Details

Autor(en) / Beteiligte

• Ortiz, David
• Pekár, Stano
• Bryjová, Anna

Titel

Gene flow assessment helps to distinguish strong genomic structure from speciation in an Iberian ant-eating spider

Ist Teil von

• Molecular phylogenetics and evolution, 2023-03, Vol.180, p.107682-107682, Article 107682

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2023

Quelle

MEDLINE

Beschreibungen/Notizen

• [Display omitted] •Zodarion alacre is composed of four well-defined genomic lineages.•Genomic species delimitation analyses recover these as different species.•However, substantial gene flow among lineages rejects complete speciation.•Z. alacre seems to have expanded from southern Portugal to central Spain. Although genomic data is boosting our understanding of evolution, we still lack a solid framework to perform reliable genome-based species delineation. This problem is especially critical in the case of phylogeographically structured organisms, with allopatric populations showing similar divergence patterns as species. Here, we assess the species limits and phylogeography of Zodarion alacre, an ant-eating spider widely distributed across the Iberian Peninsula. We first performed species delimitation based on genome-wide data and then validated these results using additional evidence. A commonly employed species delimitation strategy detected four distinct lineages with almost no admixture, which present allopatric distributions. These lineages showed ecological differentiation but no clear morphological differentiation, and evidence of introgression in a mitochondrial barcode. Phylogenomic networks found evidence of substantial gene flow between lineages. Finally, phylogeographic methods highlighted remarkable isolation by distance and detected evidence of range expansion from south-central Portugal to central-north Spain. We conclude that despite their deep genomic differentiation, the lineages of Z. alacre do not show evidence of complete speciation. Our results likely shed light on why Zodarion is among the most diversified spider genera despite its limited distribution and support the use of gene flow evidence to inform species boundaries.