Evidence: Leopard gecko (Eublepharis macularius) toxicology
Source: Europe PMC (Europe PubMed Central) REST search — first-hand peer-reviewed abstract records, pulled 2026-08-01. Queries covered toxicology, poisoning, intoxication, heavy metals, mycotoxins and (for relevant taxa) envenomation for Eublepharis macularius. The cluster returns 12 representative studies with abstracts below. Abstract text is verbatim from source; each study is traceable by PMID.
Studies
- PMID 41183498 (2026, Genetics) — Candidate genes underlying hypomelanistic morphs in squamate reptiles.. Abstract (opening): Skin coloration is crucial for the survival of animals and ranges from spectacular colorful displays used to attract a mate to cryptic camouflage used to avoid predators. Among the 3 main types of chromatophores, melanophores are the most widespread in vertebrates and can set the skin tone by the amount of melanin they produce and store in dedicated vesicles, the melanosomes. Mutations associated with melanophore differentiation and maturation result in hypomelanistic and amelanistic phenotypes, both extensively studied in mammals but less so in snakes and lizards. Here, we characterize at the genomic, transcriptomic, and histological level, the Hypomelanistic corn snake morph and 3 hypomelanistic leopard gecko morphs. To minimize bias in studying leopard gecko color morphs, we first assembled a chromosome-level genome from a wild-type individual in terms of coloration. We propose that candidate mutations in 3 melanogenesis factors generate these phenotypes: (i) tyrosinase (TYR), an essential enzyme for melanin synthesis, (ii) NCKX5 (SLC24A5), an ion exchanger involved in melanosome maturation, and (iii) the P protein (OCA2), a transmembrane transporter for tyrosine. Our extended bulk RNA sequencing analyses show that additional pigmentation-related genes, affecting melanin production, melanosome motility, and melanophore migration, are dysregulated in the embryonic skin of the mutated animals. This observation highlights the likely associations among the corresponding pathways and is in line with our electron microscopy imaging results. Indeed, the subcellular structure of melanophores is uniquely altered at each of the 4 morphs and likely reflects a multigenic effect. These findings demonstrate that conserved pigmentation genes can produce species-specific effects, underscoring the modular nature of skin coloration in vertebrates. Our work establishes reptiles as comparative models for studying pigment cell biology and reveals evolutionary flexibility in the genetic regulation of melanogenesis.
Source: https://pubmed.ncbi.nlm.nih.gov/41183498/
- PMID 41316997 (2026, Journal of anatomy) — Budding, fission, and fusion: Unveiling patterns shaping pancreatic islet size and distribution in squamate reptiles.. Abstract (opening): A growing body of evidence suggests that lizards are promising model organisms for studying various developmental processes. However, knowledge of pancreatic islet distribution in non-ophidian squamates remains limited. The most comprehensive accounts available to date lack three-dimensional reconstructions and often show inconsistencies. In this study, we aimed to address both aspects: first, by evaluating squamate embryos as model systems for understanding general mechanisms of pancreatic islet morphogenesis in vertebrates, and second, by conducting a comparative analysis of islet development in squamates from an evolutionary perspective. In this study, we analyzed embryos of four non-ophidian squamates representing three major evolutionary lineages: Iguania-the brown anole Anolis sagrei; Gekkota-the leopard gecko Eublepharis macularius and the mourning gecko Lepidodactylus lugubris; and Lacertidae-the sand lizard Lacerta agilis. Three-dimensional reconstructions were created from thick serial sections and high-resolution semithin sections. Pancreatic islet cells in lizards originate from ductal epithelium. Early in development, precursor cells leave the duct walls to form buds that give rise to primary islets, a process evolutionarily conserved across vertebrates. Subsequent growth involves both the fusion of islet buds and the fission of larger agglomerates. Analyzed species differ in islet distribution: The brown anole islet remains restricted to the splenic lobe, whereas the sand lizard, leopard gecko, and mourning gecko also form islets in remaining regions. In studied gekkotans, small- and medium-sized islets tended to be concentrated in close proximity to the spleen. Medium-sized islets dominate the splenic lobe in the sand lizard. Interestingly, we observed a varanid-like condition in the brown anole, characterized by the formation of a single large islet within the splenic lobe, accompanied by a concurrent reduction in islet size throughout the remaining pancreatic regions. This pattern may reflect a broader trend within Toxicofera, a clade identified through molecular studies, toward splenic lobe islet enlargement and a reduction in the size of the islets in the remaining parts of the pancreas. While the phylogenetic position may influence these patterns, our findings suggest that the spatial relationship between the spleen and pancreas, particularly the formation of large islets near the spleen, could play a more direct, possibly inductive, role in islet formation. Further detailed studies, particularly focusing on representatives of Iguania and Anguimorpha, are essential to test this hypothesis.
Source: https://pubmed.ncbi.nlm.nih.gov/41316997/
- PMID 41986369 (2026, NPJ Regenerative medicine) — Heart ventricle regeneration in the lizard Eublepharis macularius, the leopard gecko.. Abstract (opening): Among mammals, injury to the heart typically results in scar formation and diminished cardiovascular function. In contrast, some teleost fish and salamanders can replace damaged heart tissue and restore overall function. For most species, however, less is known. Here, we investigate cardiac self-repair in an amniote capable of multi-tissue regeneration, the leopard gecko (Eublepharis macularius). To create a heart lesion, we placed a liquid nitrogen-cooled metal probe directly onto the ventricle. The result was a cryoinjury to ~20% of the ventricle. Cardiac cryoinjury induced localized cardiac cell death, followed by an increase in cell proliferation by injury-adjacent cardiomyocytes and non-cardiomyocytes. By 100 days, the histology of the ventricular myocardium was nearly completely restored. Echocardiography and invasive hemodynamic monitoring demonstrated that global cardiac function is restored within this timeframe, verifying functional replacement of the myocardium. To explore the molecular basis, we performed bulk RNA sequencing of the injury-adjacent tissue and found that many of the molecular mechanisms common to other cardiac regenerating species, including genes involved in heart development, glycolysis, and extracellular matrix deposition, are also conserved in geckos. Taken together, this work expands the comparative framework of heart regeneration to include reptiles and indicates that the ability to replace missing or damaged cardiomyocytes is shared across >50 million years of evolution.
Source: https://pubmed.ncbi.nlm.nih.gov/41986369/
- PMID 41749246 (2026, BMC veterinary research) — First report of an iridophoroma in a Tegu (Salvator merianae).. Abstract (opening): <h4>Background</h4>This case report describes the clinical and histological findings of a rare periocular iridophoroma in a tegu.<h4>Case presentation</h4>Iridophoroma is a rare type of chromatophoroma, a tumor that arises from iridophores, specialized pigment cells responsible for reflecting light. This case report describes a 6-year-old male Argentine black and white tegu (Salvator merianae) presented with a large, irregular, proliferative mass in the periocular region. The mass originated from the upper left eyelid, partially covering the ocular surface, and measured 2.5 cm in diameter. The patient was referred to the department of Surgery and Intensive care for mass removal and underwent two separate surgical resections. Fine needle aspiration from the structure revealed the diagnosis of iridophoroma, which was later confirmed through histology. This case aims to broaden current knowledge in reptile medicine by presenting an iridophoroma in Salvator merianae, highlighting its clinical presentation, cytological features, and histopathological aspects.<h4>Conclusions</h4>This case represents the first documented occurrence of an iridophoroma in a tegu, highlighting the need for increased awareness and precision in diagnosing tumors in reptiles. The findings demonsrate the importance of paraclinical investigations, such as histopathology, not only in confirming rare conditions but also in differentiating iridophoromas from other potential diagnoses, such as squamous cell carcinoma, papilloma, or melanophoroma. Accurate identification is crucial for guiding appropriate treatment and improving outcomes in reptile medicine.
Source: https://pubmed.ncbi.nlm.nih.gov/41749246/
- PMID 40987466 (2025, Journal of the American Association for Laboratory Animal Science : JAALAS) — Iridophoroma in Leopard Geckos (Eublepharis macularius): Clinical Complications and Histopathology.. Abstract (opening): Leopard geckos (Eublepharis macularius) with lemon frost morphologies are predisposed to iridophoroma, attributed to a tumor suppressor gene mutation also associated with melanoma in humans. In this case series, we describe the clinical presentation, diagnostics, complications, and pathology of iridophoroma in 4 adult leopard geckos, including 2 super lemon frost females and 2 lemon frost males. All animals presented with hyporexia, intermittent lethargy, weight loss, submandibular masses, and oral plaques. In addition, females demonstrated asymmetric coelomic distension, and one male developed altered mentation. Initial differential diagnoses included metabolic disorders, gastrointestinal infectious diseases, and neoplasia. During clinical management of these cases, ultrasonography revealed hyperechoic hepatic nodules in all animals. Fine needle aspiration (FNA) of the subcutaneous submandibular masses found clusters of mesenchymal cells with abundant cytoplasm containing fine birefringent granules. Due to continued decline and poor prognosis, animals were euthanized and submitted for necropsy. Gross examination of all 4 geckos demonstrated skin thickening by white masses throughout the body and multifocal white hepatic plaques. Two females showed yellow, enlarged ovaries, and one of the males had hard intraluminal debris in the urinary bladder. Histopathology of the skin throughout the body showed the dermis and subcutis were infiltrated by myriad pleomorphic, ovoid to fusiform, brown-pigmented neoplastic cells characterized by abundant birefringent intra- and extracellular granules. FNA, ultrasound, necropsy, and histopathology results were consistent with diagnosis of malignant iridophoroma with metastasis to multiple visceral organs including the brain and ovary. In addition, both females developed preovulatory follicular stasis (POFS)-associated oophoritis, and one of the males demonstrated urolithiasis; all of which were considered as metabolic imbalance-related pathology due to hyporexia or tumor invasion. This report illustrates the diagnostic features of FNA, ultrasound, and histopathology of malignant iridophoroma in leopard geckos. It also discusses POFS and urolithiasis as multisystemic sequelae to malignant tumors in geckos.
Source: https://pubmed.ncbi.nlm.nih.gov/40987466/
- PMID 40723477 (2025, Animals : an open access journal from MDPI) — Memory in Leopard Geckos (<i>Eublepharis macularius</i>) in a Morris Water Maze Task.. Abstract (opening): The spatial orientation of mammals and birds has been intensively studied for many years, but the cognitive mechanism of spatial orientation and memory used by squamates remains poorly understood. Our study evaluated the learning and memory abilities of leopard geckos (<i>Eublepharis macularius</i>) in an adapted Morris water maze. The animals learned during the training phase consisted of 20 trials. To assess long-term memory, we retested geckos twice after several months. The geckos remembered the learned information in a short re-test after two months, but after four months, they required retraining to find the platform. We hypothesise that the duration of memory corresponds with short-term changes in semi-desert environments within one season, while disruption of memory performance after a six-month gap may simulate the more extensive seasonal change in spatial relationships in their natural environment. Moreover, during the winter period, geckos exhibit low activity, which can be connected with decreased frequency of foraging trips. Therefore, the memory loss after four months may reflect the low level of memory jogging. The motivation during the experiment was the crucial parameter of learning and memory processes. In later phases, geckos were less motivated to perform the task. Finally, they relearned the spatial orientation task, but they moved more slowly as the experiment progressed.
Source: https://pubmed.ncbi.nlm.nih.gov/40723477/
- PMID 41102773 (2025, BMC veterinary research) — Gastrointestinal apicomplexan parasites of captive reptiles: diversity, causes, consequences.. Abstract (opening): <h4>Background</h4>Captive reptiles frequently suffer from gastrointestinal parasites, which stem from their breeding conditions such as limited space and frequent contact with faeces, high numbers of individuals in inadequate conditions, stress, but also from extensive exports and imports in recent years. In particular, parasites with single-host life cycles are common as they can easily complete their development. This study focused on extensive sampling across a variety of captive reptiles groups including lizards (agamas, chameleons, geckos, iguanas, monitors, skinks), snakes, tortoises, and also crocodiles, originating from various resources (pet trades, private breeders, and zoos).<h4>Results</h4>Examination of faecal samples revealed that 17.9% (55/308) of captive reptiles were infected with coccidia, namely Eimeria (7.1%), Choleoeimeria (5.5%), Isospora (3.9%), and Caryospora (0.3%), and that 3.2% (10/308) were infected with Cryptosporidium. These apicomplexans, which have monoxenous life cycles, may easily be maintained in breedings, and commonly transmitted to the breedings of new owners via trades and expos. While Choleoeimeria spp. were most prevalent in snake hosts, Isospora amphiboluri was recorded as the most common parasite of bearded dragons; however, its host specificity was shown to be relatively low, as it was also able to infect veiled chameleons. In addition, other representatives of coccidia, as well as pseudoparasites from prey items, were also recorded. Although the treatment of coccidiosis in reptiles remains debatable, our findings revealed that it was more effective to treat infected animals with anticoccidials than to leave them untreated.<h4>Conclusions</h4>This is a comprehensive study on a variety of genera of gastrointestinal apicomplexan protists in captive reptiles that considers not only their detection and identification based on a robust combination of morphological and molecular data, but also their host specificity, evolutionary relationships, clinical status, and possible pseudoinfections with parasites of prey items that cannot be proven without the use of molecular methods. The study highlights the frequent occurrence and importance of gastrointestinal parasites in the health of captive reptiles, the need for their examination and consideration, and the application of proper management strategies.
Source: https://pubmed.ncbi.nlm.nih.gov/41102773/
- PMID 41600686 (2025, Veterinary sciences) — Biochemical and Hepatic Determinants of Reproductive Failure in Reptiles: A Review of Dystocia Pathophysiology and Management.. Abstract (opening): Dystocia represents a multifactorial and clinically significant reproductive disorder affecting a broad spectrum of reptilian species. Commonly resulting from prolonged vitellogenesis, endocrine disruption, or hepatic lipidosis, dystocia is often exacerbated by suboptimal husbandry or concurrent disease. This review critically evaluates the etiology, diagnostic criteria, and therapeutic interventions associated with this condition. Emphasis is placed on the interplay between metabolic exhaustion and hepatic compromise, which may lower the threshold for surgical intervention. The efficacy and limitations of oxytocin-based protocols are discussed in the context of hormonal receptor variability and response attenuation. Advanced diagnostic modalities, including ultrasonography, radiography/CT, and biochemical profiling, are reviewed for their utility in case stratification. Finally, surgical management options are considered for cases refractory to medical treatment, with attention paid to timing, anesthetic risk, and post-operative care. Collectively, this synthesis aims to inform evidence-based clinical decision-making and promote improved standards of care in reptile reproductive medicine.
Source: https://pubmed.ncbi.nlm.nih.gov/41600686/
- PMID 40747269 (2025, Frontiers in neuroanatomy) — The relative withdrawal of GFAP-An essential component of brain evolution.. Abstract (opening): The glial fibrillary acidic protein (GFAP) is the principal intermediate filament protein and histochemical marker for astroglia. It appears contradictory that there are extended GFAP-poor or even GFAP-free areas in the brains of various vertebrate clades: cartilaginous and ray-finned fishes, and amniotes. The "Relevant Subsections: Extended GFAP-free areas in various vertebrates" section in this study reviews our GFAP mapping studies on the brains of 58 species within these clades, as well as mappings from other authors, and demonstrates that these areas appeared independently from one another in the more advanced groups of different clades; it raises the supposition that the lack of GFAP is an apomorphic phenomenon. The GFAP expression has withdrawn mainly relatively: the GFAP-immunonegative areas increased more than the immunopositive ones. Primarily, regions that expanded and increased in complexity during evolution lack GFAP immunopositivity (except for their perivascular glia). The absence of GFAP expression, however, does not indicate the lack of astroglia. In the areas immunonegative to GFAP, astrocytes were visualized using other markers, such as glutamine synthetase or S-100 protein. In birds and mammals, lesions induced GFAP expression in these areas. It shows that the ability to express GFAP is not lost but has become facultative. These data suggest that the lack of GFAP production may provide an evolutionary advantage. The "Discussion" section relates the GFAP "withdrawal" to other steps of evolution: the increasing complexity and thickening of the brain wall, as well as the appearance of the astrocytes, particularly protoplasmic astrocytes, and then examines the proposed evolutionary advantages and disadvantages of the absence of GFAP. The role of the relative "withdrawal" of GFAP expression in brain evolution remains to be definitively answered. The most probable candidates may include the absence of synthesizing an unnecessary protein, improved adaptation of astrocytes to the demands of neurons, and an increased capacity for synaptic plasticity. In contrast, one must consider that the withdrawal of GFAP may not be a primary phenomenon but rather a consequence of the evolution of neural networks.
Source: https://pubmed.ncbi.nlm.nih.gov/40747269/
- PMID 40818077 (2025, Veterinary radiology & ultrasound : the official journal of the American College of Veterinary Radiology and the International Veterinary Radiology Association) — Comparative Sonographic Studies of the Urogenital Tract in Lizards.. Abstract (opening): The assessment of the urogenital tract is of great importance in the diagnosis of diseases in lizards, and sonographic examination is the most suitable imaging method for this purpose. However, reference data are not available for most of the commonly kept species. The objective of this prospective anatomical analytical study was to sonographically examine the urogenital tract of four of the most commonly kept lizard species and compare their kidneys, testes, and ovaries. A total of 41 lizards, 14 bearded dragons (Pogona vitticeps), 15 leopard geckos (Eublepharis macularius), seven veiled chameleons (Chamaeleo calyptratus), and five panther chameleons (Furcifer pardalis) were included. An 8-18 MHz field hockey stick transducer and a 6-15 MHz linear transducer were used. Sagittal and transverse images of the organs were recorded. The kidneys could be visualized and assessed in full length in all lizards, the testes in 18 of 19, and the ovaries in 13 of 22 lizards. The results of the current study could serve as reference values for future studies on the species mentioned.
Source: https://pubmed.ncbi.nlm.nih.gov/40818077/
- PMID 40088131 (2025, Developmental dynamics : an official publication of the American Association of Anatomists) — Squamate ventricular cardiomyocytes: Ploidy, proliferation, and heart muscle cell size in the leopard gecko (Eublepharis macularius).. Abstract (opening): <h4>Background</h4>While heart function is broadly conserved across vertebrates, the cellular phenotype of muscle cells (cardiomyocytes) varies across taxa and throughout ontogeny. Emerging evidence suggests that some attributes may correlate with the capacity for spontaneous cardiomyocyte replacement following injury. For example, among non-regenerating taxa like adult mammals and birds, cardiomyocytes are polyploid, rarely proliferate, and are large in size. In contrast, in regeneration-competent zebrafish and amphibians, cardiomyocytes are diploid, spontaneously proliferate, and are comparatively small. For other species, less is known.<h4>Results</h4>Here, we investigate these attributes in the squamate Eublepharis macularius, the leopard gecko. Using the nuclear counterstain DAPI to measure fluorescence intensity as a proxy for DNA content, we found that >90% of adult cardiomyocytes are diploid. Using serial histology and immunostaining for markers of DNA synthesis and mitosis, we determined that adult gecko cardiomyocytes spontaneously proliferate, albeit at significantly lower levels than previously reported in subadults. Furthermore, using wheat germ agglutinin, we found that the cross-sectional area is maintained across ontogeny and that gecko cardiomyocytes are 10× smaller than those of mice.<h4>Conclusions</h4>Taken together, our data show that gecko cardiomyocytes share several key cellular attributes with regeneration-competent species and that postnatal ventricular growth occurs via cardiomyocyte hyperplasia.
Source: https://pubmed.ncbi.nlm.nih.gov/40088131/
- PMID 41150105 (2025, Veterinary sciences) — Measuring the Rise and Fall of Plasma 25-Hydroxyvitamin D Concentrations in Blue-Tongued Skinks (<i>Tiliqua scincoides</i>) Following Ultraviolet B Exposure and Withdrawal.. Abstract (opening): Species-specific husbandry guidelines remain limited for blue-tongued skinks (<i>Tiliqua scincoides</i>), especially in relation to ultraviolet B (UVB) lighting and vitamin D requirements. This study aimed to determine whether UVB exposure is necessary for these skinks and how long 25-hydroxyvitamin D (25-OHD) concentrations persist after UVB withdrawal. Eleven adult skinks who had been fed with wet cat food were exposed to 12 or 2 h of UVB per day for four weeks. Plasma 25-OHD concentrations were very low at the baseline, and significantly increased post-UVB in both groups (<i>p</i> < 0.01), with the 12-hour group increasing from baseline concentrations of 18.5 [12.8-20.5] nmol/L to 820 [730-1251.3] nmol/L and the 2-hour group increasing from baseline concentrations of 22 [15.5-22] nmol/L to 635 [401-892.5] nmol/L. Following the discontinuation of UVB exposure, 25-OHD gradually declined and was not significantly different from baseline concentrations at 7 and 4 months for the 12-hour and 2-hour groups, respectively. Dietary vitamin D<sub>3</sub> (2.5 IU/g as dry matter basis), provided through wet cat food alone, appeared insufficient to support sustained plasma 25-OHD concentrations. These findings strongly suggest that blue-tongued skinks rely on UVB exposure to increase their 25-OHD concentrations. Moreover, the shorter 2-hour exposure provided a significant rise in 25-OHD concentrations and remained above baseline for 4 months, suggesting the shorter exposure can benefit these animals, while potentially reducing secondary risks associated with UVB exposure.
Source: https://pubmed.ncbi.nlm.nih.gov/41150105/
Source text: pdf-raw/evidence/europepmc_leopard_gecko_toxicology_2026-08-01.txt (Europe PMC first-hand abstracts, pulled 2026-08-01).