Genomics Reveals the Origins of Historical Specimens.

Centuries of zoological studies have amassed billions of specimens in collections worldwide. Genomics of these specimens promises to reinvigorate biodiversity research. However, because DNA degrades with age in historical specimens, it is a challenge to obtain genomic data for them and analyze degraded genomes. We developed experimental and computational protocols to overcome these challenges and applied our methods to resolve a series of long-standing controversies involving a group of butterflies. We deduced the geographical origins of several historical specimens of uncertain provenance that are at the heart of these debates. Here, genomics tackles one of the greatest problems in zoology: countless old specimens that serve as irreplaceable embodiments of species concepts cannot be confidently assigned to extant species or population due to the lack of diagnostic morphological features and clear documentation of the collection locality. The ability to determine where they were collected will resolve many on-going disputes. More broadly, we show the utility of applying genomics to historical museum specimens to delineate the boundaries of species and populations, and to hypothesize about genotypic determinants of phenotypic traits.

Resolving two centuries of mistaken identity: Reinterpretation of Papilio marcus Fabricius, 1787 (Lepidoptera: Nymphalidae, Hesperiidae).

Here, we untangle an oversight surrounding the application of the name Papilio marcus Fabricius, 1787 (Hesperiidae: Hesperiinae), currently in Troyus Warren & Turland, 2012, which has eluded taxonomists for nearly two centuries. First, we note that P. marcus is a junior primary homonym of Papilio marcus Schaller, 1785, a species currently in Morpho Fabricius, 1807 (Nymphalidae: Satyrinae). Second, we designate a lectotype for P. marcus Fabricius, 1787, and recognize it as conspecific with Papilio phyllus Cramer, 1777, a species currently in Vettius Godman, 1901. Therefore, P. marcus is also a junior subjective synonym of V. phyllus (new synonym). Third, aided by genomic sequencing of the lectotype of Vettius phyllides Röber, 1925, we find that this species is not conspecific with V. phyllus and represents instead a valid species of Troyus Warren & Turland, 2012, so that the relative epithet, currently considered as a junior subjective synonym of P. marcus, has to be reappreciated as Troyus phyllides (reinstated status, new combination). Moreover, T. phyllides is apparently the species that has been misidentified as P. marcus since 1832. As a result of this study, the name P. marcus Fabricius nec Cramer falls in synonymy with P. phyllus (currently in Vettius), and the species currently known as T. marcus becomes Troyus phyllides.