Revisiting Colobura (Lepidoptera: Nymphalidae): Using integrative taxonomy to identify a new species, C. cryptica sp. nov., and revise geographic boundaries.

The Neotropical butterfly genus Colobura Billberg, 1820 (Nymphalidae) includes widespread, common and conspicuous species whose taxonomy one might expect to be well understood. Using integrative taxonomy-combining morphology (genitalia, larval traits, adult wing patterns, and UV reflectance), genome sequencing (mitochondrial barcodes, complete mitogenomes, and nuclear genomes), and life history data-we describe Colobura cryptica Sapkota, Orellana & Willmott sp. nov., a new species previously conflated with Colobura annulata. Key diagnostic morphological traits include: (1) a shorter third submarginal line on the ventral forewing that does not reach the pale cream transverse band, and (2) velvet-black larvae that lack yellow rings between segments or yellow spots at anterior edge of segments. Phylogenomic analyses resolved four distinct clades, with C. cryptica forming a genetically divergent lineage that is broadly sympatric with its sister species C. annulata. We further demonstrate a biogeographical split in C. dirce populations across the Andes and redefine the ranges of C. dirce wolcotti and C. dirce dirce. Genome sequencing showed that C. d. wolcotti, previously thought to be restricted to the Caribbean Islands, is also present in Central America and coastal Ecuador/northern Colombia west of the Andes, whereas C. d. dirce occurs only east of the Andes. This division corresponds with differences in ventral UV reflectance, which is strongly expressed in C. d. wolcotti but reduced in C. d. dirce. We conducted a preliminary investigation of UV-reflectance on the ventral wings and found evidence for differences across the four taxa, and we discuss the possibility of UV-mediated reproductive isolation that might have contributed to speciation in Colobura.