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Among direct-developing rain frogs of the genus Craugastor is a clade of 19 described species (bocourti series) that occur in Mexico and northern Central America. Many of these 19 species have been described based on subtle morphological differences and have never been examined using molecular data. Here, we used a multilocus dataset (one mitochondrial (mtDNA) and four nuclear (nDNA) gene fragments, totalling 3,048 concatenated base pairs) to investigate species limits and phylogenetic relationships among 60 northern rain frogs referable to 12 species, with a focus on species from Guatemala. We inferred phylogenies using maximum likelihood and Bayesian analyses on separate mtDNA and nDNA datasets. Concatenated and coalescent species-tree analyses support the monophyly of multiple species, with interspecific relationships mostly unresolved. These mtDNA and nDNA trees were often incongruent with morphology-based taxonomy. For example, two genetically shallow clades contained individuals referable to at least five described species, whereas a single described species contained deep divergences indicative of multiple cryptic species. These findings indicate that morphology-based taxonomy has both overestimated and underestimated actual species diversity (depending on the species), an interpretation supported by two molecular species-delimitation procedures. Based on these findings, we synonymise C. glaucus (Lynch, 1967) and C. stuarti (Lynch, 1967) with C. xucanebi (Stuart, 1941). We also synonymise C. nefrens (Smith, 2005) and C. cyanochthebius McCranie & Smith, 2006 with C. campbelli (Smith, 2005). The molecular data also support multiple undescribed species, notably within C. decoratus (Taylor, 1942). Overall, we show how morphology-based species delimitation can both underestimate and overestimate species richness in morphologically conservative groups. [ABSTRACT FROM AUTHOR]

We review morphology of Sunda Shelf Gonocephalus with an emphasis on Sumatran and Javan species. At least 15 species and subspecies inhabit Peninsular Malaysia, Sumatra, Java, Borneo, and adjacent smaller continental islands. Following analysis of external morphology, we provide a dichotomous key to Sunda Shelf Gonocephalus and resolve two taxonomic problems with this group of lizards. Three populations of Gonocephalus doriae on Borneo, Peninsular Malaysia, and Sumatra are recognized as subspecies, because they lack concordance of multiple morphological differences and have low genetic divergence in a 556 base-pair fragment of the 16S rRNA gene. Described as new herein, G. doriae brevis from Aceh and North Sumatra differs from G. d. abbotti and G. d. doriae in usually having more scales around midbody and a relatively shorter tail with fewer dark bands. Though previously reported as lost, a syntype of G. d. doriae (MSNG 29152) is designated as lectotype, illustrated, and described. Also described as new, G. inauris from high elevations of the Bukit Barisan Range of Bengkulu, Sumatra, is a species of the G. megalepis Group differing from all congeners in having 7/6 (vs. 8–19) loreals separating the last canthal and supralabials, 8/8 (11–27) infraorbitals, and 58 (73–153) scales around midbody. In this new species, distinctly enlarged suboculars broadly contact its supralabials, whereas 1–4 lorilabials separate the suboculars and supralabials in congeners. High genetic divergence in the new species mirrors its high level of morphological divergence. [ABSTRACT FROM AUTHOR]

Experimental research has demonstrated that a stress-is-enhancing mindset can be induced and can improve outcomes by presenting information on the enhancing nature of stress. However, experimental evidence, media portrayals, and personal experience about the debilitating nature of stress may challenge this mindset. Thus, the traditional approach of focusing on the more "desired" mindset without arming participants against encounters with the less desired mindsets may not be sustainable in the face of conflicting information. How might this limitation be resolved? Here, we present three randomized-controlled interventions that test the efficacy of a "metacognitive approach." In this approach, participants are givenmore balanced information about the nature of stress along with metacognitive information on the power of their mindsets aimed at empowering them to choose a more adaptive mindset even in the face of conflicting information. In Experiment 1, employees of a large finance company randomized to the metacognitive mindset intervention reported greater increases in stress-is-enhancing mindsets and greater improvements in self-reported measures of physical health symptoms and interpersonalskill work performance 4weeks later compared to awaitlist control. Experiment 2, adapted to be distributed electronically via multimedia modules, replicates the effects on stress mindset and symptoms. Experiment 3 compares the metacognitive stress mindset intervention with a more traditional stress mindset manipulation. The metacognitive approach led to greater initial increases in a stress-is-enhancing mindset relative to the traditional intervention, and these increases were sustained after exposure to contradictory information. Taken together, these results provide support for a metacognitive approach to mindset change. [ABSTRACT FROM AUTHOR]

Coralsnakes of the genus Micrurus are a diverse group of venomous snakes ranging from the southern United States to southern South America. Much uncertainty remains over the genus diversity, and understanding Micrurus systematics is of medical importance. In particular, the widespread Micrurus nigrocinctus spans from Mexico throughout Central America and into Colombia, with a number of described subspecies. This study provides new insights into the phylogenetic relationships within M. nigrocinctus by examining sequence data from a broad sampling of specimens from Mexico, Guatemala, Honduras, Nicaragua, Costa Rica, and Panama. The recovered phylogenetic relationships suggest that M. nigrocinctus is a species complex originating in the Pliocene and composed of at least three distinct species-level lineages. In addition, recovery of highly divergent clades supports the elevation of some currently recognized subspecies to the full species rank while others may require synonymization. [ABSTRACT FROM AUTHOR]

A new species of Dipsas Laurenti, 1768, from Central Panama is described based on molecular analyses, hemipenial morphology, and external characters. This is the sixth species of Dipsas to be described for the country; the snake has been suspected to exist since 1977 and has not been thoroughly studied until now. Additionally, morphological comparations including scale counts are done with other species within the genus, and the current geographic distribution of Dipsas temporalis (Werner, 1909), the sister species, is updated. Finally, a key to the species of Dipsas currently known from Middle America is presented. [ABSTRACT FROM AUTHOR]

The Craugastor mexicanus series (Anura: Craugastoridae) includes six species of direct-developing frogs that occur in Mexico and Guatemala. Notably, two of these species have small adult body sizes (<18 mm snout to vent length) and several have intraspecific polymorphism in color pattern. Using a geographic sampling focused on eastern Mexico (the location of most type localities), we conducted a molecular phylogenetic analysis of two mitochondrial (12S, 16S) and two nuclear (RAG1, TYR) gene fragments. This analysis revealed two widespread species, C. mexicanus and C. pygmaeus, along with evidence of multiple undescribed taxa from the states of Oaxaca, Mexico, Guerrero, and Jalisco. Interestingly, the widespread species have stratified geographic distributions with the larger bodied clade restricted to high elevations and the smaller bodied clade to low elevations. We also identify regions of Guerrero and Oaxaca where multiple species co-occur. To reevaluate the quality of characters that have been previously used to diagnose species, we tested for heterochrony and sexual dimorphism using microcomputed tomography and linear measurements. We found evidence for paedomorphosis as the mechanism of miniaturization in small-bodied taxa. Linear measurements confirmed that tympanum and body size are sexually dimorphic traits in both small- and large-bodied species. We used this enhanced understanding of morphological variation in the group to describe six new species. Despite this progress, we suspect that additional species await discovery, particularly in western Mexico and east of the Isthmus of Tehuantepec where our sampling efforts were limited. [ABSTRACT FROM AUTHOR]

Rivers are known to act as biogeographic barriers in several strictly terrestrial taxa, while possibly serving as conduits of dispersal for freshwater-tolerant or -dependent species. However, the influence of river systems on genetic diversity depends on taxa-specific life history traits as well as other geographic factors. In amphibians, several studies have demonstrated that river systems have only minor influence on their divergence. Here, we assess the role of the paleodrainage systems of the Sunda region (with a focus on the island of Sumatra) in shaping the evolutionary history of two genera of frogs (Sumaterana and Wijayarana) whose tadpoles are highly dependent on cascading stream habitats. Our phylogenetic results show no clear association between the genetic diversification patterns of both anurans genera and the existence of paleodrainage systems. Time-calibrated phylogenies and biogeographical models suggest that these frogs colonized Sumatra and diversified on the island before the occurrence of the Pleistocene drainage systems. Both genera demonstrate phylogenetic structuring along a north–south geographic axis, the temporal dynamics of which coincide with the geological chronology of proto Sumatran and -Javan volcanic islands. Our results also highlight the chronic underestimation of Sumatran biodiversity and call for more intense sampling efforts on the island. [ABSTRACT FROM AUTHOR]

While species boundaries between conspicuously divergent populations of the medically important snake genus Sinomicrurus are well established, instances of erratic chromatic and meristic variation continue to confound taxonomists, since the mid‐1800s. This predicament can be attributed to an inadequate molecular phylogenetic framework and the lack of a comprehensive taxonomic representation of geographic variants. Here, we revisit lineage delineation in this genus, drawing cohesive evidence from a plurality of data and analysis types, including a promising, yet taxonomically under‐utilized, supervised machine learning algorithm (random forest). Overall, this study incorporates data generated by molecular analyses as well as morphometrics and comparative anatomy based on 236 specimens from 28 different natural history collections examined by us, and an additional 161 records from 47 other sources. Our results indicate several very divergent evolutionary lineages concealed as subspecies. Thus, to better reflect this phylogenetic diversity, we raise S. macclellandi iwasakii from the southern Ryukyus and S. m. swinhoei from Taiwan to full species, and resurrect S. annularis. We highlight the need to distinguish at species level the current subspecies of S. japonicus, namely as, S. japonicus and S. boettgeri, and provide diagnostic characters to that end. On the other hand, given unpersuasive support of lineage independence, we sink Taiwanese S. hatori into S. sauteri and S. nigriventer into S. macclellandi. We also meticulously redescribe S. peinani from mainland China and Vietnam based on a substantial number of additional specimens, while synonymizing the recently described S. houi under S. kelloggi. We conclude with a discussion on the role of regional biogeography as a primary driver of cladogenesis in the genus. [ABSTRACT FROM AUTHOR]

Despite a considerable amount of research, the systematics of the ranid genus Huia have remained unresolved, mostly owing to insufficient sampling and morphological similarities. As currently circumscribed, Huia consists of five species, but multiple studies have consistently demonstrated that it is not a monophyletic genus. However, no study has approached the problem with adequate data and provided a systematically sound solution, leaving the genus to languish in a classification that is phylogenetically incoherent. We generated the most comprehensive sampling of Huia to date, based on extensive fieldwork in Java and Sumatra. Using an integrative taxonomy framework, we analysed four mitochondrial and two nuclear markers and, in conjunction with tadpole morphology, investigated the phylogenetics of Huia and its congeners. Corroborating previous studies, Huia is recovered as a paraphyletic group. Huia cavitympanum emerges as the sister taxon to Meristogenys. The remaining members of Huia form a monophyletic group, sister to the H. cavitympanum + Meristogenys clade. Our extensive geographical sampling in Sumatra and Java reveals multiple highly divergent lineages that potentially represent undescribed species. Using our expanded molecular and morphological dataset, we resolve the paraphyly of Huia by restricting the genus to its type species and propose a new genus to accommodate the strongly supported clade of Sumatran and Javan populations previously belonging to Huia. [ABSTRACT FROM AUTHOR]

The genus Oxybelis currently is composed of four taxa despite numerous studies suggesting and describing multiple taxa within the O. aeneus complex. Here, we utilize a multilocus molecular dataset (i.e., cyt b, ND4, 12S, 16S, cmos, PRLR, 3663 bp) to conduct phylogenetic analyses to assess the evolutionary history of Oxybelis. Our molecular analyses find three major lineages of Oxybelis (i.e., O. aeneus complex, O. brevirostris, O. fulgidus complex) with a sister relationship between O. brevirostris and the O. aeneus complex to the exclusion of the O. fulgidus complex. More specifically, O. aeneus appears to harbor at least five taxa currently unrecognized while O. fulgidus was found to be paraphyletic with respect to O. wilsoni, suggesting cryptic diversity and novel taxa in that clade as well. Additionally, we use morphological data in concert with our molecular analyses and the literature to support removing Oxybelis microphthalmus Barbour and Amaral, 1926; Oxybelis potosiensis Taylor, 1941; and Dryophis vittatus Girard, 1854 from the synonymy of O. aeneus. Finally, we describe two new species from Central America and northern South America. [ABSTRACT FROM AUTHOR]

Lizards of the genus Dendragama are endemic to the highland cloud forests of Sumatra's Barisan Mountain Range in western Indonesia, and recent studies have uncovered widespread diversity within the genus. Here, a suite of morphological characters and mitochondrial DNA are used to compare three geographically isolated populations of D. boulengeri from (1) Mount Kerinci in Jambi province, (2) Mount Marapi of west Sumatra, and (3) the Karo Highlands of north Sumatra. Additional phylogeographic analyses with two recently described sister species, D. australis and D. dioidema were conducted. Five genetically distinct clades of Dendragama, all distributed allopatrically of one another were identified and some are suspected to inhabit small distributions. Morphological and genetic data confirm the Karo Highlands population D. schneideri (previously Acanthosaura schneideri Ahl, 1926) should be revalidated from the synonymy of D. boulengeri. Dendragama schneideri is endemic to montane forests of the Karo Highlands surrounding Lake Toba in Sumatra Utara province. Pairwise genetic distances of 6-11% separate D. schneideri from congeners. Two distinct clades of D. boulengeri from Mount Kerinci and Mount Marapi were identified, which are 5.0% genetically distant from one another. Using morphological characters, we provide the first key for distinguishing between species of Dendragama. Based on biogeographic patterns and levels of genetic variation it is suspected that at least 18 other isolated cloud forest locations may hold new species or divergent populations of Dendragama but lack survey work. Collectively, these comparisons among populations of montane lizards further elucidate the complex biogeographic history of Sumatra's montane forest species and the first phylogeny of the genus Dendragama. [ABSTRACT FROM AUTHOR]

We review morphology and systematics of Phoxophrys using new specimens of previously rare species. In addition to external characters, we relied heavily on skull morphology visualized using computed tomography data of all currently recognized species in this genus. Phylogenetic analysis of ND4, 12S, and 16S mDNA sequences reveal that Ph. tuberculata is sister to a clade containing Dendragama, Lophocalotes, and insular Pseudocalotes. Phoxophrys tuberculata is only distantly related to Bornean congeners. Phylogenetic analysis of 29 morphological characters scored for all the species of Phoxophrys and a diverse set of 22 outgroup taxa found four well-supported lineages: Ph. tuberculata, a clade of all Bornean congeners, Ph. nigrilabris, and a clade of the four large Bornean species. To resolve paraphyly of Phoxophrys, we revalidate Pelturagonia Mocquard for all Bornean species of this genus. As redefined, Phoxophrys contains a single species: Ph. tuberculata of Sumatra. We describe a new species of Pelturagonia from the Meratus Range of southeastern Kalimantan. The new species is the sister species of Pe. spiniceps. Like that species, it differs from congeners in having large, dorsally projecting scales between the dorsolateral caudal crests and a postorbital process of the frontal bone reaching the postciliary ornament. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Sumatran and Javan bent-toed geckos are most closely related to species from the Thai-Malay Peninsula. • Cyrtodactylus most likely dispersed to Sumatra three times during the late Oligocene and early Miocene. • Cyrtodactylus invaded west Java from the Sumatra once in the early Miocene. • Data support lowland connections over highland land bridges as dispersal pathways. Abstract Complex geological processes often drive biotic diversification on islands. The islands of Sumatra and Java have experienced dramatic historical changes, including isolation by marine incursions followed by periodic connectivity with the rest of Sundaland across highland connections. To determine how this geological history influenced island invasions, we investigated the colonization history and diversification of bent-toed geckos (genus Cyrtodactylus) on Sumatra and west Java. We used mitochondrial and nuclear sequence data to explore species boundaries, estimate phylogenetic relationships and divergence times, and to reconstruct ancestral range evolution. We found that Sumatran and Javan Cyrtodactylus were closely related to species from the Thai-Malay Peninsula, rather than from Borneo, and that Cyrtodactylus most likely dispersed to Sumatra three times during the late Oligocene and early Miocene. Similarly, Cyrtodactylus invaded west Java from Sumatra once in the early Miocene. Our results suggest that despite isolation by marine incursions during much of the Miocene, Cyrtodactylus dispersed to and from Sumatra and west Java likely via land bridges, and that in situ diversification occurred several times on Sumatra. [ABSTRACT FROM AUTHOR]

Delimiting species is a crucial goal of integrative biology, and yet can be misled by homoplasy and high levels of morphological variation. The snake tribe Sonorini contains three genera that have long confounded taxonomists: Chilomeniscus, Chionactis and Sonora. Dynamic colour evolution in this group, including rampant geographic variation in colour and colour polymorphism, has led to a chaotic taxonomy. We used mitochondrial and high-throughput nuclear data (ddRADseq) and complete taxonomic sampling of each genus to reconstruct phylogenetic relationships and systematically revise the genus. Our research revealed that Sonora is paraphyletic with regards to Chilomeniscus and Chionactis and that at least one species (S. semiannulata) is paraphyletic with respect to at least one other recognized species. Additionally, we found substantial undescribed genetic diversity within multiple species which is incongruent with morphological variation in coloration. Accordingly, we proposed synonymizing Chionactis and Chilomeniscus with Sonora, which has taxonomic priority over both genera. As we found genetic evidence that supported some of the historically delimited diversity within multiple taxa, we revised species-level taxonomy accordingly. This new taxonomy recognizes a revised genus of Sonora that contains 15 species of diminutive and often brightly coloured snakes that are distributed from central Mexico to north-western USA. http://www.zoobank.org/urn:lsid:zoobank.org:pub:45A553D8-6435-4E0A-84ED-DF31E2CCD872 [ABSTRACT FROM AUTHOR]

The efficacy of academic-mind-set interventions has been demonstrated by small-scale, proof-of-concept interventions, generally delivered in person in one school at a time. Whether this approach could be a practical way to raise school achievement on a large scale remains unknown. We therefore delivered brief growth-mind-set and sense-of-purpose interventions through online modules to 1,594 students in 13 geographically diverse high schools. Both interventions were intended to help students persist when they experienced academic difficulty; thus, both were predicted to be most beneficial for poorly performing students. This was the case. Among students at risk of dropping out of high school (one third of the sample), each intervention raised students’ semester grade point averages in core academic courses and increased the rate at which students performed satisfactorily in core courses by 6.4 percentage points. We discuss implications for the pipeline from theory to practice and for education reform. [ABSTRACT FROM PUBLISHER]

Abstract: A new member of short chain α-neurotoxic protein family from venom of the Mexican coral snake, Micrurus laticollaris, was characterized. This protein, named MlatA1, possesses 61 amino acids with 8 conserved cysteine residues, sharing 30–91% sequence identity with other fully sequenced Micrurus toxins. MlatA1 (LD50i.v. = 0.064 mg/kg) antagonizes with both fetal and adult nicotinic acetylcholine receptor (nAChR) as well as α-7 neuronal nAChR in a dose-dependent way. Specific rabbit anti-Mlat serum (titer higher than 18,000) does not show any protective ability against this toxin, nevertheless it was able to recognize protein bands in six out of twelve Micrurus venoms showing the existence of two distinct antigenic groups for α-neurotoxins in North American coral snakes species. The MlatA1 gene was cloned and used to produce recombinant toxin (rMlatA1) that was recognized by rabbit anti-native toxin but was depleted of toxic activity. [Copyright &y& Elsevier]

• New Molecular phylogeny of Sumatra's cloud forest Draconinae lizards. • Sumatra's montane Draconinae lizards have deep divergence and allopatric distributions. • Draconinae lizard diversity arose from in situ diversification. • Distributions and divergence estimates may elucidate history of Pleistocene forests. Biogeographical evidence, both, for and against the "regional endemism paradigm" hypothesis has been uncovered across the Greater Sunda Region (Sundaland) of Southeast Asia. Additionally, there are competing hypotheses regarding how Pleistocene forests may have impacted biological patterns and processes in Sumatra. Using montane agamid lizards from Sumatra, we derived and analyzed a phylogenetic dataset, genetic divergence estimates, and contemporary distributional patterns among species. We tested whether (1) Sumatra's highland Draconinae diversification fits the regional endemism paradigm hypothesis and (2) Draconinae phylogeography provides biological evidence for Pleistocene forest extent at various points in history. Our results suggest in situ diversification was the main driver behind montane Draconinae lizard diversification in Sumatra, rejecting the "regional endemism paradigm". Contemporary distribution of endemic species and their genetic relationships may potentially provide biological evidence for determining more precise elevational lower limits of montane forests during the Pleistocene epoch. Our data suggests montane forests did not retreat more than 700–750 m during glacial maxima because lower retreating forests would have become interconnected, allowing for widespread dispersal, exchange of gene flow and sympatric distributions contemporarily. To the contrary, our divergence estimates show that cloud forest dragons have been isolated for millions of years, suggesting there may have been a continuous disconnect between some areas, predating the Pleistocene. There may also be other ecological and evolutionary factors that impacted Draconinae distributions, such as competition, making this an excellent system for testing questions regarding montane biogeography. Additionally, we provide the first phylogeny for a wide range of Sundaland agamid species and identify some biogeographic pressures that may have triggered montane Draconinae diversification in Sumatra. [ABSTRACT FROM AUTHOR]

• A taxonomy based solely on coloration has hindered phylogenetic resolution of the M. diastema species complex. • Strong conflict exists between mtDNA and nuclear-based estimates of evolutionary relationships and distinctness. • Genome-wide SNPS resolve contentious relationships within the group. • We present a revised taxonomy for the M. diastema clade. New world coralsnakes of the genus Micrurus are a diverse radiation of highly venomous and brightly colored snakes that range from North Carolina to Argentina. Species in this group have played central roles in developing and testing hypotheses about the evolution of mimicry and aposematism. Despite their diversity and prominence as model systems, surprisingly little is known about species boundaries and phylogenetic relationships within Micrurus , which has substantially hindered meaningful analyses of their evolutionary history. Here we use mitochondrial genes together with thousands of nuclear genomic loci obtained via ddRADseq to study the phylogenetic relationships and population genomics of a subclade of the genus Micrurus : The M. diastema species complex. Our results indicate that prior species and species-group inferences based on morphology and color pattern have grossly misguided taxonomy, and that the M. diastema complex is not monophyletic. Based on our analyses of molecular data, we infer the phylogenetic relationships among species and populations, and provide a revised taxonomy for the group. Two non-sister species-complexes with similar color patterns are recognized, the M. distans and the M. diastema complexes, the first being basal to the monadal Micrurus and the second encompassing most North American monadal taxa. We examined all 13 species, and their respective subspecies, for a total of 24 recognized taxa in the M. diastema species complex. Our analyses suggest a reduction to 10 species, with no subspecific designations warranted, to be a more likely estimate of species diversity, namely, M. apiatus , M. browni , M. diastema , M. distans , M. ephippifer , M. fulvius , M. michoacanensis , M. oliveri , M. tener , and one undescribed species. [ABSTRACT FROM AUTHOR]

• Evolutionary models support Pleistocene divergence between lineages. • Evident mito-nuclear discordance was observed. • Andes mountains indirectly acted as a porous barrier to dispersal. • We provide support to the taxonomic status of R. horribilis. The high levels of Neotropical biodiversity are commonly associated with the intense Neogene-Quaternary geological events and climate dynamics. Here, we investigate the evolutionary history of two species of Neotropical closely related amphibians (R. horribilis and R. marina). We combine published data with new mitochondrial DNA sequences and multiple nuclear markers, including 12 microsatellites. The phylogenetic analyses showed support for grouping the samples in two main clades; R. horribilis (Central America and Mexico) and R. marina (South America east of the Andes). However, the phylogenetic inferences also show an evident mito-nuclear discordance. We use Approximate Bayesian Computation (ABC) to test the role of different events in the diversification between the two groups recovered. We found that both species were affected primarily by a recent Pleistocene divergence, which was similar to the divergence estimate revealed by the Isolation-with-Migration model, under persistent bidirectional gene flow through time. We provide the first evidence that R. horribilis is differentiated from the South American R. marina at the nuclear level supporting the taxonomic status of R. horribilis , which has been controversial for more than a century. [ABSTRACT FROM AUTHOR]

The rough teiid or water cork lizard (Echinosaura horrida) is a small reptile from Colombia and Ecuador placed in a genus that contains eight species and well-known phylogenetic relationships. Here we provide a detailed description and illustrations, bone by bone, of its skull, while we discussed its intraspecific variation by comparing high-resolution computed tomography data from two specimens and the variation within the genus by including previously published data from Echinosaura fischerorum. This allowed to propose putative diagnostic character states for Echinosaura horrida and synapomorphies for Echinosaura. In addition, our discussion includes broader comparisons of new character transformations of the jugal, vomer, orbitosphenoid, and hyoid. These characters are important for diagnosing clades at different levels of the Gymnophthalmoidea phylogeny., (© 2024 American Association for Anatomy.)

Evidence of fluctuations in transport have long been predicted in 3 He. They are expected to contribute only within 100μK of T c and play a vital role in the theoretical modeling of ordering; they encode details about the Fermi liquid parameters, pairing symmetry, and scattering phase shifts. It is expected that they will be of crucial importance for transport probes of the topologically nontrivial features of superfluid 3 He under strong confinement. Here we characterize the temperature and pressure dependence of the fluctuation signature, by monitoring the quality factor of a quartz tuning fork oscillator. We have observed a fluctuation-driven reduction in the viscosity of bulk 3 He, finding data collapse consistent with the predicted theoretical behavior., (© 2023. Springer Nature Limited.)

A promising way to mitigate inequality is by addressing students' worries about belonging. But where and with whom is this social-belonging intervention effective? Here we report a team-science randomized controlled experiment with 26,911 students at 22 diverse institutions. Results showed that the social-belonging intervention, administered online before college (in under 30 minutes), increased the rate at which students completed the first year as full-time students, especially among students in groups that had historically progressed at lower rates. The college context also mattered: The intervention was effective only when students' groups were afforded opportunities to belong. This study develops methods for understanding how student identities and contexts interact with interventions. It also shows that a low-cost, scalable intervention generalizes its effects to 749 4-year institutions in the United States.

A new species of Dipsas Laurenti, 1768, from Central Panama is described based on molecular analyses, hemipenial morphology, and external characters. This is the sixth species of Dipsas to be described for the country; the snake has been suspected to exist since 1977 and has not been thoroughly studied until now. Additionally, morphological comparations including scale counts are done with other species within the genus, and the current geographic distribution of Dipsastemporalis (Werner, 1909), the sister species, is updated. Finally, a key to the species of Dipsas currently known from Middle America is presented., (Julie M. Ray, Paola Sánchez-Martínez, Abel Batista, Daniel G. Mulcahy, Coleman M. Sheehy III, Eric N. Smith, R. Alexander Pyron, Alejandro Arteaga.)

We describe Sceloporus huichol sp. nov., a new species of spiny lizard of the genus Sceloporus, that is found in the mountainous regions of Jalisco and Nayarit in western Mexico. The new species belongs to the torquatus species group and has previously been confused with Sceloporus melanogaster, from which it differs by its smaller size, head color and nuchal collar. Additionally, Sceloporus huichol sp. nov. is different from the rest of its congeners by relevant genetic and morphologicall data. Despite having a complete nuchal collar, characteristic of Sceloporus torquatus, S. huichol sp. nov. is more closely related phylogenetically to S. melanogaster. Recognition of this new species brings the number of species in the torquatus group to nine.

We evaluated the taxonomic status of the genus Megophrys in Sumatra using molecular and morphological data. Mitochondrial phylogenetic inference and morphological data revealed two undescribed species, one in southern SumatraM. selatanensis sp. nov. and one in northern SumatraM. acehensis sp. nov. We also detected a potential cryptic species within M. parallela, but refrain from describing this lineage here due to insufficient data. Genetic variation within Sumatran Megophrys is highly structured and will require additional geographic sampling to understand the interplay between geography and genetics in Sumatran Megophrys.

A tiny new species of narrow-mouthed frog of the genus Microhyla is described from the island of Belitung and southeastern Sumatra, Indonesia. The most distinctive feature of the new frog is its diminutive adult size, snout-vent length ranging only from 12.3 to 15.8 mm in adult males. Phylogenetic analyses based a fragment of the mitochondrial 16S rRNA gene, along with detailed morphological and acoustic comparison differentiate the new taxon from all known congeners. The new species, formally described as Microhyla sriwijaya sp. nov., is a member of the M. achatina species group and the sister taxon to M. orientalis. It is diagnosable from other congeners by a combination of characters: (1) smaller male snout-vent size 16 mm; (2) snout obtusely rounded in dorsal view; (3) absence of mid-dorsal line and skin fold; (4) first finger reduced (finger I length less than half of finger II length); (5) dorsum with a prominent dark median mark extending posteriorly, narrow anteriorly near the level of the shoulder and expanding dorsolaterally up to the vent; margins of the dorsal marking concave with broad reddish-brown or orange colouration on either side; (6) foot webbing rudimentary, reaching just up to the first subarticular tubercle on all toes; (7) dorsal skin with prominent tubercles, especially in life; (8) tibiotarsal articulation of adpressed limb reaching beyond the snout tip; and (9) males produce a single type of call with pulsatile temporal structure, calls of relatively short duration ranging between 31.862.8 s, with two to three pulses delivered at a rate ranging between 32.236.0 pulses per second, and the mean overall dominant frequency of 4.3 kHz. The uncorrected pairwise genetic distances between Microhyla sriwijaya sp. nov. and all other known congeners are > 3.8% for the studied 16S gene fragment. The new species was discovered from wayside rural areas with oil palm plantations at four localities in the small island of Belitung (type locality), and from coffee plantation and secondary forest at Lampung in southeastern Sumatra. It is not known from any protected area and appears to be threatened due to tin mining activity, intensive logging, oil palm, and other commonly practiced agriculture activities.

We describe a new species of gymnophthalmid lizard, Oreosaurus bisbali sp. nov., from the Turimiquire Massif in northeastern Venezuela. It is one of three reptile species known to be endemic to the region and the fifth species of Oreosaurus from Venezuela. It can be distinguished from all congeners by a combination of rectangular dorsal scales at midbody, having two scales separating femoral pores medially, and lacking a nasoloreal suture. The new species is likely to be restricted in distribution to the highlands of the Turimiquire Massif, which have been significantly degraded by agriculture.

A new species of natricine snake of the genus Rhabdophis is described from Northeast India. Morphologically the new species is similar to Rhabdophis himalayanus but it can be distinguished from it by lacking a nuchal groove and nuchal glands, being relatively smaller, and having a distinct neck, ventral, and subcaudal coloration. In overall coloration it resembles R. chrysargos, from which it is distinguished by several aspects of its morphology and genetic differences. The discovery of Rhabdophis bindi sp. nov. reveals that forested regions in the northeastern part of India needs further biological exploration.

Cancer chiefly occurs in vertebrates. Rare in amphibians, and perhaps common in reptiles, various neoplasms and malignant cancers have been reported with erratic frequency by museums, paleontologists, veterinarians, and pet hobbyists. Unsurprisingly, most herpetofaunal diversity has never been systematically surveyed for the presence of neoplasms owing to the extreme rarity or obscurity of many species. Museum collections can fill these gaps in knowledge, especially when researchers use non-destructive techniques. In this study, we used X-ray computed tomography (CT) to discover and characterize a possible osteosarcoma of the spine in a rare South American coralsnake, Micrurus ancoralis. Two spinal vertebrae were completely fused and adjacent vertebrae showed evidence of corruption. The fused vertebrae contained a hollow inner network thought to be vascular tissue. We also review previous reports of neoplasms in the Elapidae and all bony neoplasms in non-avian reptiles. The rarely reported technique of X-ray CT for tumor discovery could greatly improve our understanding of the species diversity and perhaps underlying causes of neoplasia., (© 2020 American Association for Anatomy.)

The bent-toed geckos of the genus Cyrtodactylus are the most speciose land vertebrates of Southeast Asia (about 300 species so far) and new species continue to be recognized at a rapid rate. Within the last decade three new species were described from Java, Indonesia, C. semiadii, C. petani, and C. klakahensis. The latter two are very similar, except for differences in the precloacal depression in adult males. These two species have relatively close type localities, separated from each other by only about 50 km, and with similar habitat type and elevation. Our study aimed to evaluate the taxonomic status of C. klakahensis and C. petani using both morphological and genetic evidence. These two species are genetically similar, with a genetic divergence of only 1.5 to 1.6%. This divergence is well below the level of typically characterizes sister species of Cyrtodactylus (approximately 4% in the mitochondrial ND2 gene), and is more in line with population variation due to geographic distance. Further examination of specimens, from both type localities, showed no diagnostic morphological characters between the two species. Thus, we conclude that C. klakahensis and C. petani are conspecific, and following article 23 of the ICZN, C. klakahensis is herein considered a junior synonym of C. petani.