| Plants | 3,892 | 1,957 | 50.3 | | Mammals | 68 | 15 | 22.1 | | Birds | 226 | 12 | 5.3 | | Reptiles | 41 | 27 | 65.9 | | Amphibians | 41 | 29 | 70.7 | | Freshwater Fishes | 43 | 24 | 55.8 |
unique and threatened biodiversityThe Chilean Winter Rainfall-Valdivian Forests Hotspot represents the crossroads of two major floristic and faunistic regions: the Neotropical and ancient Gondwanan provinces. The influence of past geographical links between South America and other southern lands, such as Australia, is evident in the hotspot’s high plant endemism. Of the nearly 4,000 vascular plants found in this hotspot, about half are endemic. These numbers represent about three-quarters of all Chilean plant species and endemics in only 40 percent of the land area. Plant diversity in the winter-rainfall area is around 3,539 species (compared with the Valdivian Forests which support only around 1,284 species), of which 1,769 (50 percent) are endemic to that subunit. The Juan Fernández Islands have a flora comprised of 200 native species, as well as over 200 introduced species, many of which are natives of continental Chile. The isolation of these offshore islands causes high endemism in their native floras, with 62 percent endemism.The hotspot is home to three endemic plant families (Aextoxicaceae, Gomortegaceae and Lactoridaceae), and several monotypic endemic plant genera (Pitavia, Legrandia, and Jubaea). The ruil forest of coastal central Chile is an important refuge for the endemic trees Gomortega keule and Nothofagus alessandri. At present, it remains as a narrow strip only 100 kilometers long and is disappearing at the rate of eight percent each year as native forests are cleared for Monterey pine (Pinus radiata) plantations. Although not rich in species, the plant communities of the Valdivian Forests also include primitive Asteraceae species and representatives of the Andean family Calyceraceae, both thought to be remnants of ancient plant communities from the super continent Gondwanaland. They provide valuable windows into the evolutionary history of plants. Among other notable plant species in the hotspot are the araucaria trees (Araucaria araucana) and Chile's national flower, the copihue or Chile-bells (Lapageria rosea).
Characteristically, birds are not very well represented in this hotspot. The region's bird diversity includes just over 225 species. There are a dozen endemic bird species here, including three breeding species of petrel, and the region is considered a priority Endemic Bird Area by Birdlife International. The hotspot also has two monotypic endemic bird genera: Sephanoides, which is represented by the Juan Fernández firecrown (S. fernandensis, CR), confined to the Juan Fernández Islands, and the green-backed firecrown (S. sephaniodes), and Sylviorthorhynchus, which is represented by the Des Murs’ wiretail (S. desmursii), resticted toothe temperate forest in south-central Chile.
Mammal endemism is relatively low, with almost 70 species and only 15 endemics. There are, however, five endemic genera. The rodent genus Octodon comprises three species of degus, while the remaining four genera are all represented by single species: the Chilean climbing mouse (Irenomys tarsalis), the Chilean shrew opossum (Rhyncholestes raphanurus), the coruro (Spalacopus cyanus), and the monito del monte (Dromiciops gliroides, VU). The last-named species is not just the only genus in an endemic family, the Microbiotheriidae, but the only known representative of an entire order, the Microbiotheria (this is the only hotspot to host an endemic mammalian order). The species is known only in the proximity of Concepción south to Chiloé Island, south-central Chile, and in the mountains east of the Argentine border. One well-known endemic rodent species is the chinchilla (Chinchilla lanigera, VU), prized around the world for its soft, dense fur. Chinchillas have been hunted and trapped nearly to extinction in the wild, although they are widely bred in captivity. Darwin’s fox (Pseudalopex fulvipes, CR) exists in only two known populations, one in the forests of Chiloé Island and another in the coastal mountains of Naheulbuta National Park. Other notable mammals include the mountain vizcacha (Lagidium viscacia), a large, gregarious rodent that lives high in the upper reaches of the Andes; the pudu (Pudu puda, VU), the smallest South American deer, which lives at lower elevations and is declining rapidly as a result of habitat destruction, competition with livestock, and hunting; the Andean cat (Leopardus jacobita, EN); and two species of brown bats, the Atacama myotis (Myotis atacamensis, VU) and Chilean myotis (M. chiloensis), both restricted to this region. The endemic Juan Fernández fur seal (Arctocephalus philippii, VU) breeds on the Juan Fernández islands.
Endemism levels for both reptiles and amphibians are high. About two-thirds of the hotspot’s more than 40 reptile species are endemic. A large number of these species are lizards, found at mid-to-high elevations. The lizard genus Liolaemus accounts for three-quarters of the reptile species in the hotspot and, of these, two-thirds are endemic. Interestingly, there are only two representatives of the world's largest snake family, Colubridae, namely Chilean green racer (Philodryas chamissonis), which is endemic, and Chilean slender snake (Tachymenis chilensis); there are no terrestrial or freshwater turtles found here.
Around three-quarters of the more than 40 amphibian species in the hotspot are endemic. Additionally, one family (Rhinodermatidae) and five genera are endemic to the hotspot: Telmatobufo, with three species, all threatened; Rhinoderma, with two species; and Insuetophrynus, Caudiverbera, and Hylorina, each with a single species. Furthermore, this is one of the few hotspots with an endemic amphibian family (Rhinodermatidae), with Darwin’s frog (Rhinoderma darwini, VU) and the Chile Darwin’s frog (R. rufum, CR) among the most important flagship species for this region.
Although the hotspot has a relatively small fish fauna, with only just over 40 native species, it has a remarkable two endemic families: the mountain catfishes (Nematogenyidae) and the perch-like fishes of the genus Percilia (family Perciliidae). Nearly 20 percent of the region’s fish species are relicts of Gondwanan groups and are also found in southern Africa, Australia and New Zealand.
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© Michael and Patricia Fogden
This male Darwin's frog (Rhinoderma darwinii, VU) has just deposited froglets onto the ground from his vocal sac. Darwin's frog is endemic to the hotspot and inhabits the Mediterranean region and the southern temperate forests.
© Juan Carlos Muñoz/Still Pictures
The mountain vizcacha (Lagdium viscacia) is a large rodent in the chinchilla family that inhabits rocky outcrops in the high Andes mountains of central Chile.
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