Macroecological inferences on soil fauna through comparative niche modeling: The case of Hormogastridae (Annelida, Oligochaeta)

Ecological Niche Modeling (ENM) through MaxEnt and quantitative comparison techniques using ENMtools could facilitate ecological inferences in problematic soil dwelling taxa. Despite its ecological relevance in the Western Mediterranean basin, the ecology of the endemic family Hormogastridae (Annelida, Oligochaeta) is poorly known. Applying this comparative approach to the main clades of Hormogastridae would allow a better understanding of their ecological preferences and differences. One hundred twenty-four occurrence data belonging to four clades within this earthworm family were used as input to infer separate MaxEnt models, including seven predictor variables. Niche breadth, niche overlap and identity tests were calculated in ENMtools; a spatial Principal Components Analysis (sPCA) was performed to contrast with the realized niches. The highly suitable predicted ranges varied in their ability to reflect the known distribution of the clades. The different analyses pointed towards different ecological preferences and significant ecological divergence in the four above-mentioned clades. These results are an example of wide-scale ecological inferences for soil fauna made possible by this promising methodology, and show how ecological characterization of relevant taxonomic units could be a useful support for systematic revisions.