Cardoso Pedro, Crespo Luís C, Silva Isamberto, Borges Paulo Av, Boieiro Mário
Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland.
IUCN SSC Spider & Scorpion Specialist Group, Helsinki, Finland.
Biodivers Data J. 2017 Oct 18(5):e20810. doi: 10.3897/BDJ.5.e20810. eCollection 2017.
The North Atlantic archipelagos of Madeira and Selvagens present a unique biological diversity including, presently, 56 endemic spider species. Several recent projects provide valuable information on their distribution across most islands and habitats. To date, the only endemic spider assessed according to the IUCN Red List criteria is The objective of this paper is to assess all remaining endemic species and advise on possible future conservation actions critical for the survival of endangered species.
Seven species were found to have a continuing decline in either range or population size. Their decline can be mostly attributed to habitat destruction or degradation, invasive plant species that reduce quality of habitat, forest fires at high mountain regions and possible competition for resources from invasive congeners. The tetragnathid is considered as possibly extinct due to the suspected impact of a competing species. Although most endemic spiders from the Madeira and Selvagens archipelagos have relatively low extinction risk due to the good condition and protection of the laurisilva forests where many live, there are a number of species requiring urgent attention and protection measures. These include all cave and mountain-restricted species as well as those threatened by competing congeners or invasive plants. Extending current protected areas, restoring original habitats of threatened species and the control of invasive taxa should remain a priority for species survival.
马德拉群岛和塞尔瓦根斯群岛位于北大西洋，拥有独特的生物多样性，目前有56种特有蜘蛛物种。最近的几个项目提供了有关它们在大多数岛屿和栖息地分布的宝贵信息。迄今为止，根据世界自然保护联盟红色名录标准评估的唯一特有蜘蛛是……本文的目的是评估所有剩余的特有物种，并就对濒危物种生存至关重要的未来可能的保护行动提出建议。
发现有7个物种的分布范围或种群数量持续下降。它们的下降主要可归因于栖息地破坏或退化、降低栖息地质量的入侵植物物种、高山地区的森林火灾以及来自入侵同类物种的资源竞争。由于疑似受到竞争物种的影响，长脚蛛属物种被认为可能已经灭绝。尽管由于许多特有蜘蛛生活的月桂树林状况良好且受到保护，马德拉群岛和塞尔瓦根斯群岛的大多数特有蜘蛛灭绝风险相对较低，但仍有一些物种需要紧急关注和保护措施。这些物种包括所有洞穴和山区受限物种，以及那些受到竞争同类物种或入侵植物威胁的物种。扩大现有保护区、恢复受威胁物种的原始栖息地以及控制入侵类群仍应是物种生存的优先事项。
