CHAPTER 10. AMPHIBIANS OF THE PALAEARCTIC REALM Figure 1. Summary of Red List categories Brandon Anthony, J.W. Arntzen, Sherif Baha El Din, Wolfgang Böhme, Dan Palaearctic Realm contains 6% of all globally threatened amphibians. The Palaearctic accounts for amphibians in the Palaearctic Realm. CogĄlniceanu, Jelka Crnobrnja-Isailovic, Pierre-André Crochet, Claudia Corti, for only 3% of CR species and 5% of the EN species, but 9% of the VU species. Hence, on the The percentage of species in each category Richard Griffiths, Yoshio Kaneko, Sergei Kuzmin, Michael Wai Neng Lau, basis of current knowledge, threatened Palaearctic amphibians are more likely to be in a lower is also given. Pipeng Li, Petros Lymberakis, Rafael Marquez, Theodore Papenfuss, Juan category of threat, when compared with the global distribution of threatened species amongst Manuel Pleguezuelos, Nasrullah Rastegar, Benedikt Schmidt, Tahar Slimani, categories. The percentage of DD species, 13% (62 species), is also much less than the global Max Sparreboom, ùsmail Uøurtaû, Yehudah Werner and Feng Xie average of 23%, which is not surprising given that parts of the region have been well surveyed. Red List Category Number of species Nevertheless, the percentage of DD species is much higher than in the Nearctic. Extinct (EX) 2 Two of the world’s 34 documented amphibian extinctions have occurred in this region: the Extinct in the Wild (EW) 0 THE GEOGRAPHIC AND HUMAN CONTEXT Hula Painted Frog Discoglossus nigriventer from Israel and the Yunnan Lake Newt Cynops Critically Endangered (CR) 13 wolterstorffi from around Kunming Lake in Yunnan Province, China. In addition, one Critically Endangered (EN) 40 The Palaearctic Realm includes northern Africa, all of Europe, and much of Asia, excluding Endangered species in the Palaearctic Realm is considered possibly extinct, Scutiger macu- Vulnerable (VU) 58 the southern extremities of the Arabian Peninsula, the Indian Subcontinent (south of the latus from central China. This represents 1% of the 130 possibly extinct species in the world. Near Threatened (NT) 48 crest of the Himalaya), Southeast Asia, and the southern parts of China. It is by far the Clearly, as with the Nearctic, there is little in the way of overall discernible pattern so far in Least Concern (LC) 245 largest of the six biogeographic realms. Palaearctic amphibian extinctions. Data Deficient (DD) 62 The Palaearctic Realm is dominated by the Eurasian tectonic plate, which comprises all of Europe Despite a lower overall threat to the amphibian fauna in the Palaearctic compared with Total Number of Species 468 and most of Asia. Over the past 60 million years, the African, Arabian and Indian plates have collided some other regions, many widespread Least Concern species are seriously threatened in many with and compressed the Eurasian plate, forming an extensive array of mountain ranges, generally parts of their ranges. Many countries in Europe, report high levels of threat to their amphibian 13% 0.4% 3% 9% running in an east-west direction. These ranges include: the Pyrenees; the Alps; the Carpathians; the faunas. For example, Switzerland lists 70% of its species as nationally threatened (Schmidt and Balkan mountains; the Caucasus; the mountains of Turkey, Iran, Afghanistan, Pakistan and central Zumbach 2005), even though only one of these species is globally threatened. Asia; and the Himalaya. The northern part of the African Plate and most of the Arabian plate are 12% now dominated by a Palaearctic fauna, whereas the fauna on the Indian Plate is overwhelmingly Indomalayan (as is the fauna on the south-eastern part of the Eurasian Plate). Although the Palaearc- SPECIES RICHNESS AND ENDEMISM tic has an extensive land connection with the Afrotropical Region, there is relatively little mixing of the faunas, due to the barrier to dispersal formed by the Sahara and Arabian Deserts, particularly Species Richness and Endemism Across Taxa 10% for organisms such as amphibians. However, there is much more overlap with the Indomalayan fauna, and the boundary between the two regions is hard to delineate in China. The 468 native amphibian species in the Palaearctic Realm represent 8% of the currently 52% For the reasons given above, the southern part of the region is much more mountain- known global total of 5,915 species. Of these 468 species, 260 (or 56%) are endemic to the ous than the northern part, and includes the highest mountains in the world, peaking at Palaearctic (Table 1). Salamanders, newts, frogs and toads are present in the region, but there Sagarmatha (Mount Everest) at 8,850m. All of the world’s mountains higher than 8,000m are no caecilians. Anurans account for over three-quarters (77%) of the species. Endemism is occur in the Himalayan and Karakorum ranges. much higher in the salamanders and newts (86%) compared with the frogs and toads (47%). Boreal coniferous forests dominate the northern part of the region, through Scandinavia This is presumably a reflection of the generally much smaller range sizes among salamanders, and Russia. Further to the south, both the western and eastern parts of the region were and that the families Salamandridae and Hynobiidae radiated mainly in the Palaearctic originally covered in mixed and broad-leaved temperate forests, giving way to steppe lands (see, for example, Weisrock et al. 2006). Of the 15 amphibian families that are native to the in the central part of the region. However, very little remains of the original temperate forest region, only three are endemic (Table 1). Only 19 species (4% of the species in the region) habitat through most of the region. In keeping with the topography, habitat diversity is greater are members of these endemic families, although the salamander family Hynobiidae occurs in the southern part of the region, ranging from deserts, to grassland, to Mediterranean-type only marginally in the Indomalayan Region and is predominantly Palaearctic. scrubland, and to coniferous forests. Under current climatic conditions, there is essentially no isolation between the Pa- The Palaearctic Realm has a very uneven human population density (approximately 32 laearctic and Indomalayan Regions, especially in China, and the boundary between these people per square kilometre in Europe in 2005, compared with 137 in China, 339 in Japan, two faunas is somewhat arbitrary. The effect of this indistinct boundary is to reduce the but only 8 in Russia and 11 in Saudi Arabia). The percentage of the population living in rural level of endemism of both regions. Summaries of the amphibian fauna of the Palaearctic areas also varies greatly, ranging from 11.5% in Saudi Arabia, to 26.7% in Europe and Rus- are provided by Borkin (1999) and Zhao (1999). sia, 34.3% in Japan, and 59.5% in China. In general, most of the people in the region are There are 66 genera (14% of the global total) occurring in the region, of which 22 (33%) concentrated in eastern Asia and western Europe. The gross income per capita also varies are also endemic. Endemism at the generic level is much higher among the salamanders and hugely across the region, from US$1,740 in China in 2005, to US$4,460 in Russia, US$11,770 newts (72%) than it is among the frogs and toads (10%), a pattern mirrored in the Nearctic. in Saudi Arabia, US$27,900 in western Europe, and US$38,390 in Japan. Economic growth The most speciose genera in the region are Rana2 (83 species), Bufo2 (39 species), Paa (24 rates are very high in China (reaching 10% annually), and now averaging 6% in eastern species), Hynobius (24 species), Xenophrys (23 species) and Amolops (20 species). There Europe, Russia, and central Asia, but much lower (<3%) in western Europe and Japan. are eight monotypic genera endemic to the Palaearctic Realm, all of which are salamanders. The high economic growth rate in China, and high overall wealth in Europe, as well as high The 44 non-endemic genera in the Palaearctic include 37 frog genera (14 genera from Pachyhynobius shangchengensis (Vulner- human population densities, explain why damage to natural ecosystems has been so extensive in the Ranidae, nine from the Megophryidae, seven from the Rhacophoridae, four from the able) is a member of the Asian salamander the eastern and western parts of the region. In China, but in Europe and the Middle East to an even Microhylidae, and one each from the Bombinatoridae, Bufonidae and Hylidae) and seven Family Hynobiidae. It is known only from the greater extent, humans modified extensive areas of natural habitat over 1,000 years ago. High levels salamander genera (five from the Salamandridae, and one each from the Cryptobranchidae Dabieshan area in central China, and it lives of habitat modification are still ongoing in China and many other parts of the region. Conversely, in and the Hynobiidae). in slow-flowing hill streams in forested areas, the central and northern parts of the region, many ecosystems are still largely intact. As noted, 15 of the world’s 48 amphibian families (31%) occur in the Palaearctic, of where its larvae also develop. Over-harvesting which three are endemic: Discoglossidae, Pelobatidae, and Pelodytidae. The characteristics for human consumption is a major threat to of these families are provided in Chapter 1. this species. © Arnaud Jamin GLOBAL CONSERVATION STATUS Among the non-endemic families, the majority of Palaearctic species are in the Bufonidae, Megophryidae, Ranidae, Rhacophoridae, Hynobiidae and Salamandridae. Of the Palaearctic A total of 113 species (24%) of amphibian in the Palaearctic Realm is considered to be globally Bufonidae, all 39 species are in the widespread genus Bufo3. This family occurs through most Table 1. The number of Palaearctic amphib- threatened or Extinct (see Figure 1). This is significantly less than the global average of 33%1. The of the region, and 20 species (51%) are shared with other regions (mainly Indomalayan, but ians in each taxonomic Family present in also Afrotropical).