The California Floristic province is a biodiversity hotspot. Understanding the phylogeographic patterns that exist in this diverse region is essential to understanding its evolution and for guiding conservation efforts. Calosaturnia is a charismatic silkmoth genus endemic to large portions of the region with three described species, C. mendocino, C. walterorum, and C. albofasciata. We sampled all three species from across their ranges, sequenced 1463 bp of mitochondrial COI and 1941 bp of nuclear DNA from three genes, and reconstructed phylogenetic relationships and estimated divergence times within the lineages. All three species show pronounced evidence of isolation and, in two cases, secondary reconnection. An unexpected monophyletic mtDNA lineage was found in the Central Coast region, in a region thought to represent an intergrade between C. mendocino and C. walterorum. Our genetic data also significantly revise previous hypotheses as to which species occur in which regions, suggesting that historical ecological changes around four Ma ago isolated some lineages, and a secondary isolation event two Ma ago led to isolation of populations both in the Central Coast region and the southern Sierra Nevada. Our results add to a currently under appreciated pattern suggesting that coastal Central California is not a transition zone between Northern and Southern California Floristic Province faunas but rather its own unique, periodically isolated, biogeographic region. They also suggest cryptic diversity may be present in many other currently unrecognized groups. Additional research should focus on this central California region because many species may be highly restricted in range and in need of conservation attention.

Sanger sequencing; see paper for further details

Data for: Phylogeography of an endemic California silkmoth genus suggests the importance of an unheralded central California province in generating regional endemic biodiversity

Supplemental_table_1.xlsx
Table with sample collecting information and genbank accession numbers for each marker

Calosaturnia_concatenated_IQtree.pdf
Maximum likelihood tree generated with IQ-TREE based on the concatenated mtDNA and nuDNA alignments

Calosaturnia_CAD_EF_WG_alignment.fas
Multiple sequence alignment file in FASTA format with the nuclear markers CAD, EF and WG

Calosaturnia_CAD_EF_WG_full_tree.pdf
The full maximum likelihood tree generated with IQ-TREE based on the nuDNA (published version has outgroups cropped)

Calosaturnia_COI5P3P_alignment.fas
Multiple sequence alignment file in FASTA format with the mitochondrial marker COI

Calosaturnia_COI5P3P_full_tree_IQTree.pdf
The full maximum likelihood tree generated with IQ-TREE based on the mtDNA (published version has outgroups cropped)

Calosaturnia_COI5P3P_full_tree_RevBayes.pdf
The full Bayesian timetree generated with the RevBayes analysis (published version has outgroups cropped)

Calosaturnia_revbayes_molclock.ipynb
Jupyter notebook with the script used for the RevBayes molecular clock analysis