Diversifying selection and color-biased dispersal in the asp viper.

BACKGROUND: The presence of intraspecific color polymorphism can have multiple impacts on the ecology of a species; as a consequence, particular color morphs may be strongly selected for in a given habitat type. For example, the asp viper (Vipera aspis) shows a high level of color polymorphism. A blotched morph (cryptic) is common throughout its range (central and western Europe), while a melanistic morph is frequently found in montane populations, presumably for thermoregulatory reasons. Besides, rare atypical uniformly colored individuals are known here and there. Nevertheless, we found in a restricted treeless area of the French Alps, a population containing a high proportion (>50%) of such specimens. The aim of the study is to bring insight into the presence and function of this color morph by (i) studying the genetic structure of these populations using nine microsatellite markers, and testing for (ii) a potential local diversifying selection and (iii) differences in dispersal capacity between blotched and non-blotched vipers. RESULTS: Our genetic analyses support the occurrence of local diversifying selection for the non-blotched phenotype. In addition, we found significant color-biased dispersal, blotched individuals dispersing more than atypical individuals. CONCLUSION: We hypothesize that, in this population, the non-blotched phenotype possess an advantage over the typical one, a phenomenon possibly due to a better background matching ability in a more open habitat. In addition, color-biased dispersal might be partly associated with the observed local diversifying selection, as it can affect the genetic structure of populations, and hence the distribution of color morphs

Monitoraggio della Biscia tassellata, Natrix tessellata (Laurenti, 1768) nel Cantone Ticino (Svizzera)

ITALIAN: Sulla base dei dati raccolti durante due anni di monitoraggio abbiamo valutato la distribuzione attuale delle popolazioni ticinesi di Biscia tassellata (Natrix tessellata). La valutazione è stata effettuata tenendo conto del fatto che il mancato rilevamento della specie sul campo non indica necessariamente una sua assenza: infatti, grazie ad un modello basato su un approccio di tipo mark-recapture, abbiamo calcolato la probabilità di rilevamento, che risulta pari al 61.2% (± 6.8%), e la proporzione di siti occupati, pari al 78.0% (± 7.9%) dei siti conosciuti. Localmente, alcune piccole popolazioni situate lungo corsi d’acqua secondari appaiono soggette a dinamiche di regressione o estinzione, probabilmente in seguito al deterioramento della qualità degli habitat. Al contrario, le popolazioni che si trovano sulle rive dei laghi (Verbano e Ceresio) e sui corsi d’acqua principali (Ticino, Brenno, Maggia, Vedeggio e Tresa) sono ben distribuite sul territorio e caratterizzate da effettivi localmente abbondanti. La situazione è dunque da considerare sostanzialmente stabile. Lo statuto di specie minacciata secondo la Lista Rossa è tuttavia pienamente giustificato per N. tessellata, soprattutto considerate l’esiguità dell’area occupata a livello svizzero e la fragilità degli ambienti acquatici ai quali essa è strettamente legata. I dati raccolti in questo studio saranno utilizzati per l’allestimento di un piano d’azione specifico per la conservazione delle popolazioni di N. tessellata in Ticino. ENGLISH: Based on two years of field work, we surveyed the distribution of Dice Snakes (Natrix tessellata) populations in the Canton of Ticino (Switzerland). Imperfect detection has been taken into account in order to avoid underestimation of the species range: we therefore used a model based on a mark-recapture-like approach to estimate detection probability, which is 61.2% (± 6.8%), and site occupancy, which is 78.0% (± 7.9%). We observed local declines or extinctions of some small opulations inhabiting secondary streams, apparently because of the habitat deterioration. However, populations located along lakes (Ceresio, Verbano) and main rivers (Ticino, Brenno, Maggia, Vedeggio and Tresa) are widely distributed and show rather high densities. Therefore, the status of N. tessellata in Ticino should be considered as stable. The endangered status reported by the Swiss Red List for these species is adequate because of the small area occupied at national level and vulnerability of freshwater ecosystems. A specific action plan in favour of the conservation of Dice Snakes populations in Ticino, Switzerland, will now be based on the collected data

Mountain vipers in central-eastern turkey: Huge range extensions for four taxa reshape decades of misleading perspectives

2-s2.0-85084982255—Turkey harbors a high diversity of viperid snakes, many with a high threat level on the International Union for Conservation of Nature (IUCN) Red List, yet perception about even basic topics, such as distributions and conservation statuses, remain poor. We initiated a multi-year project 7 y ago to compensate these shortcomings and present herein dramatically improved information on the status of mountain vipers of central-eastern Anatolia (Asian Turkey): Bolkar Viper (Montivipera b. bulgardaghica), Albizona Viper (M. b. albizona), Wagner’s Viper (M. wagneri), and partly Ottoman Viper (M. xanthina). The data originate from our fieldwork and a comprehensive search of all records available, including information from literature, online resources, locals, and herpetological experts. This resulted in 51 new localities, complemented by 36 published records, which were refined with new information, including four corrected/removed records and two records that were combined with new records due to their proximity. We summarized all records with precise information in a supplemented list of 85 localities, which is compared to current literature and the range maps available on the IUCN Red List of Threatened Species, the global standard reference for consultation on range maps and conservation status of species. Consequently, we report on large range extension of > 100 km in all four mountain viper taxa, increase the extent of occurrence for each viper taxon 4–8 times, reduce the distribution gaps between all pairs of parapatric, related, and ecologically similar mountain vipers, and discuss taxa delimitation, putative contact zones and conservation aspects. © 2020. Konrad Mebert.Mohamed bin Zayed Species Conservation Fund: 13057971, 150510677, 160513040, 170516395, 2017/18Acknowledgments.—We dedicate this article to our beloved and esteemed co-author, contributor and collaborator, Dr. Bayram Göçmen, who passed away during the final steps of this study. Field work permits focusing on vipers (permission numbers 20210, 183897 and 101792) were issued by the Republic of Turkey Ministry of Agriculture and Forestry, General Directorate of Nature Conservation and National Parks. This work was partly supported by the Wilhelm Peters Fund 2013 administered by the main body of the German Herpetological Society, respectively, Deutsche Gesellschaft für Herpetologie und Terrarienkunde (DGHT), and also DGHT-Zürich, Switzerland, the JCE private funding, and in particular the Mohamed bin Zayed Species Conservation Fund, project nos. 13057971 (2014), 150510677 (2015), 160513040 (2016), 170516395 (2017/18). The authors thank Şevket Gültekin, Adem Adakul, Mücahit Çakmak, Çağatay Altin, Mehmet Akif Bozkurt, Burhan Sarikaya, Thomas Ott, Murat Özel, Mert Elverici, Mahmut Aydoğdu, Özer Camci, and Osman Özkan for their assistance during our field surveys. We also thank all the persons providing valuable material, such as photos and locality information, which are explicitly named for their respective provisions in the locality list and figures.We dedicate this article to our beloved and esteemed co-author, contributor and collaborator, Dr. Bayram G??men, who passed away during the final steps of this study. Field work permits focusing on vipers (permission numbers 20210, 183897 and 101792) were issued by the Republic of Turkey Ministry of Agriculture and Forestry, General Directorate of Nature Conservation and National Parks. This work was partly supported by the Wilhelm Peters Fund 2013 administered by the main body of the German Herpetological Society, respectively, Deutsche Gesellschaft f?r Herpetologie und Terrarienkunde (DGHT), and also DGHT-Z?rich, Switzerland, the JCE private funding, and in particular the Mohamed bin Zayed Species Conservation Fund, project nos. 13057971 (2014), 150510677 (2015), 160513040 (2016), 170516395 (2017/18). The authors thank ?evket G?ltekin, Adem Adakul, M?cahit ?akmak, ?a?atay Altin, Mehmet Akif Bozkurt, Burhan Sarikaya, Thomas Ott, Murat ?zel, Mert Elverici, Mahmut Aydo?du, ?zer Camci, and Osman ?zkan for their assistance during our field surveys. We also thank all the persons providing valuable material, such as photos and locality information, which are explicitly named for their respective provisions in the locality list and figures