The discovery of Iberobaeniidae (Coleoptera: Elateroidea): a new family of beetles from Spain, with immatures detected by environmental DNA sequencing

On the nomenclatural status of type genera in Coleoptera (Insecta)

More than 4700 nominal family-group names (including names for fossils and ichnotaxa) are nomenclaturally available in the order Coleoptera. Since each family-group name is based on the concept of its type genus, we argue that the stability of names used for the classification of beetles depends on accurate nomenclatural data for each type genus. Following a review of taxonomic literature, with a focus on works that potentially contain type species designations, we provide a synthesis of nomenclatural data associated with the type genus of each nomenclaturally available family-group name in Coleoptera. For each type genus the author(s), year of publication, and page number are given as well as its current status (i.e., whether treated as valid or not) and current classification. Information about the type species of each type genus and the type species fixation (i.e., fixed originally or subsequently, and if subsequently, by whom) is also given. The original spelling of the family-group name that is based on each type genus is included, with its author(s), year, and stem. We append a list of nomenclaturally available family-group names presented in a classification scheme. Because of the importance of the Principle of Priority in zoological nomenclature, we provide information on the date of publication of the references cited in this work, when known. Several nomenclatural issues emerged during the course of this work. We therefore appeal to the community of coleopterists to submit applications to the International Commission on Zoological Nomenclature (henceforth "Commission") in order to permanently resolve some of the problems outlined here. The following changes of authorship for type genera are implemented here (these changes do not affect the concept of each type genus): CHRYSOMELIDAE: Fulcidax Crotch, 1870 (previously credited to "Clavareau, 1913"); CICINDELIDAE: Euprosopus W.S. MacLeay, 1825 (previously credited to "Dejean, 1825"); COCCINELLIDAE: Alesia Reiche, 1848 (previously credited to "Mulsant, 1850"); CURCULIONIDAE: Arachnopus Boisduval, 1835 (previously credited to "Guérin-Méneville, 1838"); ELATERIDAE: Thylacosternus Gemminger, 1869 (previously credited to "Bonvouloir, 1871"); EUCNEMIDAE: Arrhipis Gemminger, 1869 (previously credited to "Bonvouloir, 1871"), Mesogenus Gemminger, 1869 (previously credited to "Bonvouloir, 1871"); LUCANIDAE: Sinodendron Hellwig, 1791 (previously credited to "Hellwig, 1792"); PASSALIDAE: Neleides Harold, 1868 (previously credited to "Kaup, 1869"), Neleus Harold, 1868 (previously credited to "Kaup, 1869"), Pertinax Harold, 1868 (previously credited to "Kaup, 1869"), Petrejus Harold, 1868 (previously credited to "Kaup, 1869"), Undulifer Harold, 1868 (previously credited to "Kaup, 1869"), Vatinius Harold, 1868 (previously credited to "Kaup, 1869"); PTINIDAE: Mezium Leach, 1819 (previously credited to "Curtis, 1828"); PYROCHROIDAE: Agnathus Germar, 1818 (previously credited to "Germar, 1825"); SCARABAEIDAE: Eucranium Dejean, 1833 (previously "Brullé, 1838"). The following changes of type species were implemented following the discovery of older type species fixations (these changes do not pose a threat to nomenclatural stability): BOLBOCERATIDAE: Bolbocerusbocchus Erichson, 1841 for Bolbelasmus Boucomont, 1911 (previously Bolbocerasgallicum Mulsant, 1842); BUPRESTIDAE: Stigmoderaguerinii Hope, 1843 for Neocuris Saunders, 1868 (previously Anthaxiafortnumi Hope, 1846), Stigmoderaperoni Laporte & Gory, 1837 for Curis Laporte & Gory, 1837 (previously Buprestiscaloptera Boisduval, 1835); CARABIDAE: Carabuselatus Fabricius, 1801 for Molops Bonelli, 1810 (previously Carabusterricola Herbst, 1784 sensu Fabricius, 1792); CERAMBYCIDAE: Prionuspalmatus Fabricius, 1792 for Macrotoma Audinet-Serville, 1832 (previously Prionusserripes Fabricius, 1781); CHRYSOMELIDAE: Donaciaequiseti Fabricius, 1798 for Haemonia Dejean, 1821 (previously Donaciazosterae Fabricius, 1801), Eumolpusruber Latreille, 1807 for Euryope Dalman, 1824 (previously Cryptocephalusrubrifrons Fabricius, 1787), Galerucaaffinis Paykull, 1799 for Psylliodes Latreille, 1829 (previously Chrysomelachrysocephala Linnaeus, 1758); COCCINELLIDAE: Dermestesrufus Herbst, 1783 for Coccidula Kugelann, 1798 (previously Chrysomelascutellata Herbst, 1783); CRYPTOPHAGIDAE: Ipscaricis G.-A. Olivier, 1790 for Telmatophilus Heer, 1841 (previously Cryptophagustyphae Fallén, 1802), Silphaevanescens Marsham, 1802 for Atomaria Stephens, 1829 (previously Dermestesnigripennis Paykull, 1798); CURCULIONIDAE: Bostrichuscinereus Herbst, 1794 for Crypturgus Erichson, 1836 (previously Bostrichuspusillus Gyllenhal, 1813); DERMESTIDAE: Dermestestrifasciatus Fabricius, 1787 for Attagenus Latreille, 1802 (previously Dermestespellio Linnaeus, 1758); ELATERIDAE: Elatersulcatus Fabricius, 1777 for Chalcolepidius Eschscholtz, 1829 (previously Chalcolepidiuszonatus Eschscholtz, 1829); ENDOMYCHIDAE: Endomychusrufitarsis Chevrolat, 1835 for Epipocus Chevrolat, 1836 (previously Endomychustibialis Guérin-Méneville, 1834); EROTYLIDAE: Ipshumeralis Fabricius, 1787 for Dacne Latreille, 1797 (previously Dermestesbipustulatus Thunberg, 1781); EUCNEMIDAE: Fornaxaustrocaledonicus Perroud & Montrouzier, 1865 for Mesogenus Gemminger, 1869 (previously Mesogenusmellyi Bonvouloir, 1871); GLAPHYRIDAE: Melolonthaserratulae Fabricius, 1792 for Glaphyrus Latreille, 1802 (previously Scarabaeusmaurus Linnaeus, 1758); HISTERIDAE: Histerstriatus Forster, 1771 for Onthophilus Leach, 1817 (previously Histersulcatus Moll, 1784); LAMPYRIDAE: Ototretafornicata E. Olivier, 1900 for Ototreta E. Olivier, 1900 (previously Ototretaweyersi E. Olivier, 1900); LUCANIDAE: Lucanuscancroides Fabricius, 1787 for Lissotes Westwood, 1855 (previously Lissotesmenalcas Westwood, 1855); MELANDRYIDAE: Nothusclavipes G.-A. Olivier, 1812 for Nothus G.-A. Olivier, 1812 (previously Nothuspraeustus G.-A. Olivier, 1812); MELYRIDAE: Lagriaater Fabricius, 1787 for Enicopus Stephens, 1830 (previously Dermesteshirtus Linnaeus, 1767); NITIDULIDAE: Sphaeridiumluteum Fabricius, 1787 for Cychramus Kugelann, 1794 (previously Strongylusquadripunctatus Herbst, 1792); OEDEMERIDAE: Helopslaevis Fabricius, 1787 for Ditylus Fischer, 1817 (previously Ditylushelopioides Fischer, 1817 [sic]); PHALACRIDAE: Sphaeridiumaeneum Fabricius, 1792 for Olibrus Erichson, 1845 (previously Sphaeridiumbicolor Fabricius, 1792); RHIPICERIDAE: Sandalusniger Knoch, 1801 for Sandalus Knoch, 1801 (previously Sandaluspetrophya Knoch, 1801); SCARABAEIDAE: Cetoniaclathrata G.-A. Olivier, 1792 for Inca Lepeletier & Audinet-Serville, 1828 (previously Cetoniaynca Weber, 1801); Gnathoceravitticollis W. Kirby, 1825 for Gnathocera W. Kirby, 1825 (previously Gnathoceraimmaculata W. Kirby, 1825); Melolonthavillosula Illiger, 1803 for Chasmatopterus Dejean, 1821 (previously Melolonthahirtula Illiger, 1803); STAPHYLINIDAE: Staphylinuspolitus Linnaeus, 1758 for Philonthus Stephens, 1829 (previously Staphylinussplendens Fabricius, 1792); ZOPHERIDAE: Hispamutica Linnaeus, 1767 for Orthocerus Latreille, 1797 (previously Tenebriohirticornis DeGeer, 1775). The discovery of type species fixations that are older than those currently accepted pose a threat to nomenclatural stability (an application to the Commission is necessary to address each problem): CANTHARIDAE: Malthinus Latreille, 1805, Malthodes Kiesenwetter, 1852; CARABIDAE: Bradycellus Erichson, 1837, Chlaenius Bonelli, 1810, Harpalus Latreille, 1802, Lebia Latreille, 1802, Pheropsophus Solier, 1834, Trechus Clairville, 1806; CERAMBYCIDAE: Callichroma Latreille, 1816, Callidium Fabricius, 1775, Cerasphorus Audinet-Serville, 1834, Dorcadion Dalman, 1817, Leptura Linnaeus, 1758, Mesosa Latreille, 1829, Plectromerus Haldeman, 1847; CHRYSOMELIDAE: Amblycerus Thunberg, 1815, Chaetocnema Stephens, 1831, Chlamys Knoch, 1801, Monomacra Chevrolat, 1836, Phratora Chevrolat, 1836, Stylosomus Suffrian, 1847; COLONIDAE: Colon Herbst, 1797; CURCULIONIDAE: Cryphalus Erichson, 1836, Lepyrus Germar, 1817; ELATERIDAE: Adelocera Latreille, 1829, Beliophorus Eschscholtz, 1829; ENDOMYCHIDAE: Amphisternus Germar, 1843, Dapsa Latreille, 1829; GLAPHYRIDAE: Anthypna Eschscholtz, 1818; HISTERIDAE: Hololepta Paykull, 1811, Trypanaeus Eschscholtz, 1829; LEIODIDAE: Anisotoma Panzer, 1796, Camiarus Sharp, 1878, Choleva Latreille, 1797; LYCIDAE: Calopteron Laporte, 1838, Dictyoptera Latreille, 1829; MELOIDAE: Epicauta Dejean, 1834; NITIDULIDAE: Strongylus Herbst, 1792; SCARABAEIDAE: Anisoplia Schönherr, 1817, Anticheira Eschscholtz, 1818, Cyclocephala Dejean, 1821, Glycyphana Burmeister, 1842, Omaloplia Schönherr, 1817, Oniticellus Dejean, 1821, Parachilia Burmeister, 1842, Xylotrupes Hope, 1837; STAPHYLINIDAE: Batrisus Aubé, 1833, Phloeonomus Heer, 1840, Silpha Linnaeus, 1758; TENEBRIONIDAE: Bolitophagus Illiger, 1798, Mycetochara Guérin-Méneville, 1827. Type species are fixed for the following nominal genera: ANTHRIBIDAE: Decataphanesgracilis Labram & Imhoff, 1840 for Decataphanes Labram & Imhoff, 1840; CARABIDAE: Feroniaerratica Dejean, 1828 for Loxandrus J.L. LeConte, 1853; CERAMBYCIDAE: Tmesisternusoblongus Boisduval, 1835 for Icthyosoma Boisduval, 1835; CHRYSOMELIDAE: Brachydactylaannulipes Pic, 1913 for Pseudocrioceris Pic, 1916, Cassidaviridis Linnaeus, 1758 for Evaspistes Gistel, 1856, Ocnosceliscyanoptera Erichson, 1847 for Ocnoscelis Erichson, 1847, Promecothecapetelii Guérin-Méneville, 1840 for Promecotheca Guérin- Méneville, 1840; CLERIDAE: Attelabusmollis Linnaeus, 1758 for Dendroplanetes Gistel, 1856; CORYLOPHIDAE: Corylophusmarginicollis J.L. LeConte, 1852 for Corylophodes A. Matthews, 1885; CURCULIONIDAE: Hoplorhinusmelanocephalus Chevrolat, 1878 for Hoplorhinus Chevrolat, 1878; Sonnetiusbinarius Casey, 1922 for Sonnetius Casey, 1922; ELATERIDAE: Pyrophorusmelanoxanthus Candèze, 1865 for Alampes Champion, 1896; PHYCOSECIDAE: Phycosecislitoralis Pascoe, 1875 for Phycosecis Pascoe, 1875; PTILODACTYLIDAE: Aploglossasallei Guérin-Méneville, 1849 for Aploglossa Guérin-Méneville, 1849, Coloboderaovata Klug, 1837 for Colobodera Klug, 1837; PTINIDAE: Dryophilusanobioides Chevrolat, 1832 for Dryobia Gistel, 1856; SCARABAEIDAE: Achloahelvola Erichson, 1840 for Achloa Erichson, 1840, Camentaobesa Burmeister, 1855 for Camenta Erichson, 1847, Pinotustalaus Erichson, 1847 for Pinotus Erichson, 1847, Psilonychusecklonii Burmeister, 1855 for Psilonychus Burmeister, 1855. New replacement name: CERAMBYCIDAE: Basorus Bouchard & Bousquet, nom. nov. for Sobarus Harold, 1879. New status: CARABIDAE: KRYZHANOVSKIANINI Deuve, 2020, stat. nov. is given the rank of tribe instead of subfamily since our classification uses the rank of subfamily for PAUSSINAE rather than family rank; CERAMBYCIDAE: Amymoma Pascoe, 1866, stat. nov. is used as valid over Neoamymoma Marinoni, 1977, Holopterus Blanchard, 1851, stat. nov. is used as valid over Proholopterus Monné, 2012; CURCULIONIDAE: Phytophilus Schönherr, 1835, stat. nov. is used as valid over the unnecessary new replacement name Synophthalmus Lacordaire, 1863; EUCNEMIDAE: Nematodinus Lea, 1919, stat. nov. is used as valid instead of Arrhipis Gemminger, 1869, which is a junior homonym. Details regarding additional nomenclatural issues that still need to be resolved are included in the entry for each of these type genera: BOSTRICHIDAE: Lyctus Fabricius, 1792; BRENTIDAE: Trachelizus Dejean, 1834; BUPRESTIDAE: Pristiptera Dejean, 1833; CANTHARIDAE: Chauliognathus Hentz, 1830, Telephorus Schäffer, 1766; CARABIDAE: Calathus Bonelli, 1810, Cosnania Dejean, 1821, Dicrochile Guérin-Méneville, 1847, Epactius D.H. Schneider, 1791, Merismoderus Westwood, 1847, Polyhirma Chaudoir, 1850, Solenogenys Westwood, 1860, Zabrus Clairville, 1806; CERAMBYCIDAE: Ancita J. Thomson, 1864, Compsocerus Audinet-Serville, 1834, Dorcadodium Gistel, 1856, Glenea Newman, 1842; Hesperophanes Dejean, 1835, Neoclytus J. Thomson, 1860, Phymasterna Laporte, 1840, Tetrops Stephens, 1829, Zygocera Erichson, 1842; CHRYSOMELIDAE: Acanthoscelides Schilsky, 1905, Corynodes Hope, 1841, Edusella Chapuis, 1874; Hemisphaerota Chevrolat, 1836; Physonota Boheman, 1854, Porphyraspis Hope, 1841; CLERIDAE: Dermestoides Schäffer, 1777; COCCINELLIDAE: Hippodamia Chevrolat, 1836, Myzia Mulsant, 1846, Platynaspis L. Redtenbacher, 1843; CURCULIONIDAE: Coeliodes Schönherr, 1837, Cryptoderma Ritsema, 1885, Deporaus Leach, 1819, Epistrophus Kirsch, 1869, Geonemus Schönherr, 1833, Hylastes Erichson, 1836; DYTISCIDAE: Deronectes Sharp, 1882, Platynectes Régimbart, 1879; EUCNEMIDAE: Dirhagus Latreille, 1834; HYBOSORIDAE: Ceratocanthus A. White, 1842; HYDROPHILIDAE: Cyclonotum Erichson, 1837; LAMPYRIDAE: Luciola Laporte, 1833; LEIODIDAE: Ptomaphagus Hellwig, 1795; LUCANIDAE: Leptinopterus Hope, 1838; LYCIDAE: Cladophorus Guérin-Méneville, 1830, Mimolibnetis Kazantsev, 2000; MELOIDAE: Mylabris Fabricius, 1775; NITIDULIDAE: Meligethes Stephens, 1829; PTILODACTYLIDAE: Daemon Laporte, 1838; SCARABAEIDAE: Allidiostoma Arrow, 1940, Heterochelus Burmeister, 1844, Liatongus Reitter, 1892, Lomaptera Gory & Percheron, 1833, Megaceras Hope, 1837, Stenotarsia Burmeister, 1842; STAPHYLINIDAE: Actocharis Fauvel, 1871, Aleochara Gravenhorst, 1802; STENOTRACHELIDAE: Stenotrachelus Berthold, 1827; TENEBRIONIDAE: Cryptochile Latreille, 1828, Heliopates Dejean, 1834, Helops Fabricius, 1775. First Reviser actions deciding the correct original spelling: CARABIDAE: Aristochroodes Marcilhac, 1993 (not Aritochroodes); CERAMBYCIDAE: Dorcadodium Gistel, 1856 (not Dorcadodion), EVODININI Zamoroka, 2022 (not EVODINIINI); CHRYSOMELIDAE: Caryopemon Jekel, 1855 (not Carpopemon), Decarthrocera Laboissière, 1937 (not Decarthrocerina); CICINDELIDAE: Odontocheila Laporte, 1834 (not Odontacheila); CLERIDAE: CORMODINA Bartlett, 2021 (not CORMODIINA), Orthopleura Spinola, 1845 (not Orthoplevra, not Orthopleuva); CURCULIONIDAE: Arachnobas Boisduval, 1835 (not Arachnopus), Palaeocryptorhynchus Poinar, 2009 (not Palaeocryptorhynus); DYTISCIDAE: Ambarticus Yang et al., 2019 and AMBARTICINI Yang et al., 2019 (not Ambraticus, not AMBRATICINI); LAMPYRIDAE: Megalophthalmus G.R. Gray, 1831 (not Megolophthalmus, not Megalopthalmus); SCARABAEIDAE: Mentophilus Laporte, 1840 (not Mintophilus, not Minthophilus), Pseudadoretusdilutellus Semenov, 1889 (not P.ditutellus). While the correct identification of the type species is assumed, in some cases evidence suggests that species were misidentified when they were fixed as the type of a particular nominal genus. Following the requirements of Article 70.3.2 of the International Code of Zoological Nomenclature we hereby fix the following type species (which in each case is the taxonomic species actually involved in the misidentification): ATTELABIDAE: Rhynchitescavifrons Gyllenhal, 1833 for Lasiorhynchites Jekel, 1860; BOSTRICHIDAE: Ligniperdaterebrans Pallas, 1772 for Apate Fabricius, 1775; BRENTIDAE: Ceocephalusappendiculatus Boheman, 1833 for Uroptera Berthold, 1827; BUPRESTIDAE: Buprestisundecimmaculata Herbst, 1784 for Ptosima Dejean, 1833; CARABIDAE: Amaralunicollis Schiødte, 1837 for Amara Bonelli, 1810, Buprestisconnexus Geoffroy, 1785 for Polistichus Bonelli, 1810, Carabusatrorufus Strøm, 1768 for Patrobus Dejean, 1821, Carabusgigas Creutzer, 1799 for Procerus Dejean, 1821, Carabusteutonus Schrank, 1781 for Stenolophus Dejean, 1821, Carenumbonellii Westwood, 1842 for Carenum Bonelli, 1813, Scaritespicipes G.-A. Olivier, 1795 for Acinopus Dejean, 1821, Trigonotomaindica Brullé, 1834 for Trigonotoma Dejean, 1828; CERAMBYCIDAE: Cerambyxlusitanus Linnaeus, 1767 for Exocentrus Dejean, 1835, Clytussupernotatus Say, 1824 for Psenocerus J.L. LeConte, 1852; CICINDELIDAE: Ctenostomajekelii Chevrolat, 1858 for Ctenostoma Klug, 1821; CURCULIONIDAE: Cnemogonuslecontei Dietz, 1896 for Cnemogonus J.L. LeConte, 1876; Phloeophagusturbatus Schönherr, 1845 for Phloeophagus Schönherr, 1838; GEOTRUPIDAE: Lucanusapterus Laxmann, 1770 for Lethrus Scopoli, 1777; HISTERIDAE: Histerrugiceps Duftschmid, 1805 for Hypocaccus C.G. Thomson, 1867; HYBOSORIDAE: Hybosorusilligeri Reiche, 1853 for Hybosorus W.S. MacLeay, 1819; HYDROPHILIDAE: Hydrophilusmelanocephalus G.-A. Olivier, 1793 for Enochrus C.G. Thomson, 1859; MYCETAEIDAE: Dermestessubterraneus Fabricius, 1801 for Mycetaea Stephens, 1829; SCARABAEIDAE: Aulaciumcarinatum Reiche, 1841 for Mentophilus Laporte, 1840, Phanaeusvindex W.S. MacLeay, 1819 for Phanaeus W.S. MacLeay, 1819, Ptinusgermanus Linnaeus, 1767 for Rhyssemus Mulsant, 1842, Scarabaeuslatipes Guérin-Méneville, 1838 for Cheiroplatys Hope, 1837; STAPHYLINIDAE: Scydmaenustarsatus P.W.J. Müller & Kunze, 1822 for Scydmaenus Latreille, 1802. New synonyms: CERAMBYCIDAE: CARILIINI Zamoroka, 2022, syn. nov. of ACMAEOPINI Della Beffa, 1915, DOLOCERINI Özdikmen, 2016, syn. nov. of BRACHYPTEROMINI Sama, 2008, PELOSSINI Tavakilian, 2013, syn. nov. of LYGRINI Sama, 2008, PROHOLOPTERINI Monné, 2012, syn. nov. of HOLOPTERINI Lacordaire, 1868.

Eocene aposematic patterns persist in modern European Lycidae beetles despite the absence of co-mimics

Ancient aposematic signals might have evolved under different ecological circumstances. Using European Cenozoic amber and phylogenetic reconstruction, we evaluated the evolution of net-winged beetle aposematism. We describe Priabonian Hiekeolycus winkleri sp. nov. from Baltic amber, review known fossil species, and suggest earlier high diversity and morphological conservativeness of European Lycidae since the Eocene. We hypothesize the presence of red and black/red aposematic patterns in Eocene Europe. The analyses suggest the Oligocene to Miocene dispersal of additional species from East Asia and their advergence to autochthonous patterns. Recently dispersed lycids have retained similarities with their East Asian relatives. Net-winged beetles are rare in Europe after the Quaternary climatic oscillations, and we hypothesize a currently relaxed selection for shared aposematic signals. Neophobia, and eventually inborn rejection of brightly colored prey, putatively preserved ancient aposematism under changing conditions. Evidence from paleontology and phylogenetics can provide insight into the long-term persistence of old adaptations under changing conditions.

Rhagophthalmidae Olivier, 1907 (Coleoptera, Elateroidea): described genera and species, current problems, and prospects for the bioluminescent and paedomorphic beetle lineage

Rhagophthalmidae are a small beetle family known from the eastern Palaearctic and Oriental realms. Rhagophthalmidae are closely related to railroad worms (Phengodidae) and fireflies (Lampyridae) with which they share highly modified paedomorphic females and the ability to emit light. Currently, Rhagophthalmidae include 66 species classified in the following 12 genera: Bicladodrilus Pic, 1921 (two spp.), Bicladum Pic, 1921 (two spp.), Dioptoma Pascoe, 1860 (two spp.), Diplocladon Gorham, 1883 (two spp.), Dodecatoma Westwood, 1849 (eight spp.), Falsophrixothrix Pic, 1937 (six spp.), Haplocladon Gorham, 1883 (two spp.), Menghuoius Kawashima, 2000 (three spp.), Mimoochotyra Pic, 1937 (one sp.), Monodrilus Pic, 1921 (two spp. in two subgenera), Pseudothilmanus Pic, 1918 (two spp.), and Rhagophthalmus Motschulsky, 1854 (34 spp.). The replacement name Haplocladongorhami Kundrata, nom. nov. is proposed for Diplocladonhasseltii Gorham, 1883b (described in subgenus Haplocladon) which is preoccupied by Diplocladonhasseltii Gorham, 1883a. The genus Reductodrilus Pic, 1943 is tentatively placed in Lampyridae: Ototretinae. Lectotypes are designated for Pseudothilmanusalatus Pic, 1918 and P.marginalis Pic, 1918. Interestingly, in the eastern part of their distribution, Rhagophthalmidae have remained within the boundaries of the Sunda Shelf and the Philippines demarcated by the Wallace Line, which separates the Oriental and Australasian realms. This study is intended to be a first step towards a comprehensive revision of the group on both genus and species levels. Additionally, critical problems and prospects for rhagophthalmid research are briefly discussed.

Diversity of the Paedomorphic Snail-Eating Click-Beetle Genus Malacogaster Bassi, 1834 (Elateridae: Agrypninae: Drilini) in the Mediterranean

The soft-bodied click-beetle genus Malacogaster Bassi, 1834 from the Mediterranean region has never been taxonomically revised to date. Information on its morphology, intra- and interspecific variability, systematics and distribution is fragmented and most species have not been properly studied since their description. Therefore, in this study we summarize all available information on the genus Malacogaster. Altogether, we recognize 10 valid species from the area including the Canary Islands, Iberian Peninsula, Balearic Islands, northern coast of Africa, Sardinia, and Sicily. Malacogaster ruficollis Dodero, 1925, stat. nov., which was originally described as a variety of M. bassii Lucas, 1870 and later synonymized with it, is considered a separate species. Malacogaster parallelocollis Reitter, 1894, syn. nov. and M. olcesei var. reductus Pic, 1951, syn. nov. are synonymized with M. maculiventris Reitter, 1894. Malacogaster notativentris Pic, 1951, syn. nov. and M. olcesei Pic, 1951, syn. nov. are synonymized with M. passerinii Bassi, 1834. Lectotypes are designated for M. maculiventris Reitter, 1894, M. nigripes heydeni Reitter, 1894, M. parallelocollis Reitter, 1894, M. thoracica Redtenbacher, 1858, M. olcesei Pic, 1951, and M. rubripes Peyerimhoff, 1949 to fix their identity.

Beetle bioluminescence outshines extant aerial predators

We understand very little about the timing and origins of bioluminescence, particularly as a predator avoidance strategy. Understanding the timing of its origins, however, can help elucidate the evolution of this ecologically important signal. Using fireflies, a prevalent bioluminescent group where bioluminescence primarily functions as aposematic and sexual signals, we explore the origins of this signal in the context of their potential predators. Divergence time estimations were performed using genomic-scale datasets providing a robust estimate for the origin of firefly bioluminescence as both a terrestrial and as an aerial signal. Our results recover the origin of terrestrial beetle bioluminescence at 141.17 (122.63-161.17) Ma and firefly aerial bioluminescence at 133.18 (117.86-152.47) Ma using a large dataset focused on Lampyridae; and terrestrial bioluminescence at 148.03 (130.12-166.80) Ma, with the age of aerial bioluminescence at 104.97 (99.00-120.90) Ma using a complementary Elateroidea dataset. These ages pre-date the origins of all known extant aerial predators (i.e. bats and birds) and support much older terrestrial predators (assassin bugs, frogs, ground beetles, lizards, snakes, hunting spiders and harvestmen) as the drivers of terrestrial bioluminescence in beetles. These ages also support the hypothesis that sexual signalling was probably the original function of this signal in aerial fireflies.

The SITE-100 Project: Site-Based Biodiversity Genomics for Species Discovery, Community Ecology, and a Global Tree-of-Life

Most insect communities are composed of evolutionarily diverse lineages, but detailed phylogenetic analyses of whole communities are lacking, in particular in species-rich tropical faunas. Likewise, our knowledge of the Tree-of-Life to document evolutionary diversity of organisms remains highly incomplete and especially requires the inclusion of unstudied lineages from species-rich ecosystems. Here we present the SITE-100 program, which is an attempt at building the Tree-of-Life from whole-community sampling of high-biodiversity sites around the globe. Combining the local site-based sets into a global tree produces an increasingly comprehensive estimate of organismal phylogeny, while also re-tracing evolutionary history of lineages constituting the local community. Local sets are collected in bulk in standardized passive traps and imaged with large-scale high-resolution cameras, which is followed by a parataxonomy step for the preliminary separation of morphospecies and selection of specimens for phylogenetic analysis. Selected specimens are used for individual DNA extraction and sequencing, usually to sequence mitochondrial genomes. All remaining specimens are bulk extracted and subjected to metabarcoding. Phylogenetic analysis on the mitogenomes produces a reference tree to which short barcode sequences are added in a secondary analysis using phylogenetic placement methods or backbone constrained tree searches. However, the approach may be hampered because (1) mitogenomes are limited in phylogenetic informativeness, and (2) site-based sampling may produce poor taxon coverage which causes challenges for phylogenetic inference. To mitigate these problems, we first assemble nuclear shotgun data from taxonomically chosen lineages to resolve the base of the tree, and add site-based mitogenome and DNA barcode data in three hierarchical steps. We posit that site-based sampling, though not meeting the criterion of “taxon-completeness,” has great merits given preliminary studies showing representativeness and evenness of taxa sampled. We therefore argue in favor of site-based sampling as an unorthodox but logistically efficient way to construct large phylogenetic trees.

Dominican amber net-winged beetles suggest stable paleoenvironment as a driver for conserved morphology in a paedomorphic lineage

Paedomorphosis is a heterochronic syndrome in which adult individuals display features of their immature forms. In beetles, this phenomenon occurs widely in the superfamily Elateroidea, including the net-winged beetles (Lycidae), and, due to the usual flightlessness of paedomorphic females, it is hypothesized to cause speciation rates higher than in non-paedomorphic lineages. However, some fossils of paedomorphic lycids do not support this with palaeobiological data. Discovery of new Lycidae fossils attributed to the West Indian extant paedomorphic genus Cessator Kazantsev in the Dominican amber also suggests morphological stasis within this genus in the Greater Antilles. We describe Cessator anachronicus Ferreira and Ivie, sp. nov. based on adult males, as well as the first ever recorded fossil net-winged beetle larva of the same genus. We propose that the relatively young age of the studied fossils combined with the stable conditions in the forest floor of the Greater Antilles through the last tens of million years could explain the exceptionally conserved morphology in the net-winged beetles affected by the paedomorphic syndrome.

A new species of Petalacmis firefly from Bolivia, with a key to species (Coleoptera, Lampyridae)

Petalacmis Olivier, 1908 is a poorly known genus of firefly endemic to South America and is currently the only member of the subfamily Lampyrinae, tribe Lampyrini known to occur on the continent. Here, we describe a new species, Petalacmistriplehorni sp. nov. from Bolivia and compare it to the two other described species in the genus. A key to Petalacmis species based on male traits, as well as illustrations of morphological features, are given in detail for the first time. We present unique, previously neglected traits of Petalacmis species and compare them to other Lampyrinae.

Phylogenomic and mitogenomic data can accelerate inventorying of tropical beetles during the current biodiversity crisis

Conservation efforts must be evidence-based, so rapid and economically feasible methods should be used to quantify diversity and distribution patterns. We have attempted to overcome current impediments to the gathering of biodiversity data by using integrative phylogenomic and three mtDNA fragment analyses. As a model, we sequenced the Metriorrhynchini beetle fauna, sampled from ~700 localities in three continents. The species-rich dataset included ~6,500 terminals, ~1,850 putative species delimited at 5% uncorrected pairwise threshold, possibly ~1,000 of them unknown to science. Neither type of data could alone answer our questions on biodiversity and phylogeny. The phylogenomic backbone enabled the integrative delimitation of robustly defined natural genus-group units that will inform future research. Using constrained mtDNA analysis, we identified the spatial structure of species diversity, very high species-level endemism, and a biodiversity hotspot in New Guinea. We suggest that focused field research and subsequent laboratory and bioinformatic workflow steps would substantially accelerate the inventorying of any hyperdiverse tropical group with several thousand species. The outcome would be a scaffold for the incorporation of further data from environmental sequencing and ecological studies. The database of sequences could set a benchmark for the spatiotemporal evaluation of biodiversity, would support evidence-based conservation planning, and would provide a robust framework for systematic, biogeographic, and evolutionary studies.

An unusual elateroid lineage from mid-Cretaceous Burmese amber (Coleoptera: Elateroidea)

We here report a new elateroid, Anoeuma lawrencei Li, Kundrata and Cai gen. et sp. nov., from mid-Cretaceous Burmese amber. Though superficially similar to some soft-bodied archostematans, Anoeuma could be firmly placed in the polyphagan superfamily Elateroidea based on the hind wing venation. Detailed morphological comparisons between extant elateroids and the Cretaceous fossils suggest that the unique character combination does not fit with confidence into any existing soft-bodied elateroid group, although some characters indicate possible relationships between Anoeuma and Omalisinae. Our discovery of this new lineage further demonstrates the past diversity and morphological disparity of soft-bodied elateroids.

Hide-and-Seek with Tiny Neotenic Beetles in One of the Hottest Biodiversity Hotspots: Towards an Understanding of the Real Diversity of Jurasaidae (Coleoptera: Elateroidea) in the Brazilian Atlantic Forest

Jurasaidae are a family of neotenic elateroid beetles which was described recently from the Brazilian Atlantic Forest biodiversity hotspot based on three species in two genera. All life stages live in the soil, including the larviform females, and only adult males are able to fly. Here, we report the discovery of two new species, Jurasai miraculum sp. nov. and J. vanini sp. nov., and a new, morphologically remarkable population of J. digitusdei Rosa et al., 2020. Our discovery sheds further light on the diversity and biogeography of the group. Most species of Jurasaidae are known from the rainforest remnants of the Atlantic Forest, but here for the first time we report a jurasaid species from the relatively drier Atlantic Forest/Caatinga transitional zone. Considering our recent findings, minute body size and cryptic lifestyle of all jurasaids, together with potentially high numbers of yet undescribed species of this family from the Atlantic Forest and possibly also other surrounding ecoregions, we call for both field research in potentially suitable localities as well as for a detailed investigation of a massive amount of already collected but still unprocessed materials deposited in a number of Brazilian institutes, laboratories and collections.

The Fossil Record of Elateridae (Coleoptera: Elateroidea): Described Species, Current Problems and Future Prospects

The Elateridae (click-beetles) are the largest family in Elateroidea; however, their relationships, systematics and classification remain unclear. Our understanding of the origin, evolution, palaeodiversity and palaeobiogeography of Elateridae, as well as reconstruction of a reliable time-calibrated phylogeny for the group, are hampered by the lack of detailed knowledge of their fossil record. In this study, we summarize the current knowledge on all described fossil species in Elateridae, including their type material, geographic origin, age, bibliography and remarks on their systematic placement. Altogether, 261 fossil species classified in 99 genera and nine subfamilies are currently listed in this family. The Mesozoic click-beetle diversity includes 143 species, with most of them described from the Jurassic Karatau, and 118 described species are known from the Cenozoic deposits, mainly from the Eocene North American Florissant Formation and European Baltic amber. Available data on the described past diversity of Elateridae suggest that almost all fossil lineages in this group are in urgent need of revision and numerous Mesozoic species might belong to different families. Our study is intended to serve as a comprehensive basis for all subsequent research focused on the click-beetle fossil record.

Conspicuousness, phylogenetic structure, and origins of Müllerian mimicry in 4000 lycid beetles from all zoogeographic regions

Biologists have reported on the chemical defences and the phenetic similarity of net-winged beetles (Coleoptera: Lycidae) and their co-mimics. Nevertheless, our knowledge has remained fragmental, and the evolution of mimetic patterns has not been studied in the phylogenetic context. We illustrate the general appearance of ~ 600 lycid species and ~ 200 co-mimics and their distribution. Further, we assemble the phylogeny using the transcriptomic backbone and ~ 570 species. Using phylogenetic information, we closely scrutinise the relationships among aposematically coloured species, the worldwide diversity, and the distribution of aposematic patterns. The emitted visual signals differ in conspicuousness. The uniform coloured dorsum is ancestral and was followed by the evolution of bicoloured forms. The mottled patterns, i.e. fasciate, striate, punctate, and reticulate, originated later in the course of evolution. The highest number of sympatrically occurring patterns was recovered in New Guinea and the Andean mountain ecosystems (the areas of the highest abundance), and in continental South East Asia (an area of moderate abundance but high in phylogenetic diversity). Consequently, a large number of co-existing aposematic patterns in a single region and/or locality is the rule, in contrast with the theoretical prediction, and predators do not face a simple model-like choice but cope with complex mimetic communities. Lycids display an ancestral aposematic signal even though they sympatrically occur with differently coloured unprofitable relatives. We show that the highly conspicuous patterns evolve within communities predominantly formed by less conspicuous Müllerian mimics and, and often only a single species displays a novel pattern. Our work is a forerunner to the detailed research into the aposematic signalling of net-winged beetles.

Cretophengodidae, a new Cretaceous beetle family, sheds light on the evolution of bioluminescence

Bioluminescent beetles of the superfamily Elateroidea (fireflies, fire beetles, glow-worms) are the most speciose group of terrestrial light-producing animals. The evolution of bioluminescence in elateroids is associated with unusual morphological modifications, such as soft-bodiedness and neoteny, but the fragmentary nature of the fossil record discloses little about the origin of these adaptations. We report the discovery of a new bioluminescent elateroid beetle family from the mid-Cretaceous of northern Myanmar (ca 99 Ma), Cretophengodidae fam. nov. Cretophengodes azari gen. et sp. nov. belongs to the bioluminescent lampyroid clade, and would appear to represent a transitional fossil linking the soft-bodied Phengodidae + Rhagophthalmidae clade and hard-bodied elateroids. The fossil male possesses a light organ on the abdomen which presumably served a defensive function, documenting a Cretaceous radiation of bioluminescent beetles coinciding with the diversification of major insectivore groups such as frogs and stem-group birds. The discovery adds a key branch to the elateroid tree of life and sheds light on the evolution of soft-bodiedness and the historical biogeography of elateroid beetles.

Sexually dimorphic characters and shared aposematic patterns mislead the morphology-based classification of the Lycini (Coleoptera: Lycidae)

The Lycini (Elateroidea: Lycidae) contains > 400 species placed in four typologically based genera and numerous subgenera. We assembled a mito-ribosomal dataset representing ~100 species from the whole range and recovered a phylogeny rejecting Lycus and Lycostomus as polyphyletic assemblages. The male-specific wide elytra and elytral thorns are identified in unrelated Neolycus and Lycus. The morphological similarity based on sexual dimorphism and aposematic patterns defined terminal clades and misled the genus-rank classification. We delimit Neolycus, Rhyncheros reinst. name (= Thoracocalon syn. nov. = Lyconotus syn. nov.), LipernesLycostomus, Haplolycus and Lycus. Demosis and six subgenera of Lycus are synonymized with Lycus. Celiasis Laporte, 1840 is kept in the classification as a nomen dubium until any specimen is available. The deep lineages are known from the Americas and Asia. Africa was colonized by Lycus and Haplolycus. Each specific aposematic pattern occurs in a limited range, and the similar body shape and coloration evolved in unrelated sympatrically occurring lineages. High intraspecific polymorphism is putatively a result of the adaptation of various populations to local mimetic assemblages. Therefore, the delimitation of many phenotypically diverse species should be investigated.

Interactions in multi-pattern Müllerian communities support origins of new patterns, false structures, imperfect resemblance and mimetic sexual dimorphism

Mimicry is a hot spot of evolutionary research, but de novo origins of aposematic patterns, the persistence of multiple patterns in Müllerian communities, and the persistence of imperfect mimics still need to be investigated. Local mimetic assemblages can contain up to a hundred of species, their structure can be a result of multiple dispersal events, and the gradual build-up of the communities. Here, we investigate the structure of lowland and mountain mimetic communities of net-winged beetles by sampling the Crocker Range in north-eastern Borneo and neighbouring regions. The local endemics evolved from the Bornean lowland fauna which is highly endemic at the species level. We inferred that metriorrhynchine net-winged beetles evolved in high elevations yellow/black and reticulate aposematic high-contrast signals from a widespread low-contrast brown/black pattern. As the mountain range is ~ 6 million years old, and these patterns do not occur elsewhere, we assume their in situ origins. We demonstrate that a signal with increased internal contrast can evolve de novo in a mimetic community and can persist despite its low frequency. Additionally, a similar aposematic signal evolves from different structures and its similarity is imperfect. The community with multiple patterns sets conditions for the evolution of aposematic sexual dimorphism as demonstrated by the yellow/black male and reticulate female pattern of Micronychus pardus. These insights elucidate the complex character of the evolution of mimetic signalling in the dynamically diversifying biota of high tropical mountains.

Hidden diversity in the Brazilian Atlantic rainforest: the discovery of Jurasaidae, a new beetle family (Coleoptera, Elateroidea) with neotenic females

Beetles are the most species-rich animal radiation and are among the historically most intensively studied insect groups. Consequently, the vast majority of their higher-level taxa had already been described about a century ago. In the 21st century, thus far, only three beetle families have been described de novo based on newly collected material. Here, we report the discovery of a completely new lineage of soft-bodied neotenic beetles from the Brazilian Atlantic rainforest, which is one of the most diverse and also most endangered biomes on the planet. We identified three species in two genera, which differ in morphology of all life stages and exhibit different degrees of neoteny in females. We provide a formal description of this lineage for which we propose the new family Jurasaidae. Molecular phylogeny recovered Jurasaidae within the basal grade in Elateroidea, sister to the well-sclerotized rare click beetles, Cerophytidae. This placement is supported by several larval characters including the modified mouthparts. The discovery of a new beetle family, which is due to the limited dispersal capability and cryptic lifestyle of its wingless females bound to long-term stable habitats, highlights the importance of the Brazilian Atlantic rainforest as a top priority area for nature conservation.

Multiple paedomorphic lineages of soft-substrate burrowing invertebrates: parallels in the origin of Xenocratena and Xenoturbella

Paedomorphosis is an important evolutionary force. It has previously been suggested that a soft-substrate sediment-dwelling (infaunal) environment facilitates paedomorphic evolution in marine invertebrates. However, until recently this proposal was never rigorously tested with robust phylogeny and broad taxon selection. Here, for the first time, we present a molecular phylogeny for a majority of the 21 families of one of the largest nudibranch subgroups (Aeolidacea) and show that the externally highly simplified vermiform nudibranch family, Pseudovermidae, with clearly defined paedomorphic traits and inhabiting a soft-substrata environment, is a sister group to the complex nudibranch family, Cumanotidae. We also report the rediscovery of one of the most enigmatic nudibranchs-Xenocratena suecica-on the Swedish and Norwegian coasts 70 years after it was first found. Xenocratena was described from the same location and environment in the Swedish Gullmar fjord as one of the most enigmatic vermiform organisms, Xenoturbella bocki, which represents either an original simple bilaterian body plan or secondary simplification of a more complex organisation. Our results show that Xenocratena suecica reveals an onset of parallel paedomorphic evolution so we have proposed the new family, Xenocratenidae fam. n., to accommodate the molecular and morphological disparities we discovered. The paedomorphic origin of another aeolidacean family, Embletoniidae, is also demonstrated for the first time. Thus, by presenting three independent lineages from non-closely related aeolidacean families, Xenocratenidae fam. n., Cumanotidae and Embletoniidae, we confirm with phylogenetic data that a soft-substrata burrowing-related environment strongly favours paedomorphic evolution. We suggest criteria to distinguish ancestral and derived characters in the context of modifications of ontogenetic cycles. Applying an evolutionary model of the soft substrate-driven multiple paedomorphic origin of several families of nudibranch molluscs we propose that it is plausible to extend this model to other marine invertebrates and suggest that the ancestral organisation of the enigmatic metazoan, Xenoturbella, might correspond to the larval part of a complex ancestral bilaterian ontogenetic cycle with sedentary/semi-sedentary adult stages and planula-like larval stages.

One less mystery in Coleoptera systematics: the position of Cydistinae (Elateriformia incertae sedis) resolved by multigene phylogenetic analysis

Cydistinae are a rare monogeneric beetle lineage from Asia with a convoluted history of classification, historically placed in various groups within the series Elateriformia. However, their position has never been rigorously tested. To resolve this long-standing puzzle, we are the first to present sequences of two nuclear and two mitochondrial markers for four species of Cydistinae to determine their phylogenetic position. We included these sequences in two rounds of analyses: one including a broad Elateriformia dataset to test placement at the superfamily/family level, and a second, including a richer, targeted sampling of presumed close relatives. Our results strongly support Cydistinae as sister to Phengodidae in a clade with Rhagophthalmidae. Based on our molecular phylogenetic results and examination of morphological characters, we hereby transfer the formerly unplaced Cydistinae into Phengodidae and provide diagnoses for the newly circumscribed Phengodidae, Cydistinae and Cydistus. Since both Phengodidae and Rhagophthalmidae have bioluminescent larvae and strongly neotenic females, similar features can be hypothesized for Cydistinae. Additionally, Cydistus minor is transferred to the new genus Microcydistus.

Molecular phylogeny reveals the gradual evolutionary transition to soft-bodiedness in click-beetles and identifies sub-Saharan Africa as a cradle of diversity for Drilini (Coleoptera: Elateridae)

Drilini are soft-bodied predatory click-beetles (Elateridae: Agrypninae) with incompletely metamorphosed females. Due to divergent morphology, their classification has been contentious. We present the first densely sampled molecular phylogeny of Drilini based on nuclear and mitochondrial markers. Altogether, 44 species, representing all genera, were analysed using maximum likelihood and the Bayesian approach. Molecular analyses recovered five major clades that were also well supported by morphology. Afrotropical lineages mark deep splits. Most Palearctic species belong to a terminal clade. A few species of the predominantly Afrotropical Selasia are distributed from Arabia up to the Himalayas and Thailand. The origin of Drilini is dated to the Late Eocene (~35.5 Mya) and rapid radiation is identified from the Eocene/Oligocene to the Middle Miocene. We describe the gradual transformation of male morphological traits, e.g. the level of sclerotization, structure of mouthparts, loss of the thoracic interlocking mechanism, shortened elytra and expanded larviform abdomen. Five new genera, Austroselasia, Habeshaselasia, Illubaboria, Malacodrilus and Mashaselasia are proposed. Latoselasia, previously a subgenus of Wittmerselasia, is elevated to the genus rank. Five new species, Habeshaselasia nekemtensis, H. illubaborensis, Illubaboria bicolor, Malacodrilus hajeki and Mashaselasia aethiopica are described.

Multilevel fine-scale diversity challenges the 'cryptic species' concept

‘Cryptic’ species are an emerging biological problem that is broadly discussed in the present study. Recently, a cryptic species definition was suggested for those species which manifest low morphological, but considerable genetic, disparity. As a case study we present unique material from a charismatic group of nudibranch molluscs of the genus Trinchesia from European waters to reveal three new species and demonstrate that they show a dual nature: on one hand, they can be considered a ‘cryptic’ species complex due to their overall similarity, but on the other hand, stable morphological differences as well as molecular differences are demonstrated for every species in that complex. Thus, this species complex can equally be named ‘cryptic’, ‘pseudocryptic’ or ‘non-cryptic’. We also present evidence for an extremely rapid speciation rate in this species complex and link the species problem with epigenetics. Available metazoan-wide data, which are broadly discussed in the present study, show the unsuitability of a ‘cryptic’ species concept because the degree of crypticity represents a continuum when a finer multilevel morphological and molecular scale is applied to uncover more narrowly defined species making the ‘cryptic’ addition to ‘species’ redundant. Morphological and molecular methods should be applied in concordance to form a fine-scale multilevel taxonomic framework, and not necessarily implying only an a posteriori transformation of exclusively molecular-based ‘cryptic’ species into morphologically-defined ‘pseudocryptic’ ones. Implications of the present study have importance for many fields, including conservation biology and fine-scale biodiversity assessments.

The Malacca Strait separates distinct faunas of poorly-flying Cautires net-winged beetles

We investigated the spatial and temporal patterns of Cautires diversification on the Malay Peninsula and Sumatra to understand if the narrow and frequently dry Malacca Strait separates different faunas. Moreover, we analyzed the origin of Cautires in Malayan and Sumatran mountains. We sampled 18 localities and present the mtDNA-based phylogeny of 76 species represented by 388 individuals. The phylogenetic tree was dated using mtDNA evolution rates and the ancestral ranges were estimated using the maximum likelihood approach. The phylogeny identified multiple lineages on the Malay Peninsula since the Upper Eocene (35 million years ago, mya) and a delayed evolution of diversity in Sumatra since the Upper Oligocene (26 mya). A limited number of colonization events across the Malacca Strait was identified up to the Pliocene and more intensive faunal exchange since the Pleistocene. The early colonization events were commonly followed by in situ diversification. As a result, the Malacca Strait now separates two faunas with a high species-level turnover. The montane fauna diversified in a limited space and seldom took part in colonization events across the Strait. Besides isolation by open sea or a savannah corridor, mimetic patterns could decrease the colonization capacity of Cautires. The Malay fauna is phylogenetically more diverse and has a higher value if conservation priorities should be defined.

Genome sequences identify three families of Coleoptera as morphologically derived click beetles (Elateridae)

Plastoceridae Crowson, 1972, Drilidae Blanchard, 1845 and Omalisidae Lacordaire, 1857 (Elateroidea) are families of the Coleoptera with obscure phylogenetic relationships and modified morphology showing neotenic traits such as soft bodies, reduced wing cases and larviform females. We shotgun sequenced genomes of Plastocerus, Drilus and Omalisus and incorporated them into data matrices of 66 and 4202 single-copy nuclear genes representing Elateroidea. Phylogenetic analyses indicate their terminal positions within the broadly defined well-sclerotized and fully metamorphosed Elateridae and thus Omalisidae should now be considered as Omalisinae stat. nov. in Elateridae Leach, 1815. The results support multiple independent origins of incomplete metamorphosis in Elateridae and indicate the parallel evolution of morphological and ecological traits. Unlike other neotenic elateroids derived from the supposedly pre-adapted aposematically coloured and unpalatable soft-bodied elateroids, such as fireflies (Lampyridae) and net-winged beetles (Lycidae), omalisids and drilids evolved from well-sclerotized click beetles. These findings suggest sudden morphological shifts through incomplete metamorphosis, with important implications for macroevolution, including reduced speciation rate and high extinction risk in unstable habitats. Precise phylogenetic placement is necessary for studies of the molecular mechanisms of ontogenetic shifts leading to profoundly changed morphology.

Molecular Phylogeny, Diversity and Zoogeography of Net-Winged Beetles (Coleoptera: Lycidae)

We synthesize the evidence from molecular phylogenetics, extant distribution, and plate tectonics to present an insight in ancestral areas, dispersal routes and the effectiveness of geographic barriers for net-winged beetle tribes (Coleoptera: Lycidae). Samples from all zoogeographical realms were assembled and phylogenetic relationships for ~550 species and 25 tribes were inferred using nuclear rRNA and mtDNA markers. The analyses revealed well-supported clades at the rank of tribes as they have been defined using morphology, but a low support for relationships among them. Most tribes started their diversification in Southeast and East Asia or are endemic to this region. Slipinskiini and Dexorini are Afrotropical endemics and Calopterini, Eurrhacini, Thonalmini, and Leptolycini remained isolated in South America and the Caribbean after their separation from northern continents. Lycini, Calochromini, and Erotini support relationships between the Nearctic and eastern Palearctic faunas; Calochromini colonized the Afrotropical realm from East Asia and Metriorrhynchini Afrotropical and Oriental realms from the drifting Indian subcontinent. Most tribes occur in the Oriental and Sino-Japanese realms, the highest alpha-taxonomic diversity was identified in Malesian tropical rainforests. The turn-over at zoogeographical boundaries is discussed when only short distance over-sea colonization events were inferred. The lycid phylogeny shows that poor dispersers can be used for reconstruction of dispersal and vicariance history over a long time-span, but the current data are insufficient for reconstruction of the early phase of their diversification.

Genome sequencing of Rhinorhipus Lawrence exposes an early branch of the Coleoptera

Background

Rhinorhipidae Lawrence, 1988 is an enigmatic beetle family represented by a single species, Rhinorhipus tamborinensis Lawrence, 1988, from Australia, with poorly established affinities near the superfamily Elateroidea (click beetles, soldier beetles and fireflies) or the more inclusive series (infraorder) Elateriformia. Its evolutionary position may inform the basal relationships of the suborder Polyphaga, the largest clade of Coleoptera.

Results

We analyzed four densely sampled DNA datasets of major coleopteran lineages for mitogenomes, rRNA genes and single copy nuclear genes. Additionally, genome sequencing was used for incorporation of R. tamborinensis into a set of 4220 orthologs for 24 terminals representing 12 polyphagan superfamilies. Topologies differed to various degrees, but all consistently refute the proposed placement of Rhinorhipidae in Elateroidea and instead indicate either sister relationships with other Elateriformia, frequently together with Nosodendridae, another divergent small family hitherto placed in Derodontoidea, or in an isolated position among the deepest lineages of Polyphaga. The phylogenomic analyses recovered Rhinorhipus in a sister position to all other Elateriformia composed of five superfamilies. Therefore, we erect the new superfamily Rhinorhipoidea Lawrence, 1988, stat. Nov., with the type-family Rhinorhipidae. The origins of the Rhinorhipidae were dated to the Upper Triassic/Lower Jurassic at the very early phase of polyphagan diversification.

Conclusions

Thus, Rhinorhipidae adds another example to several recently recognized ancient relict lineages which are interspersed within contemporaneous hugely species-rich lineages of Coleoptera.

Electronic supplementary material

The online version of this article (10.1186/s12983-018-0262-0) contains supplementary material, which is available to authorized users.

First true brackish-water nudibranch mollusc provides new insights for phylogeny and biogeography and reveals paedomorphosis-driven evolution

A unique example of brackish water fjord-related diversification of a new nudibranch genus and species Bohuslania matsmichaeli gen. n., sp. n. is presented. There are only few previously known brackish-water opisthobranchs and B. matsmichaeli gen. n., sp. n. is the first ever described brackish-water nudibranch with such an extremely limited known geographical range and apparently strict adherence to salinity levels lower than 20 per mille. Up to date the new taxon has been found only in a very restricted area in the Idefjord, bordering Sweden and Norway, but not in any other apparently suitable localities along the Swedish and Norwegian coasts. We also show in this study for the first time the molecular phylogenetic sister relationship between the newly discovered genus Bohuslania and the genus Cuthona. This supports the validity of the family Cuthonidae, which was re-established recently. Furthermore, it contributes to the understanding of the evolutionary patterns and classification of the whole group Nudibranchia. Molecular and morphological data indicate that brackish water speciation was triggered by paedomorphic evolution among aeolidacean nudibranchs at least two times independently. Thus, the present discovery of this new nudibranch genus contributes to several biological fields, including integration of molecular and morphological data as well as phylogenetic and biogeographical patterns.

Incomplete sclerotization and phylogeny: The phylogenetic classification of Plastocerus (Coleoptera: Elateroidea)

The relationships of the monogeneric family Plastoceridae Crowson, 1972 (Coleoptera: Elateroidea) have remained contentious due to its modified morphology, incorrect information on incomplete metamorphosis of females and the absence of molecular data. We produced the sequences for P. angulosus (Germar, 1844) (the type-species of Plastocerus Schaum, 1852) and performed molecular phylogenetic analyses to estimate its position. The analyses of Elateroidea (186 spp.) and Elateridae (110 spp.) molecular datasets of two mitochondrial and two nuclear gene fragments repeatedly placed Plastocerus Schaum, 1852 in relationships with the elaterid genera Oxynopterus Hope, 1842 and Pectocera Hope, 1842. Alternative topologies were rejected by likelihood tests. Therefore, Plastoceridae Crowson, 1972 are down-ranked to the subfamily Plastocerinae in Elateridae Leach, 1815. We suggest that the morphology-based placement and high rank for some elateroid lineages were inferred from the presence of homoplasies which evolved due to incomplete sclerotization. Distantly related soft-bodied elateroids share freely movable and transverse coxae, a shortened prosternum, and a weakly sclerotized abdomen with free ventrites. Importantly, the apomorphic structures characteristic for their closest relatives, such as the prosternal process, mesoventral cavity, and intercoxal keel in the first abdominal ventrite are regularly absent. Consequently, morphology-based phylogenetic analyses suggest deeply rooted positions for lineages without expressed apomorphic character states. Molecular data represent an independent character system that is not affected by the convergent morphological evolution, and therefore molecular phylogenies can elucidate the relationships of incompletely sclerotized lineages.

Slowly dispersing neotenic beetles can speciate on a penny coin and generate space-limited diversity in the tropical mountains

We demonstrate the controversial origin of a biological species within an area of a few kilometres in the absence of physical barriers. We employed nuclear rRNA/mitochondrial and genome-wide SNP approaches to infer relationships of four species of net-winged beetles characterised by female neoteny. Three species are distributed at low elevations and a single population colonised a 40 km(2) highland plateau and established distinct biological species despite incomplete genetic isolation. The speciation process is extreme in the highly localised spatial scale, due to the low dispersal power of neotenics, and provides clear support for a microallopatric model based on ecological conditions. In contrast with neutral evolution in a homogenous environment, as demonstrated by the genetic divergence and morphological similarity of two widely distributed low-mountain species, the environmental characteristics of the high-mountain plateau led to the origin of a species adapted to the local mimetic pattern and characterised by morphologically distinct genitalia. We conclude that the low dispersal propensity promotes neutral genetic differentiation in the first stage, but environmental characteristics play an important role the final phase of the speciation process. The unexpected speciation at such an extreme geographic scale points to the in situ origin and uniqueness of the mountain fauna.