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Animal coloration is often shaped by a myriad of factors that lead to differences in colour through changes in the chromatophores. Depending on how this variation is partitioned, coloration is often categorized as continuous or polymorphic. However, the boundaries between these two categories are not always clear. Here, we investigated whether the ventral coloration of the Madeiran wall lizard (Teira dugesii) varies continu- ously or corresponds to discrete colour morphs, via by-eye colour classification and visual modelling. By combining these two approaches, we show that T. dugesii coloration varies continuously and that colour classifications based on anthropomorphic approaches alone are ill suited to describe animal coloration. We also tested the influence of size, body condition, and sex as possible factors that might explain differences in T. dugesii coloration. We found that body condition, and especially size and sex, explain a great proportion of the variability observed in this spe- cies. These differences point to an effect of ontogeny, which might play a major role in colour development owing to the longevity of this species. Moreover, the sexual dichromatism that this species shows is indicative of an effect of sexual selection on coloration, perhaps explained by dif- ferences in circulating hormones.

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The research on animal colouration has always been of great interest for biologists but since the last decades it has grown exponentially thanks to multidisciplinary approaches. Animals have found several ways to deal with the camouflage/com- munication trade-off in colouration, leading to the evolution of alternative patterns of variation of colourations at different levels including signal partitioning and spatial resolution of colouration. In this paper we analyse the variability of dorsal and ventral colouration in males and females of Maltese wall lizards in three populations on Linosa. We collected high- resolution digital images of dorsal, ventral and throat colouration from 61 lizards (32 males and 29 females). We showed that the colouration differs among sexes and body regions within the same individual. Colourations are also variable among individuals within population, as well as among different populations across the Island. Finally, we detected a lizard’s col- ouration shifts with increasing body size. Those result supports the hypothesis that colouration in this species evolved under the competing pressures of natural and sexual selection to promote signals that are visible to conspecifics while being less perceptible to avian predators.

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Giovanni Gulia was a prominent Maltese naturalist. According to Schembri (2003) `In 1913, Giovanni Gulia, one of the foremost Maltese naturalists of that period, attended the Ninth International Zoological Congress held in Monaco and read a paper titled `Uno sguardo alla zoologia delle Isole Maltesi` (Gulia, 1914). This was a review of zoological research on the islands carried out to that date, treating both the marine and the non-marine fauna, and it summarised much of the earlier literature as well as gave additional unpublished information.` Schembri, P.J. (2003) Current state of knowledge of the Maltese non-marine fauna. In: Malta Environment and Planning Authority Annual report and accounts 2003. pp. 33-65; Floriana, Malta: Malta Environment and Planning Authority, 92 pp.

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On a herpetological trip to the north-west of the Iberian Peninsula, the authors were able to record a total of ten species of lacertid lizards along with other reptile species. In particular, the densely populated Portuguese Atlantic coast proved to be a species-rich lizard habitat.

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In early June 2024, heavy rainfall events led to the flooding of a meadow habitat in Bavaria, which is inhabited by several reptile species. The article describes observations on the reptiles’ reactions to the flooding. Apparently, the two lizard species present, Lacerta agilis and Zootoca vivipara, coped better with the temporary flooding than the slow worms (Anguis fragilis) that also occur there. The two snake species present in the habitat, Natrix natrix and Vipera berus, on the other hand, were not sighted during the flooding.

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The discovery of a common wall lizard (Podarcis muralis) in the Bergisches Land (North Rhine-Westfalia) outside the species’ known distribution range is reported. The trade in flowers, perennials, and landscaping material is suspected as a possible cause of the dispersal, as there is a large garden center in the vicinity.

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In the course of multi-year field research (2002–2022, and partially 2023) in the Ka- radag Nature Reserve (southeastern Crimea; 44.9o N, 35.2o E) the seasonal activity frame and terms of the emergence of juveniles were studied in two common species of lacertids: the Bal- kan wall lizard (Podarcis tauricus) and the Crimean rock lizard (Darevskia lindholmi). Activity during the winter period is characteristic for both species: over 22 years of observations, P. tau- ricus and D. lindholmi were observed in the winter months during 20 and 16 seasons, respec- tively. In P. tauricus the average for all years dates of the first and last observations of active individuals are February 13 and December 4; those in D. lindholmi are February 18 and No- vember 26. The length of the activity period, determined by the dates of the first and last rec- ords, in P. tauricus is 65–91% of the total duration of the year, and in D. lindholmi is 62–89% of the year. The duration of the period of full activity (from the beginning of the species’ regu- lar activity to the hibernation) is 236–321 days (273 days on average) in P. tauricus, and 227– 302 days (260 days on average) in D. lindholmi. Egg-laying in P. tauricus occurs mainly in May–July (two clutches per season), while in D. lindholmi it occurs in July, but may continue into August (usually the only clutch per year). Therefore, the average for all years dates of the first registration of hatchlings differ by approximately seven weeks: July 12 in P. tauricus, Au- gust 29 in D. lindholmi. The timing of the emergence of yearlings of both species is positively correlated at a statistically significant level. In both species, a statistically significant correlation with the climatic characteristics of the area of study was found for a number of phenological phenomena. In many cases, the relationship between the phases of the lizards` life cycle and climatic parameters at the trend level was confirmed.

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We used the route method to carry out quantitative counts of reptiles in nine regions of Southeastern Kazakhstan. The results yielded data on the population density of reptiles in fourteen habitats. We observed the greatest diversity of species and the largest number of rep- tiles in sandy deserts. Both measures were much smaller in loamy plains and low mountains. In desert habitats, the Central Asian tortoise Agrionemys horsfieldii and the rapid racerunner Ere- mias velox were more common than other species. In the desert habitat, agama Trapelus san- guinolentus was less common. Despite its wide distribution, the Central Asian tortoise was rare or common in most habitats: its population density values did not exceed four individuals/ha. High numbers (23.2±8.4 ind./ha) were recorded for the species only in the north of the Moyin- kum desert. The population density of the tortoise in commercial harvesting areas from 1950 up to the 1980s remained low (3.5±0.9 ind./ha) and failed to recover. Using the population density data, we calculated similarity indices of reptile communities and then grouped communities in- to several complexes based on similarity indices and the ecological specialization of numerical- ly dominant species. In loamy, sandy loam, and stony deserts, eurytopic species formed the ba- sis of the population. These were A. horsfieldii, E. velox, and T. sanguinolentus. In the sands of Taukum and Saryesik Atyrau, racerunners (Eremias) dominated in the reptile communities. These were E. intermedia, E. lineolata, and E. velox, among these stenotopic species dominated. The community of the foothills of the Kyrgyz ridge turned out to be the most isolated from the others. The similarity was revealed between nine desert areas in terms of reptile fauna. The de- serts that are similar in landscape features (especially the substrate and vegetation) had high in- dices of commonality regardless of their remoteness and isolation. This shows that the process of historical dispersal of species and their movement between territories faced no obstacles.

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The article is based on materials on age-related changes in the color of the lower sur- face of the tail and back of the thighs in the population of the Rapid racerunner (Eremias velox velox Pallas, 1771), living on the Sarykum sandy massif. The material was collected in the first ten days of May 2023. A total of 110 individuals were caught and described: 44 males, 36 fe- males and 30 immature individuals. The size characteristics of sex and age groups are given. It is known that in immature individuals the lower surface of the tail and the back of the thighs are blood-red to orange in color, while in adult animals the entire lower surface of the body and tail is white. The research materials clarify the course of these age-related changes. In Sarykum males, the change from juvenile to adult coloration occurs with the onset of sexual maturity. In females, this process is extended and most lizards across a wide range of sizes retain the colora- tion of the young, with some lightening options. In immature individuals, the coloration in the orange-red range is characteristic of all animals, but in 16.7% of lizards the process of its light- ening begins. It can be assumed that the latter will turn out to be males in the future. For the de- scription, the RGB color code table is used according to two color codes: HTML/CSS color name and decimal code (RGB).

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Main observations were made in a sample plot (by 10 km2) during 1999–2023. In 1999 about 40% of the sample plot was arable lands. In 2000–2003 the ploughing had been stopped. In sandy patches, former arables began to be replaced by heathlands with xerophytic grass and sparse sprouts of pine. In 1999–2005 Z. vivipara inhabited the outer edges of flood- plain forest with high density; L. agilis distribution was restricted to small patch (about 25 ha) of drained peatland located 4 km away from floodplain forest. Since 2006 L. agilis began to in- habit arising heathlands, and by 2019 its population has reached high density there. Z. vivipara was pushed out of the forest edges into the floodplain. In 2000–2023, the duration of period with favorable for lizards activity temperature conditions was for 15–17 days longer than in 1978–1999. There is a desire to suggest that spatial redistribution of lizards is dependent on temperature conditions. However, comparison of lizard’s distribution in sample plot with the same in adjacent areas, where agricultural lands were absent and heathlands were widely repre- sented, indicates that main factors of lizard’s habitat re-distribution are a decrease of anthropo- genic pressure, natural succession of vegetation communities and interspecific competition in the lizards. Climate change could be the cause of increase in the growth rate of population on newly settled areas, but it not be a trigger of a spread.

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The study of genome size variation in cells of vertebrates using the DNA flow cytometry makes it possible to precisely determine polyploid individuals, which is extremely important when studying the processes of reticulate speciation. In addition, in many groups of vertebrates, closely related species often differ in the nuclear DNA content. Therefore, the purpose of our study was to explore the variability of genome size and ploidy in populations of 29 species and subspecies of mountain lizards of the genus Darevskia, as well as their hybrids. As a result of the study, the range of variability in individuals of different ploidy (91% of diploid and 9% of triploid individuals) was established not to overlap. Among diploid species, no correlation was found between the nuclear DNA content and phylogenetic relationships, geographic coordinates, altitude, average annual temperatures and precipitation. Representatives of all studied species complexes (with the exception of D. adjarica) had approximately the same limits of variability. Two species (D. derjugini and D. saxicola) show significant intraspecific variability. Comparisons of the genome size of parthenogenetic and bisexual species generally revealed no noticeable differences between them. Studies of triploid hybrids have shown that their genome size as a whole roughly corresponds to the sum of the average size of the diploid genome of the maternal parthenogenetic species and the haploid genome of the paternal species. The variability of genome sizes within samples of triploid hybrids was on average slightly higher than in most parthenogenetic species, but some lower than in bisexual species. The paper discusses peculiarities of reticulate speciation in this group of animals.

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Seventy-six sequences of the cytb gene region of mitochondrial DNA (1143 bp) and 27 sequences of i7 β-fib nuclear DNA (483 bp) of Lacerta strigata from 57 localities in Abkhazia, Azerbaijan, Armenia, Georgia, Iran, and Russia were analyzed. A large number of new samples were included in analysis with special focus to the species’ range at the Caucasus Isthmus. An identical topology and four supported clades (lineages) resulted for both mtDNA and sequences combined with nucleDNA (Bayesian and Maximum Likelihood). Four haplogroups (clusters) have been identified in the median cytb haplotype network. The lizards of clade A (haplogroup I) are widespread throughout the species range, while lizards of clade D (haplogroup IV) show the most limited distrubytion. No genetically unique populations of L. strigata were detected in the Caucasian xerophilous refugia. Also, no genetically distinct populations of the species were recorded in the Hyrcanian climatic refugium (Southern Caspian region). An exception is the East Hyrcanian refugium, that is characterized by the most distant clade D (IV). The territory of Ciscaucasia and the Transcaucasian depression are occupied by a single clade each: A (I) and B (II), respectively. We detected several clades distributed in the four geographic areas (contact zones): in the Greater Caucasus, Alborz, Armenian Highland, and West Turkmenian Lowland. We associate the divergence of the L. strigata phylogenetic lineage with the Turkmen-Khorasan and, in particular, the Kopet Dag orogeny, as well as with the Late Miocene fluctuations in the level of the Eastern Paratethys, while the leading factor of intraspecific differentiation is the Pleistocene regressions and transgressions of the Caspian Sea. According to the current distribution pattern and species evolutionary history, L. strigata should be assigned to the Hyrcano-Caucasian zoogeographic group.

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Investigations of the distribution, population density and breeding success of viviparous Lizards on a four-acre strip of sandy lowland heath were started in 1965. Late in the season about two acres, including the areas most favoured by the lizards, were severely burnt for over eighteen hours and subsequent search indicated that most of the population had perished. Recovery of the flora, mainly grasses (Graminae), Heather (Calluna), and a shrub element of Gorse (Ulex) and Blackberry (Rubus), restored ground cover by the end of the 1966 season. Lizard recolonisation was from the unburnt area, where a minority of the 1965 population had been found. The recovery and re-distribution of the lizard population was followed by plotting the movements of marked individuals from re-capture data. From 1966 to 1968 locutions favoured for breeding sites and hibernacula. as well as the `territories` (sensu lato) of individual lizards, increasingly approximated to those used in 1965. Population increase, based on estimates only, indicates that three breeding seasons were required to reach a level comparable to that of 1965, and there are clear signs that most of the recovery was brought about by young lizards in their first breeding seasons. Similar stations were taken up by the newcomers to those used by the 1965 population for basking, deposition of the young, and for hibernation, despite a changed flora in some of these situations. This suggests that functions of aspect and of micro-geomorphology might be of critical significance. The author has been unable to find reference to any previous observations on this subject.

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The distribution of herpetofauna on the Arabian Peninsula is generally poorly known, particularly in Saudi Arabia. The King Abdulaziz Royal Nature Reserve (KARNR) in east-central Saudi Arabia is in an area predicted to have high reptile species richness, yet there is no baseline reptile checklist for the reserve. Knowing which species occur within a protected area is vital for ensuring that conservation strategies and long-term monitoring are effective. Here, we provide the first detailed list of reptile fauna occurring in the KARNR. This study recorded a total of 31 species from 1,551 observations, including 25 lizards and six snakes. A desktop study identified three additional species, bringing the total number of herpetofaunal species known in the KARNR to 34. Two of the species found in the reserve are of conservation concern: Uromastyx aegyptia (VU) and Tropiocolotes wolfgangboehmei (DD). Through species accumulation curves we were able to determine that the sampling methods implemented during the survey were adequate, and we predicted that the species richness of the reserve is likely as much as 38 species. Prior to this study, only 82 reptile records (30 species) were known from the study area, so we add a significant number of new records to the reserve and an additional four species that were previously unknown from the region.

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Advances in genomics have greatly enhanced our understanding of mountain biodiversity, providing new insights into the complex and dynamic mechanisms that drive the formation of mountain biotas. These span from broad biogeographic patterns to population dynamics and adaptations to these environments. However, significant challenges remain in integrating large-scale and fine-scale findings to develop a comprehensive understanding of mountain biodiversity. One significant challenge is the lack of genomic data, especially in historically understudied arid regions where reptiles are a particularly diverse vertebrate group. In the present study, we assembled a de novo genome-wide SNP dataset for the complete endemic reptile fauna of a mountain range (19 described species with more than 600 specimens sequenced), and integrated state-of-the-art biogeographic analyses at the population, species, and community level. Thus, we provide a holistic integration of how a whole endemic reptile community has originated, diversified and dispersed through a mountain system. Our results show that reptiles independently colonized the Hajar Mountains of southeastern Arabia 11 times. After colonization, species delimitation methods suggest high levels of within-mountain diversification, supporting up to 49 deep lineages. This diversity is strongly structured following local topography, with the highest peaks acting as a broad barrier to gene flow among the entire community. Interestingly, orogenic events do not seem key drivers of the biogeographic history of reptiles in this system. Instead, past climatic events seem to have had a major role in this community assemblage. We observe an increase of vicariant events from Late Pliocene onwards, coinciding with an unstable climatic period of rapid shifts between hyper-arid and semiarid conditions that led to the ongoing desertification of Arabia. We conclude that paleoclimate, and particularly extreme aridification, acted as a main driver of diversification in arid mountain systems which is tangled with the generation of highly adapted endemicity. Overall, our study does not only provide a valuable contribution to understanding the evolution of mountain biodiversity, but also offers a flexible and scalable approach that can be reproduced into any taxonomic group and at any discrete environment.

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1. Squamate reptiles are central for studying phenotypic correlates of evolutionary transitions from oviparity to viviparity because these transitions are numerous, with many of them being recent. Several models of life-history theory predict thatviviparity is associated with increased female size, and thus more female-biased sexual size dimorphism

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Patterns of morphological and genetic diversity within the fringe-toed lizards of the genus Acanthodactylus have puzzled systematists since the first assessments, and none more so than the Acanthodactylus erythrurus complex. A recent study combining multi-locus sequence data and morphological characters partially resolved the situation, identifying two new species in the southern part of the range in Morocco, but leaving an unresolved “Ibero-Moroccan” clade containing much of the genetic and morphological diversity. Here we sequenced a mitochondrial marker for new samples from across much of the distribution. Our data notably increase the known ranges of various species and lineages found in Morocco, and indicate a divergent genetic lineage within one of the newly described species. While far greater numbers of genetic markers will be needed to resolve taxonomic questions, greater geographic sampling is also still needed both to delimit the species, and to identify regions where potential genetic admixture may occur.

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This study used skeletochronology to assess the relationships of age and body length of the individuals in a population of the Levant green lizard (Lacerta media), located in the Harmancik Village, Torul District, Gümüshane Province. The mean age and SVL in the adult individuals of the Harmancik population were 101.57 ± 4.04 mm and 5.31 ± 1.34 years for all individuals (101.10 ± 3.61 mm and 5.31 ± 1.03 years in adult females and 102.09 ± 4.57 mm and 5.33 ± 1.67 years in adult males). The age range varied was 4-8 years in adult males and 4-7 years in adult females. The age of the subadult males and subadult females was at 3 years, while the age of the two juveniles was 2 years. A positive correlation was found between body size (SVL) and age in adult female and male individuals of the species. A male-biased sexual size dimorphism (SSD = -0.097) was observed.

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The reproductive strategies of reptiles vary according to many factors. In lizards, intraspecific and interspecific competition, and environmental and seasonal factors affect their reproductive biology. This study aimed to conduct a comparative analysis of testis sizes in the sympatrically coexisting species, Podarcis muralis and Podarcis tauricus, located in Kofçaz, Kirklareli, Turkey, considering both intra-species and interspecies variations. Changes in body sizes and testis sizes according to months were monitored. As a result, it was determined that in both species, there was a positive correlation between body size and testis size, and that in P. tauricus, both body and testis sizes were higher compared to P. muralis, showing a significant difference. It was also observed that in the P. muralis species, the testis size reached its peak value in April (mean daily temperature 9.9°C), while in the P. tauricus species, it reached the highest value in May (mean daily temperature 15.5°C). It was found that the testis size in P. muralis reached its lowest value in August (mean daily temperature 23.8°C), while in P. tauricus, it was lowest in September (mean daily temperature 20.2°C). The fact that testis size is high in different months in these two sympatric species suggests that their active breeding periods differ.