title: Discovery of Aspidytidae, a new family of aquatic Coleoptera.
abstract: The six extant aquatic families of Hydradephaga (Coleoptera) known so far represent a diverse group of beetles morphologically highly modified for life in the water. We report the discovery of a new genus with two species from South Africa and China, which differ greatly from all extant families, but resemble the Jurassic-Cretaceous dagger Liadytidae (the dagger symbol indicates that the taxa are known only as fossils). Based on a combined phylogenetic analysis of molecular and morphological data we erect a new family, Aspidytidae, which is the sister group of Dytiscidae plus Hygrobiidae. We propose a new scenario for the evolution of swimming behaviour in adephagan beetles, in which the transition into the aquatic environment is followed by complex and repeated changes in lifestyles, including the secondary complete loss of swimming ability in Aspidytidae.
authors.affiliation: Department of Entomology, The Natural History Museum, Cromwell Road, London SW7 5BD, UK. i.ribera@nhm.ac.uk
authors.forename: I
authors.initials: I
authors.lastname: Ribera
authors.forename: R G
authors.initials: RG
authors.lastname: Beutel
authors.forename: M
authors.initials: M
authors.lastname: Balke
authors.forename: A P
authors.initials: AP
authors.lastname: Vogler
mesh_terms: D000818:Animals; D005075:Biological Evolution; D002681:China; D001517:Coleoptera / Q000145:classification* / Q000235:genetics* / Q000502:physiology; D004275:DNA, Ribosomal / Q000032:analysis; D017753:Ecosystem; D005260:Female; D005618:Fresh Water; D008297:Male; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D009068:Movement; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013019:South Africa
chemical_list: D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D012337:RNA, Ribosomal, 18S