Unveiling the Venom Composition of the Colombian Coral Snakes Micrurus helleri, M. medemi, and M. sangilensis.

Little is known of the biochemical composition and functional features of the venoms of poorly known Colombian coral snakes. Here, we provide a preliminary characterization of the venom of two Colombian endemic coral snake species, Micrurus medemi and M. sangilensis, as well as Colombian populations of M. helleri. Electrophoresis and RP-HPLC techniques were used to identify venom components, and assays were conducted to detect enzyme activities, including phospholipase A2, hyaluronidase, and protease activities. The median lethal dose was determined using murine models. Cytotoxic activities in primary cultures from hippocampal neurons and cancer cell lines were evaluated. The venom profiles revealed similarities in electrophoretic separation among proteins under 20 kDa. The differences in chromatographic profiles were significant, mainly between the fractions containing medium-/large-sized and hydrophobic proteins; this was corroborated by a proteomic analysis which showed the expected composition of neurotoxins from the PLA2 (~38%) and 3FTx (~17%) families; however, a considerable quantity of metalloproteinases (~12%) was detected. PLA2 activity and protease activity were higher in M. helleri venom according to qualitative and quantitative assays. M. medemi venom had the highest lethality. All venoms decreased cell viability when tested on tumoral cell cultures, and M. helleri venom had the highest activity in neuronal primary culture. These preliminary studies shed light on the venoms of understudied coral snakes and broaden the range of sources that could be used for subsequent investigations of components with applications to specific diseases. Our findings also have implications for the clinical manifestations of snake envenoming and improvements in its medical management.

A generalized framework for estimating snakebite underreporting using statistical models: A study in Colombia.

BACKGROUND: Snakebite envenoming is a neglected tropical disease affecting deprived populations, and its burden is underestimated in some regions where patients prefer using traditional medicine, case reporting systems are deficient, or health systems are inaccessible to at-risk populations. Thus, the development of strategies to optimize disease management is a major challenge. We propose a framework that can be used to estimate total snakebite incidence at a fine political scale. METHODOLOGY/PRINCIPAL FINDINGS: First, we generated fine-scale snakebite risk maps based on the distribution of venomous snakes in Colombia. We then used a generalized mixed-effect model that estimates total snakebite incidence based on risk maps, poverty, and travel time to the nearest medical center. Finally, we calibrated our model with snakebite data in Colombia from 2010 to 2019 using the Markov-chain-Monte-Carlo algorithm. Our results suggest that 10.19% of total snakebite cases (532.26 yearly envenomings) are not reported and these snakebite victims do not seek medical attention, and that populations in the Orinoco and Amazonian regions are the most at-risk and show the highest percentage of underreporting. We also found that variables such as precipitation of the driest month and mean temperature of the warmest quarter influences the suitability of environments for venomous snakes rather than absolute temperature or rainfall. CONCLUSIONS/SIGNIFICANCE: Our framework permits snakebite underreporting to be estimated using data on snakebite incidence and surveillance, presence locations for the most medically significant venomous snake species, and openly available information on population size, poverty, climate, land cover, roads, and the locations of medical centers. Thus, our algorithm could be used in other countries to estimate total snakebite incidence and improve disease management strategies; however, this framework does not serve as a replacement for a surveillance system, which should be made a priority in countries facing similar public health challenges.

Unwrapping broken tails: Biological and environmental correlates of predation pressure in limbless reptiles.

Studying species interactions in nature often requires elaborated logistics and intense fieldwork. The difficulties in such task might hinder our ability to answer questions on how biotic interactions change with the environment. Fortunately, a workaround to this problem lies within scientific collections. For some animals, the inspection of preserved specimens can reveal the scars of past antagonistic encounters, such as predation attempts. A common defensive behaviour that leaves scars on animals is autotomy, the loss of a body appendage to escape predation. By knowing the collection site of preserved specimens, it is possible to assess the influence of organismal biology and the surrounding environment in the occurrence of autotomy. We gathered data on tail loss for 8189 preserved specimens of 33 snake and 11 amphisbaenian species to investigate biological and environmental correlates of autotomy in reptiles. We applied generalized linear mixed effect models to evaluate whether body size, sex, life-stage, habitat use, activity pattern, biome, tropicality, temperature and precipitation affect the probability of tail loss in limbless reptiles. We observed autotomy in 23.6% of examined specimens, with 18.7% of amphisbaenian and 33.4% of snake specimens showing tail loss. The probability of tail loss did not differ between snakes and amphisbaenians, but it was higher among large-sized specimens, particularly in adults and females. Chance of tail loss was higher for diurnal and arboreal species, and among specimens collected in warmer regions, but it was unaffected by biome, precipitation, and tropicality. Autotomy in limbless reptiles was affected by size-dependent factors that interplay with ontogeny and sexual dimorphism, although size-independent effects of life-stage and sex also shaped behavioural responses to predators. The increase in probability of tail loss with verticality and diurnality suggests a risk-balance mechanism between species habitat use and activity pattern. Although autotomy is more likely in warmer regions, it seems unrelated to seasonal differences in snakes and amphisbaenians activity. Our findings reveal several processes related to predator-prey interactions involving limbless reptiles, demonstrating the importance of scientific collections to unveil ecological mechanisms at different spatio-temporal scales.

ID please: Evaluating the utility of Facebook as a source of data for snake research and conservation.

Social media has the potential to provide large amounts of biological data, especially for notoriously difficult groups of organisms to study in nature such as snakes. Here, we explored the utility of various Facebook communities to provide data for research on Colombian snakes. Specifically, we determined the richness, distribution, rarity, and popularity of snake species and compiled information on natural history observations and human-snake interactions. We also explored the spatial structure of posts using a geographically weighted regression model. Queries relating to species identifications made up 86.1% of Facebook posts. The portion of the snake community "sampled" by snake-related Facebook posts was not representative of the total richness of snake species in Colombia; however, these posts permitted a greater proportion of snake species to be sampled more rapidly compared with traditional snake sampling approaches. Facebook posts provided new distributional records for 9-21% of Colombian snake species. Rainfall, rural population, and internet availability were the strongest predictors of snake-related Facebook posts. Although the use of Facebook for compiling information on snakes is not free of bias, our findings demonstrate that Facebook communities provide a potentially powerful source of data that could aid studies of snake biology.

Hidden in the highs: two new species of the enigmatic toadheaded pitvipers of the genus Bothrocophias

Bothrocophias microphthalmus (Cope, 1875) currently comprises most mid- to highland populations of the genus Bothrocophias in the eastern versant of the Andes. We describe two new species of Bothrocophias from the highlands of the Colombian Andes previously referred to as B. microphthalmus based on morphological and genetic evidence. Our phylogenetic analysis revealed that B. micropthalmus as currently recognized is paraphyletic with respect to B. hyoprora, and the two new taxa are sister lineages. These new toadheaded pitvipers can be morphologically distinguished from their congeners based on the presence of contact between the internasal scales, the number of prefoveal scales, the presence of a lacunolabial scale, the arrangement of supralabial scales, ventral scale counts, the color pattern of the dorsal and ventral surfaces of the body and tail, and hemipenial morphology. We discuss some possible taxonomic scenarios for the lineages found within the B. microphthalmus species complex but refrain from making additional taxonomic changes given our reduced sampling of the southern lineages.

Extended diagnosis of the type species of Pseudogonatodes Ruthven 1915 (Gekkota: Sphaerodactylidae).

Pseudogonatodes furvus is an endemic gecko from the region of the Sierra Nevada de Santa Marta, an isolated massif located in the continental Caribbean region of Colombia. Pseudogonatodes furvus is the type species of the genus, and its morphology and natural history remain poorly known. This lizard was described based on two specimens. After its description, the species has only been mentioned in a handful of taxonomic studies of Pseudogonatodes, in which a few morphological characters of P. furvus have been mentioned. One other paper reported two new localities, without providing new information on the external morphology, especially the lepidosis of the newly obtained specimens. Here we review the external morphology of P. furvus, based on examination of the holotype and six additional specimens. We provide an extended diagnosis and definition, description of holotype, variation, comparisons with other Pseudogonatodes, geographic distribution (adding a fourth locality to the known distribution for the species), and conservation status. Additionally, we describe osteological features for the diagnosis of the genus.

Distribution, habitat suitability, conservation state and natural history of endangered salamander Bolitoglossa pandi.

BACKGROUND: Pandi's mushroom-tongue salamander (Bolitoglossa pandi) is one of the threatened amphibians in South America, as well as a flagship species for the Colombian conservation agenda. This species is endemic to the Andean cloud forests of the western slope of the Cordillera Oriental of Colombia, occurring only in the department of Cundinamarca within a narrow elevational range. At night, B. pandi can be seen perching on the upper side of leaves at heights ranging from ground level to 2.5 m. During the day, it can be found under leaf litter or cover objects. Few studies have provided relevant information that can help the Colombian government to formulate lines of action for the conservation of this species; consequently, its threat assessments so far have been based on very limited information. METHODS: We conducted surveys for salamanders in four municipalities of Cundinamarca, Colombia, using two approaches: visual encounter surveys (Guaduas and Villeta) and the basic sampling protocol for single-species occupancy modeling (Supatá and Venecia). Multivariate analyses were employed to explore the correlation between habitat structure and natural history traits, abundance, and detection/non-detection of B. pandi. We evaluated the B. pandi activity pattern through kernel density curves for each sampling occasion and explored the variability of salamander abundance during their activity period by performing a nested ANOVA. RESULTS: We report the discovery of two new populations of B. pandi, which represent the most northwestern records known. A significant correlation between body length, body mass, and habitat structure was observed. Multivariate analyses indicated that leaf litter depth, mean temperature, percent vegetation cover, and altitude were the habitat variables that together explained 60.3% of the B. pandi abundance variability, as well as the main determinants of its optimal habitat. Bolitoglossa pandi exhibits an activity pattern characterized by two main activity peaks, in which niche time-partitioning was observed. Across the surveyed area, we found a healthy, stable, highly dense population of B. pandi (>1,300 individuals), with seasonal variability between development stages. DISCUSSION: Given the high habitat specificity of B. pandi, the species is highly vulnerable to local changes. Thus, we recommend that B. pandi be retained as Endangered (EN) on the IUCN Red List, based on the IUCN Criterion B, given its restricted extent of occurrence (ca. 2,500 km2) and the ongoing threats from agriculture, cattle ranching, logging, and urban development, which continue to reduce its suitable habitat.

A case of envenomation by the false fer-de-lance snake Leptodeira annulata (Linnaeus, 1758) in the department of La Guajira, Colombia. / Un caso de envenenamiento por mordedura de una serpiente falsa cabeza de lanza, Leptodeira annulata (Linnaeus, 1758), en el departamento de La Guajira, Colombia

Envenomations by colubrid snakes in Colombia are poorly known, consequently, the clinical relevance of these species in snakebite accidents has been historically underestimated. Herein, we report the first case of envenomation by opisthoglyphous snakes in Colombia occurred under fieldwork conditions at the municipality of Distracción, in the department of La Guajira. A female biologist was bitten on the index finger knuckle of her right hand when she tried to handle a false fer-de-lance snake (Leptodeira annulata). Ten minutes after the snakebite, the patient started to have symptoms of mild local envenomation such as edema, itching, and pain in the wound. After 40 minutes, the edema reached its maximum extension covering the dorsal surface of the right hand and causing complete loss of mobility. The clinical treatment focused on pain and swelling control. No laboratory tests were performed. The patient showed good progress with the total regression of the edema 120 hours after the snake-bite accident and complete recovery of the movement of the limb in one week. Venomous bites of "non-venomous snakes" (opisthoglyphous colubrid snakes) must be considered as a significant public health problem because patients lose their work capability during hours or even days and they are forced to seek medical assistance to treat the envenomation manifestations.

Los envenenamientos por colúbridos en Colombia son poco conocidos, por lo que la relevancia clínica de estas especies de serpientes en los accidentes ofídicos ha sido históricamente subestimada. Se presenta el primer caso de envenenamiento por una serpiente opistoglifa en Colombia, ocurrido bajo condiciones de trabajo de campo en el municipio de Distracción, departamento de La Guajira. Una bióloga fue mordida en el nudillo del dedo índice de la mano derecha cuando trató de manipular una falsa cabeza de lanza o falsa mapanare (Leptodeira annulata). Diez minutos después de la mordedura de la serpiente, la paciente presentó síntomas de envenenamiento local leve, como edema, picazón y dolor en la herida. Después de 40 minutos, el edema alcanzó su extensión máxima, cubriendo la superficie dorsal de la mano derecha y causando la pérdida completa de la movilidad. El tratamiento clínico se centró en el control del dolor y la inflamación. No se hicieron pruebas de laboratorio. La paciente tuvo una buena evolución, con la regresión total del edema 120 horas después del accidente ofídico y la normalización de los movimientos de la extremidad a la semana. Las mordeduras venenosas de serpientes "no venenosas" (serpientes colúbridas opistoglifas) deben considerarse un problema de salud pública importante, ya que los pacientes pierden la capacidad de trabajo durante horas o días y se ven obligados a buscar asistencia médica para contrarrestar las manifestaciones locales de envenenamiento.

A case of envenomation by the false fer-de-lance snake Leptodeira annulata (Linnaeus, 1758) in the department of La Guajira, Colombia / Un caso de envenenamiento por mordedura de una serpiente falsa cabeza de lanza, Leptodeira annulata (Linnaeus, 1758), en el departamento de La Guajira, Colombia

Envenomations by colubrid snakes in Colombia are poorly known, consequently, the clinical relevance of these species in snakebite accidents has been historically underestimated. Herein, we report the first case of envenomation by opisthoglyphous snakes in Colombia occurred under fieldwork conditions at the municipality of Distracción, in the department of La Guajira. A female biologist was bitten on the index finger knuckle of her right hand when she tried to handle a false fer-de-lance snake (Leptodeira annulata). Ten minutes after the snakebite, the patient started to have symptoms of mild local envenomation such as edema, itching, and pain in the wound. After 40 minutes, the edema reached its maximum extension covering the dorsal surface of the right hand and causing complete loss of mobility. The clinical treatment focused on pain and swelling control. No laboratory tests were performed. The patient showed good progress with the total regression of the edema 120 hours after the snake-bite accident and complete recovery of the movement of the limb in one week. Venomous bites of "non-venomous snakes" (opisthoglyphous colubrid snakes) must be considered as a significant public health problem because patients lose their work capability during hours or even days and they are forced to seek medical assistance to treat the envenomation manifestations.

Los envenenamientos por colúbridos en Colombia son poco conocidos, por lo que la relevancia clínica de estas especies de serpientes en los accidentes ofídicos ha sido históricamente subestimada. Se presenta el primer caso de envenenamiento por una serpiente opistoglifa en Colombia, ocurrido bajo condiciones de trabajo de campo en el municipio de Distracción, departamento de La Guajira. Una bióloga fue mordida en el nudillo del dedo índice de la mano derecha cuando trató de manipular una falsa cabeza de lanza o falsa mapanare (Leptodeira annulata). Diez minutos después de la mordedura de la serpiente, la paciente presentó síntomas de envenenamiento local leve, como edema, picazón y dolor en la herida. Después de 40 minutos, el edema alcanzó su extensión máxima, cubriendo la superficie dorsal de la mano derecha y causando la pérdida completa de la movilidad. El tratamiento clínico se centró en el control del dolor y la inflamación. No se hicieron pruebas de laboratorio. La paciente tuvo una buena evolución, con la regresión total del edema 120 horas después del accidente ofídico y la normalización de los movimientos de la extremidad a la semana. Las mordeduras venenosas de serpientes "no venenosas" (serpientes colúbridas opistoglifas) deben considerarse un problema de salud pública importante, ya que los pacientes pierden la capacidad de trabajo durante horas o días y se ven obligados a buscar asistencia médica para contrarrestar las manifestaciones locales de envenenamiento.

Exploring the reproductive ecology of the tropical semifossorial snake Ninia atrata.

Based on histological analyses and field studies, this research describes the reproductive ecology of a population of Ninia atrata snakes inhabiting an oil palm plantation. Furthermore, through a multivariate approach, we explored the main drivers of reproductive output in N. atrata. Results showed that prey abundance and food intake were crucial variables contributing to reproductive output. Multiple linear regression models showed that neonates had high sensitivity ( R 2=55.29%) to extreme changes in climate, which was strongly related to slug and snail abundance variability and microhabitat quality. Reproductive cycles were markedly different between the sexes, being continuous in males and cyclical in females. Despite this variation, reproductive cycles at the population level were seasonal semi-synchronous. Constant recruitment of neonates all year, multiple clutches, high mating frequency, and continuous sperm production characterized the reproductive phenology of N. atrata. In addition, a significant number of previtellogenic females presented oviductal sperm as well as uterine scars, suggesting a high precocity in the species. The main drivers of reproductive output also differed between the sexes. In females, clutch size and secondary follicle variability were highly related to stomach bolus volume, fat body area, and body mass. In males, height of piles of palm leaves and body mass, rather than intrinsic reproductive traits, were the main drivers of sperm production. Nevertheless, in both cases, the relationship between body mass, prey abundance, and food intake suggests that N. atrata follows the income breeding strategy to compensate for reproductive costs and to maximize fitness.

On the second specimen of Atractus alytogrammus (Serpentes: Dipsadidae), with description of its unusual hemipenial morphology.

The semi-fossorial snakes of the genus Atractus Wagler 1828 are widely distributed throughout South America, ranging from Panama to northeastern Argentina at elevations from sea level to 4500 m (Passos et al. 2013a). Atractus currently comprises 150 species that inhabiting several types of tropical habitats, being the most diverse genus of snakes in the world (Passos et al. 2018). Colombia harbours the most species richness of the genus with about 42 currently recognized species, representing about 1/3 of generic diversity (Uetz et al. 2018). Köhler Kieckbusch (2014) recently has named Atractus alytogrammus based on an individual collected by Federico Meden more than fifty years ago near the municipality of San José de Guaviare (2°33'55''N, 72°38'19''W). The second known specimen of A. alytogrammus was found by A.F. Aponte (male, ICN-R-13018) hidden under a pile of palm leaves (3°00'05"N, 72°13'9.9"W; 209 m above sea level) at 7:58 am on February 02 2016 in the oil palm plantations of POLIGROW Colombia Ltda, municipality of Mapiripán, department of Meta, Colombia. This region is located in the Orinoquia-Amazonia ecotone 82 Km (airline) northeast from the type-locality (Fig. 1). I report herein the unknown color in life (Fig. 2), change of shades after preservation (Fig. 3B-D) and hemipenial morphology (Fig. 4), besides amplifying the meristic and morphometric variability of this poorly known species (Table 1).

A new species of Ninia (Serpentes: Dipsadidae) from Chocó-Magdalena biogeographical province, western Colombia.

We describe a new species of the genus Ninia from the Chocó-Magdalena biogeographic province, which was previously reported as a distinct population of N. maculata or as N. atrata from the western slopes of the Cordillera Occidental of Colombia. The new species is similar to N. atrata, N. celata, N. espinali, N. franciscoi, and N. maculata. It shares the following characteristics with the species mentioned above: 19 dorsal scale rows without reductions; dorsal ground color black or dark brown; white or cream occipital nuchal collar. However, it is easily distinguished from all other congeners because it has a non-regular color pattern in the ventral surfaces of the head and body, subcaudal surface homogeneously black or dark brown, two nasal scales, and one lateral projection ornamented with a large basal hook-shaped spine that is larger than any other spine on the hemipenial body. The presence of a lateral projection on the hemipenial body makes the new species the only member of the genus from South America that shares this feature with its Central American congeners. This feature suggests a closer relationship with this linage. Finally, our results indicate that proper and careful revision of the Ninia atrata species complex will help to understand and clarify the taxonomic composition of the genus.