequence, compared to the ontogeny of metamorphic salamanders. The possible heterochronic changes and the absence of larval traits are perhaps due to ontogenetic repatterning, yet without an obvious impact on the adult skull morphology (absence of morphological novelties). This might indicate a compartmentalized development. Further studies should be performed in order to establish the possible occurrence of recapitulatory patterns or ontogenetic repatterning in the skull morphogenesis of B. nicefori during its embryonic development.

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The skulls of six species of plethodontid salamanders of the genus Bolitoglossa from Costa Rica and Panama, Bolitoglossa colonnea, B. dofleini, B. lignicolor, B. marmorea, B. schizodactyla and B. striatula are comparatively analysed. All species are terrestrial or slightly arboreal and show no life-mode-dependent skull characteristics. Heads cleared by transparent preparation and stained in toto were used for examination of the skull structure and paraffin sections of the gonads were prepared to confirm sexual maturity of each individual. Focussing on the size of the premaxillary pars dentalis, the degree of fusion of the processus dorsales praemaxillares and the presence or absence of the paired prefrontals we state that B. dofleini and B. striatula possess more ancestral characteristics, B. marmorea is situated in an intermediate position and B. colonnea, B. lignicolor and B. schizodactyla show more advanced characteristics.

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We describe the structure of the skulls of the Costa Rican plethodontid salamanders Bolitoglossa subpalmata, Oedipina uniformis and Nototriton abscondens, and the characteristic sequences of development and ossification of the bony elements resulting from direct development using mainly cleared and stained specimens. Significant differences between the species studied are observed. N. abscondens possesses the broadest premaxillary pars dentalis and O. uniformis the narrowest one. The premaxillary dorsal processes are fused over their rostral third only in B. subpalmata; over half their extention in N. abscondens and almost completely in O. uniformis. A prefrontal is always present in N. abscondens; it is hidden underneath the nasal or missing in B. subpalmata, and it is always absent in O. uniformis. The skull bones, with the exception of the orbitosphenoid, develop and ossify sequentially from caudal to rostral in these directly developing species. A more massive pars dentalis of a generally narrower premaxillary are found as typical characters in males.

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The shape of the teeth and their sex-dependent dimorphic expression in three species of Costa Rican plethodontids (Bolitoglossa subpalmata, Oedipina uniformis and Nototriton abscondens) were studied using light microscopy and scanning electron microscopy. The teeth of the vomerine tooth patches are about one third larger than the teeth of the jaws in B. subpalmata and O. uniformis, whereas all teeth of N. abscondens are of about uniform size. The occurrence of bicuspid tooth germs in the fetus proves that primary teeth are bicuspid in these directly developing plethodontids. Females possess only bicuspid teeth consisting of a pedicel and a crown, as is considered characteristic for urodeles after metamorphosis. Adult males possess conical monocuspid teeth on the premaxillary. These teeth--which are similar to the typical late larval tooth of salamanders presenting a larval stage--are about twice as big as the neighbouring bicuspid maxillary teeth. N. abscondens males possess some monocuspid teeth and teeth of aberrant shapes on the premaxillary and the maxillaries. A tendency to build more monocuspid teeth in the premaxillary region than in the maxillary region can be observed in this species. We suppose that different degrees of sensitivity to androgens in each section of the dental lamina of the upper jaw cause the secondary occurrence of conical monocuspid teeth predominantly on the premaxillary section.

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The pattern of development of teeth and dental laminae of three Costa Rican plethodontids (Amphibia, Urodela, Plethodontidae) was investigated using transparent preparations, light microscopy and scanning electron microscopy. The teeth of the jaws are monostichously positioned, those of the posterior vomeral parts are polystichously arranged. The anterior vomeral parts carry monostichously positioned teeth at the caudal margin; yet, the adult Bolitoglossa subpalmata possesses two lines. As a sex dimorphism adult males display long monocuspid premaxillary teeth which protrude to the outside of the mouth cavity. All species studied possess paired dental laminae in the lower jaw. Nototriton abscondens possesses an unpaired dental lamina in the upper jaw, which is constricted between the unpaired premaxillary and the maxillaries. In contrast, the dental laminae in the upper jaw of B. subpalmata and Oedipina uniformis are segmented into a premaxillary and two maxillary laminae. All species possess a pair of anterior vomeral and a pair of posterior vomeral dental laminae in the adults, whereas the vomeral dental laminae of the subadults are unsegmented. The pattern of dentition is compared with that of Gyrinophilus and Eurycea.

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