Data from: Taking the discovery approach in integrative taxonomy: decrypting a complex of narrow-endemic Alpine harvestmen (Opiliones: Phalangiidae: Megabunus)

Species delimitation is fundamental for biological studies, yet precise
delimitation is not an easy task, and every involved approach has an
inherent failure rate. Integrative taxonomy, a method that merges multiple
lines of evidence, can profoundly contribute to reliable alpha taxonomy
and shed light on the processes behind speciation. In this study, we
explored and validated species limits in a group of closely related
Megabunus harvestmen (Eupnoi, Phalangiidae) endemic to the European Alps.
Without a priori species hypotheses, we used multiple sources of
inference, including mitochondrial and multilocus nuclear DNA,
morphometrics, and chemistry. The results of these discovery approaches
revealed morphological crypsis and multiple new species within two of the
five hitherto known species. Based on our analyses, we discussed the most
plausible evolutionary scenarios, invoked the most reasonable species
hypotheses, and validated the new species limits. Building upon the
achieved rigour, three new species, M. cryptobergomas Muster &
Wachter sp. nov., M. coelodonta Muster & Steiner sp. nov., and M.
lentipes Muster & Komposch sp. nov., are formally described. In
addition, we provide a dichotomous morphological key to the Megabunus
species of the Alps. Our work demonstrates the suitability of integrative,
discovery-based approaches in combination with validation approaches to
precisely characterise species and enabled us to implement nomenclatural
consequences for this genus.