Turtles of the World: Annotated Checklist and Atlas of Taxonomy, Synonymy, Distribution, and Conservation Status (9th Ed.)
Abstract
This is our 9th edition of an annotated checklist and atlas of all recognized taxa of the world’s modern turtle and tortoise fauna, documenting recent changes and controversies through mid-2021, and including all primary synonyms, updated from eight previous checklists. We provide an updated comprehensive listing of taxonomy and nomenclature, including type localities, type specimens, detailed distribution maps, as well as calculated presumed historic indigenous ranges, conservation status, and maximum known sex-based carapace lengths for all taxa. We strive to record the most recent justified taxonomic assignment of taxa in a hierarchical framework, providing detailed annotations, including alternative arrangements for a few taxa. We include current published and provisional IUCN Red List status assessments for all species, as well as current listings on CITES appendices. The diversity of turtles and tortoises in the world that has existed in modern times (since 1500 CE) and currently generally recognized as distinct and included in this checklist, now consists of 357 species. Of these, 58 are polytypic, representing 129 additional recognized subspecies (one unnamed), or 486 total taxa of modern chelonians, increased from 478 taxa in our previous checklist. Of these, 5 species and 5 subspecies (one unnamed), or 10 taxa (2.1%), are extinct. We also include a supplementary checklist of 17 taxa of terrestrial chelonians that went extinct during the Holocene from ca. 10,000 BCE to 1500 CE. As of the current IUCN 2021 Red List, 171 turtle species (62.4% of the 274 species red-listed, 47.9% of all 357 recognized modern species) are officially regarded as globally Threatened (Critically Endangered [CR], Endangered [EN], or Vulnerable [VU]). We record additional provisional Red List assessments by the IUCN Tortoise and Freshwater Turtle Specialist Group, allowing us to evaluate the overall current threat levels for all 357 species of turtles and tortoises. Of these, 183 (51.3%) are Threatened (CR, EN, or VU); if we provisionally adjust for predicted threat rates of Data Deficient (DD) species, then ca. 55.9% of all extant turtles are Threatened. These numbers and percentages of Threatened species have increased since our last checklist, although our reclassification of 12 Threatened Galápagos tortoises as subspecies rather than species has moderated the results; the number and percentage of Threatened species increases to 193 (52.3% of 369) if they are considered full species. Turtles and tortoises are among the most threatened of the major groups of vertebrates.
... However, some authors argue that morphological differences allow it to be recognized as a separate species (Okamoto & Kamezaki, 2014). However, we prefer to follow the more conservative position most specialists adopt, considering this population as a more melanistic one of the same nominal species (Bowen & Karl, 2000;Rhodin et al., 2021). ...
... We follow the suggestions of Fritz et al. (2012), who propose the synonymy of Trachemys emolli with T. grayi, distributed in Costa Rican Pacific lowlands. Two subspecies are recognized: T. grayi emolli (in the Lake Nicaragua basin and adjacent lands in northern Costa Rica) and T. grayi panamensis McCord, Joseph-Ouni, Hagen, & Blanck, 2010 in the South Pacific of Costa Rica (Rhodin et al., 2021). On the other hand, the status of T. venusta is a subject of intense debate. ...
... On the other hand, the status of T. venusta is a subject of intense debate. However, we align with Rhodin et al. (2021) suggestion, recognizing T. venusta uhrigi (McCord, et al., 2010) from the Caribbean lowlands of Costa Rica. In contrast, Fritz et al. (2012) propose that populations of these subspecies be recognized as T. ornata, adding to the intrigue and complexity of the taxonomic landscape. ...
Introduction: The herpetological collection of the Museum of Zoology at the University of Costa Rica (MZUCR) has been key to safeguarding a sample of the diversity of amphibians and reptiles of Costa Rica and maintaining an up-to-date catalog of species present in the country. This unit develops phylogenetic and biogeographic studies on these animals and plays an important role in taxonomic decisions about them. Objectives: In this work, we review and update the list of amphibians and reptiles of Costa Rica, commenting on cases with some taxonomic controversy. In addition, we briefly account for the MZUCR herpetological collection and explore its history. Methods: We update the list of present species based on identifying specimens kept in our collection and reviewing relevant scientific literature. In addition, we compile the information available in internal documents and scientific publications to establish the history of the collection. Results: We recognized 221 species of amphibians and 257 species of reptiles in Costa Rica, representing 17 and 36 families, respectively. More than 99% of amphibian species and 97% of reptiles are represented in our collection , which currently has more than 24 000 properly cataloged specimens. The collection houses 39 holotypes and 190 paratypes of 47 species, demonstrating its key role in taxonomic studies of the local herpetofauna. Although amphibian and reptile sampling cover almost the entire country, the northern lowlands and the Caribbean foothills of the Talamanca Mountain range require more significant collecting efforts. Conclusions: Despite its long and intense history of biological exploration, records of Costa Rica's herpetologi-cal diversity continue to increase. Much of this growth is a result of efforts made at the MZUCR. Since its origin as a modest private collection in the early 1960s, it has grown into one of the most comprehensive collections of amphibians and reptiles inhabiting Costa Rica. It also functions as a research unit that generates substantial biological knowledge about both groups.
... Using historical and genetic evidence, Kehlmaier et al. (2024) reconstructed the provenance of the type specimen of C. intergularis and restricted its type locality to Somerset, Cape York Peninsula (Queensland). Chelodina siebenrocki and C. intergularis are currently regarded as junior synonyms of C. rugosa sensu stricto (TTWG 2021;Kehlmaier et al. 2024). In the early 21 st century, a misidentification of the putative holotype of C. oblonga as representing a northern Australian species (Thomson 2000) caused additional nomenclatural upheavals, resulting in changes of various subgenus and species names (Table 1; see also Georges and Thomson 2010;Kuchling 2010;Cann and Sadlier 2017;TTWG 2017;Kehlmaier et al. 2019;Shea et al. 2020). ...
... The Kimberley taxon was not differentiated from C. burrungandjii from Arnhem Land in an R35 phylogeny, but represented another mitochondrial lineage (Alacs 2008). Chelodina walloyarrina was and is listed as a valid species by the Turtle Taxonomy Working Group (Rhodin et al. 2008;TTWG 2010TTWG , 2011TTWG , 2012TTWG , 2014TTWG , 2017TTWG , 2021, but was synonymized with C. burrungandjii by Georges and Thomson (2010), Thomson et al. (2011), Ellis and Georges (2015), and Petrov et al. (2023), despite morphological and mitochondrial differences. Shea et al. (2020) considered the Kimberley taxon a subspecies of the Arnhem Land taxon using the name combination C. burrungandjii walloyarrina. ...
... Currently, different classifications compete (Table 1), also compromising the identification of published DNA sequences. We provisionally accept the classification outlined in Table 1 as a starting point for the present study, following the most recent checklist of the Turtle Taxonomy Working Group (TTWG 2021). Figure 1 summarizes the distribution ranges of the taxa relevant to the present investigation. ...
Using mitochondrial genomes and nine nuclear loci, we examined genetic variation in snake-necked turtles (Chelodina sensu lato), with a focus on northern Australian taxa. The mitochondrial phylogeny of the genus is confounded by multiple introgression events, rendering the subgenera Chelodina sensu stricto and Chelydera non-monophyletic. However, in the analyses of our nuclear dataset (6071 bp), the recognition of the subgenera is supported. The morphologically most distinct taxa (Chelodina expansa, C. longicollis, C. oblonga, C. parkeri, C. steindachneri) are well differentiated genetically. However, many other species are not or only weakly distinct, calling their validity into question. Our dataset includes sequences from historical museum material and the holotype of C. kuchlingi, a species currently listed as Critically Endangered by the Biodiversity Conservation Act of Western Australia. Resequencing its mitogenome using protocols optimized for formalin-preserved specimens provides evidence that the formerly reported mitochondrial distinction of C. kuchlingi was based on a sequencing artifact. Two historical specimens of C. kuchlingi are genetically indistinguishable from snake-necked turtles living today on the Ord River floodplain. In addition, C. walloyarrina, a geographically close taxon with introgressed mitochondria from another species, is not differentiated on the nuclear genomic level. We conclude that Chelodina walloyarrina (McCord & Joseph-Ouni, 2007) is a junior synonym of Chelodina kuchlingi Cann, 1997 and that the extant snake-necked turtles from the Ord River floodplain are conspecific. This implies that morphological traits used in the past to diagnose the involved taxa are less important than previously thought. The redefined species C. kuchlingi is distributed on the sandstone plateau and associated escarpments as well as on the lowland coastal plains of the Kimberley region of tropical northern Australia. It no longer qualifies as Critically Endangered and has to be downlisted, pending a new status evaluation. Our results underline the importance of a robust taxonomy for conservation decisions. Further research is warranted to examine the validity of the remaining weakly differentiated Chelodina taxa, which could not be resolved in our analyses.
... This spatial dimension, associated with extensive availability of freshwater ecosystems, permits a rich biodiversity, especially of freshwater turtles. Added to the species richness of this group in the Amazon River basin and in other Amazonian rivers, Brazil ranks third in global species richness of turtles, with a high degree of endemism, and this biome is considered a priority region for conservation of the group -Global Turtle Hotspot (Mittermeier et al., 2015;Ribeiro-Junior and Amaral, 2016;Rhodin et al., 2021;Cunha et al., 2022;Guedes et al., 2023). ...
... Kinosternon scorpioides (Linnaeus, 1766), the Scorpion Mud Turtle, is a species of freshwater turtle that is widely distributed in the Neotropical region. It occurs from Panama, along the Caribbean range to Brazil, covering the entire Amazon rainforest, the eastern Cordilleras of Colombia, Ecuador and Peru, also reaching the limit of its occurrence in south-central Bolivia, northern Paraguay and northern Argentina in the Chaco Cordillera (Cáceres-Martínez et al., 2017;Rhodin et al., 2021;Cassano and Alcalde, 2022;Hurtado-Gómez et al., 2024). ...
... In several points, the environment described in this research resembles the other places where K. scorpioides was found, ranging from Panama to Brazil, through countries in South America to northern Argentina (Caceres-Martinez et al., 2017;Rhodin et al., 2021). In Brazil, despite being present in several parts of the Amazon, the species was recorded in significant populations only on the island of Marajó (Pará) and environmental protection area of the Baixada Maranhense (Rodrigues et al., 2017). ...
In this study, we sampled populations of Scorpion Mud Turtles, Kinosternon scorpioides, in rivers and flooded plains of the eastern Brazilian Amazon in order to obtain information on its reproductive biology as well as the geospatial description of its habitat. The research was conducted in the basins of the Pericumã and Aurá Rivers, located in the environmental protection area of the Baixada Maranhense. Seven collections were made over a period of 24 months; 206 animals were captured (101 males and 105 females), with 18 recaptures (8.6%) and a displacement record of 7.41 km. In the Aurá River basin, we recorded six nests of K. scorpioides buried in association with a plant of the genus Andropogon sp. Turtles were observed in a variety of environments in a distribution completely dependent on seasonal changes in its habitat, fluctuating between aquatic and terrestrial microhabitats along with seasonal rains and dry periods and food availability. This study adds data on the ecology and knowledge of the dynamics and habitats of K. scorpioides in relation to conservation strategies of these and other turtles that use these flooded plains as habitat and survive despite many anthropogenic disturbances in the region.
... Infested tortoises are the Greek tortoise, also commonly known as the spur-thighed tortoise Testudo graeca, the Hermann's tortoise Testudo hermanni, the Horsfield's tortoise, also known as Russian tortoise, Afghan tortoise or four-clawed tortoise Testudo horsfieldii, the Kleinmann's tortoise, also called the Egyptian tortoise Testudo kleinmanni, and the marginated tortoise Testudo marginata. Their current natural distributions have been documented by Rhodin et al. (2021). Tortoises of the genus Testudo have long been exported into many countries around the world to be kept as pets. ...
... At a similar geographical latitude, H. aegyptium has also been found on the north-eastern Black Sea coast of Russia, also on T. graeca (Apanaskevich, 2003). In between lies the Crimean peninsula, where an introduced or possibly historically relict population of T. graeca has been mapped (Rhodin et al., 2021). This location in the south of the Crimea is also marked in the map of Feider (1965) and refers to the occurrence of H. aegyptium mentioned by Hoogstraal (1956). ...
... T. graeca, 3.8% T. hermanni, 2.8% T. horsfieldii and 0.8% T. marginata. Since some authors simplify the description of the host animals as tortoises, the species names have been added when this was clearly evident from the geographical distribution of the five Testudo species according to Rhodin et al. (2021). A total of 21 tortoises without species information was specified as T. graeca and three as T. horsfieldii (). ...
The tortoise tick Hyalomma aegyptium (Linnaeus, 1758) is a three-host tick, predominantly infesting land tortoises of the genus Testudo. A database was compiled, resulting in 557 H. aegyptium georeferenced locations in the Palearctic. This dataset covers the entire range of H. aegyptium for the first time. Thus, the natural distribution area of H. aegyptium extends from Morocco in northwestern Africa to Kyrgyzstan in Central Asia between 10° W-73° E and 28-46° N, which is shown in an overview map and four detailed maps covering North Africa, the Balkans, the Near East, and the Middle East. In addition, documented findings on land tortoises that have been exported worldwide as popular pets give an impression of the occurrence of H. aegyptium outside its natural distribution. The host species is known from 424 mapped H. aegyptium locations, which can be ranked as follows: 92.9% Testudo spp., 4.0% mammals (mainly hedgehogs and hares), 1.7% humans, 0.9% lizards and 0.5% birds. If only tortoise hosts are considered, these are 92.6% Testudo graeca, 3.8% Testudo hermanni, 2.8% Testudo horsfieldii and 0.8% Testudo marginata. It is striking that no infestation with H. aegyptium has been detected on Testudo kleinmanni in their natural habitat, but it was detected on imported specimens in Malta and the USA. Although numerous tick-borne pathogens have been detected in H. aegyptium, vector competence, i.e. the experimentally proved transmission of pathogens from the vector to the host, could only be demonstrated for three pathogens. These are the two blood parasites Hemolivia mauritanica and Hepatozoon kisrae as well as Coxiella burnetii, the causative agent of Q fever.
... Continental America is home to up to 13 Trachemys species and 11 additional subspecies (TTWG 2021). Four further species with three additional subspecies occur on the West Indies. ...
... Trachemys is a morphologically diverse ge-nus, with taxa having a variegated ornamental pattern involving colorful ocelli, spots or streaks that are particularly obvious in hatchlings and juveniles. The maximum carapacial length of Trachemys ranges from 21 to 55 cm (straight line), with the largest taxa occurring in Central America (TTWG 2021). Trachemys are known as slider turtles, and their best-known representative is the red-eared slider (T. ...
... scripta elegans), a subspecies of T. scripta, widely distributed in the southcentral USA and adjacent Mexico. It has been introduced to many countries (TTWG 2021) and is listed among the 100 worst invasive species of the world (Lowe et al. 2004). Sliders, short for slider turtles, are omnivorous and occur in a variety of freshwater habitats, with a general preference for quiet waters with soft bodies, rich aquatic vegetation and suitable basking sites (Ernst and Barbour 1989). ...
Trachemys is a speciose genus of freshwater turtles distributed from the Great Lakes in North America across the southeastern USA, Mexico and Central America to the Rio de la Plata in South America, with up to 13 continental American species and 11 additional subspecies. Another four species with three additional subspecies occur on the West Indies. In the present study, we examine all continental Trachemys taxa except for Trachemys hartwegi using mitochondrial and nuclear DNA sequences (3221 and 3396 bp, respectively) representing four mitochondrial genes and five nuclear loci. We also include representatives of all four West Indian species and discuss our results in the light of putative species-diagnostic traits in coloration and pattern. We provide evidence that one Mexican species, T. nebulosa, has captured a deeply divergent foreign mitochondrial genome that renders the mitochondrial phylogeny of Trachemys paraphyletic. Using nuclear markers, Trachemys including T. nebulosa represents a well-supported monophylum. Besides the mitochondrial lineage of T. nebulosa, there are six additional mitochondrial Trachemys lineages: (1) T. venusta, (2) T. ornata + T. yaquia, (3) T. grayi, (4) T. dorbigni + T. medemi, (5) T. gaigeae + T. scripta, and (6) West Indian Trachemys. These six mitochondrial lineages constitute a well-supported clade. Each mitochondrial Trachemys lineage is corroborated by our nuclear markers. For T. gaigeae another mitochondrial capture event is likely because its mitochondrial genome is sister to T. scripta, although T. gaigeae is deeply divergent in nuclear markers and resembles Mexican, Central and South American Trachemys species in morphology, sexual dimorphism and courtship behavior. The two subspecies of T. nebulosa and many Mexican and Central American subspecies of T. venusta are not clearly distinct in our studied genetic markers. Also, the putatively diagnostic coloration and pattern traits of the T. venusta subspecies are more variable than previously reported, challenging their validity. Our analyses fail to identify T. taylori as a lineage distinct from T. venusta and we propose to assign it as a subspecies to the latter species (Trachemys venusta taylorinov. comb.).
... One important application is the clarification of taxonomic controversies by sequencing name-bearing type material (e.g., Kehlmaier et al. 2019Kehlmaier et al. , 2023. A prominent group with many unresolved nomenclatural challenges is the side-necked turtle family Chelidae Gray, 1825 from South America, Australia, New Guinea, and a few eastern Indonesian islands (Georges & Thomson 2010;TTWG 2021). Using historical DNA (hDNA) sequencing, Kehlmaier et al. (2019) generated near-complete mitochondrial genomes (mitogenomes) from type material that resolved a number of nomenclatural questions for Australasian taxa (see also Kuchling 2020;Kehlmaier et al. 2024). ...
... Long-necked turtles of the genus Chelodina Fitzinger, 1826 have a wide distribution across New Guinea and Australia and also occur on the Indonesian islands Timor and Roti. The genus contains 17 currently recognized species in three morphologically divergent clades ranked as subgenera (TTWG 2021). The first species described and the type species (Fitzinger 1826) of the genus and subgenus Chelodina is "Emys longicollis" (= Testudo with C. burrungandjii and follow the lead of the Australian Society of Herpetologists and subsume under C. rugosa sensu lato populations from southern New Guinea and Queensland, Australia (C. rugosa sensu stricto, i.e., in the sense of TTWG 2021 including C. siebenrocki), as well as those from the Northern Territory, Australia, described as C. kurrichalpongo. ...
... Thus, the C. rugosa populations on either side of the Torres Strait were separated only a few thousand years ago, explaining their genetic similarity. Another turtle taxon, Emydura subglobosa subglobosa, has a similar but converse distribution, with substantial populations in southern New Guinea extending to the northern Cape York Peninsula (TTWG 2021). ...
Based on the phylogenetic placement of a near-complete mitogenome sequence of the holotype of Chelodina intergularis Fry, 1915 generated with hDNA approaches, we present evidence for the synonymy of this nominal species with Chelodina rugosa Ogilby, 1890. The type specimens of both taxa are housed in the Australian Museum, Sydney. Scrutinizing historical records, we conclude that the type locality of both taxa is most likely the vicinity of Somerset, at the northern extremity of Cape York Peninsula, Queensland, Australia. We figure and describe both type specimens. Our results support the earlier conclusion that the exceptional arrangement of intergular and gular scutes in the holotype of C. intergularis is an individual aberration.
... Amphibian and crocodilian data were extracted from the IUCN database version 2023.1 (2024). Data regarding Squamata, encompassing lizards and snakes, were sourced from Roll et al. (2017), while details about testudines were acquired from Rhodin et al. (2021). This new version is more detailed and has more defined polygons, excluding areas where the species may not occur. ...
... 2. Ranges maps of Testudines species were taken from "Turtles of the World: Annotated Checklist and Atlas of Taxonomy, Synonymy, Distribution, and Conservation Status (9th Ed.)", by Rhodin et al. (2021). In the acknowledgments, section we thank the author, Anders Rhodin, for sending us digital copies. ...
Understanding spatial variability in ecological and evolutionary patterns is key to Amazonian biodiversity conservation. This study examined taxonomic, phylogenetic, and functional diversity across amphibians and reptiles, assessing the influence of elevation, interrelationships among metrics, and distribution across five Amazon Basin ecoregions, exploring the “cradle” (speciation) and “museum” (lineage preservation) hypotheses. We analyzed 1011 amphibian species from three lineages and 828 reptile species from four lineages. Integrating distribution maps, phylogenies, and trait data, we calculated phylogenetic (PD), functional (FD), and taxonomic (TD) diversity, including mean phylogenetic (PDmntd) and functional (FDmntd) distance to the nearest taxon. We examined spatial regressions between diversity metrics and elevation, assessed correlations among metrics, and compared diversity metrics across ecoregions for each lineage. Diversity metrics across amphibian and reptile lineages reveal distinct geographical patterns related to elevation. Anurans exhibit higher PD, FD, and TD in the western Amazon, while squamates show hotspots at low altitudes. Testudines are linked to major rivers, and crocodilians display high PD near the equator. Anurans and squamates show elevated PDmntd and FDmntd in the Andes, whereas testudines are found in cratonic regions. Significant correlations and notable differences among ecoregions were found, especially in the Andes and low regions of the Amazon Basin. This study highlights the diverse eco‐evolutionary patterns among amphibian and reptile lineages in the Amazon Basin, each exhibiting distinct hotspots distributed across ecoregions. The findings align with the cradle‐museum hypothesis, suggesting that some regions serve as centers of ongoing diversification, others preserve ancient lineages, or serve as both. The cradle‐museum hypothesis should be carefully analyzed, as each taxon presents a distinct pattern. This research underscores the necessity for targeted conservation strategies tailored to distinct ecological and evolutionary dynamics across ecoregions.
... Estudos neotropicais indicam que as tartarugas são comumente afetadas pelo comércio de animais, com mais de 60% de todas as espécies atendendo aos critérios de criticamente ameaçadas, ameaçadas ou vulneráveis da Red List IUCN (e.g. Morgan;Chang, 2018;Nijman;Shepherd, 2007;Rhodin et al. 2017;Sung;Fong, 2018). ...
... Entre os répteis, tartarugas e cágados representam o grupo de vertebrados mais ameaçados do mundo (Liu et al. 2017;Rhodin et al. 2018;Stanford et al. 2020). Das 356 espécies de tartarugas catalogadas no planeta, mais de 60% delas configuram como criticamente ameaçadas, ameaçadas ou vulneráveis na Lista Vermelha da IUCN (Lovich et al. 2018;Rhodin et al. 2017). ...
Introdução: O uso de animais silvestres como pets é uma prática disseminada culturalmente em todo o mundo. Os quelônios neotropicais se destacam por serem frequentemente comercializados, tanto no mercado nacional como internacional. Objetivos: registrar as espécies de quelônios utilizados no comércio de animais de estimação, identificar as regiões onde essa atividade é mais prevalente e avaliar os impactos na conservação das espécies-alvo. Metodologia: realizamos um levantamento bibliográfico entre março e setembro de 2017, utilizando a base de dados Google Acadêmico. Selecionamos 113 estudos, divididos em dois grupos: aqueles que abordaram diretamente o comércio de quelônios; e aqueles que, embora não focassem no uso e comércio, evidenciaram o fluxo global de espécies. Resultados: identificamos 63 espécies de quelônios pertencentes a 10 famílias, registradas para uso e comércio de pets. Essas espécies foram encontradas em cinco regiões do planeta: América Latina, Ásia, Europa, Oceania e América do Norte. Dentre elas, 37 estão listadas na IUCN Red list, abrangendo categorias que vão de Pouco Preocupantes a Criticamente Ameaçadas. Embora uma grande diversidade de quelônios neotropicais tenha sido registrada no comércio de pets, os dados disponíveis ainda são insuficientes para avaliar a extensão dessa atividade. Conclusão: Observamos uma demanda significativa em regiões onde o comércio é culturalmente enraizado ou em áreas economicamente desenvolvidas, com a Ásia e América Latina destacando-se como os principais centros da rota do comércio internacional. Portanto, são necessárias mais pesquisas etnobiológicas para direcionar estratégias de conservação mais eficazes para as espécies alvo do comércio.
... For instance, such a method may not be practical for monitoring the critically endangered species, Giant South American River Turtle (Podocnemis expansa (Stanford et al., 2020), widely distributed in South America. This species occurs across seven countries in a total area of almost 3 million squared kilometers (Forero-Medina et al., 2019;Rhodin et al., 2021) and is the subject of various conservation projects/programs at local scales. ...
... In species of large turtles that appear on the critically endangered species lists, such as P. expansa (Stanford et al., 2018(Stanford et al., , 2020, P. unifilis, P. sextuberculata and P. erythrocephala, which are classified as vulnerable by IUCN (Rhodin et al., 2021), with many gaps about their ecology, it is imperative that field studies are leveraged to produce more information on habitat use, home range, dispersal, movement patterns and migration (Cunha et al., 2021). In this sense, efficient methods must be used which lead to more individuals marked within a short time, generating more biological information about the studied species, resulting in changes in conservation strategies and actions. ...
The marking or tagging of turtles is a widely used to facilitate the monitoring of population demography, structure, and conservation of species. Even though they are used in many studies of turtle demography, the available methods are not very efficient, except for microchips (Passive Intergraded Transponder/PIT tags); however, the latter is too expensive to be used on a large scale. Here we present a viable, cost-effective tagging alternative that uses a durable plastic cattle tag and pin. Turtles in the genus Podocnemis were tagged in the Lower-Amazon region, west of the state of Pará, Amazon, Brazil. This method is highly recommended for future work on monitoring and population structure of large species of freshwater turtles. In addition to feasibility, it can be used in the form of citizen science, as the information can be obtained by laypeople and taken to researchers and conservationists. Resumen El marcado o marcaje de tortugas es un método ampliamente utilizado para facilitar el seguimiento de la demografía y estructura de las poblaciones y la conservación de las especies. Aunque se utilizan en muchos estudios de demografía de tortugas, los métodos disponibles no son muy eficaces, excepto los microchips (Passive Intergraded Transponder/PIT tags); sin embargo, estos últimos son demasiado caros para ser utilizados a gran escala. Aquí presentamos una alternativa de marcado viable y rentable que utiliza una marca de plástico duradera para ganado y un alfiler. Se marcaron tortugas del género Podocnemis en la región del Bajo Amazonas, al oeste del estado de Pará, Amazonas, Brasil. Este método es muy recomendable para futuros trabajos de seguimiento y estructura poblacional de grandes especies de tortugas dulceacuícolas. Además de su viabilidad, puede utilizarse en forma de ciencia ciudadana, ya que la información puede ser obtenida por profanos y llevada a investigadores y conservacionistas.
... Colombia, por estar ubicada en la zona tropical, registra altos índices de diversidad de especies de reptiles, considerándose como uno de los países con mayor biodiversidad de este grupo en el planeta (1). Con relación a las especies de tortugas, cuenta con 33 especies y 2 subespecies y por tanto juega un papel preponderante en su estudio y conservación (1)(2)(3)(4). No obstante, existe evidencia que demuestra que las poblaciones de tortugas en el mundo, y a nivel local, están disminuyendo debido a actividades antrópicas como la cacería, la pérdida de hábitat, el tráfico ilegal, la introducción de especies y el cambio climático (5)(6)(7)(8). ...
The red-footed tortoise (Chelonoidis carbonarius) is a reptile species, categorized as vulnerable in Colombia, which is present in the lowlands of different geographic regions of the country. This report seeks to demonstrate the finding of lesions compatible with burns and malformations found in free-living red-footed tortoises in the Colombian Orinoco region. Five localities were evaluated in the departments of Arauca and Casanare, in which 176 captures were carried out. In addition, an analysis of the relationship between lesions and the cover and productive activities present in each area was carried out. In 39 cases, macroscopic findings of shell lesions were reported and documented (22 %). In most cases, macroscopic lesions were described as shell and plastron malformations. Other lesions observed were those caused by burns 23.07 % (n = 9). The highest proportion of individuals with burns was found in mixed mosaics (agriculture and livestock), while malformations were more frequent in productive livestock.
... In addition, xenocommunity formation through invasion of turtle species is already reported from different countries and regions (Ferri et al. 2020). Thus, considering the climatic condition in South Korea is similar to the areas in native distribution range of M. sinensis (Rhodin 2021;GBIF 2023), its invasion here can be naturalized easily. Although M. sinensis is reported from all over the country (GBIF 2023; Figure 1B), the success of invasion of this species in Korea remained unclear mainly due to lack of data on its breeding in the local environment. ...
Invasive species are a growing global concern. Modern transportation and the pet trade are facilitating the spread of invasive species. In particular, the global trade of freshwater turtles remains prevalent, with a significant emphasis on their utilization as pets. Aligning with other parts of the world, many recent studies reported a number of alien turtle species in the wild in Korea. However, knowledge of their local establishment and natural breeding is still very limited. In the current study, we report the first natural breeding of Mauremys sinensis in the wild in South Korea. The external features of the observed individual and egg characteristics confirmed its identification. The individual took around 70 minutes to build the nest, lay eggs, and cover up the nest with the soil that it dug from the nest. We recorded a clutch size of ten eggs. The rigid-shelled eggs had an average elongation of 1.82 mm, smaller than M. reevesii. Thus, we confirm the natural breeding and local establishment of M. sinensis in South Korea. Considering previous reports, this finding is significant for understanding both potential competition and putative hybridization with the native species, especially M. reevesii, the endangered native freshwater turtle species in Korea.
... Testudines currently contains 357 recognized species, over half (51%) of which are considered globally threatened. This makes turtles and tortoises one of the most threatened groups of vertebrates (7). Members of this order can be roughly divided into aquatic, semi-aquatic, and terrestrial species. ...
The gastrointestinal (GI) microbiome of chelonians (testudines) plays an important role in their metabolism, nutrition, and overall health but the GI microbiome of three-toed box turtles (Terrapene carolina triunguis) has yet to be characterized. How the GI microbiome responds to rapidly rising environmental temperatures has also not been studied extensively in ectotherms, specifically chelonians. In this study, twenty (20) T.c.triunguis were split into control and experimental groups. The experimental group experienced 4.5°C increases every two weeks while the control group stayed at a constant ambient temperature (24°C) through the entirety of the experiment. Before each temperature increase, all turtles had cloacal swab samples taken. These samples underwent DNA extraction followed by 16S rRNA gene sequencing and microbial community analyses. Differences in diversity at the community level in the controls compared to the experimental groups were not statistically significant, indicating microbiome resilience to rapid temperature changes in T.c.triunguis, although some differentially abundant lineages were identified. Interestingly, an amplicon sequence variant belonging to the Erysipelothrix spp. was exclusively enriched in the highest temperature group relative to controls. Overall, our work suggests that there may be an innate robustness to rapid temperature swings in the microbiome of T.c.triunguis which are native to temperate North America. Despite this resilience, Erysipelothrix spp. was enriched at the highest temperature. Phylogenetic analysis of this amplicon variant showed that it is a close relative of Erysipelothrix rhusiopathiae, a pathogen of zoonotic importance associated with both wildlife and livestock.
... Chelonians are the most threatened vertebrate order, with 51.3% of all known species considered globally threatened (critically endangered, endangered, or vulnerable) and 20.4% critically endangered (Buhlmann et al. 2009;Rhodin et al. 2021). Infectious diseases have been associated with an increasing number and frequency of morbidity and mortality events in reptiles generally and chelonians specifically (Fey et al. 2015;Adamovicz et al. 2018;Zhang et al. 2018;Waltzek et al. 2022). ...
The order Onygenales contains multiple fungal pathogens that affect free-ranging and zoo-housed reptilian species. Emydomyces testavorans, an onygenalean fungus associated with skin and shell disease, has been sporadically detected in aquatic chelonians. Because of the recent discovery of this organism, little is known about its prevalence in free-ranging chelonians. The objective of this study was to perform surveillance for E. testavorans in six free-ranging aquatic and terrestrial chelonian species in Illinois, USA: Blanding's turtles (n=437; Emydoidea blandingii), painted turtles (n=199; Chrysemys picta), common snapping turtles (n=35; Chelydra serpentina), red-eared sliders (n=62; RES; Trachemys scripta elegans), eastern box turtles (n=73; Terrapene carolina carolina) and ornate box turtles (n=29; Terrapene carolina ornata). Combined cloacal-oral swabs (COSs) or shell (carapace and plastron surfaces) swabs were collected from 2019 to 2021 and tested for E. testavorans using quantitative PCR. The PCR detected E. testavorans in COSs of an adult male, subadult female, and juvenile male Blanding's turtle (0.6%; 95% confidence interval [CI], 0.2-1.9%) and a shell swab from an adult female RES (1.6%; 95% CI, 0-8.7%). Shell lesions consistent with E. testavorans infection were present in two of the positive Blanding's turtles. These results document the rarity of this pathogen on the landscape in Illinois. Additional studies should determine this pathogen's impact on individuals and clarify its significance for conservation efforts of Blanding's turtle, in which E. testavorans has not been reported previously.
The Neotropical region is considered a biodiversity hotspot for reptiles, with eight families of terrestrial and freshwater chelonians. Parasites are of great importance to aquatic ecosystems and are essential to host communities. They help understand the patterns and phylogenetic relationships of their hosts and act to control populations. A literature survey on helminth parasites of chelonians in the Neotropical region was conducted, examining the most commonly found groups of helminths, the most parasitized hosts, compiling their biogeographical and political distribution and recording the parasite fauna of Phrynops geoffroanus in the state of Paraíba, northeastern Brazil. Considering the literature from 1850 to 2024, 202 helminth taxa were recorded. The Mesoamerican dominion had the highest number of helminth taxa, and Brazil was the political unit that recorded the most helminth taxa, followed by Mexico. Nematoda was the group with the highest number of taxa and occurred in all biogeographical units, with the species Spiroxys contortus being the most commonly found, followed by Trematoda, represented by the most commonly found species, Nematophila grandis. Hosts from the Chelidae family had the highest number of helminth taxa, followed by the Kinosternidae family. The most parasitized host species were Chelonoidis denticulatus and Phrynops hilarii. For the host Phrynops geoffroanus , the first occurrence of the nematode helminth Spiroxys contortus was recorded. This is the first study to include all parasitic helminths of terrestrial and freshwater chelonians in the Neotropical region, including a new occurrence in a chelonian host in the hinterland of Paraíba, Brazil.
Pleurodiran chelid turtles are represented from the Late Miocene in northeastern and northwestern Argentina by species assigned to Phrynops sensu stricto = Phrynops geoffroanus complex. In the northeastern region, these turtles include the extinct species Phrynops paranensis (Wieland, 1923) from the Ituzaingó Formation, Entre Ríos Province. On the other hand, from the Late Miocene of northwestern Argentina, Phrynops specimens involve
unnamed species coming from El Morterito (Cajon Valley, Catamarca Province) and Andalhual´a (Tiopunco, Manta María Valley, Tucum´an Province) formations. In this contribution, a new and relatively complete specimen assigned to Phrynops sensu stricto (Phrynops sp.) from the upper levels of the Palo Pintado Formation exposed in Quebrada Salta (Salta Province) is described and compared. The particular morphology of the specimen analyzed, different both from Phrynops paranensis, the only extinct species recognized for the genus, as well as
from the current species of the genus, suggests the presence of at least two taxa in the Late Miocene of Argentina, one limited to the northeastern region (Phrynops paranensis) and another as yet unnamed from the northwestern region. Sedimentological analysis and fossil evidence analyzed for the sector strongly suggest the development of a tropical climate during the deposition of the Palo Pintado Formation. Considering that Phrynops sensu stricto spp. currently inhabiting freshwater lowlands in tropical to humid temperate climates, the presence of this aquatic species is consistent with the paleoenvironmental conditions previously interpreted for this unit.
Turtles are organisms with high vulnerability due to the impact on their ecosystems and the lack of biological knowledge. Hematological studies in chelonians are limited by the absence of specific techniques-procedures; for this reason, adopted methodologies are not always appropriate. The study aim was to compare variations in fixatives concentrations, Giemsa staining versus exposure times on blood smears from Trachemys venusta venusta, Staurotypus triporcatus and Rhinoclemmys areolata. The comparison of pure methanol (99.8%) against denatured ethanol (70%) was carried out with exposure of 0.5, 1.0, 5.0 and 10 min. In the staining tests with Giemsa (10%), the exposure of 1, 5, 10 and 20 min was used and with the Giemsa stock solution the staining of 5, 10, 20 and 30 seconds was tested too. The results shown that increasing the exposure time in methanol, significantly increases the number of cells with damage to the membrane and cellular structure. In the samples with ethanol, low records of atrophy were observed. When 10% Giemsa was used together with the staining increase, a significant decrease in erythrocytes without membrane damage was observed. The employment of Giemsa stock solution rises the cells without damage. The best fixative was the denatured ethanol and staining with 10 seconds in Giemsa stock solution. With the suggested method, it will be possible to obtain high-quality blood cells for studies in basic and applied science as well as in clinical practices.
Aim
We examine the phylogeographic genetic structure of the endangered pig‐nosed turtle Carettochelys insculpta, the last remaining member of a once globally widespread family, now restricted to northern Australia and southern New Guinea, a region with a complex geological and eustatic history. We examine their historical biogeography, demographic history and genetic status of threatened populations.
Location
Northern Australia, Southern New Guinea.
Methods
We reconstruct phylogenetic relationships and patterns of genetic diversity using a genome‐wide dataset of 15,081 single nucleotide polymorphisms and two mitochondrial loci from samples spanning the full species' range.
Results
The Australian, Papua New Guinea and Indonesian Papua turtles are recovered as three distinct lineages; the Australian lineage diverged from the New Guinea lineages ca 660 Kya, while the Papua New Guinea and Indonesian Papua Province lineages diverged ca 564 Kya. Although the fossil record shows that C. insculpta has been a long‐standing representative of the Australia and New Guinea fauna (since at least the Miocene), extant lineages diverged later in the Middle Pleistocene. Both the Australian and Papua New Guinea lineages were likely shaped by bottlenecks, isolation and genetic drift, which in the Australian lineage greatly reduced effective population sizes to 48–88.
Main Conclusions
The contemporary genetic structure of C. insculpta is most consistent with a vicariance model whereby a large interchanging population occupying northern Australia and New Guinea came to be fragmented and diverged into Australian, Papua New Guinea and Indonesian Papua lineages. Subsequent dispersal via paleodrainages of the submerged continental shelf under the influence of Pleistocene sea‐level change is thought to have been impeded by the isolation of the Akimeugah and Arafura Basins. All populations of the Australian lineage show low genetic diversity without contemporary gene flow, suggesting they are vulnerable to inbreeding and reduced fitness, requiring the consideration of genetic rescue.
Gray described the turtle species “Damonia ? crassiceps” in his Supplement to the Catalogue of Shield Reptiles; the inclusion of a question mark in the binomial apparently indicated some uncertainty about the generic assignment of the species. He based the description solely on iconotypes, consisting of a series of three watercolor illustrations from Thomas Hardwicke commissioned by naturalist John Reeves and bequeathed to the British Natural History Museum (NHM) as part of a large collection of zoological artworks. The physical specimen, from which the illustrations of D. crassiceps were created, has not been located and likely was never deposited in a museum collection.
Based on a close examination of three copies of Reeves' watercolors, our analysis shows that these illustrations do not represent the junior synonym D. subtrijuga or any other species in the genus Malayemys. Instead, comparisons with Red-necked Pond Turtle (Mauremys nigricans) indicate that the illustrations depict an adult male of this species. First known as Emys nigricans, Gray provided a brief description of the species based on a nearly complete juvenile shell provided by John Reeves, and later offered additional details, although specimens of this species remained rare and were often confused with other species. Therefore, due to the insufficient material for comparison and the ontogenetic sexual dimorphism of Mauremys nigricans, Gray described the illustrations that Hardwicke obtained from Reeves as a new species.
We conclude that the nomen D. crassiceps is not applicable to any populations in the genus Malayemys and should be removed from synonymy with M. subtrijuga. Instead, D. crassiceps must be considered a junior subjective synonym of Mauremys nigricans.
Conclusions. There is no evidence that the specimens presented by Liu et al. (2024) as type material of T. axenaria are part of the original type series of that species. The obvious fact that specimen labels have been secondarily attached and changed raises serious doubts about their authenticity and identity. We therefore refute that any of these specimens represent syntypes of T. axenaria. The purported mtDNA sequences cannot be firmly associated with the type material either. In the light of the evidence presented, the neotype designation for T. axenaria by Gong et al. (2022) stands, and Pelodiscus huike Liu, Fu, Ma, Zhou, Blanck, Zhou, Xiao & Mo, 2024, based on the same name-bearing type (JNU 20210001), is an objective junior synonym of Trionyx axenaria Zhou, Zhang & Fang, 1991 (ICZN 1999: Article 61.3.4).
A new species of chelid turtle ( Calvarichelys coloniensis gen. et sp. nov.) from the Upper Cretaceous La Colonia Formation (Chubut Province, Argentina) is described here. This species is represented by an almost complete skull and a complete lower jaw. Detailed description and comparison of the species enables differentiation of this species from the rest of stem and crown group Chelidae. In particular, this new chelid is characterized by an almost non‐existent temporal emargination with a lateral emargination that reaches the parietals but leaves an extended skull roof with almost parallel margins. Also, this new species is similar to some Australasian (e.g. Emydura macquarii , Elseya dentata ) and South American ( Platemys platycephala ) short‐necked chelids and some extinct chelids (e.g. Mendozachelys wichmanni ) in the presence of a fused and hooked mandibular symphysis. Three types of total evidence analysis (implied and equal weights using maximum parsimony, and Bayesian inference) were carried out to evaluate the phylogenetic relationships of the new species of turtle presented here. In all analyses, C. coloniensis is recovered inside a clade with other Cretaceous South American species such as Mendozachelys wichmanni , Palaeophrynops patagonicus , Lomalatachelys neuquina and Bonapartemys bajobarrealis . However, in the cladistic analyses the mentioned clade is recovered inside crown‐Chelidae as the sister group of the short‐necked Australasian chelids, while in the Bayesian inference it is located outside crown‐Chelidae, being the sister group of Prochelidella spp. + crown Chelidae. These differences highlight the impact of the methodology used (e.g. parsimony, Bayesian inference) on the results.
A new Early Sarmatian s.l. (Volhynian, late Middle Miocene) vertebrate assemblage is described from the
outskirts of the Forecarpathian Basin, which at that time was an integral part of the Eastern Paratethys. The
studied fossils come from greenish-grey and black silts and clays of the Kharalug locality (Rivne Oblast,
Ukraine), which palaeogeographically is situated nearby to the north-eastern coast of the basin. The studied
sample comprises 115 specimens, mainly of fish bones, whereas reptiles (turtles) and birds (ducks) are
represented by a single bone each. The fish remains have been assigned to five genera and three families
(Cyprinidae, Siluridae, and Percidae), of which percids are the most abundant being represented by pikeperches (Leobergia, Sander) and perches (Perca). The studied Kharalug assemblage is likely mixed, its
taxonomic composition is relatively poor, and, although less diverse, demonstrates some similarity to
assemblages of the subsequent (Bessarabian) stage of the Eastern Paratethys. The ecological features of
the revealed taxa along with the geological and palaeogeographical contexts suggest a shoreside freshened
palaeoenvironment for the Kharalug locality, possibly a lagoon or a lake at some distance from the coastline. The obtained results may contribute to the reconstruction of local Miocene palaeoenvironments within the
Paratethyan realm.
The mitochondrial genome of three Trachemys medemi was sequenced and annotated for the first time. The mitochondrial genome is a circular DNA molecule of 16,711–16,810 bp in size, with 60.9% AT content. It includes 13 protein-coding genes, two rRNA genes, 22 tRNA genes, and the non-coding control region. The genome composition is characterized by a positive AT skew (0.123) and a negative GC skew (-0.342). Phylogenetic analyses based on complete mitogenomes, which lack some Trachemys species, placed T. medemi as sister to T. venusta. Phylogenies from the same dataset, but including available shorter mtDNA information for most Trachemys species, recovered T. medemi as sister to T. dorbigni, and this clade was sister to T. venusta, T. yaquia, and T. ornata. The newly obtained data are valuable for future mitogenomic investigations on Trachemys. Furthermore, our results underline the impact of incomplete taxon sampling.
We present records of winter activity of non-native turtles, especially Trachemys scripta, the most common alien turtle in Romania. This species was observed basking in urban park lake settings in the winter months at the beginning of 2024. Trachemys scripta individuals were active during atypically warm days, but not during alternating cold spells with snowfall and ice formation; on warm days, turtles were also observed in the proximity of persisting lake ice. Other aquatic turtle species emerged from hibernation at the end of the winter, when temperatures were considerably higher, nearing 20 °C.
Direct exploitation and wildlife trade pose significant threats to global biodiversity, particularly impacting reptiles, such as tortoises, which are highly vulnerable. Moreover, the releases of captive-held animals into the wild can lead to potential negative consequences, including genetic introgression, disease transmission, and parasite spread. Therefore, diagnostic assessments are essential to evaluate the impact of release practices. In this study, we analyzed the shell morphology of Testudo graeca tortoises to assess the effectiveness of morphological analysis in identifying captive-introduced tortoises and quantifying tortoise releases in SE Spain. Despite being illegal, the cultural tradition of keeping and breeding tortoises at home persists in this region. Principal component analyses identified significant morphological differences between captive and wild tortoises. Captive tortoises generally exhibited larger shell sizes and greater morphological variability compared to wild tortoises. Accordingly, linear discriminant analyses accurately identified approximately 99% of wild tortoises, but the identification of captive tortoises was only 50% accurate because some captive tortoises show shell morphologies identical to wild ones. These results likely reflect the diverse origins and growth conditions of captive tortoises. Although this is likely an underestimation, our approach classified 7% of 125 wildlife tortoises across 13 natural sites such as captive-introduced tortoises. These findings highlight the potential impact of tortoise releases in wild populations and underscore the value of morphological analyses as an initial tool for diagnosing such impacts. Furthermore, integrating genetic and isotopic methods could further enhance the precision of these assessments.
Biological communities are structured by a variety of biotic and abiotic relationships, whose understanding forms the basis for effective conservation. Among the myriad factors influencing community dynamics, resource partitioning stands out, potentially enriching ecosystem complexity but also carrying risks for conservation if disregarded. In this study, we investigated intersexual and ontogenetic niche differences among populations of the West African softshell turtle Trionyx triunguis in Liberia, Cote d'Ivoire, Ghana and Nigeria. We observed that these distinct populations exhibited similar habitat preferences, favouring large rivers with abundant riverbank and aquatic vegetation, and muddy substrates. Disparities in habitat preferences were evident among populations and across various life stages, indicating the adaptability of the species. We found that the species was active throughout the year, but most of our sightings and captures occurred during the wet season. In light of the species' vulnerability to overhunting, our research findings provide important data on the ecology of this species that can assist in its effective conservation across all life stages.
In this work, the plastron formula and the diversity index associated with the allometric condition are established for the Chelidae turtle Phrynops geoffroanus (Schweigger, 1812), known as “Geoffroy´s sidenecked turtle”. The species has a wide distribution in South America, living in aquatic environments such as rivers,
streams, and lakes, in natural and urban environments. For the morphometric analyses, the following were calculated: standard error, class intervals, sample standard deviation, principal component analysis, and allometry. When evaluating the morphometric dependence, r = 0.85 was obtained, which allowed us to verify the allometric classification Y, the growth rate K, and the proportion of growth b for each segment that composes the length of the plastron (LP). Thus, the calculated morphometric set demonstrates that the plastron formula can serve as a diagnostic character for Phrynops geoffroanus. We inferred from this study that the plastron formula can be maintained even in conditions of high environmental degradation.
The Pacific Lowlands (PL) of Mexico hosts a rich diversity of amphibians and reptiles, comprising 326 native species (76 amphibians and 250 reptiles) across 45 families. This region is significant from a biodiversity standpoint, accounting for 23.3% of Mexico’s total amphibian and reptile species, with 30 species being endemic to the PL. Notably, the PL ranks sixth in amphibian and reptile diversity among Mexico’s fourteen biogeographic provinces. The species composition indicates a complex biogeographic relationship for the province, which shares the highest percentages of species with the neighboring Transition Zone provinces, while also acting as a vital corridor for species adapted to varied environmental conditions. Despite its diversity, 24 species in the PL are of conservation concern, highlighting threats from habitat loss, urbanization, and the impacts of introduced species in the province. Our findings underscore the ecological significance of the PL and the urgent need for conservation efforts to protect its unique biodiversity.
The Podocnemidid Amazon river turtles are the region´s most conspicuous and culturally important species. Intense exploitation led populations of the largest species, such as the Giant South American River Turtle (Podocnemis expansa), to drastic declines over time. Since 1979, the main nesting areas of the Giant South American River Turtles have been monitored and protected by the Brazilian Government through the Amazon Turtle Program (PQA). This study analyzed the PQA database from 1979 to 2022 to identify population trends in 11 major nesting areas covered by PQA. We modeled the data on the number of hatchlings for each location and the whole dataset by linear, general additive, and general linear models using Poisson and Negative Binomial distributions. In six areas, populations increased over time with statistical significance; three significantly declined, and two showed wide variation among years and no significant trend. For 43 years, there was an increase of 95% in the total sum of hatchlings from the major nesting sites included in this study. The PQA, working with partners, especially riverine communities, has been efficient in recovering populations of P. expansa in Brazil. The recent population recovery is essential to orientate conservation strategies that might be maintained or improved in areas where the population declined. The major threats causing synergistic impacts are growing in the Amazon, such as dam constructions, deforestation, mercury, and pesticide contamination. Therefore, we emphasize the need to estimate the number of nests correctly, address the impacts of different causes of embryo mortality, and maintain conservation efforts to ensure species conservation, especially in countries with no Government conservation programs.
The Mesoamerican Slider Trachemys venusta ocurr from several Central American countries to Mexico. The first case of hypomelanism in a captive-born specimen is formally reported. In this chromatic aberration or pigmentary anomaly resulting from genetic factors, the dark tones of specimen’s body with carapace length 77 mm and undetermined sex, were observed pale (discolored), except for the eyes which retained normal coloration, were the patterns of lines and ocelli in yellow and green tones also persisted. Additionally, the plastron exhibited a lighter yellow hue compared to the typical coloration. In the wild, such color abnormalities can be considered a disadvantage as they contrast with the specimen in aqueous murky environments, making it more susceptible to detection and predation compared to specimens with normal coloration.
The Paraná River Basin has an area of 2.6 million km2. The river has a mean annual discharge of 19,700 m3/s, the third largest in South America after the Amazonas and the Orinoco. It contains huge areas of wetlands (e.g., the Pantanal) and large floodplains along its entire course. The main river runs for 3965 km from the headwaters of the Rio Grande in the humid highlands of the Serra do Mar and Serra da Mantiqueira, crossing several ecoregions like the Atlantic Forest, Cerrado, Chacoan forests, Pampean plains, and the Paraná flooded savanna, finally flowing into one of the largest estuaries in the world: the Río de la Plata. In this chapter, we describe the geology, hydrology, biodiversity, and environmental problems of seven rivers of this large basin: Upper Paraná, Middle and Lower Paraná, Paranaíba, Grande, Tietê, Paranapanema, and Iguaçu rivers; the Paraguay and the Andean tributaries are discussed in other chapters. Since the 1970s the upper basin has experienced a vertiginous hydropower development with almost 800 dams constructed until today, which generate strong environmental impacts. The lower basin is still unregulated and with the Paraguay River it forms a 3500-km free-flowing riverine axis with intact floodplains that is still the habitat of many migratory fish species that sustain highly productive fisheries.
This study presents zooarchaeological and ancient DNA (aDNA) analyses of the remains of a non-local gopher tortoise (Gopherus polyphemus) recovered from a ca. 1850s–1861 privy in New Orleans, Louisiana. This tortoise pre-dates the known import of these animals to the city beginning in the 1870s, raising questions about how and why this individual was brought to New Orleans. To address these questions, we use a median-joining network and maximum-likelihood tree to identify the haplogroup to which the archaeological tortoise likely belonged, and we combine these results with historical data to suggest a likely origin point in the western portions of the species' range. We place these findings within the fabric of the historical development of New Orleans, which nearly tripled in population from 1830 to 1860 and which saw a concomitant import of a diverse array of foods to meet consumer demand. Ultimately, we argue that the gopher tortoise is likely the result of entrepreneurialism, experimentation, and creative attempts to develop reliable food supply that fit within New Orleans’ cuisine.
The Grán Chaco is a semiarid and hot area roughly between East Andes and the Paraguay river and from Bolivia to Argentina. The Southern Chaco is drained by four major rivers. The Pilcomayo and Bermejo rivers run almost parallel from their headwaters in the Andes (3700–4600 m a.s.l.) and after about 1300 km, reach their mouths in the Paraguay River. The Salado flows from the Cordillera Oriental (∼5400 m a.s.l.) and after ∼2200 km, reaches the Paraná River. The endorheic Salí-Dulce originates at ∼2000 m a.s.l. mainly in the Pampean hills (adjacent to the Andes) and flows into the “Mar Chiquita” (14,000 km3). The combined basin of these rivers covers a surface approximately the size of France. The rivers cross different ecoregions, from High Andes and Puna to humid heterogeneous mountain (Yungas jungle), high valleys, and the Gran Chaco plain. They have similar and rich fauna and flora but also unique characteristics due to the different geological units they traverse. These rivers have great importance for the pre-Columbian cultures that persist to the present, as they are the main watercourses in this economically important region shared by three different countries.
Turtles are an evolutionarily unique and morphologically distinctive order of reptiles, and many species are globally endangered. Although a high diversity of adenoviruses in scaled reptiles is well-documented, turtle adenoviruses remain largely understudied. To investigate their molecular diversity, we focused on the identification and characterisation of adenoviruses in turtle-derived organ, swab and egg samples. Since reptile circoviruses have been scarcely reported and no turtle circoviruses have been documented to date, we also screened our samples for circoviruses. Host−virus coevolution is a common feature of these viral families, so we aimed to investigate possible signs of this as well. Two screening projects were conducted: one on Brazilian samples collected from animals in their natural habitat, and the other on Hungarian pet shop samples. Nested PCR systems were used for the detection of adeno- and circoviruses and purified PCR products were Sanger sequenced. Phylogenetic trees for the viruses were reconstructed based on the adenoviral DNA polymerase and hexon genes, circoviral Rep genes, and for the turtle hosts based on mitochondrial cytochrome b amino acid sequences. During the screening, testadeno-, siadeno-, and circovirus strains were detected. The circovirus strains were classified into the genus Circovirus, exhibiting significant evolutionary divergence but forming a monophyletic clade within a group of fish circoviruses. The phylogenetic tree of turtles reflected their taxonomic relationships, showing a deep bifurcation between suborders and distinct monophyletic clades corresponding to families. A similar clustering pattern was observed among the testadenovirus strains in their phylogenetic tree. As a result, this screening of turtle samples revealed at least three new testadenoviruses, including the first sea turtle adenovirus, evidence of coevolution between testadenoviruses and their hosts, and the first turtle associated circoviruses. These findings underscore the need for further research on viruses in turtles, and more broadly in reptiles, to better understand their viral diversity and the evolutionary processes shaping host–virus interactions.
Biological communities are structured by a variety of biotic and abiotic relationships, whose understanding forms the basis for effective conservation. Among the myriad factors influencing community dynamics, resource partitioning stands out, potentially enriching ecosystem complexity but also carrying risks for conservation if disregarded. In this study, we investigated intersex-ual and ontogenetic niche differences among populations of the West African softshell turtle Trionyx triunguis in Liberia, Cote d'Ivoire, Ghana and Nigeria. We observed that these distinct populations exhibited similar habitat preferences, favouring large rivers with abundant riverbank and aquatic vegetation, and muddy substrates. Disparities in habitat preferences were evident among populations and across various life stages, indicating the adaptability of the species. We found that the species was active throughout the year, but most of our sightings and captures occurred during the wet season. In light of the species' vulnerability to overhunting, our research findings provide important data on the ecology of this species that can assist in its effective conservation across all life stages.
Chelonoidis carbonarius is host to a great diversity of endoparasites. This research aimed to identify and taxonomically classify the parasitic forms of endoparasites found in the feces of C. carbonarius using coproparasitological methods. In total, 38 fecal samples were collected from animals captured in the municipalities of Cuiabá (n = 23) and Jataí (n = 15) in the Brazilian Ceraado. Fecal samples were submitted to at least one of the following techniques: Willis-Mollay flotation technique, zinc sulfate centrifugal flotation technique, and spontaneous sedimentation of Hoffman, and Pons, and Janer. Overall, 86.85% (33/38) of animals were positive in at least one of the diagnostic techniques. Of the 38 samples used, 50% of the animals were captive and 50% of the animals were free-living. Cysts, oocysts, and parasitic eggs were identified, as follows: Chapiniella spp. (65.78%; n = 24), Sauricola spp. (31.57%; n = 12), Ascaroidea (15.78%; n = 6), Oxyuridae (2.63%; n = 1), Trematoda (2.63%; n = 1), Acanthocephala (2.63%; n = 1), Balantidium spp. (39.47%; n = 15), Eimeria spp. (21.05%; n = 8), and Nyctotherus spp. (2.63%; n = 1). The study showed that both captive and free-living C. carbonarius are often parasitized by different endoparasite species, with nematode eggs being the most common.
Syria is home to a wide range of ecosystems and landscapes that support a variety of animal species, including reptiles. Currently, Syria hosts nine species of chelonians (turtles and tortoises) from six different families, making its family-level diversity remarkable for the Mediterranean and the Middle East. We conducted a comprehensive review of existing literature, database information, and museum records, and incorporated new field data collected between 2019 and 2023 to document the distribution and conservation status of chelonians in Syria. As a result, we present an updated species list, accompanied by relevant information and occurrence maps for each turtle and tortoise species found in the country. Our investigation has yielded a total of 321 distribution records for Syrian chelonians (including nests of marine species), 105 of which are new. In addition, we verified 18 sites previously documented in the literature. Among the most frequently recorded species is Testudo graeca terrestris Forskål, 1775. In addition, for the first time, we have systematically evaluated the records of two marine turtle species that use Syrian coasts as nesting sites. This study is the most comprehensive and up-to-date source of information on the distribution and biogeography of chelonians in Syria, encompassing both historical and current geographic records. In addition, our data provide a zoogeographic overview and a substantial dataset of distribution information that can be used for subsequent analysis of macroecological patterns, distribution patterns, and conservation efforts related to this group of reptiles.
We report on the geologically youngest occurrence of the softshell turtle family Trionychidae in Europe, from middle Calabrian (Emilian) strata cropping out at Montalto, Pisa Province (Tuscany, central Italy). This record indicates that the softshell turtles survived well past the glacial pulse at ca. 1.8 Ma. That the most recent finds of Trionychidae all over Europe come from mainland Italy further evokes the role of the Apennine peninsula as a refugium for humid-dwelling herpetofaunas through most of the Plio-Pleistocene. Reduced humidity associated with the intensified cool stages at the beginning of the Early–Middle Pleistocene Transition may have been behind the demise of the last European softshell turtles.
One of the challenges in the management of Kinosternon scorpioides is related to egg quality, since mineral deficiencies affect egg production. The aim of this study was to evaluate the ultrastructure and mineral composition of eggshells, and their relation to K. scorpioides embryonic skeletogenesis. Eggs were collected, incubated and distributed into three groups: 1- pre-ossification (PO); 2- bone ossification (BO); and 3- complete ossification (CO). Nine samples were included in the PO and BO groups, and six in the CO group, for a total of 24 eggs. The morphological and mineral analyses of the eggs were performed by scanning electron microscopy coupled with energy-dispersive spectroscopy. The embryos from the BO and CO groups were cleared with potassium hydroxide and stained with alcian blue and alizarin red to observe osteogenesis. The results showed a significant difference (p < 0.05) in the amount of shell calcium between the PO (63.14%) and CO (41.95%) groups, as well as in the shell thickness between the same groups (PO: 305.38 ± 60.27 μm; CO: 197.67 ± 40.28 μm), and BO (289.56 ± 55.87 μm) and CO groups. It is suggested that the gradual mobilization of calcium by the embryo is reflected in the decrease in shell thickness. In addition, the first structures to ossify were the dermatocranium and mandible. The CO group, in which the individuals all had established bone structures, had the lowest calcium concentration of eggshells. Approximately 21% of the shell calcium was absorbed, which suggests participation in the embryo skeletogenesis. Understanding calcium dynamics as they relate to shell quality and embryonic development of K. scorpioides highlights the importance of including this mineral in the diet of breeding females and, consequently, in improving offspring production.
For the Inventory of the Herpetofauna of Mexico, a total of 1,422 native herpetofaunal species are reported so far (892 endemic, 62.7%), of which 430 (30.2%) are amphibians (15 families and 58 genera) with 299 (69.5%) endemic species, and 992 (69.8%) reptiles (41 families and 154 genera) with 593 (59.8%) endemic species.
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