Sternotherus Odoratus Research Articles

Chondrocranial anatomy of Testudo hermanni (Testudinidae, Testudines) with a comparison to other turtles.

Using histological cross-sections, the chondrocranium anatomy was reconstructed for two developmental stages of Hermann's tortoise (Testudo hermanni). The morphology differs from the chondrocrania of most other turtles by a process above the ectochoanal cartilage with Pelodiscus sinensis being the only other known species with such a structure. The anterior and posterior processes of the tectum synoticum are better developed than in most other turtles and an ascending process of the palatoquadrate is missing, which is otherwise only the case in pleurodiran turtles. The nasal region gets proportionally larger during development. We interpret the enlargement of the nasal capsules as an adaption to increase the surface area of the olfactory epithelium for better perception of volant odors. Elongation of the nasal capsules in trionychids, in contrast, is unlikely to be related to olfaction, while it is ambiguous in the case of Sternotherus odoratus. However, we have to conclude that research on chondrocranium anatomy is still at its beginning and more comprehensive detailed descriptions in relation to other parts of the anatomy are needed before providing broad-scale ecological and phylogenetic interpretations.

Comparative data on the blood leukocyte composition of semi-aquatic turtles from the Samara Zoo

The leukocyte blood count of 16 species of five families of semi-aquatic turtles from the Samara Zoo was determined. A comparison of the leukogram of representatives of two genera of the family Emydidae revealed a reduced proportion of heterophils and an increased proportion of basophils in Graptemys (G. pseudogeographica, G. nigrinoda) compared with Terrapene (T. triunguis, T. ornata). The leukocyte profile of Cuora mouhotii (Geoemydidae) was characterized by an increased content of heterophils, which showed a higher activation of innate immune responses. The most similar in leukocyte composition are the species of the Kinosternidae family of three genera: Kinosternon, Sternotherus and Staurotypus. The clade Trionychia (Trionychidae) differed from the clade Durocryptodira (Emydidae, Geoemydidae and Kinosternidae) by an increased number of heterophils and monocytes, and a low content of eosinophils. The Pleurodira suborder (Chelidae) differed from the Cryptodira suborder (Emydidae, Geoemydidae, Kinosternidae, Trionychidae) by an increased content of agranulocytes. Positive significant correlations of the length of the carapace with the content of heterophils and the values of leukocyte indices (index of the eosinophils and lymphocytes ratio, index of the heterophils and eosinophils ratio, index of the heterophils and lymphocytes ratio) reflecting the increased role of nonspecific resistance of the turtle organism during ontogenesis and negative significant correlations with the content of eosinophils were revealed. The index of the heterophils and lymphocytes ratio, which is an indicator of physiological stress, had the minimum value among the studied species in Sternotherus odoratus (Kinosternidae), the maximum value in C. mouhotii (Geoemydidae).

Trace Amounts of Ranavirus Detected in Common Musk Turtles (Sternotherus odoratus) at a Site Where the Pathogen Was Previously Common.

Ranaviruses are global multi-host pathogens that infect ectothermic vertebrates and cause mass mortality events in some species. In 2021-2022, we surveyed two species of aquatic turtles in a Virginia site where previous research found ranavirus in lizards (Sceloporus undulatus) and turtles (Chrysemys picta picta and Terrapene carolina carolina). We sampled tissues from 206 turtles and tested 249 samples (including recaptures) for ranavirus using qPCR. We detected trace amounts of ranavirus DNA in 2.8% of Common Musk Turtles (Sternotherus odoratus). We did not detect the virus in Eastern Painted Turtles (C. p. picta). The Ct values from animals carrying ranavirus corresponded to positive controls with a concentration of one copy of ranavirus DNA per microliter and likely reflect DNA in the environment rather than ranavirus infection in turtles. Turtles carrying ranavirus DNA came from only one pond in one year. The amount of ranavirus in our study site, as indicated by tissue samples from turtles, appears to have dropped dramatically since previous research conducted over a decade ago. This study represents the first report of ranavirus detected in S. odoratus and contributes to the scarce literature on longitudinal surveys of ranavirus in wild chelonians. We emphasize the need for large sample sizes and multi-year sampling to detect this pathogen in wild populations.

Freshwater turtle climbing abilities: Implications for the design and use of shoreline erosion control structures

Freshwater shoreline modifications can reduce connectivity between aquatic and terrestrial environments, contributing to the decline of freshwater biodiversity. Freshwater turtles may be particularly vulnerable to shoreline modifications because they must access land for essential activities such as nesting, basking, and dispersal. Here, we tested the clinging abilities of three freshwater turtle species (i.e., painted turtles, Chrysemys picta; eastern musk turtles, Sternotherus odoratus; and northern map turtles, Graptemys geographica) to inform design criteria for mitigating the impacts of shoreline modifications on the ability of turtles to perform these behaviours. We tested clinging behavior using a ramp and pulley system with smooth and rough concrete ramps to find the maximum clinging angle for all three species. We found that painted turtles were the weakest at clinging, averaging a maximum clinging angle of 37° on a smooth ramp and 73° on a rough ramp. Eastern musk turtles had an average maximum clinging angle of 45° on a smooth ramp and 87° on a rough ramp. Northern map turtles had an average maximum clinging angle of 41° on a smooth ramp and 87° on a rough ramp. For all three species, surface type had significant effects upon maximum clinging angles, and mass was also statistically significant in affecting the clinging of eastern musk and northern map turtles. As the painted turtles were the weakest clingers and the most ubiquitous species (Van Dijk, 2016), we used this species to validate the clinging trials through volitional climbing tests. Successful climbs peaked at 35° on the smooth ramps and 40° on the rough ramps. To maintain turtle accessibility in areas with these species, future shoreline modifications should be textured and not have slopes that exceed 40°.

Variation and development of the turtle chondrocranium, with a description of the common musk turtle (Sternotherus odoratus, Kinosternidae, Cryptodira, Testudines)

Based on histological cross-sections, the chondrocranium of the common musk turtle (Sternotherus odoratus) was reconstructed, described, and compared with other turtles. It differs from that of other turtle chondrocrania by possessing elongated, slightly dorsally orientated nasal capsules with three dorsolateral foramina, which might be homologous to the foramen epiphaniale, and by having an enlarged crista parotica. Additionally, the posterior part of the palatoquadrate is more elongated and more slender than in other turtles, while its ascending process is connected to the otic capsule by appositional bone. The proportions of the chondrocranium were also compared with those of "mature" chondrocrania of other turtle species in a Principal Component Analysis (PCA). Other than expected, the S. odoratus chondrocranium is not similar in proportions to those of chelydrids, the closest related species in the sample. The results indicate to differences in the proportions among larger turtle clades (e.g., Durocryptodira, Pleurodira, and Trionychia). S. odoratus is an exception to this pattern since it shows elongated nasal capsules similar to the trionychid Pelodiscus sinensis. A second PCA comparing the chondrocranial proportions of multiple developmental "stages" mostly shows differences between trionychids and all other turtles. S. odoratus is again similar to trionychids along PC1, but its proportions are the most similar along PC2 and PC3 to older "stages" of americhelydians, including the chelydrid Chelydra serpentina, which is related to chondrocranium height and quadrate width. We discuss potential ecological correlations of our findings mirrored in late embryonic stages.

Integrating eDNA and citizen science observations to model distribution of a temperate freshwater turtle near its northern range limit.

To determine species distributions and the factors underlying them, reliable occurrence data are crucial. Assembling such data can be challenging for species with cryptic life histories or that occur at low densities. We developed species-specific eDNA protocols, from sampling through data interpretation, to detect the common musk turtle (Sternotherus odoratus) and tested whether eDNA occurrences change our understanding of the species distribution and the factors that shape its northern range limit. We used Species Distribution Models (SDMs) with full parameter optimization on citizen science observations of S. odoratus in Southern Ontario alone and together with eDNA occurrences. Our eDNA protocol was robust and sensitive. SDMs built from traditional observations and those supplemented with eDNA detections were comparable in prediction accuracy. However, models with eDNA detections suggested that the distribution of S. odoratus in Southern Ontario is underestimated, especially near its northern range limit, and that it is shaped by thermal conditions, hydrology, and elevation. Our study underscores the promise of eDNA for surveying cryptic aquatic organisms in undocumented areas, and how such insights can help us to improve our understanding of species distributions.

Metabolic responses to increased temperatures in three semi-aquatic turtle species from the southeastern United States

Physiological maintenance of ectotherms is largely dependent on temperature. Abrupt changes in environmental conditions can cause shifts in energy budgets, with higher temperatures requiring more energy be devoted to maintenance functions, making less energy available for other activities. As a group, freshwater turtles are of conservation concern; thus, it is important to understand their physiological responses to temperature shifts, particularly given current climate change predictions. We quantified metabolic rates (MR) for three species of semi-aquatic turtles that vary in their degree of terrestriality and propensity to aestivate: chicken turtles (Deirochelys reticularia), eastern mud turtles (Kinosternon subrubrum), and eastern musk turtles (Sternotherus odoratus). Metabolic trials were performed using a flow-through respirometer at three environmentally-relevant temperatures: 25 °C, 30 °C, and 35 °C. As expected, MRs of turtles were significantly and positively associated with increases in mass and temperature. Pairwise comparisons revealed that D. reticularia exhibited significantly higher oxygen consumption rates (VO2) relative to K. subrubrum, which had significantly higher VO2 than S. odoratus. The combination of higher metabolic rates, the tendency to terrestrially aestivate, and declining quantity of high quality thermal habitats may place some semi-aquatic turtles at a disadvantage when considering future climate scenarios. Our findings, when combined with knowledge of other ecological traits, may be a useful tool for predicting relative sensitivities of turtle species to predicted climate change, particularly those species inhabiting seasonal wetlands.

Spatial Capture–Recapture Derived Turtle Capture Probabilities and Densities in the Chesapeake and Ohio Canal

More than half of turtle species worldwide are threatened because of habitat loss, invasive species, environmental pollution, disease, unsustainable use, and global climate change. However, some turtles are capable of existing in highly modified habitats, including structures designed to benefit human populations such as reservoirs and canal systems. Examining turtle distributions in large canal systems can inform conservation plans protecting turtle populations within a potential reservoir network and expand our understanding of underlying mechanisms regulating populations. We conducted spatial capture–recapture on turtles inhabiting sections of the Chesapeake and Ohio Canal. We developed a Bayesian spatial capture–recapture model to estimate densities, sex ratios, and associated capture probability parameters for Chrysemys picta (Painted Turtle), Chelydra serpentina (Common Snapping Turtle), Sternotherus odoratus (Eastern Musk Turtle), and Pseudemys rubriventris (Red-Bellied Turtle) captured at 12 sites along 28 km of the canal. We examined the impact of canal depth and forest cover on population densities and the variation in capture probability between sites and sampling days. We found population densities to vary between sites and the associated sex ratios to vary between species, as did the effect of depth and forest cover. Overall capture rates decreased each day, but there was trap-happy behavior from all species except S. odoratus. Our information can set a baseline for understanding turtle populations and inform management in the Chesapeake and Ohio Canal National Historical Park. It is also one of the first studies to establish methods for using new spatial capture–recapture to quantify densities and aquatic space use of turtles.

Hold on for One More Day: Energetic Costs of Oviductal Egg Retention in Eastern Musk Turtles (Sternotherus odoratus).

AbstractIn oviparous reptiles, parental care is often limited to the energy allocated to embryos before oviposition. Reproducing females can allocate energy toward vitellogenesis, determining the number and size of eggs, fertilization, eggshell calcification, retention of eggs within the oviduct after fertilization (oviductal egg retention), and nesting activities. Oviductal egg retention in turtles ranges from 2 wk to half a year, permitting flexibility in the timing of oviposition. The energetic cost of oviductal egg retention in eastern musk turtles (Sternotherus odoratus) was investigated by measuring the metabolism of females before and after oviposition. Gravid female metabolic rates were elevated relative to male and nongravid female metabolic rates, indicating an associated energetic cost for egg retention. Metabolism of gravid females was 40% higher before oviposition than after oviposition, and it was relatively constant across the period of oviductal egg retention. Metabolic costs associated with egg retention were correlated with clutch mass and female body mass but not with clutch size or the number of days leading up to oviposition. These results suggest that the strategy of oviductal egg retention has considerable energetic costs for eastern musk turtles but that it likely provides critical flexibility in nesting phenology.

Learned avoidance of trap locations in freshwater turtles

Context Understanding the effects that learned responses to being captured have on subsequent recapture rates and associated abundance estimates is important for developing accurate descriptions of populations and communities. Although variation in the willingness of individual turtles to be trapped is commonly mentioned in the literature, few studies have experimentally tested learned trap avoidance (or fondness) in turtles. Aims To determine whether turtles learn to avoid traps, whether repositioning traps will lead to increased capture rates, whether this effect varies among species, and whether such relocations yield more accurate depictions of community structure. Methods We studied a community of turtles in a small lake in south-eastern Kansas that included populations of red-eared slider turtles (Trachemys scripta elegans) and common musk turtles (Sternotherus odoratus). We trapped the lake for 35 consecutive days by using two concurrently deployed groups of traps. One group remained stationary for the duration of the study, whereas traps comprising the other group were moved to new locations on Day 14 and returned to their original locations on Day 28, thus dividing the trapping season into three periods. Key results For both species, capture rates declined over time. However, traps in the moved group captured more T. s. elegans than did those in the stationary group during the second period and more S. odoratus during the third period. Traps in the moved group also had higher recapture rates in the second period. Population abundance estimates based on captures from the moved group, the stationary group, and the pool of all captures were similar for T. s. elegans, but for S. odoratus the stationary group of traps produced an abundance estimate much lower than those generated from the moved group and the pool of all captures. Conclusions Both species exhibited learned avoidance of trap locations, but relocating traps had distinct effects on different species, and the accuracy of the observed community structure was improved by relocating traps. Implications The movement patterns and catchability of individuals of different species within a community must be taken into consideration when developing trapping protocols. Even high-intensity trapping over a long period may not generate an accurate sample of the community if different species use the spatial environment in substantially different ways and learn to avoid trap locations.

Rhabdomyosarcoma on the Forelimb of a Common Musk Turtle (Sternotherus odoratus)

Malignant mesenchymal tumours are only rarely reported in turtles. In the present case, an 8-year-old female common musk turtle (Sternotherus odoratus) was presented with a solid, reddened, non-mobile mass on the right forelimb. The mass had a thin, membranous lining and a grey-white cut surface. Histological examination revealed a cell-rich, focally infiltrative neoplasm consisting of spindloid tumour cells arranged in bundles and streams. Rarely, indistinct cytoplasmic cross-striations were seen in the neoplastic cells. Transmission electron microscopy revealed cytoplasmic, disorganized muscle fibrils and haphazardly arranged, attenuated Z-lines in the neoplastic cells. The histological, histochemical and ultrastructural findings led to the diagnosis of a rhabdomyosarcoma. This is the first description of rhabdomyosarcoma in a freshwater turtle.

Short-term impacts of a record-shattering flood and dam removal on a river turtle assemblage and population placed within the context of a 50 year study

Long-term studies are essential for understanding how and to what extent various stressors impact long-lived species, such as turtles. Turtle populations are declining globally. Empirical data from long-term studies of turtles are largely lacking, which hinders the development of effective conservation programs. We evaluated a river turtle assemblage over a 50 year study period (1969–2019), during which the assemblage was impacted by harvesting, habitat degradation, a record-shattering flood, and the removal of a small dam. Our objective was to determine how the turtle assemblage, Graptemys geographica population (i.e., predominant species), and habitat changed in light of a recent record-shattering flood and the removal of a small dam, and place those changes within the context of other stressors documented within the 50 year study period. The record-shattering flood changed the stream and riparian habitat and, along with the dam removal, the turtle assemblage. In the short term, G. geographica and other turtle species within the assemblage, with the exception of Sternotherus odoratus, either exhibited positive or neutral impacts from the flood. We conclude that turtle species adapted to lotic habitats can cope with extreme flooding if their populations are secure prior to flooding and if the riparian and stream habitats are intact. However, as more threats simultaneously impact turtle populations, we expect fewer populations to be able to withstand such additional stressors. Within the context provided by the fifty year study period, we found that harvesting had more immediate negative impacts on the G. geographica population than did flooding.

Ecology of Riverine Turtle Communities in the Southern United States: Food Resource Use and Trophic Niche Dimensions

As part of an integrated study of the ecology of freshwater riverine turtle communities in the southern United States, we analyzed food resource partitioning in the turtle communities of the Cahaba, Chickasawhay, and Pearl rivers. We collected turtles with an array of unbaited fyke nets for periods of 10 d from 1 July to 13 August 1978 and 30 April to 4 August 1979, capturing 2707 turtles of 16 species in 2428 trap days. We successfully flushed the stomach contents from 729 turtles of the following species: Apalone mutica, Apalone spinifera, Graptemys flavimaculata, Graptemys gibbonsi, Graptemys nigrinoda, Graptemys oculifera, Graptemys pearlensis, Graptemys pulchra, Pseudemys concinna, Sternotherus carinatus, Sternotherus peltifer, and Trachemys scripta. We also caught 4 other species in low numbers: Chelydra serpentina, Graptemys pseudogeographica kohnii, Macrochelys temminckii, and Sternotherus odoratus. Stomach contents were identified and quantified by volume and percentage of occurrence for each species from each river. Food items were identified and placed in 6 categories: crustaceans, insects, mollusks, fish, plants, and unidentified. Pseudemys concinna was the most specialized feeder at all 3 sites, feeding almost exclusively on plants, followed by the wide-headed Graptemys and then narrow-headed Graptemys. Specialist species tended to show extensive niche overlap with any other species that consumed a large proportion of the specialists' preferred foods.

Good vibrations: a novel method for sexing turtles

The ability to accurately determine the sex of individuals is important for research and conservation efforts. While most species of turtle exhibit secondary sexual dimorphisms that can be used to reliably infer sex, there are some species that are very difficult to sex, and even within many dimorphic species, it is not uncommon to encounter individuals that appear to exhibit both male and female secondary sex characteristics. Therefore, we tested the novel method of using a vibrator to sex turtles by stimulating male turtles to evert their penises. We tested this method on males of four species (three families) with known sexual dimorphisms: spiny softshell turtles ( Apalone spinifera ; n = 14), western chicken turtles ( Deirochelys reticularia miaria ; n = 17), Mississippi mud turtles ( Kinosternon subrubrum hippocrepis ; n = 10), and common musk turtles ( Sternotherus odoratus ; n = 9). The method accurately sexed 100% of A. spinifera, 64.7% of D. r. miaria , 80.0% of K. s. hippocrepis , and 55.6% of S. odoratus. Despite the low success rates in some species, there are situations in which this method will be useful for researchers working with species that are difficult to sex using external morphological characteristics.

A developmental staging system and musculoskeletal development sequence of the common musk turtle (Sternotherus odoratus)

The extremely derived body plan of turtles has sparked a great interest in studying their developmental biology. Here, we describe the embryonic development of the Stinkpot, or common musk turtle (Sternotherus odoratus), a small aquatic turtle from the family Kinosternidae. We identify 20 distinct developmental stages, some comparable to stages described by previous studies on other turtles and some in between these, improving the resolution of the generalities of turtle development. We provide a detailed account of both the external morphology and skeletal development, as well as a general look at the early stages of muscular development until the attainment of the adult muscular anatomical pattern. Several potential skeletal and muscular apomorphies of turtles are identified or elaborated. The musk turtle, with its small size and hard-shelled egg, could become an important species for the study of turtle evolution and development, suitable for in ovo experimentation and late stage imaging of well-advanced anatomical features.

Potential Environmental Basis for Megacephaly in the Eastern Musk Turtle (Sternotherus odoratus)

Eastern Musk Turtles (Sternotherus odoratus) in a few populations exhibit megacephaly, including those from a population in Arkansas herein described. I initiated a growth experiment in the laboratory with hatchlings from a megacephalic population and those from a nearby normocephalic population in Arkansas, both fed on fish chow for 22 yrs. The experiment, although compromised, suggested that megacephaly in the Eastern Musk Turtle is a plastic, environmental response to diet rather than a genetically based adaptation.

Demographics of Sympatric Musk Turtles: The Loggerhead Musk Turtle (Sternotherus minor) and Eastern Musk Turtle (Sternotherus odoratus) in a Florida Spring Ecosystem

The loggerhead musk turtle (Sternotherus minor) and eastern musk turtle (Sternotherus odoratus) are widespread species considered common throughout much of their respective ranges. Florida populations of S. minor and S. odoratus inhabit a variety of habitats, including freshwater springs and spring runs. We sampled populations of S. minor and S. odoratus from May 2000 through July 2015 as part of a long-term freshwater turtle assemblage study in a state-protected spring-run complex in central Florida. For each species, we 1) generated population estimates, 2) quantified survivorship and recruitment, and 3) calculated sex ratios, biomass, and density. Population estimates were 3417 for S. minor and 1977 for S. odoratus. Sex ratios were approximately 1:1 for both species, and density and biomass estimates were higher than most previous studies. Annual apparent survivorship was higher in male S. minor than in females, but the opposite was true for S. odoratus. Lambda values (k) suggest stable to slowly increasing populations for both species. Population growth rates for S. odoratus were equally influenced by both adult female mortality and mortality of first-year turtles, while those for S. minor were influenced by only adult female mortality. The lower fecundity values for S. odoratus may increase the importance of younger age classes in maintaining populations. Healthy populations of common species are important in maintaining overall community functions, as they often provide the base for many ecosystems. Therefore, it is prudent to promote conservation of common species to protect ecosystem structures and services.

ISOMETRY OF EGG SIZE IN A TEXAS POPULATION OF THE TURTLE STERNOTHERUS ODORATUS THAT EXHIBITS A NEARLY FIXED CLUTCH SIZE

In evaluating optimal egg-size theory and the effects of anatomical constraints on egg size in turtles, pivotal questions concern the significance of the relationship of egg size to female body size and whether the relationship is isometric or hypoallometric. In a central Texas population of the kinosternid turtle Sternotherus odoratus in which clutch size of a sample of turtles was nearly fixed (seven of eight females had two eggs while the largest female had three eggs), there was an isometric increase in egg width with body size among the females with two-egg clutches and significantly reduced egg width in the largest female’s three-egg clutch. Allometric analyses of populations that exhibit little variation in clutch size, as well as analysis of modal clutch sizes in populations with more variable clutch sizes, both have the potential to further illuminate the competing demands of increasing egg size vs. increasing clutch size as females grow larger, enabling them to optimize their reproductive output as it increases with body size.

TURTLE ASSEMBLAGE IN A HIGHLY ALTERED SPRING SYSTEM: COMAL SPRINGS, TEXAS

Comal Springs in New Braunfels, Texas, is the largest freshwater spring west of the Mississippi. The spring is within the Edwards Plateau Savanna Ecoregion of the Southeastern United States Turtle Priority Area. Comal Springs is an environmentally sensitive spring run situated in an urbanized area visited by >1,000,000 people each year and thus may be impacted by recreational use. We assessed baseline population levels for the turtle assemblage residing in Comal Springs. We captured 4,238 turtles from February 2012 to February 2015 across 12 separate sampling sessions. Captures and individually marked turtles (in parentheses) included 2,322 (1,715) Sternotherus odoratus, 1,558 (793) Pseudemys texana, 329 (141) Trachemys scripta, and 29 (19) Chelydra serpentina serpentina. We report population densities of 1,690/ha (S. odoratus), 230/ha (P. texana), 43/ha (T. scripta), and 5/ha (C. s. serpentina). We estimated biomass for each species and sex, resulting in a total biomass estimate of 5,309.6 kg or 632.1 kg/ha. Sex ratios for P. texana and T. scripta were 1:1, whereas the sex ratio for S. odoratus was 2.26:1, male biased. Our results suggest that a robust turtle assemblage inhabits Comal Springs, similar in richness to the more well-studied freshwater spring habitats in Florida. Future studies or management actions can use our data as a benchmark as the results of few turtle surveys in Texas have been published.

A hotspot of xenodiversity: First evidence of an assemblage of non‐native freshwater turtles in a suburban wetland in Central Italy

AbstractThe present study reports on a case of high richness in an assemblage of non‐native freshwater turtles in a suburban wetland of Tyrrhenian Central Italy (Torre Flavia Nature Reserve), providing evidence for first observations of species at regional, national and continental levels. Following a standardized sampling procedure, 54 specimens belonging to seven taxa (ten taxa, including subspecies) were sampled. These includedTrachemys scripta(overwintering in the nest of a juvenile, corroborating its reproduction in the wild),Graptemys pseudogeographica, Pelomedusa olivacea(first observation recorded for Europe), Pseudemys concinna, Pseudemys nelsoni,Mauremys sinensisand an unclassified Kinosternidae (Kinosternon subrubrum subrubrumvelSternotherus odoratus; first observation recorded for Europe at the family level).Due to the high frequency of the most common species (Trachemys scripta: >80% in frequency), this non‐native assemblage was characterized by high Simpson dominance, low Simpson diversity and low evenness values. This appears to be the first evidence of a local hotspot of these non‐native reptiles in Europe. These relevant data and their ecological implications (e.g., alien food webs) are discussed, as well as their conservation concerns and wetland management perspectives.