BackgroundThere is an increasing demand for databases including species trait information for biodiversity and community ecology studies. The existence of trait databases is useful for comparative studies within taxa or geographical regions, but there is low availability of databases for certain organisms. Here we present an open access functional trait database for spiders from Macaronesia and the Iberian Peninsula, recording several morphological and ecological traits related to the species life histories, microhabitat and trophic preferences.New informationWe present a database that includes 12 biological traits for 506 spider species present in natural forests of the Iberian Peninsula (Spain) and three Macaronesian archipelagoes (Azores, Madeira and Canary Islands). The functional trait database consists of two sections:individual-level data for six morphological traits (total body size, prosoma length, prosoma width, prosoma height, tibia I length and fang length), based on direct measurements of 2844 specimens of all spider species; andspecies-level aggregate data for 12 traits (same 6 morphological traits as in the previous section plus dispersal ability, vertical stratification, circadian activity, foraging strategy, trophic specialization and colonization status), based on either the average of the direct measurements or bibliographic searches.This functional trait database will serve as a data standard for currently ongoing analyses that require trait and functional diversity statistics.
An increasing number of ecological studies are incorporating functional traits of organisms to understand global patterns of biodiversity (Díaz et al. 2015), community assembly (Kraft et al. 2008) and ecosystem functioning (de Bello et al. 2010). Functional traits allow us to understand the ecological role of organisms in the community, based on their features and on how the organisms interact in the ecosystem (Nock et al. 2016). Thus, trait based studies allow for the assessment of ecosystem functioning by using species biological traits as a proxy for the functional characteristics of the community assemblage (de Bello et al. 2010). Changes in the functional composition of species assemblages can be related to losses of ecosystem function (Mouillot et al. 2013).
Functional trait databases can be potentially useful for many scientific fields, helping to address questions in systematics, biogeography, macroecology, macroevolution or community assembly. Trait databases are valuable in phylogenetic comparative studies used for the reconstruction of ancestral morphology (Harmon et al. 2010) and to understand how different traits (i.e. body size) have evolved across phylogenetic clades (Kuntner and Coddington 2019), or to link genes with functions or phenotypes (Edmunds et al. 2015). Furthermore, trait-based studies are beneficial in conservation, helping to detect global change impacts or to predict if certain traits are correlated to extinction risk (Chichorro et al. 2019), or even to species invasiveness potential (Nyberg and Wallentinus 2005). Trait variation at intra (Garamszegi and Møller 2010) and interspecific levels (Kazakou et al. 2014) are valuable in comparative approaches or community ecology (Bolnick et al. 2011).
As a measure of the diversity of species niches and their functions, Functional Diversity (FD) has been used to understand how species richness or diversity relates to ecosystem function (Petchey and Gaston 2002, McGill et al. 2006, Petchey and Gaston 2006). It is often seen as reflecting a mechanistic link between taxonomic diversity and ecological processes (Cadotte et al. 2011). Given its implications, the selection of traits to quantify FD must be made with caution. Selected traits should reflect the functioning of species in ecosystems and allow understanding of the connection between FD and the response variable of interest according to individual hypotheses (Nock et al. 2016).
Spiders are among the most diverse and abundant predators in all habitats worldwide, being one of the most species-rich invertebrate orders with more than 48,400 described species (World Spider Catalog 2020). Spiders have been used as models in many ecological and evolutionary studies, including functional diversity studies from global (Cardoso et al. 2011) to regional (Cardoso 2012) scales, and methodological advances in phylogenetic and functional diversity analyses (Cardoso et al. 2014). Under this same framework, we are now building a series of analyses that require trait and FD-based statistics, for which the current compilation of traits will serve as a data standard.
We here present a functional trait database of spiders, selecting morphological and ecological traits related to species life histories, microhabitat and trophic preferences, allowing us to characterize the ecological roles of spiders in biological communities and their use of biotic and abiotic resources.
Our database includes 12 biological traits related to morphology, dispersal ability, vertical stratification, circadian activity, foraging strategy and prey range for all Iberian (Spain) and Macaronesian (Azores, Madeira and Canary Islands) spiders collected during several projects (see funding details in the acknowledgements section). A total of 506 species are included (364 from the Iberian Peninsula, 31 from Azores, 42 from Madeira and 69 from Canary Islands), representing ca. 25% of all acaronesian and Iberian species. The data were collected directly from specimens (i.e. direct morphological measurements), from the field (i.e. vertical stratification and circadian activity), and from scientific publications (i.e. dispersal ability, foraging strategy and prey range).
Iberian Peninsula and Macaronesian archipelagoes. In the Iberian Peninsula, spider communities were sampled from white-oak (Quercus L.) woodlands across the Spanish National Parks Network: 4 plots in Picos de Europa, 2 plots in Ordesa and Monte Perdido, 2 plots in Aigüestortes i Estany de Sant Maurici, 2 plots in Monfragüe, 4 plots in Cabañeros and 2 plots in Sierra Nevada (Crespo et al. 2018). In the Macaronesian archipelagoes, spiders were collected from natural laurel forest distributed as follows: 6 plots in Pico and 10 plots in Terceira (Azores) (Malumbres-Olarte et al. 2019), 12 plots in Madeira (Malumbres-Olarte et al. 2020), 10 plots in Tenerife and 7 plots in La Gomera (Canary Islands). Morphological measurements were taken directly from all species of spiders collected using the standardized COBRA (Conservation Oriented Biodiversity Rapid Assessment) (Cardoso et al. 2009) sampling protocol.
Iberian Peninsula (Spain) and Macaronesian archipelagoes (Azores, Madeira and Canary Islands).
Araneae. The database contains 506 species, accounting for 39 families of spiders. Some morphospecies or cryptic species identified by DNA as different lineages (see Crespo et al. 2018) were also recorded. Taxonomic changes were checked and updated according to the World Spider Catalog (World Spider Catalog 2020).
This dataset contains six morphological traits, four ecological traits and two other traits related to origin and dispersal ability.
The database consists of two sections:
Morphological traits, vertical stratification and nocturnality were extracted from the samples whenever possible. The combination of sampling methods provides us with direct information on the vertical stratum preferred by the species, from lower to higher stratification: pitfall traps (ground-dwelling species), vegetation sweeping (low vegetation species), active aerial searching and foliage beating (arboreal species). The time of day when species were collected (diurnal vs. nocturnal sampling) provides information about their circadian activity, although this can be biased given the methods used and should be used with caution. Species collected only in pitfall traps did not have such data, with information being extracted from the literature or based on our own field experience instead.
For morphological data, specimens were selected randomly from the available field collections and the measurements were made using a binocular stereoscope. All measurements are given in millimeters (mm). Each morphological trait was measured, whenever possible, for 10 individuals of each species, 5 females and 5 males. For some species only one individual of each sex (the specimen with median body size) was selected for measuring morphological traits other than body size.
In the second section, aggregate data at species level were taken as the average (by sex and total average) of the previous measures for morphological data when available, or from the literature when no individuals of a species could be measured. Additionally, the minimum and maximum ranges of body length for each sex were included. For vertical stratification and circadian activity, we calculated an index based on the collection data or, if not available, using the literature or personal knowledge of species. Other measures were taken from the literature, or often from personal experience with the species in the field.
1. Morphological traits (continuous variables) in millimeters (mm):
2. Ecological traits:
3. Other traits:
The data reported in this paper are deposited in the Figshare repository at https://doi.org/10.6084/m9.figshare.8320004.v3
Detailed morphometric measurements dataset including all specimens (2844) of 506 spider species. Measurements in millimeters (mm). Abbreviations: NA: Not Applicable; CRBA: Animal Biodiversity Resource Center; DTP: Dalberto Teixeira Pombo Collection; DZUL: Department of Zoology, University of La Laguna; IPNA-CSIC: Instituto de Productos Naturales (CSIC); MZB: Museum of Zoology, Barcelona; UAc: University of Azores code; UB: University of Barcelona. Observations: (*) specimens whose body size (Total_body_length_mm) is obtained by the sum of cephalothorax plus abdomen; (**) for the columns Prosoma_length_mm and Prosoma_height_mm, measurements with two values separated by -, the first one does not take into account the prosoma protuberance and the second one does take it into account. All column headers (but species) are equivalent to Darwin Core archives from GBIF.
|Column label||Column description|
|catalogNumber||An unique individual code for each specimen record within the data set or collection|
|collectionID||An identifier for the collection or dataset from which the record was derived|
|institutionCode||The name (or acronym) in use by the institution having custody of the object(s) or information referred to in the record|
|collectionCode||The name, acronym, code, or initialism identifying the collection or data set from which the record was derived|
|stateProvince||Province where the specimen was collected|
|county||County where the specimen was collected|
|locality||Locality where the specimen was collected|
|Total_body_length_mm||Total body length|
|Prosoma_length_mm||Maximum carapace length (without the chelicerae)|
|Prosoma_width_mm||Maximum carapace width|
|Prosoma_height_mm||Maximum carapace height (in lateral view)|
|Tibia_I_length_mm||Retrolateral length of the first tibia|
|Fang_length_mm||Maximum chelicerae fang length|
|Observations||Special record observations|
Summary of morphometric and ecological traits for 506 spider species. Abbreviations: (*) data taken from bibliography, specified in "Citation" column; (§) data from similar species/genera; #N/D: no associated code; NA: not applicable.
|Column label||Column description|
|species_Lsid||Life Science Identifier from the World Spider Catalog|
|Coloniz_AZO||Species origin for Azores|
|Coloniz_MAD||Species origin for Madeira|
|Coloniz_CAN||Species origin for Canary Islands|
|Body_length_min_f_mm||Minimum body length female|
|Body_length_max_f_mm||Maximum body length female|
|Body_length_min_m_mm||Minimum body length male|
|Body_length_max_m_mm||Maximum body length male|
|Body_length_avg_f_mm||Average body length female|
|Body_length_avg_m_mm||Average body length male|
|Body_length_avg_mm||Average body length|
|Prosoma_length_f_mm||Average carapace length female|
|Prosoma_length_m_mm||Average carapace length male|
|Prosoma_length_avg_mm||Average of carapace length|
|Prosoma_width_f_mm||Average carapace width female|
|Prosoma_width_m_mm||Average carapace width male|
|Prosoma_width_avg_mm||Average of carapace width|
|Prosoma_height_f_mm||Average carapace height female|
|Prosoma_height_m_mm||Average carapace height male|
|Prosoma_height_avg_mm||Average of carapace height|
|Tibia_I_length_f_mm||Average of retrolateral length of the first tibia female|
|Tibia_I_length_m_mm||Average of retrolateral length of the first tibia male|
|Tibia_I_length_avg_mm||Average of retrolateral length of the first tibia|
|Fang_length_f_mm||Average chelicerae fang length female|
|Fang_length_m_mm||Average chelicerae fang length male|
|Fang_length_avg_mm||Average of chelicerae fang length|
|Citation||Bibliography from where some measurements were taken if specimens were not available|
|Dispersal||Dispersal ability as (F)requent, (O)ccasional or (R)are ballooners|
|Verticality||Vertical stratification (from 0 - epigean to 1 - arboreal)|
|Nocturnality||Circadian activity (from 0 - diurnal to 1 - nocturnal)|
|Capture_web||Binary (web used for capturing prey)|
|Sensing_web||Binary (web used to detect prey)|
|No_web||Binary (no web used for hunting)|
|Tube_web||Binary (tube-shaped web)|
|Sheet_web||Binary (sheet-shaped web)|
|Space_web||Binary (space, tridimensional-shaped web)|
|Orb_web||Binary (orb-shaped web)|
|Ambush_hunter||Binary (hunt by ambushing prey)|
|Active_hunter||Binary (hunt actively)|
|Trophic specialization||Prey range (stenophagous or euriphagous)|
|Observations||Special record observations|
This study was supported by the project BIODIV ISLAND-CONT (Biodiversity drivers on islands and continents – 706482) funded by Marie Sklodowska-Curie Individual Fellowships (H2020-MSCA-IF-2015) to the first author NMH. The research was additionally funded by three other projects that provided the material collected for the database:
Additional support was provided by grant 2017SGR83 from the Catalan Government to MA. PB and PC are supported by AZORESBIOPORTAL–PORBIOTA (ACORES-01-0145-FEDER-000072) for the development of Functional Traits for Azorean arthropods. MD is supported by an APIF PhD fellowship from the University of Barcelona. We also thank Rutger Vos and Martin Ramirez for their valuable comments that greatly helped to improve the quality of this paper.
CR, MD, SF and IS measured the specimens. PC collected information about ecological traits at genus level. NMH wrote the manuscript with support from PC. CR made the tables. All authors commented on different versions of the manuscript.