Biologia 70/5: 645—666, 2015 Section Zoology DOI: 10.1515/biolog-2015-0079 Red List of Czech spiders: 3rd edition, adjusted according to evidence-based national conservation priorities Milan Řezáč1*, Antonín Kůrka2, Vlastimil Růžička3 &PetrHeneberg4* 1Crop Research Institute, Biodiversity Lab, Drnovská 507,CZ-161 06 Prague, Czech Republic; e-mail:
[email protected] 217. listopadu 1173,CZ-293 02 Mladá Boleslav, Czech Republic 3Institute of Entomology, Biology Centre, Academy of Sciences of the Czech Republic, Branišovská 31,CZ-370 05 České Budějovice, Czech Republic 4Charles University in Prague, Third Faculty of Medicine, Ruská 87,CZ-100 00 Prague, Czech Republic; e-mail:
[email protected] Abstract: The knowledge on spiders of the Czech Republic has substantially improved since the second version of the national Red List was published, mainly due to large-scale field records and the establishment of an extensive, searchable electronic database of both retrospective and prospective records. Meanwhile, Central European spiders have undergone substantial changes in abundance and distribution. In this report, an updated Red List is presented and compared with the previous editions from 1992 and 2002, assessing all 879 spider species known to occur in the Czech Republic. For the first time, the abundance, area of occupancy and population trends were calculated for each of the species using the data from the Czech Arachnological Society recording scheme. Twenty-seven species (3% of the total) were classified as Regionally Extinct (RE), 92 (10%) as Critically Endangered, 115 (13%) as Endangered, 155 (18%) as Vulnerable, and 121 (14%) were classified as Least Concern species.