Lessons From a Museum's Cabinet: DNA Barcoding and Collections-Based Life Stage Associations Reveals a Hidden Diversity in the Puerto Rican Bank Paedomorphic Lycidae (Coleoptera: Elateroidea: Leptolycini)

The Leptolycini are a group of Lycidae endemic to the West Indies. Leptolycini adult females have been hypothesized to be extreme paedomorphic (i.e., larviform), however, females and larvae of the group are currently unknown. Here we provide the first association of adult male and immature life stages from the Puerto Rico using DNA barcoding, also collections-based associations and descriptions of immature Leptolycini and the first description of a paedomorphic female from the Virgin Islands. To carry out these life-stage associations we prepared an in-depth review of the Leptolycini fauna of the Puerto Rican bank (Puerto Rico and Virgin Islands). Several new taxa and taxonomic arrangements are proposed: Cessator crypticusnew species, Cessator tortolensisnew species, Cessator obrienorumnew species; Dracolycus chupacabranew genus and species, Dracolycus marshallinew species; Leptolycus falsoheterocornisnew species, and Leptolycus viensisnew species. Nanolycus gnomus Kazantsev is moved to Cessator gnomus (Kazantsev) new combination, rendering Nanolycus Kazantsev a new junior synonym of Cessator Kazantsev. The subgenus Baholycus Bocak is a new junior synonym of Leptolycus Leng and Mutchler. Leptolycus heterocornis var. flavicollis Leng and Mutchler is elevated to Leptolycus flavicollis Leng and Mutchler new status; Leptolycus (Leptolycus) albicauda Kazantsev is a new junior synonym of Leptolycus flavicollis Leng and Mutchler. An updated key to the adults and immature forms of Leptolycini from the Puerto Rican bank and a discussion on the importance of scientific collections in biodiversity studies is also provided.