Museomics reveals the phylogenetic position of an enigmatic vertebrate family (Lophiiformes: Lophichthyidae)

Abstract

Lophichthys boschmai, the only member of the family Lophichthyidae, is an elusive lophiiform fish whose phylogenetic associations are debated. This family is among the last three vertebrate families lacking DNA sequence data, primarily due to the species rarity, lack of fresh material and challenges associated with sequencing formalin-treated museum specimens. In this study, we provide mitochondrial and nuclear DNA sequences obtained from two museum specimens of Lophichthys boschmai. Employing ancient DNA techniques, we successfully extracted and analyzed the degraded and fragmented DNA. Our findings, derived from both mitochondrial genomes and nuclear ultra-conserved elements (UCE), reveal the Lophichthyidae as sister lineage to Tathicarpidae within the Antennarioidei. This study showcases the use of whole-genome "shotgun" sequencing data from formalin-fixed museum specimens in the context of an available UCE dataset. Given the enhanced versatility in data reusability this approach offers, we suggest it should be a favored approach when studying rare specimens.