Integrating host use and dispersal ability with species delimitation to unravel a cryptic radiation of photosynthetic sea slugs

Species delimitation models are important quantitative tools for facilitating the discovery of cryptic species and clarifying the boundaries between focal taxa. However, distinct evolutionary processes may promote diversification at different points in a radiation, complicating efforts to identify speciation processes and diagnostic characters. Moreover, traits like dispersal ability can have opposing effects on diversification rate versus population subdivision, which causes coalescent models to oversplit samples. In this study, we examined the effects of larval dispersal and host use on population structure and diversity in a Caribbean radiation of photosynthetic herbivores, sea slugs in the genus Elysia. We applied five species delimitation models (SDMs) to molecular datasets, and also performed phylogenetic analyses of evolutionary relationships and population-genetic structure within species. We further modeled ancestral use of host algae using Bayesian Inference methods. Datafiles..., , # Integrating host use and dispersal ability with species delimitation to unravel a cryptic radiation of photosynthetic sea slugs

Dataset DOI: [10.5061/dryad.0gb5mkmff](https://doi.org/10.5061/dryad.0gb5mkmff)

## Description of the data and file structure

Index and description of DRYAD supporting data and output files associated with the article Krug et al., “Integrating host use and dispersal ability with species delimitation to unravel a cryptic radiation of photosynthetic sea slugs”, ***Biological Journal of the Linnean Society*** (https:10.1093/biolinnean/blaf111).

### Files and variables

#### File: 1_7spp_collapsed_outgroups.nex

**Description:** Phylip-format input file for RaXML analysis containing collapsed COI haplotypes from candidate *Elysia* species (234 unique ingroup haplotypes) plus three related *Elysia* spp. as outgroups (3 additional haplotypes).

#### File: 2_7sppCOI.nex

**Description:** Nexus-format *BayesPhylogenies* input file containing the same 237 COI hapl...,