In altered postdisturbance habitats, sympatric organisms that have different life history strategies may manifest different epigenetic marks in response to changing landscapes. Herein, we explore how DNA methylation patterns change in response to wildfire in two sympatric lizard species with different life histories: Florida Scrub Lizard (Sceloporus woodi) and Six-Lined Racerunner (Aspidocelis sexlineata). Both lizards prefer habitats that have experienced recent wildfire, yet they differ in distribution, body size, life span, reproductive output, vagility, home range size, diet, behavior, and morphology and have different patterns of genetic diversity and differentiation. We used epiRADseq to screen DNA methylation levels in Florida Scrub Lizards (n = 35) and Six-Lined Racerunners (n = 30) from rosemary (Ceratiola ericoides) scrub sites with different time since fire at Archbold Biological Station and Reserve, Florida, USA. We detected seven genomic locations in Florida Scrub Lizards with increased methylation in the site with most recent time since fire compared with individuals from the site with longest time since fire. We failed to detect differential methylation among locations in the Six-Lined Racerunner genome. We also found DNA methylation was positively correlated with time since fire for Florida Scrub Lizards and negatively correlated with time since fire for Six-Lined Racerunners. Our results indicate DNA methylation may play an important role in mediating the response of disturbance-dependent organisms to changing conditions, but the response of methylation to wildfire likely differs among species.

Recent research has documented widespread biofluorescence across amphibians. Among caudates in particular, representative species from 8 of the 10 families fluoresce under blue light excitation. Although fluorescence has been reported on the ventral surface of the tail in Eastern Red-backed Salamanders, Plethodon cinereus, nothing is known about the source or function of the fluorescence. This fully terrestrial salamander species has a broad geographic range, has complex mating behavior involving chemosensory and visual behaviors, defends territories from conspecific and heterospecific intruders, and is a model organism for studying many aspects of sociobiology. Our goal was to learn more about the source of fluorescence in P. cinereus and to explore demographic patterns of fluorescence. Additionally, we wanted to establish whether there is seasonal and geographic variation in fluorescence in this widespread salamander species. Through our examination of histological literature and close examination of photos of the ventral surface of tails under both white and UV light, we concluded that S1 glands, which comprise the postcloacal gland (PCG) in P. cinereus, are the source of fluorescence on the ventral portion of the tail. We found this trait to be highly sexually dimorphic, with males having significantly more fluorescent S1 glands both across seasons and localities compared to females. Additionally, we found that fluorescence only occurs in adult salamanders. Further, because the ventral surface of the tail is exposed during courtship and during territorial disputes, we hypothesize that male fluorescence of the PCG may function in the context of both mate choice and territoriality.

Size and location of territories have important fitness consequences for breeding males in many species, including lizards. Australian Water Dragons (Intellagama lesueurii) are an interesting study system in which to examine socio-ecological aspects of territory size and male behavior because, despite their large body size, these lizards form dense aggregations within urban riparian habitats. In one such population, we found that males defended territories smaller than have been reported for most other large lizards. Surprisingly, smaller males defended larger territories, but larger territories did not increase access to females. Instead, territory size was negatively correlated with conspecific density, including females, which in turn was highest near a creek that provided abundant prey and refuges. That is, territories were smaller in sites offering more resources for reproduction, feeding, and predator evasion. The relative proportion of displays males gave during contests with rivals did not vary within the reproductive season. However, male travel and the context of stereotypical head displays showed a surprising pattern of seasonal variation. As the season progressed, males increased the proportion of displays to females, but decreased the proportion of undirected territorial advertisement displays. Because Water Dragons are long-lived and philopatric, increased display during interactions with postbreeding females may enhance mating opportunities in future reproductive seasons.

The ecology of many arboreal ectotherms is poorly understood because of access constraints to the forest canopy. For example, despite their common name, Gray Treefrogs (Hyla versicolor) are understudied in arboreal habitats. Advancements in camera trap technology and tree-climbing techniques have created new opportunities to study arboreal species. Using arboreal camera trapping and time-lapse photography, we implemented the first study of H. versicolor behavior in the canopy. We examined seasonal and diel patterns of activity, microhabitat use, and effects of relative humidity and temperature on H. versicolor activity in eastern white pine (Pinus strobus) canopies. We installed camera traps at three research sites in northern Wisconsin, USA, spanning a 57-km north–south transect, and maintained them for multiple years. We detected H. versicolor events, of all sex–age classes, at two of our research sites. Use of time-lapse photography significantly improved our ability to detect H. versicolor in the canopy. Hyla versicolor individuals were active in the canopy every year of the study (2015–18), but predominantly during the summer, and peak diel activity occurred predominantly during the night (between 2100 and 2300 h). Hyla versicolor activity significantly increased as relative humidity and temperature increased. Hyla versicolor individuals were significantly more active in the upper canopy compared with other canopy locations and selected for the top side of branches. Our results highlight that H. versicolor frequent arboreal habitats of P. strobus canopies. Although further research is needed, our work lays a foundation of H. versicolor ecology within the canopy. This research also demonstrates the feasibility of using arboreal camera traps with time-lapse settings to study ectotherms in forest canopies.

Turtles are one of the most imperiled vertebrate groups in the world. With habitat destruction unabated in many places, urban and suburban greenspaces may serve as refugia for turtles, at least those species able to tolerate heavily altered landscapes. In south-central Louisiana, we have conducted a turtle capture–mark–recapture effort in two ponds in an urban greenspace for 13 yr to understand species composition, survival, and individual growth rates. We had 574 total captures of 251 individuals of five species from 2009–2021, with Trachemys scripta elegans (Red-Eared Sliders) and Sternotherus odoratus (Eastern Musk Turtles) being the most common. Apparent annual survival for T. scripta (0.79) was similar to estimates reported in other studies in altered habitats, whereas apparent annual survival for S. odoratus (0.89) was slightly or much higher than other published studies. Growth rates of T. scripta were comparable to other studies and showed both sexes have similar rates of growth until maturity, which is earlier and at a smaller size in males. The two ponds showed marked differences in captures by size, with significantly more juvenile T. scripta captured in the pond with more vegetation, depth, and a softer bottom. Most T. scripta (78.5%) that were recaptured came from the same pond from which they were originally captured. The basic demographic data gained in this study can serve as a starting point for broader questions on urbanization effects and as a comparison to more natural populations.

Rough Bent-Toed Gecko, Cyrtopodion scabrum (Heyden, 1827), is an invasive species in Algeria and northwestern Africa. We provide detailed information on the morphometry and diet of C. scabrum from an urban area in Debila (northeastern Oued Souf), Algeria. We found a significant correlation between morphological characters (body length, snout–vent length, and tail length) in individuals within each sex, but no differences in morphometry between females and males. Analysis of stomach contents of 30 specimens (15 adult males, 15 adult females) resulted in identification of 198 prey items belonging to 2 classes, 8 orders, 20 families, and 29 genera. The diet of C. scabrum was mainly composed of arthropods and was highly diverse (Shannon index = 4.3). Insects were the main food item, accounting for 96.5% of prey consumed, followed by arachnids (3.5%). The most important prey categories were Hymenoptera (40.4%), Diptera (19.7%), Lepidoptera (12.6%), and Coleoptera (12.1%).

Le Gecko Cyrtopodion scabrum (Heyden, 1827) est l'une des espèces envahissantes en Algérie et en Afrique du Nord-Ouest. Dans cette étude, nous fournissons des données détaillées sur la morphométrie et le régime alimentaire de ce Gecko dans la zone urbaine de Debila (nord-est de l'Oued Souf), en Algérie. Nous avons trouvé une corrélation significative entre les caractères morphologiques (la longueur total, la longueur total, et la longueur de la queue) chez les individus du même sexe mais pas entre les sexes (femmes et mâles). L'analyse du contenu stomacal de 30 spécimens (15 mâles adultes, 15 femelles adultes) a abouti à l'identification de 198 proies appartenant à 2 classes, 8 ordres, 20 familles et 29 genres différents. Le régime alimentaire de nos spécimens est composé principalement d'arthropodes; il est très diversifié (indice de Shannon = 4.3). Les insectes étaient le principal aliment, représentant 96.5% des proies consommées suivis des arachnides (3.5%). Les catégories de proies les plus importantes sont les hyménoptères (40.4%), les diptères (19.7%), les lépidoptères (12.6%) et les coléoptères (12.1%).

Yucatán Box Turtles (Terrapene yucatana) are the only fully tropical lineage of box turtles (Terrapene spp.). We studied the ecology, movements, behavior, and habitat associations of T. yucatana in northern Yucatán, México, over 218 field days from 2014–2019. We estimated the size of two subpopulations to comprise 36.6 and 3.0 turtles, with corresponding densities of 2.29 and 0.39 turtles/ha, respectively. We obtained 2,808 radio locations from radiotelemetry of 20 adults. We estimated an annual survivorship rate over a 5-yr period exceeding 0.989. For both sexes combined, the average annual 95% minimum convex polygon (MCP) home range size was 0.684 ha, and the average distance between consecutive annual home range centroids was 22.5 m. In 2 of 5 yr, males exhibited significantly larger 95% MCP home ranges than females. We observed feeding, courtship, and fighting in the wild between June and December. Females moved more than males in July, when gravid turtles were also observed. We found that T. yucatana was positively associated with Mimosa sp. and Bromelia spp. The use of aquatic habitats was infrequent (0.17%). Our findings support the conclusion that T. yucatana, an allopatric and fully tropical lineage, is an interior forest and thornscrub species that occurs at low densities. In such undisturbed contexts, T. yucatana may exhibit high survivorship rates, small home range size, and home range fidelity that underscore the importance of large-scale forest conservation efforts in concert with the targeted protection of documented Yucatán Box Turtle populations.

La tortuga de caja de Yucatán (Terrapene yucatana) es el único linaje completamente tropical de tortugas de caja (Terrapene spp.). Realizamos un estudio de la ecología, movimientos, comportamiento y asociaciones de hábitat de T. yucatana en el norte de Yucatán, México, durante 218 días de campo entre 2014 y 2019. Estimamos el tamaño de dos poblaciones comprendidas en 36,6 y 3,0 tortugas, respectivamente, con densidades correspondientes a 2,29 y 0,39 tortugas / ha. Obtuvimos 2,808 radiolocalizaciones de 20 tortugas adultas. Estimamos una tasa de supervivencia anual superior a 0,989 basado en el marcado y recaptura de 37 individuos. Para ambos sexos, el tamaño medio anual del área de distribución (95% del MCP) fue de 0,684 ha, y la distancia entre los centroides del área de distribución anual consecutivos fue de 22,5 m. Los machos exhibieron rangos de distribución significativamente mayores que las hembras en 2 de los 5 años. Observamos alimentación, cortejo y peleas en su estado natural entre junio y diciembre. Las hembras se movieron más que los machos en julio, cuando también se observaron tortugas grávidas. Encontramos que T. yucatana se asoció positivamente con Mimosa sp. y Bromelia spp. El uso de hábitats acuáticos fue infrecuente (0,17%). Terrapene yucatana, un linaje alopátrico y completamente tropical de las tortugas de caja de América del Norte, es una especie de bosque interior y matorrales espinosos que ocurre en densidades bajas. En ambientes no perturbados, T. yucatana puede exhibir altas tasas de supervivencia, un ámbito hogareño pequeño y una notable fidelidad a su ámbito doméstico, lo que acentúa la importancia de los esfuerzos de conservación de bosques a gran escala junto con la protección específica de poblaciones documentadas de tortugas de caja.

We lay out mass-bulk theory (MBT)—relationships for gape-limited predators among relative prey mass (RPM), relative prey bulk (RPB), prey shape, prey taxon, and feeding frequency. Elongate reptiles with narrow mouths eat tiny items; chunks of prey; or, as with many snakes, “large” animals ingested intact. RPM and RPB define item size, with implications for costs and benefits of feeding. Prey are heavy, bulky, both, or neither, only relative to consumers. Type I items are not heavy or bulky; they require minimal handling and gape, but many must be eaten. High RPM, high RPB, or both characterize types II, elongate (e.g., eels); III, fusiform to ovoid (e.g., mice); and IV, nonuniform in cross-sectional dimensions (e.g., some fishes), density (e.g., birds), and/or deformability (e.g., crustaceans). High handling costs and payoffs characterize types II and III; III and IV require wider gape, but IV comes with lower RPM, costs, and payoffs. RPM and RPB have implications for biology and conservation, such that heavy, bulky, or heavy and bulky—but not large—usefully describe prey size. We explore MBT with 1) natural history vignettes and graphical integration of RPM, RPB, prey shapes, and feeding frequency; 2) nonvenomous colubrids that vary in gape and diet; (3) front-fanged colubroids that consume lizards, centipedes, or earthworms; and (4) bird-eating snakes. Further testing of MBT is hampered by logistical and cultural challenges. Our explorations are bookended by reflections of a herpetologist enjoying his eighth decade, emphasizing how an early-career publication stemmed from youthful experiences and led to this review.

HWG reflexiona sobre como una publicación en los inicios de una carrera académica se originó de experiencias juveniles y derivó en la vida de un herpetólogo disfrutando su octava década. Relacionado con ello, definimos la teoría masa-volumen (TMV)—la relación para predadores limitados por el tamaño de su boca entre la masa relativa de su presa (MRP), el volúmen relativo de la presa (VRP), la forma de la presa, el taxon de la presa, y la frecuencia de alimentación. Los reptiles de cuerpos alargados y bocas estrechas obtienen su alimento de porciones o presas pequeñas, de partes pequeñas de presas grandes, o de presas “grandes” ingeridas completas, como lo hacen muchas serpientes. MRP y VRP definen el tamaño de la porción, y tienen implicaciones en los costos y beneficios de la alimentación. Las presas pueden ser pesadas, voluminosas, ambas o ninguna, en relación con su depredador. Las presas de tipo I, no son pesadas ni voluminosas; son fáciles de manipular y no requieren bocas grandes, pero deben consumirse muchas. MRP alta, VRP alta, o ambas, definien a las presas tipo II, alargadas, como las anguilas; tipo III, esferoides a ovoides, como los ratones; y tipo IV, no uniformes en sección transversal, como algunos peces, o no uniformes en densidad, como las aves. Costos de manipulación y beneficios nutricionales altos caracterizan a los tipos II y III; los tipos III y IV requieren bocas más grandes, pero el tipo IV implica una MRP baja, y costos y beneficios nutricionales más bajos. MRP y VRP tienen implicaciones biológicas y de conservación, de manera que es útil describir la presa como pesada, voluminosa, o pesada y voluminosa—pero no grande. Aquí exploramos la TMV con 1) viñetas de historia natural e ingración gráfica de MRP, VRP, tipos de formas de presas, y frecuencia de alimentación; 2) colúbridos no venenosos, que varían en tamaño de boca y en dieta; 3) colubroideos con colmillos frontales que consumen lagartijas, ciempiés, o gusanos de tierra; y 4) serpientes que consumen aves. Pruebas adicionales de la Teoría Masa-Volúmen son obstaculizadas por retos logísticos y culturales.

Reeves' Turtles (also known as Chinese Three-Keeled Pond Turtles, Mauremys reevesii) exhibit temperature-dependent sex determination (TSD). Recent studies reported genome sequencing and described normal embryonic and gonadal developmental patterns in M. reevesii, making them a promising model for studying TSD. Nevertheless, development of other reproductive organs, such as the Müllerian duct, has not been described in this species. The Müllerian duct is a tubular structure that primarily forms in mesonephros during embryogenesis in both sexes. While the Müllerian duct further develops into the reproductive tract in females, it typically regresses in males. In this study, we investigated the development and regression of the Müllerian duct in M. reevesii during the latter half of embryogenesis under female- (FPT; 318C) and male-producing temperatures (MPT; 268C). Histological analysis revealed that the Müllerian duct showed the first sign of regression at the end of the temperature-sensitive period under MPT and significantly regressed at the prehatching stage (stage 24). Development and regression of the Müllerian duct in M. reevesii followed general trajectories reported in mouse and chicken studies. Timing of regression was consistent with reports in another TSD turtle, Pond Sliders (Trachemys scripta). Our study provides a basis for comparative studies of reproductive organs in TSD species and for elucidating mechanisms leading to sexual differentiation.

The number of described species of Pseudopaludicola has increased at unprecedented rates over the past two decades. This increase was mainly driven by the sampling effort in regions historically neglected and the use of evidence from bioacoustic, genetic, and morphological datasets combined. Here, we describe a new species of Pseudopaludicola from a transitional zone between Amazonia and Cerrado in western Tocantins State as revealed through morphological, molecular, and bioacoustic analysis. Pseudopaludicola javae sp. nov. is distinguished from its congeners by its small size; knobbed terminal phalanges; smooth upper eyelids and heel; relatively short hind limbs; smooth, whitish, and subgular inflated vocal sac with few melanophores around the jaw; and advertisement call composed of an irregular series of multipulsed notes with 10–17 nonconcatenated pulses separated by intervals of 3–55 ms, emitted at a rate of 27–51 pulses/sec. The new species occurs in four Tocantins municipalities, all in the Araguaia–Tocantins interfluve. We also provide the first records of Pseudopaludicola jazmynmcdonaldae outside the type locality (Caseara Municipality, Tocantins State), extending its distribution nearly 245 km southward from Caseara. Pseudopaludicola javae sp. nov. is the second species of Pseudopaludicola described recently from western Tocantins.

O número de espécies de Pseudopaludicola descritas cresceu a taxas sem precedentes nas últimas duas décadas. Esse aumento foi impulsionado principalmente pelo esforço de amostragem em regiões historicamente negligenciadas e pelo uso de evidências bioacústicas, genéticas e morfológicas. Nós descrevemos uma nova espécie de Pseudopaludicola de uma zona de transição entre a Amazônia e o Cerrado no oeste do estado do Tocantins revelada através de análises morfológicas, moleculares e bioacústicas. Pseudopaludicola javae sp. nov. é diagnosticada de seus congêneres por seu pequeno tamanho, falanges terminais simples, pálpebras superiores e calcanhar lisos, membros posteriores relativamente curtos, saco vocal subgular, liso e esbranquiçado quando inflado com poucos melanóforos ao redor da mandíbula, e canto de anúncio composto por séries irregulares de notas com 10–17 pulsos não concatenados separados por intervalos de 3–55 ms, emitidos a uma taxa de 27–51 pulsos/s. A nova espécie ocorre em quatro municípios do Tocantins, todos no interflúvio Araguaia-Tocantins. Também fornecemos aqui os primeiros registros de P. jazmynmcdonaldae fora da localidade tipo (município de Caseara, estado do Tocantins), estendendo sua distribuição em cerca de 245 km em linha reta ao sul de Caseara. Pseudopaludicola javae sp. nov. é a segunda espécie de Pseudopaludicola descrita para o oeste do Tocantins nos últimos anos.

Sea Turtles lay eggs at relatively deep depths on beaches. Although nest emergence is known to be costly for hatchlings, little is known about the positive aspects of emergence. In this study, we investigated the effects of emergence on hatchling phenotypes of Loggerhead Sea Turtles (Caretta caretta) in the North Pacific population. We placed the Loggerhead eggs in an incubator (incubator group) and relocated some eggs to a sand tank after the pip was confirmed (emergence group). Immediately after emergence was confirmed in the emergence group, we compared the morphology, terrestrial locomotor performance, and swimming performance of the two groups at the same time. Results showed that hatchlings in the emergence group were smaller than those in the incubator group. Notably, most members of the emergence group were able to completely traverse a 3-m course within 3 min, whereas no members of the incubator group could traverse the course. The emergence group had greater swimming performance than the incubator group. Taken together, these results suggest that emergence may have a positive effect on locomotor performance. Sea turtle nests are occasionally relocated for conservation purposes, and our results suggest that such egg management practices can alter hatchling phenotypes.