COI Leray fragment of adult and juvenile spiders

Biodiversity loss is a major problem at the global scale, so bioinventories and monitoring samplings are essential to identify and tackle threats to biodiversity. Arthropods are usually misrepresented in these inventories, despite being the largest component of animal diversity. This is mainly due to the difficulty of identification in some arthropod groups, such as spiders, which can only be morphologically identified to species level at adult stages. Thus, juvenile spiders are usually discarded during sorting despite representing around half of the specimens, but the impact this has on community-level diversity estimates is still unknown.
Here, we use a metabarcoding approach to assess the contribution that juvenile stages of spiders collected across the Iberian Peninsula have on diversity estimates, and their effect on diversity patterns across communities. We also compare the proportion of reads and the abundance of each family in the samples to assess the quantitative power of meta..., For adult spiders:
Legs of spiders were used for DNA extraction (more information about the specimens in Crespo et al, 2018). Total genomic DNA was extracted using the REDExtract-N-Amp™ Tissue PCR Kit Protocol from Sigma-Aldrich, following the manufacturer’s protocol and performed in 96 well-plates. We amplified the mitochondrial cytochrome c oxidase (COI). The LCOI1490/ HCO2198 was the preferred combination of primers, while Nancy was used as a replacement for HCOI2198 and Ron as replacement for LCOI1490 (in that order). For problematic amplifications, we used the internal primers mlCOIintF/jgHCOI2198. The polymerase chain reaction (PCR) was performed in 96-well plates using 8 µl REDExtract-N-Amp™ PCR ReadyMix from Sigma-Aldrich, primers forward and reverse, 4 µl of diluted DNA and ultrapure, distilled water up to a total reaction volume of 20 µl. PCR products were cycle-sequenced in both directions at Macrogen Inc. (Seoul, South Korea). We trimmed the sequences to keep only the Leray ..., , # COI Leray fragment of adult and juvenile spiders

[https://doi.org/10.5061/dryad.z08kprrcv](https://doi.org/10.5061/dryad.z08kprrcv)

The dataset includes two fasta files, \"Adults.fasta\" and \"Juveniles.fasta\". The file \"Adults.fasta\" contains all the Cytochrome c Oxidase 1 (COI) sequences obtained from adult specimens, which were obtained by Sanger sequencing a variable number of legs. The \"Juveniles.fasta\" file contains all COI sequences obtained from metabarcoding analyses applied to bulk samples of juvenile specimens. All the reads obtained were clustered into MOTU's, which were taxonomically assigned to the deepest possible level.

## Description of the data and file structure

Both files are in fasta format. The headers of the Adults.fasta file include the individual code of the specimen (MD-); the number of reads that were artificially included in the analyses of each sequence (count=50000); the taxonomy identifier (taxid) of each species in NCBI; the order name and associated n...