Analysis of Endemism of World Arthropod Distribution data supports Biogeographic Regions and many established Subdivisions

JONATHAN LIRIA; SZUMIK, CLAUDIA; GOLOBOFF, PABLO

CLADISTICS (PRINT)

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2020

0748-3007

We analyzed 769,242occurrence records for 115,424 species of terrestrial arthropods, from threebiodiversity repositories (GBIF, NHM, and SpeciesLink), to test the use ofglobal-scale data points for quantitative assessments of areas of endemism. Thedata include Insecta (105,941 species), Arachnida (7,984 species), Myriapoda (1,229),and terrestrial crustaceans (270 Branchiopoda). The species were assigned to 14,543higher taxonomic groups because such groups often characterize larger areas ofendemism. Putative areas of endemism were visualized as sets of cellsdisplaying unique groups of species without the assumption of hierarchicalrelationships. Yet, the use of 10° grid cells recovered many large areasbroadly corresponding to Biogeographic Regions (Nearctic, Neotropical,Panamanian, Palearctic, Afrotropical, Australian, Oceanian and Oriental) albeitwith the limits poorly defined. An analysis of 5° grids resulted in 306 sets includedin the different Biogeographic Realms: Afrotropical, Australian, Madagascan, Neartic,Neotropical, Oceanian, Oriental, Paleartic, Saharo-Arabian and Sino-Japanese.The Panamanian Realm comprises 89 partly overlapping sets, crossing the Nearcticand Neotropical boundaries. A total of 7,338 species of Insecta were endemic tosome area, followed by Arachnida (412 spp), and 105 species in other clades rankedas ?classes?. Six sets were supported only by genera, except for Panamaniansets that were supported by genera and families. Many of the species in thedataset are included in IUCN red lists, but probably most of those havedistributions more restricted than global areas of endemism; only 102 appear asendemic to some area. The results show that data from global databases can beused to identify areas of endemism on a worldwide basis but ?due to theirincompleteness?only at a relatively coarse level. At the level of resolutioncurrently allowed by such databases, such global studies are only complementaryto studies where areas are subjectively determined by systematists (instead ofactual point records), or studies using point records in datasets for specifictaxonomic groups curated and compiled by specialists