pp. 350-351

Obituary - Keith Corbett MBE - by Howard Inns

pp. 341-349

Authors: Swarup Ranjan Mohanty, Soumya Sephalika Swain, Bhabani Sankar Mohapatra, Sudeep Kumar Behera, Shubhransu Nayak & Satyaranjan Behera

Abstract: Chelonians belong to the class Reptilia and include turtles, tortoises and terrapins which primarily inhabit freshwater, brackish, coastal and terrestrial ecosystems. More than 50% of the 364 known living species of turtles and tortoises are under the Threatened category which are facing a perilous situation. They encounter various pathogenic and non-pathogenic bacteria and fungi in the sand and soil of nesting habitats while laying their eggs. In comparison to the non-nesting beaches, sea turtle nesting beaches possess significantly higher nutrient loads and microbial abundance. This higher microbial load is becoming an imperceptible threat to the survival rate of sea turtle embryos on the nesting beaches. However, like other reptiles and faunal groups, turtles also secrete cloacal fluids or oviductal fluids while laying eggs which possess antimicrobial properties to various pathogenic bacteria and fungi. The cloacal fluid contains both simple glycoproteins and Antimicrobial Peptides (AMPs), which play a role in antimicrobial defense. AMPs have been isolated from other fauna where a good number of research has been carried out on protein molecular biology for their application in the pharma industry for therapeutic uses. Though sporadic and preliminary investigations have been carried out on the antimicrobial nature of cloacal fluids, no in-depth insight is available regarding their mechanism of action, the biochemical and molecular engineering of these simple glycoproteins, and their potential pharmaceutical applications. Further, the studies have been mostly restricted to a few species and few provinces only. Hence, lots of research gaps need to be addressed on this aspect of turtle conservation. The Convention on Biological Diversity envisaged International Governments to conserve biodiversity with people’s participation along with the flow of benefit sharing to the conserver of bioresources. The current review was carried out to bring insight into the antimicrobial nature of cloacal-oviductal fluids and their potential for chelonian conservation.

Keywords: cloacal-oviductal fluid, antimicrobial peptide, turtle, chelonian, pathogen

pp. 333-340

Authors: Dylan Koalani Highland & Edward A. Myers

Abstract: Molecular species delimitation can clarify species limits and uncover morphologically cryptic taxa, particularly in groups that have conflicting taxonomies based on morphology alone. We reassess the phylogenetic relationships within Echis, a viperid genus widely distributed in the Eastern Hemisphere with a complicated taxonomic history. Using 134 mitochondrial cytb sequences sampled from ten of the twelve currently recognised species, we applied gene-tree and distance-based species delimitation methods to delineate evolutionary significant units within Echis. Our results validate current taxa, adding additional support to recently described species, and uncover cryptic genetic diversity within Echis. Although single-locus delimitation methods may not fully capture species diversity, congruent support between methods can identify lineages in need of future investigation. We emphasise that the lineages identified here can be used as a guide for further geographic sampling and in an integrative taxonomic treatment of Echis that combines genomics, morphometrics and ecological data in a unified framework.

Keywords: diversification, phylogenetics, population genetics, species delimitation, Viperinae

pp. 323-332

Authors: Riccardo G. Mattea, Dillon Jones, Steven J.R. Allain, Alexis M. Barahona-Velastegui & Mika Peck

Abstract: Reserva Tesoro Escondido is located within the Tumbes-Chocó-Magdalena biodiversity hotspot in north-west Ecuador and is home to approximately 679 amphibian species. This study aimed to investigate the effects of disturbance on amphibian species richness, abundance and assemblage through the use of visual encounter surveys along three study sites within the Reserva Tesoro Escondido. The results from these surveys report 406 observations and 46% of the total known amphibian species. Species evenness and diversity did not significantly vary across three sites sampled in the reserve even when accounting for abiotic factors, resulting in a site-specific species assemblage. Generalised Linear Models (GLM) investigated species richness and abundance relationship to environmental variables, finding altitude as the most significant factor on species abundance and richness. Overall, the results showed great diversity and no trace of species homogenisation across habitats which may be linked to disturbance.

Keywords: Amphibians, species richness, disturbance ecology, Ecuador biodiversity, Chocó

pp. 312-322

Authors: Patricia Marques do A. Oliveira, Carlos A. Navas & Pedro M. Sales Nunes

Abstract: Semi-arid environments impose significant thermal stress on ectotherms, requiring specialised water acquisition strategies. This study investigated the water status of three lizard species from the Caatinga, examining the interaction between environmental factors and physiological adaptations for water acquisition. To achieve this, we combined field data—including body mass, body condition and body temperature—with induced hydration experiments to quantify water uptake. Additionally, environmental factors such as soil and air temperature, as well as humidity, were measured. Ameivula ocellifera exhibited the highest water absorption, potentially reflecting greater dehydration due to its active foraging and sun exposure. Conversely, Tropidurus semitaeniatus absorbed less water, suggesting better hydration, possibly linked to its rocky habitat that may enhance water retention. Soil temperature and humidity significantly influenced the water status of all species, underscoring the role of ectothermy in water regulation. These findings highlight the importance of ecological context and environmental conditions in shaping water-related adaptations in semi-arid lizards.

Keywords: reptiles, brazilian drylands, experimental hydration, body weight

pp. 308-311

Authors: Calvo Rodrigo, Velasco Melina Alicia, Rolón Melisa Celia Jazmin, Martinez Aguirre Tomás, Igor Berkunsky & Kacoliris Federico Pablo

Abstract: This study represents the first application of radio telemetry on the Critically Endangered Valcheta frog Pleurodema somuncurense from Argentina’s Patagonia, aimed at understanding its spatial ecology, daily movements and home range. Six adult individuals were equipped with radio transmitters to assess their activity patterns and habitat use. Average travel distances from sunset to night detection and from sunset to sunrise were 6.47 m (± 4.2) and 6.32 m (± 4.87), respectively, with no significant difference (Student’s t-test, p = 0.42, α = 0.05). Over a complete activity cycle, individuals moved an average of 8.62 metres (SD = 2.2). The estimated home range was 39 m² including an individual with heightened movement, and 30 m² excluding it. Movements ≤ 5 m were categorised as local adjustments, while > 5 m were exploratory migrations, the latter comprising 25.54% of movements in most individuals, though one frog exhibited 56.25%. Despite successful data collection, high mortality and transmitter displacement highlight the technique’s limitations in aquatic anurans. Findings from this study provide valuable data on P. somuncurense’s habitat connectivity needs, informing restoration and conservation efforts across its restricted range. Future studies should consider adjusting the telemetry approach to mitigate the impact on behaviour and survival.

Keywords: connectivity, Somuncura plateau, transmitter, amphibian conservation

pp. 303-307

Authors: Mitsuki Takano & Takashi Haramura

Abstract: Hynobius retardatus is a salamander distributed in Hokkaido, Japan which is a subarctic region, and populations breed in both urban and coastal areas. To understand why some populations of this species can breed in coastal areas, we tested the salinity tolerance of H. retardatus eggs collected from both coastal and urban areas. At 0 ppt salinity (control), over 95% of eggs hatched normally in both coastal and urban populations. However, survival rate of eggs was significantly different among populations in 4 ppt and 5 ppt salinity. No eggs hatched over 10 ppt salinity in all populations. Deformation rate was also increased with salinity level, and differed among populations. Our results showed that eggs from coastal populations had higher survival in high salinity compared to eggs from urban populations.

Keywords: salinity tolerance, egg mortality, deformation rate, coastal area, intraspecific variation

pp. 299-302

Authors: Mickaël Sanchez, Alicia Bonanno, Margot Caubit & Johanna Clémencet

Abstract: The Manapany day gecko Phelsuma inexpectata is endemic to Réunion Island and listed as a Critically Endangered species. Despite high conservation stakes, basic morphological data are scarce. Based on 389 captures across its geographic range, we provide the first large data set on body size allowing estimation of size at sexual maturity. Based on the snout-vent length (SVL) distribution of mature males and females, the transition size between the immature stage and the mature stage is estimated at a minimum of 42 mm SVL. Unambiguous indicators of sexual maturity are observed at a minimum SVL of 42 mm in males and 47 mm in females. Males are significantly larger than females, and both can reach a larger size than previously described in the literature. Finally, based on the temporal distribution of gravid females, we show that the egg production period may begin earlier than previously described in the literature.

Keywords: Manapany day gecko, morphology, reproduction, Réunion Island

pp. 287-298

Authors: Thomas W. Fieldsend, Herbert Rösler, Kenneth L. Krysko, Madison E.A. Harman, Stephen Mahony & Timothy M. Collins

Abstract: The red-spotted tokay gecko Gekko gecko (Linnaeus, 1758) is a widely distributed Asian gecko that has established outside of its native range in southern Florida, USA. This study used genotypic and phenotypic data to determine whether multiple, distinct forms of red-spotted tokay gecko are present in southern Florida, as has previously been hypothesised. Analysis of mitochondrial (ND2) and nuclear (RAG-1) sequence data identified two discrete mito-nuclear lineages in southern Florida, and population-level morphological structure was non-randomly associated with mito-nuclear lineage, confirming a weak but significant genotype-phenotype link. Multiple lines of evidence thus indicate the introduction of two distinct forms of tokay gecko to southern Florida.

Keywords: biological invasions, multiple introductions, taxonomy, tokay gecko

pp. 278-286

Authors: André Kaufer Leite, Jaqueline Bianque de Oliveira, Moacir Santos Tinôco, Tércio da Silva Melo & Geraldo Jorge Barbosa de Moura

Abstract: Studying the ecological and evolutionary relations between parasites and their hosts is relevant for understanding the biology and conservation of hosts, as it helps to determine which factors influence parasitism, whether intrinsic (sex, age, morphology) or extrinsic (environmental). Glaucomastix abaetensis is an endemic lizard found in the restingas along the northern coast of the state of Bahia, in the north-eastern region of Brazil, and is classified as Endangered. The aim of the present study was to determine the parameters of the parasite ecology of populations of G. abaetensis in two areas with restinga vegetation. Of the 166 individuals studied, 25.3% harboured parasites, with an average infection intensity of 3.63 ± 0.84 (ranging from 1 to 7.6). The results obtained for this species had not been previously documented and may contribute to conservation plans for the species and the ecosystem in which they live, as information on the parasite-host relationship is essential for understanding the interactions of this species within the environment.

Keywords: reptiles, hosts, endoparasites, parasite infection, conservation

pp. 266-277

Authors: Giulia Simbula, Gianpaolo Montinaro, Tina Grimm & Jan-Dieter Ludwigs

Abstract: Radiotelemetry has emerged as a crucial tool in wildlife biology, enabling researchers to monitor animal movements and behaviours in their natural habitats. While extensively used across various taxa, there remains a scarcity of studies dedicated to optimising radiotelemetry techniques for reptiles, especially small–medium lizard species (50–400 mm total length). In this study, the efficacy of two radio transmitters (Lotek PIP5 and Telemetrie-Service Dessau models) and different attachment methods on sand lizards inhabiting vineyard ecosystems were investigated. We evaluated three harness designs adopted over two years of fieldwork, the Adapted Rappole-Harness (ARH), Shoulder Harness (SH), and Axillary Harness (AH), considering methodological details, attachment longevity, signal range and strength, potential behavioural effects, threats to lizards’ health and survival. Our results indicated that the ARH model was unsuitable, as lizards quickly removed it after few minutes. The SH remained attached for a maximum of 10 days, while the AH lasted up to 17 days, withstanding adverse environmental conditions and terrain abrasion. This study provides valuable insights into optimising radiotelemetry techniques for small–medium reptile species. By considering harness design, attachment location, materials and transmitter shape, researchers can enhance the welfare of tagged individuals and improve the efficiency of telemetry studies. Furthermore, this research underscores the need for standardised guidelines for transmitter attachment in reptiles, promoting animal welfare and advancing scientific understanding in this field. Sharing experiences and collaborating within the scientific community will foster progress in developing effective and ethical transmitter attachment protocols for small–medium reptiles.

Keywords: harness designs, radio-tag, sand lizards, telemetry, transmitters devices

pp. 260-265

Authors: Pearson McGovern, Edem Eniang, Stephanie N. Ajong, Gift Simon Demaya, Mathias Behangana, Sery Gonedele-Bi, Fabio Petrozzi, Godfrey C. Akani, Julia E. Fa & Luca Luiselli

Abstract: How species interact with their environments is critical to ensuring proper conservation action. Interactions come in many forms, but one of the most basic and least studied for tropical freshwater chelonians seems to be their diet, a proxy for determining generalist versus specialist species. Even less represented in the scientific literature on chelonians are studies of intraspecific variation in diet, specifically dietary differences between the sexes and ontogenetic shifts in diet for large-bodied species. Herein, we investigate the diets of male, female and juvenile (< 25 cm SLC) Trionyx triunguis in both their east and west African range to evaluate differences and measure their dietary generalism. We found ontogenetic and location-based dietary differences.

Keywords: geographical comparison, omnivory, ontogeny, softshell, turtles

pp. 251-259

Authors: Ling Li, Gang Wang, Songwen Tan, Peng Guo, Bingjun Dong & Yayong Wu

Lizards exhibit sexual dimorphism in various phenotypic traits and whole-organism performance (e.g. bite force). The patterns of sexual dimorphism vary among genera and species. The relationship between morphology and function is dynamic, and selective pressures can differentially affect bite performance in different sexes. Here, we analysed sexual dimorphism in morphological traits and bite force, and explored the determinants of bite force between two sexes in the mountain dragon Diploderma batangense from western China. A total of 135 individuals were collected and seven morphological characteristics and bite force were measured. We found a significant male bias in morphology and bite force performance, with males exhibiting larger head size, body size and bite force than females, which may be explained by sexual selection. Results also showed that bite force was positively correlated with head size, with the determinant affecting bite force differing between males (mouth length) and females (head width), which may be related to their different roles in reproduction. This study provides a reference for understanding the ecological adaptability of mountain dragons in the field and lays a foundation for revealing the mechanism of bite force variation between the sexes.

Keywords: bite force, lizards, sexual dimorphism, morphology, sexual selection