Acta Herpetologica 17(1): 27-36, 2022 ISSN 1827-9635 (print) © Firenze University Press ISSN 1827-9643 (online) www.fupress.com/ah DOI: 10.36253/a_h-12179 A contribution to the knowledge on the diet and food preferences of Darevskia praticola (Reptilia: Lacertidae)§ Emiliya Vacheva*, Borislav Naumov Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, Gagarin Street 2, 1113 Sofia, Bulgaria § Presented at the XI International Symposium on the Mediterranean Lacertid Lizards, Lipari 27-28th September 2021 *Corresponding author. E-mail: emilia.vacheva@gmail.com Submitted on: 2021, 15th October; revised on: 2022, 6th January; accepted on: 2022, 22nd March Guest editors: Claudia Corti, Marta Biaggini Abstract. The Meadow lizard (Darevskia praticola s.l.) is one of the more poorly-studied lizard species in Europe, and no detailed data on its diet is available. We investigated a total of 180 faecal samples of D. praticola s.l. from two loca- tions in Bulgaria, and conducted a comparison between sex and age groups (adult males, adult females, and imma- tures). In addition, the correlations between the consumed prey and the available resources were also analysed. Food selectivity was analysed by comparing the faecal samples with pit-fall trap samples on the basis of abundance of prey items from particular operational taxonomic units (OTUs). Results indicate that the diet of the Meadow lizard con- tains mainly arthropods (insects and spiders) and the most abundant prey items belong to Araneae, Auchenorrhyn- cha, and Coleoptera. According to the used electivity indices none of the OTUs are highly preferred by D. praticola s.l., but Formicidae are the most avoided OTU for all sex/age groups. Differences in food preferences can be found between adults and immatures, while differences among males and females seem to be insignificant. The lack of clear differentiation between males and females could be a result of their similar size and locomotor ability. In conclusion, our results reveal that Darevskia praticola s.l. is a generalist and it shows no food specialization due to its narrow spa- tial niche. Keywords. Faecal samples, keratophagy, trophic niche, saurophagy, Sauria. INTRODUCTION Dietary studies play a key role in understanding liz- ard ecology and knowledge on feeding ecology is of cru- cial importance in establishing the interactions among species. European lizards from the family Lacertidae feed on a wide variety of arthropods and therefore they could be considered generalist predators which do not exhibit well-defined patterns of prey selection. Nevertheless, there are data which show that (at least) some lacertid species have precisely defined patterns of food selection (e.g., Díaz, 1995; Carretero, 2004). In the last decades, numerous studies on food preferences and trophic ecol- ogy of lacertids were conducted (Arnold, 1987; Carret- ero and Llorente, 1993; Capula and Luiselli, 1994; Pérez- Mellado et al., 2011; Crovetto and Salvidio, 2013; Mamou et al., 2016, 2019), although there are still many gaps in dietary research in some species and/or regions. The Meadow lizard (Darevskia praticola s.l.) occurs only in SE Europe and its distribution is limited to parts of NE Serbia, S Romania, Bulgaria, NE Greece, European Turkey, SW Russia, and NW Georgia (Sillero et al., 2014). The taxonomic status of the Meadow lizard populations from the Balkans is still not fully clarified (Doronin and Ljubisavljevic, 2014; Freitas et al., 2016; Saberi-Pirooz et al., 2018). Moreover, D. praticola is one of the least- studied European lizard species in regards of ecology and especially trophic niche. In Bulgaria, this species has a 28 Emiliya Vacheva, Borislav Naumov widely but very sporadic distribution, from the sea level up to about 1100 m a.s.l., yet is missing from the south- western part of the country (Stojanov et al., 2011). Stugren (1984) summarised all available data for D. praticola and found that quantitative analyses of the food composition were lacking. Some data on the diet are presented for the Eastern (sub)species (e.g. Terentyev and Chernov, 1949; Bannikov et al., 1971; 1977), but the trophic spectrum of D. praticola s.l. from the Balkans and adjacent areas remains unstudied. The aim of the present study was to document the diet and feeding preferences of D. praticola s.l. in Bul- garia, including possible intraspecific variation. In that sense, the following work hypotheses were formulated: 1) considering what is found in other lacertids, immatures should be unable to eat large prey items, therefore their trophic spectrum should be narrower than that of adults; 2) considering what is found in regard to microhabitat choice and sexual size dimorphism of Darevskia praticola s.l., there should be no substantial differences between sexes in their food preferences. MATERIAL AND METHODS Study area For the sampling, we chose two sites in western Bul- garia: the first site was situated at the east coast of the Ogosta Reservoir, 3.5 km from the town of Montana (43.3739° N, 23.2086° E, 180-240 m a.s.l.), and the sec- ond was situated in the Sredna Gora Mts., near Gabro- vitsa Village (42.2602° N, 23.9208° E, 430-570 m a.s.l.). According to “World-Clim v.2” (Fick and Hijmans, 2017) the annual mean temperature is 11.3 °C for Ogosta and 10.6 °C for Gabrovitsa, and the annual precipitation is respectively 624 and 568 mm (the values are extracted from the respective freely available GIS-layers with origi- nal resolution ≈ 1 km2 cell). More detailed descriptions of the studied sites are given by Vacheva et al. (2020). Sampling For the purpose of the study, we used a faecal sam- ples analysis: a non-invasive method which, despite of some limitations (e.g., impossibility for prey recognition in such taxonomic level as by direct analysis of the stom- ach content), provides adequate results in dietary studies (Bombi and Bologna, 2002; Luiselli et al., 2011; Pérez- Mellado et al., 2011). Lizards were captured in 2013, 2014 and 2016 in Ogosta and in 2017 and 2018 for Gabro- vitsa. A total of 53 field days were conducted, as follows: Ogosta – 28 days and Gabrovitsa – 25 days. Lizards were captured by hand and were measured (snout-vent length, SVL) with a transparent ruler to the nearest 1 mm. For each captured lizard, sex and age class were recorded. Age was not determined directly but estimated from body size and sexual secondary characters, so two age groups were defined: adults (SVL > 45 mm) and imma- tures (SVL between 24-44 mm). All of the captured liz- ards were placed separately in plastic boxes until defeca- tion and after that, released at the site of capture. Faecal samples from each lizard were preserved in separate test tubes with ethanol for further examination under stereo- scopic microscope (magnification 10-40X). Invertebrate remnants were identified to the lowest possible system- atic level (in most cases to the level of Order). Collect- ed invertebrates (both from the faecal and trap samples) were categorized with regards to their hardness (hard, intermediate, soft) and evasiveness (sedentary, interme- diate, evasive) in accordance with Verwaijen et al. (2002) and Vanhooydonck et al. (2007). Food resources were evaluated by pit-fall traps, which is a widely used method in similar studies (see Vacheva and Naumov, 2020 and references therein). A total of 24 pit-fall traps were exposed (10 meters apart) in four dif- ferent habitat types (river bed, meadow, deciduous forest and the ecotone between the meadow and the forest). This was done only in Gabrovitsa for 23 and 17 days in spring, and 16 and 23 days in summer for 2017 and 2018 respec- tively. Collected invertebrates were identified to the low- est possible taxonomic level. We use the term “operational taxonomic unit” (abbreviated as OTU) instead of the term “taxon” for the invertebrates from both feacal samples and traps, because here the individual taxa are considered without taking into account their rank. Statistics Taxonomic diversity in the diet of D. praticola s.l. was analysed by Rényi’s index family (diversity profiles), which is considered one of the most useful methods for ordering communities according to their diversity (see Tóthmérész, 1995). The significance of differences in diversity between the separate samples (adult males, adult females, and immatures) was assessed by a permutation test, based on the diversity indices of Shannon (H) and Simpson (1-D). Food selectivity was analysed by comparing the faecal samples with trap samples on the basis of abun- dance of individuals from particular OTUs (standardized toward total number of individuals in the sample). The electivity was described by the indices of Ivlev (E) and Vanderploeg and Scavia (E*) (see Ivlev, 1961 and Vander- 29Diet of Darevskia praticola ploeg and Scavia, 1979, respectively). Both indices take values from -1 to +1, where the positive values indicate that the respective component is preferred, and the nega- tive – it is avoided (for a detailed review of the electivity indices see Lechowicz, 1982). Spearman’s rank correlation coefficient was used to test for correlation between abundance and frequency of the prey items. A Chi-square test was used for the com- parison between sexes and between age groups, regarding the categories of evasiveness and hardness of the nutri- tional components. Calculations of the diversity indices, as well as sta- tistical tests, were done using PAST 3.21 (Hammer et al., 2001). The electivity indices were calculated in Microsoft Excel (2010) after manual input of the respective formulas. RESULTS A total of 180 faecal samples from D. praticola s.l. were collected – 31 from Ogosta and 149 from Gabrovit- sa. Among them, 136 from adults (70 male and 66 female) and 44 immatures. The distribution of the material from the faecal samples of Darevskia praticola from Ogosta and Gabrovitsa is presented in Appendices 1 and 2. The identifiable invertebrate remnants could be attributed to 622 individual specimens: 100 from Ogosta and 522 from Gabrovitsa (Appendix 3). The average number of inverte- brates found in the faecal pellets was 3.46 (3.23 for Ogosta and 3.74 for Gabrovitsa), and the maximum was 15. A total of 23 OTUs were identified in the faecal sam- ples, and most of them were the same for both study sites. In Gabrovitsa more OTUs were observed – 22, in contrast to Ogosta where only 15 OTUs were observed (Appendices 1 and 2). Dermaptera, Formicidae, Gas- tropoda, Mecoptera, Myriapoda, Pseudoscorpiones, and Scorpiones were recovered only from Gabrovitsa, while Hemiptera were found only in the samples from Ogos- ta. Among all of the OTUs, the most abundant and fre- quent for Ogosta were Araneae and Coleoptera, as well as Blattodea but only by frequency of occurrence, while in Gabrovitsa predominant by both number and frequency were Araneae, Auchenorrhyncha, and Insecta indet. (Fig. 1). The correlation between abundance and frequency of occurrence of OTUs for the two sites was positive and with very high level of statistical significance (Table 1). The total number of OTUs registered in the pit- fall traps at Gabrovitsa was 25. Most abundant OTUs were Formicidae, Aranea, and Coleoptera (Appendix 3). According to the electivity indices, none of the OTUs were highly preferred by D. praticolа s.l. (Table 2). The highest values for both indices were observed for Blat- todea for males, for Insecta larvae for females and for Hymenoptera (excl. Formicidae) in immatures. On the other hand, with lowest values of the indices (close to -1) were Formicidae for all of the three sex/age groups (the index values for immatures are not presented in the table). According to the Rényi’s profiles (Fig. 2) the high- est diversity of the diet was observed in males, and like- wise diversity in the diet of adults was higher than in immatures. Statistically significant differences between adult males and immatures were established for the sam- ple from Gabrovitsa with respect to the Shannon index (Table 3); the number of registered OTUs in adults was 22, while for immatures this was only 13. While the total number of OTUs was lower for Ogosta, this could be due to the lower sample size, and a total of 13 OTUs were observed in adults, compared to only 9 in immatures. OTUs presented only in adults were Acari, Dermaptera, Gastropoda, Hemiptera, Heteroptera, Isopoda, Mecop- tera, Myriapoda, Pseudoscorpiones and Scorpiones. None of these OTUs were present in immatures only. The total number of observed OTUs in males was 21, while in females this was 19; for Ogosta there were 11 and 8 OTUs respectively, and for Gabroivitsa, where the sample size was larger – 20 and 18 respectively. OTUs observed only in males were Isopoda, Hemiptera, Dermaptera, and Scorpiones, while in females Lepidoptera, Mecoptera, and Myriapoda, but represented by single items. Regarding the evasiveness of the prey, the highest values in faecal samples at both sample sites were seden- tary prey items, and in terms of hardness, soft prey items were consumed more often (Table 4). The results of Chi- square test did not show statistically significant difference between all age/sex groups, in regards to neither evasive- ness nor hardness of the prey items (Table 5). In addition, parts of ingested tails and finger were discovered in the faecal samples. Cases of saurophagy were established in two adult males and one female from Gabrovitsa, i.e., in 2.01% of the samples from Gabrovitsa and 1.66% of total sample size. Keratophagy (the con- sumption of shed skin) was observed in two adults – a male and a female, or 1.34% of the samples from Gabro- vitsa and 1.11% from the total sample size. Non-organic matter (grit) was recorded in three individuals, and plant matter was recorded in nine adults (five males and four females), which presents 5% from the total sample size (Appendix 2). DISCUSSION Our results suggest that D. praticola s.l. feeds main- ly on arthropods, like many other lacertids, with insects 30 Emiliya Vacheva, Borislav Naumov being the predominant group – more than 60% of the total items recovered from the faecal pellets. Seven groups (Araneae, Auchenorrhyncha, Coleoptera, Insecta indet., Formicidae, and other Hymentoptera) composed more than 70% of the consumed prey, and among them the most abundant food source were spiders (more than 30%.) We also recorded OTUs that could be described as “dangerous prey”, such as Dermaptera, Myriapоda, and Scorpiones, which were present with single individuals and in adults only. In the available literature there are no detailed data about diet and food preferences in D. praticola s.l. In a few sources, a brief description of the most common prey was provided: Terentyev and Chernov (1949) state that the food of Darevskia praticola s.l. consists mainly of beetles (about 50%), orthopterans, arachnids, and dipter- ans. Bannikov et al. (1971) assign small insects, spiders, earthworms, molluscs and other invertebrates as prey to the Meadow lizards, specifying that among insects, small beetles, ants, orthopterans, leafhoppers, caterpillars, earwigs, aphids, as well as woodlice were the most con- sumed (Bannikov et al., 1977). The above mentioned has been confirmed by other authors (e.g., Orlova and Terty- shnikov, 1979; Tertyshnikov, 2002) and some anecdotal Fig. 1. Percentage of the invertebrates by OTUs according to: total number of specimens in the faecal samples of D. praticola (N); number of faecal samples in which the OTU occurs (Fr); total number of specimens, collected by pitfall traps (Tr). OTUs are in descending order according to the values of N. 31Diet of Darevskia praticola data are reported in Stugren, 1984. Bischoff (1976) points out that the meadow lizard, like its relatives, preys on all edible invertebrates that can be overwhelmed. Differences in food preferences were found between adult males and immatures, and the diet of adults in gen- eral was more diverse than that of immatures. It could be due to size limitation of the immatures (i.e., impossi- bility to consume large invertebrates), but also could be (at least partially) a result of the bias in terms of sample size differences (much smaller in immatures). In adults, the established lack of clear differentiation between males and females could be a result of their similar size and locomotor ability. In term of evasiveness of the prey, less mobile prey categories were predominant, which can be explained by the fact, that the Meadow lizard is ground-dwelling and comparatively slow-moving species (Arnold, 1987). Regarding the hardness of the prey, predominant were soft prey categories. In view of the relatively small head size in comparison to body size (personal data), D. pra- ticola s.l. probably avoids highly chitinized invertebrates. Cannibalism and saurophagy in general, has been observed more often in island populations, where it could be caused by high lizard density and scarce food Fig. 2. Diversity profiles of the diet in males (M), females (F), and immatures (Sub) of D. praticola according to the abundance of OTUs in the faecal samples from Ogosta (A) and Gabrovitsa (B). Table 1. Correlation (Rho) between abundance and frequency of OTUs in the faecal samples of male (M), female (F) and immature (Sub) Darevskia praticola, and its statistical significance (P). Rho P Ogosta M 0.84 0.0023 F 0.77 0.0476 Sub 0.89 0.0179 Gabrovitsa M 0.97 0.0000 F 0.92 0.0000 Sub 0.83 0.0014 Table 2. List of the most abundant (r > 5%) OTUs from the faecal samples of males (M), females (F), and immatures (Sub) of Darevs- kia praticola according to the electivity indices of Ivlev (E) and Van- derploeg & Scavia (E*); r = percentage in the faecal samples, p = percentage in the pitfall traps.   OTU r p E E* M Blattodea 5.19% 0.55% 0.8084 0.3087   Hymenoptera (eF) 5.19% 2.17% 0.4103 -0.3516   Araneae 27.36% 18.39% 0.1961 -0.5402   Auchenorrhyncha 8.49% 7.14% 0.0865 -0.6147   Coleoptera 5.19% 12.81% -0.4234 -0.8497   Formicidae 12.74% 36.60% -0.4837 -0.8695 F Insecta (larvae) 6.02% 1.22% 0.6630 0.0611   Araneae 31.94% 18.39% 0.2694 -0.4307   Auchenorrhyncha 12.04% 7.14% 0.2555 -0.4428   Coleoptera 9.72% 12.81% -0.1369 -0.7038   Formicidae 7.87% 36.60% -0.6461 -0.9061 Sub Hymenoptera (eF) 6.38% 2.17% 0.4927 0.3822   Auchenorrhyncha 17.02% 7.14% 0.4091 0.2891   Araneae 30.85% 18.39% 0.2532 0.1213   Coleoptera 8.51% 12.81% -0.2016 -0.3286 32 Emiliya Vacheva, Borislav Naumov resource (Pérez-Mellado and Corti, 1993; Castilla and Van Damme, 1996; Cooper et al., 2015), while it is rare in continental populations (Simović and Marković, 2013). Cases of saurophagy were more frequent in males, as males often display more aggressive behaviour to other conspecifics (Castilla, 1995), and the presence in females mentioned here is interesting. On the base of the pho- lidosis, we determined that the remnants of the con- sumed lizard parts in the faecal samples of D. praticola s.l. belong to representatives of Lacertidae family, but because of the presence of two other syntopic lacertids in Gabrovitsa (Lacerta viridis (Laurenti, 1768) and Podar- cis muralis (Laurenti, 1768)), we can suggest only sau- rophagy, as far as there are no direct evidence for canni- balism. Until now, cases of (partial) saurophagy, were not established for Darevskia praticola s.l., and this is the first observation to our knowledge. The only known record of saurophagy in another member of the Darevskia genus was mentioned for an adult female Darevskia braun- eri (Méhely, 1909) that fed on a juvenile Lacerta agilis (Golynsky and Doronin, 2014). Another interesting feeding behaviour, keratophagy (the ingestion of shed skin), was observed for the first time in D. praticola s.l. Keratophagy was previously known for only four lacertids (Mitchell et al., 2006 and references therein) but in more detailed dietary study it was recorded for the Viviparous lizard Zootoca vivipara (Lichtenstein, 1823) (see Vacheva, 2018; Vacheva and Naumov, 2020), where keratophagy was present in more than 9% of the samples, as well as in two other lacertids (Podarcis muralis, and Lacerta viridis), hence this event seems to be more common than previously thought and probably has more complex and important evolutionary significance. The Meadow lizard is a species with very limited spatial niche and it is a typical forest inhabitant, strong- ly associated with deciduous forests (mostly oak forests) Table 3. Diversity indices of the diet in males (M), females (F), and immatures (Sub) of Darevskia praticola, and the statistical significance of the differences between them (Permutation P). Index value Permutation P Ogosta Gabrovitsa Ogosta Gabrovitsa Simpson 1-D M 0.82 0.86 M vs. F 0.29 0.36 F 0.78 0.82 M vs. Sub 0.07 0.19 Sub 0.75 0.80 F vs. Sub 0.42 0.72 Shannon H M 1.95 2.37 M vs. F 0.17 0.14 F 1.76 2.16 M vs. Sub 0.09 0.002 Sub 1.70 1.95 F vs. Sub 0.71 0.1 Table 4. Division of the invertebrates per categories of evasiveness (E1, E2, and E3) and hardness (H1, H2, and H3) as a percentage of all of the identified invertebrates in the faecal samples of male (M), female (F), and immature (Sub) Darevskia praticola. Ogosta Gabrovitsa M F Sub M F Sub Evasiveness E1 44.68% 48.00% 55.00% 53.68% 60.82% 63.29% E2 25.53% 24.00% 10.00% 24.21% 22.16% 15.19% E3 29.79% 28.00% 35.00% 22.11% 17.01% 21.52% Hardness H1 59.57% 68.00% 80.00% 60.53% 56.70% 54.43% H2 8.51% 0.00% 0.00% 3.68% 3.61% 2.53% H3 31.91% 32.00% 20.00% 35.79% 39.69% 43.04% Table 5. Chi-square test for the differences between male, female, and immature Darevskia praticola in regards to evasiveness and hardness of the prey items. Ogosta Gabrovitsa Evasiveness χ2 2.14 4.73 df 4 4 P 0.71 0.32 Hardness χ2 5.49 1.53 df 4 4 P 0.24 0.82 33Diet of Darevskia praticola (Vacheva et al., 2020). As an active and effective ther- moregulator, with a preferred temperature close to the lower limit of mean body temperatures in comparison to other European lacertids (Ćorović and Crnobrnja- Isailović, 2018), it has to choose suitable thermal micro- habitats. 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Ecol. 16: 842-850. 35Diet of Darevskia praticola APPENDIX 1 Distribution of the material from the faecal samples of Darevskia praticola from Ogosta per OTU (M, F, and Sub: males, females and imma- tures; Evas.: evasiveness category, E1, E2, and E3 refer to sedentary, intermediate, and evasive, respectively; Hard.: hardness category, H1, H2, and H3 refer to soft, intermediate, and hard, respectively; N: number of identified specimens; Fr: number of the faecal samples in which OTU occurs; eF: except Formicidae).  OTU Evas. Hard. M F Sub Total N Fr. N Fr. N Fr. N Fr. Acari E1 H1 1 1 1 1 0 0 2 2 Araneae E1 H1 15 12 9 5 9 6 33 23 Arthropoda (indet.) 0 0 0 0 1 1 1 1 Auchenorrhyncha E1 H3 0 0 0 0 1 1 1 1 Blattodea E3 H1 2 2 3 1 3 3 8 6 Coleoptera E2 H3 12 8 6 4 2 2 20 14 Diptera E3 H1 6 2 1 1 2 1 9 4 Hemiptera (indet.) 2 2 0 0 0 0 2 2 Hymenoptera (eF) E3 H3 3 1 2 2 1 1 6 4 Insecta (indet.) 4 3 0 0 0 0 4 3 Insecta (larvae) E1 H1 0 0 2 1 0 0 2 1 Isopoda E1 H2 1 1 0 0 0 0 1 1 Lepidoptera E3 H1 0 0 1 1 1 1 2 2 Opiliones E1 H1 4 3 0 0 1 1 5 4 Orthoptera E3 H2 4 4 0 0 0 0 4 4 APPENDIX 2 Distribution of the material from the faecal samples of Darevskia praticola from Gabrovitsa per OTU (M, F and Sub: males, females and immatures; Evas.: evasiveness category, E1, E2, and E3 refer to sedentary, intermediate, and evasive, respectively; Hard.: hardness category, H1, H2, and H3 refer to soft, intermediate, and hard, respectively; N: number of identified specimens; Fr: number of the faecal samples in which OTU occurs; eF: except Formicidae OPI: other prey items).  OTU Evas. Hard. M F Sub Total N Fr. N Fr. N Fr. N Fr. Acari E1 H1 7 4 0 0 0 0 7 4 Araneae E1 H1 58 41 69 46 29 20 156 107 Arthropoda (indet.) 2 2 1 1 1 1 4 4 Auchenorrhyncha E1 H3 18 17 26 22 16 13 60 52 Blattodea E3 H1 11 9 7 7 2 2 20 18 Coleoptera E2 H3 11 11 21 16 8 7 40 34 Dermaptera E2 H1 3 3 0 0 0 0 3 3 Diptera E3 H1 8 7 5 4 3 3 16 14 Formicidae E2 H3 27 15 17 8 4 4 48 27 Gastropoda E1 H3 1 1 3 2 0 0 4 3 Heteroptera E2 H1 5 4 3 1 0 0 8 5 Hymenoptera (eF) E3 H3 11 8 10 5 6 2 27 15 Insecta (indet.) 20 19 21 20 14 12 55 51 Insecta (larvae) E1 H1 9 8 13 13 2 2 24 23 Isopoda E1 H2 2 1 0 0 0 0 2 1 Lepidoptera E3 H1 7 8 4 4 4 4 15 16 Mecoptera E2 H1 0 0 1 1 0 0 1 1 Myriapoda E2 H1 0 0 1 1 0 0 1 1 36 Emiliya Vacheva, Borislav Naumov  OTU Evas. Hard. M F Sub Total N Fr. N Fr. N Fr. N Fr. Opiliones E1 H1 4 4 6 5 3 3 13 12 Orthoptera E3 H2 5 5 7 7 2 2 14 14 Pseudoscorpiones E1 H1 2 2 1 1 0 0 3 3 Scorpiones E1 H1 1 1 0 0 0 0 1 1 OPI (cannibalism) 1 1 1 3 OPI (keratophagy) 1 1 0 2 OPI (grit) 3 0 0 3 OPI (plant material) 5 4 0 9 APPENDIX 3 Distribution of the material from the pitfall traps in Gabrovitsa per OTU (Evas.: evasiveness category, E1, E2, and E3 refer to sedentary, intermediate, and evasive, respectively; Hard.: hardness category, H1, H2, and H3 refer to soft, intermediate, and hard, respectively; eF: except Formicidae). OTU Evas. Hard. N Acari E1 H1 832 Aphidoidea E1 H1 22 Araneae E1 H1 1839 Archaeognatha E1 H1 9 Auchenorryncha E1 H3 714 Blattodea E3 H1 55 Coleoptera E2 H3 1281 Collembola E1 H1 83 Dermaptera E2 H1 4 Diptera E3 H1 586 Formicidae E2 H3 3661 Gastropoda E1 H3 16 Heteroptera E2 H1 81 Hymenoptera (eF) E3 H3 217 Insecta (larvae) E1 H1 122 Isopoda E1 H2 57 Lepidoptera E3 H1 27 Mecoptera E2 H1 1 Myriapoda E2 H1 42 Neuroptera E2 H1 3 Oligochaeta E1 H1 10 Opiliones E2 H1 168 Orthoptera E3 H2 168 Pseudoscorpiones E1 H1 2 Trichoptera E3 H1 2 XI International Symposium on the Mediterranean Lacertid Lizards Marco Mangiacotti1, Pietro Lo Cascio2, Claudia Corti2, Marta Biaggini2, Miguel Angel Carretero2, Petros Lymberakis2 The directional testes asymmetry increases with temperature in seven plateau brown frog (Rana kukunoris) populations Hai Ying Li1, Man Jun Shang2, Jie Guo2, Bo Jun Chen2, Peng Zhen Chen2, Tong Lei Yu1,* Influence of tail injury on the development of Neotropical elegant treefrog tadpoles Ana Glaucia da Silva Martins1,#, Raoni Rebouças2,3,*,#, Isaias Santos1, Adão Henrique Rosa Domingos1, Luís Felipe Toledo2 The effect of weight and prey species on gut passage time in an endemic gecko Quedenfeldtia moerens (Chabanaud, 1916) from Morocco Jalal Mouadi1,*, Panayiotis Pafilis2, Abderrafea Elbahi3, zahra Okba3, Hassan ElOuizgani3, El Hassan El Mouden4, Mohamed Aourir1 A contribution to the knowledge on the diet and food preferences of Darevskia praticola (Reptilia: Lacertidae)§ Emiliya Vacheva*, Borislav Naumov First report on two loggerhead turtle (Caretta caretta) nests in the Aeolian Archipelago (Southern Italy) Monica Francesca Blasi1,*, Sandra Hochscheid2, Roberta Bardelli3, Chiara Bruno1, Carolina Melodia1, Perla Salzeri1, Paolo De Rosa4 and Paolo Madonia5 Threatened and extinct amphibians and reptiles in Italian natural history collections are useful conservation tools Franco Andreone1,*, Ivano Ansaloni2, Enrico Bellia3, Andrea Benocci4, Carlotta Betto5, Gabriella Bianchi6, Giovanni Boano7, Antonio Borzatti de Loewenstern8, Rino Brancato9, Nicola Bressi10, Stefano Bulla11, Massimo Capula12, Vincenzo Caputo Barucchi13, P Re-description of external morphology and factors affecting body and tail shape of the stone frog tadpoles’ Brena da Silva Gonçalves1,*, Carla. D. Hendges2, Bruno Madalozzo2, Tiago G. Santos2,3 Preliminary data on the diet of Chalcides chalcides (Squamata: Scincidae) from Northern Italy Andrea Ciracì1, Edoardo Razzetti2, Maurizio Pavesi3, Daniele Pellitteri-Rosa4,* The high diversity and phylogenetic signal of antipredator mechanisms of the horned frog species of Proceratophrys Miranda-Ribeiro, 1920 (Amphibia: Anura: Odontophrynidae) Cássio Zocca1,2,*, Ricardo Lourenço-de-Moraes3, Felipe S. Campos4, Rodrigo B. Ferreira1,2,5