Phylogenetic Analysis of Hydrophiloidea (Coleoptera: Polyphaga) Based on Molecular Data and Morphological Characters of Adults and Immature Stages

Home , Anacaena, Cercyon ustulatus, Cymbiodyta, Dendrophilus, Dendrophilus punctatus, Georissus

Insect Systematics & Evolution 40 (2009) 3–41 brill.nl/ise

Phylogenetic analysis of Hydrophiloidea (Coleoptera: Polyphaga) based on molecular data and morphological characters of adults and immature stages

Detlef Bernharda, * , Ignacio Riberab , Albrecht Komarekc and Rolf G. Beuteld a Universität Leipzig, Institut für Biologie II, Molekulare Evolution & Systematik der Tiere, Talstrasse 33, 04103 Leipzig, Germany bMuseo Nacional de Ciencias Naturales, Madrid, Spain cNaturhistorisches Museum Wien, Burgring 7, A-1010 Wien, Austria dInstitut für Spezielle Zoologie und Evolutionsbiologie, Friedrich Schiller Universität Jena, Erbertstr. 1, 07743 Jena, Germany * Corresponding author, e-mail: [email protected]

An extensive combined data set comprising 160 morphological characters of adults and immature stages of Hydrophiloidea and sequences of six diff erent genes were analysed using parsimony and a Bayesian approach. Analyses were carried out with equal weight for individual morphological and molecular characters, and alternatively with approximately equivalent weight for the entire partitions, i.e., 147 informative morphological characters × 9.5 ≈ 1383 informative molecular characters. With the former approach some conventional groups such as the histeroid lineage (Histeridae and Sphaeritidae), Helophorinae and Sphaeridiinae were recovered. However, the branching pattern as a whole is strongly in contrast to the results of previous studies. Th e results obtained with the modifi ed weighting scheme (9.5:1) conform more to morphology based analyses. Th e monophyly of Hydrophiloidea, Histeridae + Sphaeritidae, Epimetopinae + Georissinae, Helophorinae, Sphaeridiinae and of the hydrophiline-sphaeridiine lineage is supported in the parsimony analysis. Spercheinae is placed as sister group of all the remaining hydrophiloid groups and a clade is formed by the subfamilies Epimetopinae, Georissinae, Hydrochinae and Helophorinae. In the Bayesian analysis the monophyly of Hydrophilidae is supported. Georissinae form a clade with Hydrochinae, and Epimetopinae are placed as sister group of a clade comprising Spercheinae + the hydrophiline-sphaeridiine lineage. Berosus is placed as the sister group of the remaining groups of Hydrophilinae-Sphaeridiinae in both analyses, and Sphaeridiinae are always nested within a paraphyletic Hydrophilinae. Th e divergent results of the diff erent analyses show that important questions in the phylogeny of Hydrophiloidea such as for instance the placement of Spercheinae are still open.

Keywords Hydrophiloidea, phylogeny, morphological characters, molecular systematics, combined analysis.

Introduction Hydrophiloidea sensu lato (e.g., Lawrence & Newton 1995; Archangelsky et al. 2005 ) is a group with a world wide distribution. It contains about 475 genera and 6600

© Koninklijke Brill NV, Leiden, 2009 DOI 10.1163/187631209X416741 4 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 described species (Archangelsky et al. 2005 ) grouped in the three terrestrial histeroid families (Synteliidae, Sphaeritidae, Histeridae) and the most speciose, primarily aquatic family Hydrophilidae (Archangelsky et al. 2005 ; Lawrence & Newton 1995). Th e lat- ter group was ranked as a superfamily in alternative classifi cations (e.g., Crowson 1981 ; Hansen 1991 , 1997a , 1999b ; see also Lawrence 1991 ) and divided in six families - Helophoridae, Hydrochidae, Epimetopidae, Georissidae, Spercheidae, and Hydrophi- lidae. Th ese were considered as subfamilies in Lawrence & Newton (1995) and in Löbl & Smetana ( 2004 ). Th is concept was followed by Archangelsky et al. ( 2005 ), with Hydrophilidae divided into nine subfamilies, among them the groups considered as families by Hansen ( 1991 ), and also Horelophinae, Horelophopsinae, Hydrophilinae, and Sphaeridiinae. Th e application of this system in the present contribution does not mean that Hansen’s concept (1991, 1997a, 1999b) is less useful or not phylogeneti- cally justifi ed. It is merely a pragmatic decision in favour of the classifi cation presented in Archangelsky et al. (2005 ). Hydrophiloidea are one of the most studied groups of Coleoptera in terms of morphology and taxonomy (e.g., Archangelsky 1997 , 1998 , 2001 , 2002 a,b; Beutel 1994 , 1999; Beutel & Komarek 2004 ; Böving & Henriksen 1938 ; Hansen 1987, 1991 , 1995 , 1997, 1999a ,b; Komarek 2004 , 2006 , 2007 ; Komarek & Beutel 2007 ; Richmond 1920 ). Nevertheless, their phylogeny is still controversial (see e.g., Hansen 1991 , 1997a ; Archangelsky 2004 ; Archangelsky et al. 2005 ; Korte et al. 2004 ; Bernhard et al. 2006). In the last years, an impressive number of studies were dedicated to the morphology, taxonomy and phylogeny of the superfamily. It was treated in detail by Beutel & Leschen (2005) and Archangelsky et al. ( 2005 ). Th e available knowledge on larval morphology (e.g., Archangelsky 1997 , 2001 , 2002a ,b; Archangelsky & Fikácek 2004 ; Beutel 1999) and morphology of adults (Beutel 1994 ; Beutel et al. 2001 ; Anton & Beutel 2004; Beutel & Komarek 2004 ) has distinctly increased. Numerous studies were dedicated to the taxonomy and faunistics (e.g., Komarek 2004 , 2005, 2007 ; Short 2005 ; Short & Perkins 2004 ; Short & Torres 2006 ) and several studies to the phylogeny on lower (e.g., Komarek & Beutel 2007 ; Short & Liebherr 2007 ) and higher levels (Hansen 1991 , 1997a ; Archangelsky 1998 ; Caterino & Vogler 2002 ; Beutel & Komarek 2004 ; Beutel & Leschen 2005 ). Caterino & Vogler ( 2002 ), the fi rst study utilizing combined morphological (larval and adult characters) and molecular data (SSU), was focussed on the phylogeny of the histeroid families. Korte et al. (2004 ) analysed SSU and LSU sequence data aiming at a clarifi cation of staphyliniform interrelationships. A data set comprising six genes (nuclear SSU, LSU and mitochondrial rrnL, rrnS, cox1 and cox2) was analysed by Bernhard et al. ( 2006 ). In the present contribution we have combined this extensive molecular data set with 160 morphological characters of immature stages and adults. Th e focus is on the interrelationships of the major hydrophiloid groups i.e. the families and subfamilies. Th ey are all represented in the data matrices with the exception of the very rare Horelophinae and Horelophopsinae, which are only known as adults and are very rarely collected. Even though what we present here is the largest data set for Hydrophiloidea so far analysed, the taxon sampling within the largest groups, i.e., Histeridae, Sphaeridiinae D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 5 and Hydrophilinae, is limited. However, the data may be used as the basis for future studies with a more extensive taxon sampling and a focus on interrelationships of more subordinate hydrophiloid groups.

Material and methods List of taxa examined We have included representatives of all families of Hydrophiloidea (Archangelsky et al. 2005 ) except for Synteliidae, which were not available for detailed anatomical study and DNA extraction, plus six subfamilies of Hydrophilidae (see below for details of the taxa included: see also Table 1). Trees were rooted with two members of two other families of Staphyliniformia (Leiodidae and Hydraenidae), in which Hydrophiloidea are included (e.g., Beutel & Leschen 2005 ). Hydrophiloidea, Hydrophilidae, Helophorinae: Helophorus aquaticus Linnaeus, 1758, H. arvernicus Mulsant 1846, H. guttulus Motschulsky, 1860, H. nivalis (Giraud, 1851) (4 spp.); larvae: Helophorus sp. Georissinae: Georissus crenulatus (Rossi, 1794); (larva examined at Zoologisk Museum Copenhagen, coll. of Michael Hansen) Hydrochinae: Hydrochus carinatus Germar, 1824, H. ignicollis Motschulsky, 1860) (larvae: H. elongatus [Schaller, 1783]) Spercheinae: Spercheus emarginatus (Schaller, 1783) (larvae and adults, coll. by Ronald Bellstedt) Epimetopinae: Epimetopus sp. (coll. by Andrew Short)

Table 1. Ingroup and outgroup taxa

Ingroup Sphaeritidae (monogeneric) Sphaerites Histerinae Margarinotus , Hololepta * Dendrophilinae Dendrophilus Helophorinae (monogeneric) Helophorus Georissinae (monogeneric) Georissus Epimetopinae Epimetopus Hydrochinae (monogeneric) Hydrochus Spercheinae (monogeneric) Spercheus Hydrophilinae Anacaena , Berosus , Cymbiodyta , Enochrus , Helochares , Hydrobius Sphaeridiinae Cercyon , Coelostoma , Sphaeridium

Outgroup Leiodidae Catops Hydraenidae Ochthebius

*Not in morphological matrix. 6 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

Hydrophilinae: Anacaena globulus (Paykull, 1758), Berosus luridus (Linnaeus, 1761) (larva: Berosus sp.), Cymbiodyta marginella (Fabricius, 1792), Enochrus testaceus (Fabricius 1801), E. quadripunctatus (Herbst, 1792) (2 spp.), Helochares obscurus (O. W. Müller, 1776), Hydrobius fuscipes (Linnaeus, 1758) (larva: Hydrobius sp.), Sphaeridiinae: Cercyon ustulatus (Preysler, 1790), Coelostoma orbiculare (Fabricius, 1775), Sphaeridium bipustulatum (Fabricius, 1781) (larvae and adults), Histeridae: Margarinotus brunneus (Fabricius, 1775), Hololepta plana (Sulzer, 1776) (larvae), Dendrophilus punctatus (Herbst, 1792) (larvae and adults), Sphaeritidae: Sphaerites glabratus (Fabricius, 1792) Staphylinoidea, Leiodidae (outgroup): Catops picipes (larvae and adults) Hydraenidae (outgroup): Ochthebius spp. (larvae and adults)

Morphology Adults of all terminal taxa were examined in detail (except for Hololepta plana ) and larvae of most of the genera included in the analyses. Additional data, especially on morphological features of larvae and adults were extracted from the literature (e.g., Archangelsky 1997 ; Beutel 1999; Costa et al. 1988 ; Hansen 1991 , 1997). We include numerous characters already introduced by other authors, especially Hansen (1991, 1997a ). However, the taxon sampling is diff erent, the coding is modifi ed in many cases, and all defi ned character states are based on original observations (adults).

DNA isolation, PCR ampliﬁ cation and sequencing Frozen specimens of Ochthebius minimus and Catops picipes were pulverized in 1.5 ml microfuge tubes with a pestle followed by a standard DNA extraction using the DTAB- protocol (Gustinich et al. 1991 ). For both species we used the same PCR primers and PCR conditions as described in Bernhard et al. ( 2006 ) to amplify complete nuclear SSU, a 0.7 kb fragment of the nuclear LSU and four regions of the mitochondrial genome: 350 bp of the rrnS, 500 bp of the rrnL, 1200 bp of the cox1 gene, and 700 bp including the complete cox2 gene. Sequencing reactions were performed for both DNA strands using the PCR primers and additional internal sequencing primers for SSU and cox1 on an ABI PRISM 3100 Genetic Analyser. All methods are described in more detail in Bernhard et al. (2006 ). Sequences for the ingroup taxa (Hydrophiloidea and Histeroidea) were from Bernhard et al. ( 2006 ) and Korte et al. ( 2004 ). Th e GenBank accession numbers for the new sequences are FM209286-209293.

Phylogenetic analyses Th e parsimony analyses of the morphological data were carried out with NONA (Goloboff 1995 ) (ratchet, 500). We also used Bayesian methods as implemented in MrBayes 3.1.2 (Huelsenbeck & Ronquist 2001 ), using the evolutionary model for morphological data described in Lewis (2001 ). MrBayes ran for 106 generations using default values, saving trees each 100. “Burn-in” values were established after visual D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 7 examination of a plot of the standard deviation of the split frequencies between two simultaneous runs. Protein coding genes were not length variable, and their alignment was trivial. Ribosomal genes were aligned with multiple progressive pairwise alignment with sec- ondary refi nement using the software MAFFT online v. 6 and the Q-INS-i algorithm (Katoh et al., 2002 ). Th e fi nal alignend matrix had 5032 characters, of which 1383 were informative. Phylogenetic analyses were run in MrBayes 3.1.2, with six partitions (corresponding to the six genes) and a general time reversible (GTR, Rodríguez et al. 1990) evolutionary model, with a proportion of invariable sites (I) and unequal rates (G), with parameters independently estimated for each of the partitions. MrBayes was run for 4×106 generations. Combined data were analysed both with Bayesian probabilities and parsimony. For parsimony we used a TBR heuristic search of 1×104 replicates and the option ‘save multiple trees’ activated, with equally weighted characters. Considering the diff erence in the number of informative characters in the molecular and morphological datasets (1383 and 147, respectively), we explored the results of a scheme in which both partitions have an aproximately equivalent weight (i.e., 147 informative morphological characters × 9.5 ≈ 1383 informative molecular characters). Support was measured with 1000 bootstrap pesudoreplicates (Felsenstein, 1985) of 30 random replicas each, not saving multiple trees. For the Bayesian analyses of the combined data we used the same evolutionary models used in the separate analyses (with parameters newly estimated), run for 2×10 6 generations.

Results Th e parsimony analysis of the morphological data set comprising 134 characters of adult and 26 characters of immature stages (see Appendix A and B) resulted in two minimal length trees with 478 steps (CI: 0.51, RI: 0.67) (Fig. 1). Based on the morphological data alone Spercheinae branch oﬀ ﬁ rst from all remaining hydrophiloid taxa, followed by a group consisting of Georissinae, Epimetopinae, Hydrochinae, and Helophorinae. Th e histeroids (Histeridae and Sphaeritidae) were found as sister group of the hydrophiline-sphaeridiine lineage. Th e standard deviation of the split frequencies between the two simultaneous runs in the Bayesian analyses of the morphological data reached values lower than 0.008 in 7.5×105 generations, and this was taken as the burn-in. Th e majority rule consensus of the remaining trees in the two independent runs had few well supported nodes (tree not shown): the monophyly of Hydrophiloidea (pp 0.99), the monophly of Helophori- nae (pp 0.96), Histeridae + Sphaeritidae (pp 0.99), Hydrophilinae and Sphaeridiinae (hydrophiline-sphaeridiinae lineage) with the exclusion of Berosus (pp 0.97), and some internal nodes within supporting the hydrophiline paraphyly with respect to Sphaeridiinae. Th e monophyly of Sphaeridiinae is highly supported (pp 0.99). Th e parsimony analyses of the equally weighted combined data resulted in three shortest trees of 8092 steps and a CI = 0.4 ( Fig. 2 ). In the strict consensus tree 8 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 Cercyon ustulatus 105 98 83 86 82 78 71 77 67 Dendrophilus punctatus Sphaeridium bibustulatum 54 60 107 74 3303248 15 Margarinotus brunneus 32 145 48 62 121126 34 9 12 20 30 54 114 121122 129 27 120 108 59 49 27 Coelostoma orbiculare 24 Anacaena globulus 11 125 127 128134 135 100 124 133 103 35 16 Georissus 14 10 15 32 49 82 89 95 117 120 Enochrus quadripunctatus Enochrus testaceus Hydrochus carinatus 113116 127 106 159 72 93 128 93 Cymbiodyta marginella 43 90 155 158 Sphaerites glabratus 88 145 31 84 30 31 133 132 Helochares obscurus Epimetopus 109 95 69 66 73 79 34 59 31 Hydrobius fuscipes Helophorus nivalis Helophorus guttulus Helophorus arvernicus Helophorus aquaticus 1 50 53 55 57 64 65 66 68 79 87 90 91 99 101102113116117118 139140 143 147153 154 57 61 32

Berosus luridus 55 114124 128 54 71 94 114 117122 97 105 26 46 34 40 48 80 99 33 158 30 32 135 39 51 59 82 83 95 98 100 51 56 59 73 125 11 12 16 124 9 40 49 13 77 8 7 60 32 33 36 48 66 67 82 84 97 130 54 8 11 12 34 29 1 11 12 27 71 92 93 99 109113121134 145 13 159 156 114 111 110 72 38 1 24 36 63 91 96 105119138 156 43 37 54 81 102109110134 8 16 18 21 24 25 39 49 51 52 58 61 63 70 74 81 86 133 146147148154 157 160 Spercheus emarginatus 5929 48 129 130 2 7 Ochthebius 67 68 137 139140145147148 149150151152 154155 91 95 95 104 105 109114116121 34 2 4 8 13 16 23 26 28 29 41 82 97 100 105 114128132134158159 33 37 38 44 74 98 99 122135136141143 153 5 8 16 25 26 33 34 49 52 53 54 58 64 78 80 86 20 Catops

Fig. 1. Morphological characters, parsimony analysis, strict consensus of two trees (ratchet, 500 replicates), equal weights; characters (see Appendix A) mapped on tree, full quadrangles non-homoplasious characters. D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 9 Hydrochus carinatus Catops picipes Cercyon ustulatus Sphaeridium bipustulatum Coelostoma orbiculare Enochrus quadripunctatus Enochrus testaceus Anacaena globulus Cymbiodyta marginella Helochares obscurus Hydrobius fuscipes Margarinotus brunneus Hololepta plana Dendrophilus punctatus Sphaerites glabratus Spercheus emarginatus Berosus luridus Helophorus arvernicus Helophorus nivalis Helophorus guttulus Helophorus aquaticus Ochthebius Georissus Epimetopus

100

100 100

Fig. 2. Combined data, parsimony analysis, strict consensus of three trees (1×104 random replicas, save multiple trees), equal weights; bootstrap values of selected clades left of branches.

Hydrochinae form the sister group of a clade comprising all other hydrophiloid groups, although with low support (bootstrap value below 50). Helophorinae are monophyletic (bootstrap value 100) and form a polytomy with Georissinae, Epimetopinae and a lineage comprising Sphaeritidae, Histeridae, Spercheinae, Hydrophilinae (paraphyletic) and Sphaeridiinae (bootstrap value 100). Th e histeroid groups and Histeridae (Hololepta , Margarinotus , Dendrophilus ) are monophyletic (bootstrap values 100) and placed as sister group of Spercheinae, but with very low support (boostrap below 50%). With a weigthing scheme molecular = 9.5 × morphology (see Material and methods) a single shortest tree was found ( Fig. 3 ), in which Spercheinae were placed as sister group of the remaining Hydrophiloidea (bootstrap value 52). A clade comprising Epimetopinae + Georissinae (bootstrap value 67) is part of a lineage also comprising Hydrochinae and Helophorinae. Th e histeroid groups and Histeridae are monophyletic (bootstrap values 100) and also the hydrophiline-sphaeridiine lineage. Hydrophilinae is paraphyletic, with Berosus as sister group of the entire remaining hydrophiline- sphaeridiine lineage. Sphaeridiinae is monophyletic (bootstrap value 100), with Anacaena as its sister group. Th e standard deviation of the split frequencies between the two simultaneous runs in the Bayesian analyses of the molecular data stabilised with values lower than 0.005 in 3.5×106 generations, and this was taken as the burn-in. In the majority rule consensus tree (not shown) of the combined runs, Hydrophilidae was monophyletic (pp = 1.0) and sister to a histeroid plus Leiodidae clade, although the later with low 10 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 Cercyon ustulatus Sphaeridium bipustulatum Coelostoma orbiculare Anacaena globulus Enochrus quadripunctatus Enochrus testaceus Cymbiodyta marginella Helochares obscurus Hydrobius fuscipes Berosus luridus Helophorus arvernicus Helophorus nivalis Helophorus guttulus Helophorus aquaticus Epimetopus Georissus Hydrochus carinatus Margarinotus brunneus Hololepta plana Dendrophilus punctatus Sphaerites glabratus Spercheus emarginatus Ochthebius Catops picipes 100 100 100 67 100 100 100 100 90 100 79 100 91 53 86 52 98

Fig. 3. Combined data, bootstrap consensus (1000 pseudoreplicas × 30 random replicas, not save multiple trees), weight molecular = 9.5 × morphology (molecular 5032 total characters/1383 informative, morfo 160 total characters/147 informative, 1383/147 = 9.4).

support (pp = 0.87). Th e monophyly of Sphaeritidae + Histeridae, a clade comprising Hydrophilinae and Sphaeridiinae, and a clade formed by Georissinae, Hydrochinae and Helophorinae was highly supported (pp ≥ 0.99), but the position of Spercheinae and Epimetopinae is unresolved within Hydrophilinae. In agreement with the morphological data, Berosus is placed as sister to the remaining hydrophiline-sphaeridiinae lineage (with equally low support), and Sphaeridiinae are monophyletic but nested within Hydrophilinae, with high support. Th e standard deviation of the split frequencies between the two runs of the Bayesian analyses of the combined data ( Fig. 4 ) stabilised at values below 0.002 at 1.6×10 6 generations, and this was taken as the burn-in value. Th e monophyly of Hydrophiloidea is not conﬁ rmed, as Catops is placed as sister group to the histeroid groups with a posterior probability of 0.99, but the monophyly of hydrophilid subfamilies and the histeroid groups is strongly supported (pp 1.0 in both cases). Within Hydrophilidae, Georissinae, Hydrochinae and Helophorinae form a strongly supported clade, with the former two as the sister group of Helophorinae. Epimetopinae is placed as the sister group of a clade comprising Spercheinae and the hydrophiline-sphaeridiine lineage (with low support), and Spercheinae as the sister group of the hydrophiline- sphaeridiine clade with strong support. Sphaeridiinae are placed as a subordinate clade within the paraphyletic Hydrophilinae, also with strong support. D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 11 Sphaeridiinae “Hydrophilinae” Helophorinae Georissinae Histeridae Leiodidae Hydraenidae Spercheinae Epimetopinae Hydrochinae Sphaeritidae Cercyon ustulatus Sphaeridium bipustulatum Coelostoma orbiculare Enochrus quadripunctatus Enochrus testaceus Cymbiodyta marginella Helochares obscurus Anacaena globulus Hydrobius fuscipes Berosus luridus Spercheus emarginatus Epimetopus Helophorus arvernicus Helophorus nivalis Helophorus guttulus Helophorus aquaticus Georissus Hydrochus carinatus Margarinotus brunneus Hololepta plana Dendrophilus punctatus Sphaerites glabratus Catops picipes Ochthebius 100 100 100 100 99 72 100 100 100 98 100 100 100 96 96 100 99 100 98 74 100

Fig. 4. Combined data, Bayesian analysis.

Discussion Th e selection of the ingroup taxa included in the analyses, i.e., members of both traditional superfamilies Histeroidea and Hydrophiloidea s.str. (e.g., Crowson 1981 ; Hansen 1991 ), was based on the assumption that they together form a monophyletic lineage within Staphyliniformia (e.g., Hansen 1997a ; Beutel & Leschen 2005 ). Th e diff erent analyses we carried out resulted in distinctly diff erent branching patterns. Some of the conventional groups such as the histeroid lineage, Helophorinae, and Sphaeridiinae are supported by the results of the parsimony analysis with equally weighted individual morphological and molecular data like in all other analyses. However, as a whole, the branching pattern obtained ( Fig. 2 : strict consensus tree) is clearly in confl ict with recent studies dealing with the interrelationships of hydrophiloid subgroups (see, e.g., Archangelsky 2004 ) and with the results of the parsimony analyses of the morphological data presented here (Fig. 1). In contrast to all previous studies (e.g., Hansen 1991 ; Archangelsky 1998 ; Beutel 1999; Beutel & Komarek 2004 ; Bernhard et al. 2006 ) Hydrochinae is placed as sister group of all other hydrophiloid subgroups, and Spercheinae as sister group of the histeroid families in the strict consensus tree ( Fig. 2 ). Th ese branches are poorly supported and appear unlikely. Hydrochinae was placed as sister-group of Georissinae within a lineage also comprising Epimetopinae and Helophorinae (=helophorid lineage) by Hansen ( 1991 : preferred 12 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 cladogram, fi g. 5) (176 morphological characters of adults and immature stages) and as sister group of Spercheinae + the hydrophiline-sphaeridiine lineage by Archangelsky (1998 ) (148 morphological characters of adults and immature stages, 90 characters of adults from Hansen 1991 ) and Beutel & Leschen ( 2005 ) (137 morphological characters of adults and immature stages [binary coding] + nine life history characters). A sister group relationship between Hydrochinae and a lineage comprising Epime- topinae + Georissinae was suggested by Korte et al. (2002) (18S and 28S rDNA), and a sister group relationship between Hydrochinae and Spercheinae + the hydrophiline- sphaeridiine lineage in Beutel & Komarek (2004 ) (153 morphological characters of adults and immature stages + four life history characters). Based on the molecular data set also analysed here, a position of Hydrochinae as sister group of Georissinae (parsimony) or of Georissinae + Helophorinae (Bayesian analysis) was obtained by Bernhard et al. (2006). Even though the placement of Hydrochinae is apparently problematic, a basal position appears very unlikely considering the presently available information and morphological data ( Fig. 1 ). Spercheinae were either placed as sister group of the remaining Hydrophilidae (Beutel 1994 ), as sister group of the remaining Hydrophiloidea (Beutel 1999), or as sister group of Hydrophilidae as defi ned by Hansen (1999: Horelophinae, Horelophopsinae, Hydrophilinae, Sphaeridiinae) (Archangelsky 1998 ; Beutel & Komarek 2004 ). Especially larval characters (e.g., deep maxillary grooves, well developed lacinia, stigmatic atrium; Archangelsky 1998 ; Beutel 1999) and specialised aquatic habits of larvae and adults of Spercheinae (e.g., Hansen 1997b ; Archangelsky et al. 2005 ) are in strong confl ict with a hypothesis of close affi nities between Spercheinae and the histeroid families. Th e results obtained with a modifi ed weighting scheme (molecular = 9.5× morphology, see above; Fig. 3) come much closer to results suggested in earlier studies. Like in the fi rst analysis Hydrophiloidea s.l., Histeroidea, Helophorinae and Sphaeridiinae are supported as clades. Another clade, the helophorid lineage as suggested by Hansen ( 1991 ), is supported with a very low bootstrap value. It comprises Epimetopinae + Georissinae (see also Fig. 1 [morphological data] and Beutel 1994 ; Archangelsky 1998 ; Beutel & Komarek 2004 ; Beutel & Leschen 2005 ), Hydrochinae and Helophorinae. Th e monophyly of the hydrophiline-sphaeridiine lineage (Hydrophilidae s. Hansen 1991 ) is confi rmed with a bootstrap value of 86. Within this clade Berosus is placed as sister group of the remaining genera as in Beutel & Komarek (2004 ) (but see Archangelsky 2004 and Bernhard et al., 2006 ). A position of Spercheinae as the sister group of the remaining Hydrophiloidea was already suggested by Beutel (1999) based on apomorphic larval features not found in Spercheus but in all other hydrophiloid groups (including the histeroid families). Th is result suggests that a well developed, broad gula, the absence of nasale and adnasalia, a deep maxillary groove, an undivided cardo, a fully retained intramaxillary movability, a well developed lacinia, a normally developed M. craniolacinialis, and an oblique arrangement of Mm. tentoriocardinalis and -stipitalis may be indeed plesiomorphic features (Beutel 1994 , 1999), and not secondarily modifi ed features of Spercheinae. However, the basal placement of the subfamily was only found in the analysis using the modifi ed weighting scheme (Fig. 3) and does imply that the complex stigmatic atrium present in larvae of Spercheus , D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 13

Hydrochus , and the hydrophiline-sphaeridiine lineage has either evolved several times independently or became secondarily lost several times. Th e placement of the histeroid groups as subordinate taxon of Hydrophiloidea and not as sister group of a clade Hydrophilidae is in contrast to most recent studies (e.g., Hansen 1997a ; Archangelsky 1998 ; Beutel & Komarek 2004 ), but in agreement with a study based on features of the larval head (Beutel 1999). It is conceivable that the implied paraphyly of Hydrophilidae is an artefact due to the limited taxon sampling. Especially the inclusion of Horelophinae and Horelophopsinae may lead to diff erent results as presented here. Both groups are mainly characterised by plesiomorphic features compared to members of the hydrophiline-sphaeridiine lineage (Hansen 1991 ). Th e results of the combined Bayesian analysis (Fig. 4) confi rm the monophyly of Histeridae and the histeroid families (with Catops as sister taxon), of Hydrophilidae, of Helophorinae, of the hydrophiline-sphaeridiine lineage, with Berosus as sister group of the remaining genera, and the monophyly of Sphaeridiinae. In contrast to the parsimony analyses, Spercheinae are placed as sister group of the hydrophiline- sphaeridiine lineage in the majority rule consensus tree (98%) as suggested by Hansen (1991 ) in his preferred cladogram, and also by Archangelsky (1998 ) and Beutel & Komarek ( 2004 ). Th is is in agreement with the presence of a complex stigmatic atrium in the larvae (e.g., Archangelsky 1997 , 1998 ). However, this structure is also present in Hydrochinae (Archangelsky 1997 ), which do not form a clade with Spercheinae and Hydrophilidae s.str. in the trees obtained with the Bayesian analysis. Hydrochidae is placed as sister group of Georissidae as suggested by Hansen ( 1991 ), a position which is in contrast to all other recent studies (e.g., Archangelsky 1998 , 2008 ; Beutel & Komarek 2004 ; Beutel & Leschen 2005 ). Th e placement of Epimetopus as sister group of the spercheine-hydrophiline-sphaeridiine clade and Helophorinae as sister group of Hydrochinae + Georissinae is also not compatible with the results of other analyses (e.g., Hansen 1991 ; Archangelsky 1998 ; Beutel & Leschen 2005 ). In all analyes we carried out we obtained a branching pattern within the hydrophiline- sphaeridiine lineage with Hydrophilinae paraphyletic. Th is is in agreement with Beutel & Komarek ( 2004 ) and Bernhard et al. ( 2006 ) but in contrast to Hansen ( 1991 ) and a recent study by Archangelsky ( 2004 ). Clades comprising hydrophiline genera and a clade Sphaeridiinae are well supported in diff erent analyses ( Figs 1 – 4 ). Th ese results may be refuted or corroborated in future studies with a broader sampling of taxa of the hydrophiline-sphaeridiine lineage and including Horelophinae and Horelo- phopsinae as outgroup taxa.

Conclusions Even though the combined data set for Hydrophiloidea presented here is the most comprehensive ever analysed for the phylogenetic reconstruction of this group, distinctly diverging results in analyses with diﬀ erent data sets (morphological data/combined data), parameter settings (non weighing/weighing), and analytical methods 14 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

(parsimony Bayesian analyses) show that a reliable complete resolution of hydrophiloid relationships has not been achieved yet. Future analyses with a wider taxon sampling in the hydrophiline-sphaeridiinae lineage and still more information, especially on the morphology of immature stages, and more extensive molecular data may ﬁ nally solve the longstanding systematic problems of a much disputed group of Coleoptera. Future eﬀ orts should be directed towards little studied taxa, which potentially hold key positions in the phylogeny of Hydrophiloidea, especially Horelophinae and Horelophopsinae.

Acknowledgements We are greatly indebted to Andrew Short (University of Kansas) and Ronald Bellstedt (Museum der Natur, Gotha) for the gift of valuable material. Th e project was supported by the German Science Foundation (BE 1789/2-1 and BE 2349/1-1) which is also gratefully acknowldeged. We are also grateful for valuable comments made by two anonymous reviewers.

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Appendix A: Morphological characters for the analysis Adult characters 1. Orientation of head: (0) (sub)prognathous; (1) strongly defl exed. Strongly defl exed in Epimetopus, Georissus, Berosus and in Histeridae (Hansen 1991: char. 18, fi g. 291; Beutel & Leschen 2005). 2. Surface of head and pronotum (0) with conspicuous granules; (1) rugulose- punctate; (2) with even surface (e.g., Archangelsky et al. 2005: fi g. 10.1.1; Beutel & Leschen 2005: fi g. 1). Covered with distinct granules in Helophorus, Georissus, Epimetopus, and Hydrochus. Rugulose-punctate in Spercheus (Beutel et al. 2001: fi g. 1) and even in Hydrophilinae, Sphaeridiinae, Histeridae, Sphaerites and Catops. 3. Head abruptly narrowed in front of eyes (0) absent; (1) present (Hansen 1991; fi gs 182, 183). Narrowed abruptly in front of eyes in Georissus and Hydrochus, and also in Cercyon. Very strongly and abruptly narrowed in Histeridae, Sphaerites and Catops. 4. Anterior margin of clypeus (0) subtruncate to truncate; (1) forming a shelf with elevated margins (Hansen 1991: fi g. 186; Archangelsky et al. 2005: fi g. 10.1.1. E). Truncate in most taxa examined. With small blunt extensions (scored as 0) in Margarinotus. Forming a large, dosally concave shelf covering the labrum in Spercheus (Beutel et al. 2001: fi g. 1). 5. Frontoclypeal sutures on head (0) grooved; (1) indistinctly impressed (Hansen 1991; fi gs 179–209; Hansen 1997: char. 2, modifi ed; Archangelsky et al. 2005: fi g. 10.1.1). Indistinctly impressed in Hydrophilinae, Sphaeridiinae, Spercheus (Beutel et al. 2001: fi g. 1), Dendrophilus, Margarinotus, Sphaerites and Catops (distinctly impressed grooves in Margarinotus not homologous with frontoclypeal sutures). Distinctly impressed, grooved, sutures present in most subgroups of Hydrophilidae (e.g., Helophorinae; Beutel & Leschen 2005: fi g. 1A). 6. Eyes (0) distinctly protruding; (1) not or very slightly protruding. Distinctly protruding in Helophorus, Georissus, Hydrochus, Spercheus, Epimetopus, and Berosus. Almost completely integrated in the contour of the head capsule in Hydrophilinae and Sphaeridiinae, and also in Sphaerites (scored as 1). 7. Temples abruptly narrowing behind eyes (0) present; (1) absent (Hansen 1991: char. 17, fi gs 177, 179, 194, 196; Hansen 1997, char. 3, modifi ed, fi gs 11–14; Archangelsky et al. 2005: fi g. 10.1.1, Beutel & Leschen 2005, fi g. 1). Abruptly narrowing behind eyes, thus forming a distinct postocular sulcus in Helophorus, Hydrochus, Spercheus, and Epimetopus, and also in Catops. Constriction absent in most Hydrophilinae and Sphaeridiinae, in Georissus, and in Histeridae. Temples indistinct and not abruptly constricted in Sphaerites (scored as 1). 8. Hydrofuge pubescence of temporal region: (0) absent; (1) present; (2) parts of temporal region sparsely set with hairs. Absent in Epimetopus and Spercheus (Beutel et al. 2001: fi gs 1–3). Sparsely set with setae in Hydrochus, Georissus, Histeridae, Sphaerites and Catops. Dense in Helophorus and all Hydrophilinae and Sphaeridiinae. 18 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

9. Gula (0) forming a transverse triangle posteriorly, strongly narrowed and subparal- lel in anterior half; (1) strongly narrowed in entire length or gular sutures partly fused medially; (2) well developed with widely separated sutures (Hansen 1991: char. 23, modifi ed, fi gs 178, 191, 195, 199). Forming a short triangle posteriorly, with closely adjacent sutures in anterior portion in Helophorus, Hydrochus, Epimetopus, and Dendrophilus. Gula very small, with sutures partly fused in Georissus. Wide with well separated sutures converging anteriorly in Spercheus and all representatives of Hydrophilinae and Sphaeridiinae examined (Beutel & Leschen 2005, fi g. 3B), and also in Sphaerites. Sutures very widely separated and parallel in Margarinotus and Catops (scored as 2). 10. Labrum, partly concealed by clypeus (0) absent; (1) present. Partly retracted under the clypeus and thus partly concealed in representatives of Sphaeridiinae. Hansen 1991: char. 4. 11. Labrum, width/length ratio: (0) <2; (1) 2; (2) 2.5 (3) 3–4; (4) >4 (Archangelsky et al. 2005: fi g. 10.1.2). Width/length ratio of labrum less than 2 in Margarinotus; about 2 in Georissus, about 2.5 in Hydrochus, Berosus, and Dendrophilus, and more than 4 in Cercyon, Sphaeridium, and Catops. 12. Labrum, anterior margin (0) straight to slightly emarginate; (1) convexely rounded; (2) deeply excised (Archangelsky et al. 2005: fi g. 10.1.2). Convexely rounded in Georissus, Hydrochus, Berosus, and Dendrophilus. With a deep mesal emargination in Cercyon and Coelostoma. Straight or slightly emarginate in all other taxa examined. 13. Labrum, basally (0) widening; (1) narrowing; (2) anterior and posterior margin equally long (Hansen 1991: char. 1, fi gs 152–155; Archangelsky et al. 2005: fi g. 10.1.2). Distinctly narrowing basally in most representatives of Hydrophilinae (except Berosus) and Sphaeridiinae, in Spercheus, and less distinctly in Epimetopus and Dendrophilus. Anterior and posterior margins equally long in Margarinotus. Labrum widening towards posterior margin in Helophorus, Georissus, Hydrochus, Sphaerites, and very slightly in Catops (scored as 0). 14. Labrum lateral margins (0) set with spines or spine-like setae; (1) densely set with setae; (2) setation sparse or absent; (3) setation moderately dense (Hansen 1991: char. 2, modifi ed; Archangelsky et al. 2005: fi g. 10.1.2). Lateral margins set with spines in Helophorus, Georissus, and with spine-like setae in Hydrochus. Setae almost absent in Epimetopus and Catops. Setation sparse in most representatives of Hydrophilinae, but moderately dense in Berosus. Fringes dense in Spercheus, Sphaeridiinae, and in Dendrophilus, Margarinotus, and Sphaerites. 15. Ratio length of antennae/width of head ca. (0) 1/2; (1) 2/3; (2) 1; (3) >1 (Hansen 1991; Hansen 1997: fi gs 259–290). About 2/3 in most ingroup taxa examined and about 1/2 in Hydrochus, Spercheus, Georissus, Anacaena and Sphaeridium. Antenna approximately as long as width of head in Dendrophilus, Margarinotus, Sphaerites, and 2-3 x as long as head width in Catops. 16. Length ratio scapus/pedicellus ca. (0) 1–2; (1) 2–3; (2) >3 (Archangelsky et al. 2005: fi g. 10.1.1). Scapus equally long to twice as long as pedicellus in most ingroup taxa examined. More than three times as long in Epimetopus, Spercheus, D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 19

Sphaeridiinae, Histeridae, and Sphaerites. Slightly longer than pedicellus in Catops (scored as 0). 17. Scapus (0) straight, symmetrical; (1) curved, asymmetrical (Hansen 1997: fi g. 314, Archangelsky et al. 2005: fi g. 10.1.1). Straight, cylindrical, and sym- metrically shaped in Catops. Slightly curved and asymmetric in Georissus. Distinctly curved and of asymmetric shape in all other taxa examined. 18. Number of antennomeres: (0) 11; (1) 9; (2) 7 (Hansen 1997: char. 16, modifi ed). Number reduced (usually 9 antennomeres) in all taxa examined except for Histeridae, Sphaerites and Catops. Antenna composed of only seven antennomeres in Georissus, Hydrochus, Spercheus and Berosus. 19. Antennal club: (0) absent; (1) present (Hansen 1997: fi gs 59–71, 259–282, 314; Archangelsky et al. 2005: fi g. 10.1.1). Present in all ingroup taxa. Five-segmented in Ochthebius. Absent in Catops. 20. Cupula formed by antennomere 8: (0) absent; (1) present (Hansen 1991: char. 49, modifi ed, Hansen 1997: char. 18, modifi ed, fi gs 59–71; Archangelsky et al. 2005: fi g. 10.1.1). Cup-shaped antennomere 8 (morphologically) preceding antennal club present in most taxa under consideration. Absent in Dendrophilus and in Catops. Cupula formed by antennomere 6 in Ochthebius. 21. Respiratory function of antenna: (0) absent; (1) present (Hansen 1997: char. 15). With respiratory function in all representatives of Hydrophilidae and in the majority of Hydraenidae. 22. Pedicellus (0) glabrous; (1) setiferous (Hansen 1997: fi gs 60, 71; Archangelsky et al. 2005: fi g. 10.1.1). Setiferous in Spercheus and in Catops. 23. Cupula (0) glabrous; (1) setiferous (Hansen 1997: fi gs 59–71). Setiferous in Spercheus (Beutel et al. 2001: fi g. 3). 24. Antennal club (0) loose; (1) compact (Hansen 1991: char. 51, fi gs 222–232; Hansen 1997: fi gs 59–71). Compact in Epimetopus, Georissus, Cercyon, Sphaer- idium, Histeridae, and Sphaerites. 25. Mandible (0) projecting, exposed; (1) not projecting, largely concealed (Hansen 1997: fi gs 281, 282; Archangelsky et al. 2005: fi g. 10.1.1). Projecting in Histeridae and Sphaerites. Largely concealed by labrum and clypeus in all other taxa examined (lateral margins are partly visible in some taxa, e.g. Berosus, scored as 0). Retracted and largely concealed in Hydraenidae (scored as 1). 26. Lateral mandibular edge (0) nearly evenly rounded; (1) (almost) straight; (2) distinctly angulate; (3) with indentation; (4) lateral and anterior edges almost forming a right angle (Hansen 1991: char. 27, modifi ed, fi gs 168, 170; Archangelsky et al. 2005: fi g. 10.1.3). Evenly rounded in most taxa examined, including Catops. Mandible elongate, with evenly rounded lateral edges in Sphaerites. Lateral edges almost straight in Georissus. Distinctly angulate in Anacaena, Cymbiodyta, Enochrus, Helochares, and Cercyon. With indentation in Epimetopus, and strongly bent, forming a right angle with the anterior margin in Spercheus. 27. Mandibular apex (0) simply pointed; (1) bidentate; (2) tridentate (Hansen 1991, char. 26, modifi ed, fi gs 168, 170; Archangelsky et al. 2005: fi g. 10.1.3). Simply 20 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

pointed in Helophorus, Georissus, Cercyon, Sphaeridium, Margarinotus, and Catops. Bidentate in Spercheus, Epimetopus, in many representatives of Hydrophilinae and Sphaeridiinae, and in Dendrophilus. Tridentate in Hydrochus and Berosus. Left mandible tridentate and right mandible bidentate In Sphaerites (scored as 1). 28. Galea (0) oval shaped; (1) sickle shaped (Hansen 1991: char. 29, modifi ed; Archangelsky et al. 2005: fi g. 10.1.4A–D). Sickle shaped in Spercheus (Beutel et al. 2001: fi g. 7). Oval in the other ingroup taxa, Slightly elongate, with nearly oval shape in Catops (scored as 0). 29. Setae of galea (0) set in regular rows; (1) set in one row; (2) irregularly arranged (Hansen 1991: char. 32, modifi ed, fi gs 157, 158). Arranged in one row in Spercheus (Beutel et al. 2001). Irregularly arranged tuft of setae present in Berosus and Dendrophilus, Margarinotus, and Sphaerites (setae very long in the histeroid taxa). Irregular distribution of setae present Catops. 30. Ratio length of maxillary palpi/width of head (0) <1/3; (1) ca. 1/3; (2) ca. 1/2; (3) ca. 3/4; (4) ca. 1; (5) (Hansen 1991. chars 43 and 44 combined and modifi ed). Th e length ratio of maxillary palpi/width of head is 1/3 in Georissus, Margarinotus, Sphaerites and Catops, and about 3/4 in Berosus, Hydrobius and Cercyon. Th e maxillary palpi are about as long as width of head in many representatives of Hydrophilinae, and distinctly longer in Helochares. Th e maxillary palpi are very short in relation to the head width in Dendrophilus. 31. Maxillary palpomere 2, shape (0) almost straight, about as wide as palpomere 3; (1) distinctly infl ated, wider than palpomere 3; (2) slender, fl exed mesad; (4) slender, fl exed laterad (Hansen 1991, fi gs 156, 172–176; Archangelsky et al. 2005: fi g. 10.1.4A–D). Distinctly infl ated and wider than palpomere 3 in Anacaena and Sphaeridiinae. Flexed mesad in Helochares and laterad in Enochrus. Palpomeres very short and stout in Histeridae and Sphaerites, with palpomeres 2 and 3 about equally long (scored as 0). Palpomere 2 and 3 slender and about equally long in Catops. 32. Lateral margins of mentum (0) slightly converging; (1) distinctly converging; (2) almost straight (Hansen 1991: char 21 and 22, modifi ed; Archangelsky et al. 2005: fi g.10.1.4.E–K). Slightly converging in Helophorus, Anacaena, Cercyon and Dendrophilus. Strongly converging in Georissus, Sphaerites and Catops. 33. Width/length ratio of mentum (0) ca. 1; (1) 1–2; (2) >2 (Archangelsky et al. 2005: fi g. 10.1.4E–K). Lateral and anterior margins of the mentum almost equally wide in Helophorus and Georissus. Lateral margin 1–2× as long as anterior margin in most taxa examined. Distinctly wider than 2× in Spercheus and in Catops. 34. Anterior margin of mentum (0) broadly convex; (1) narrow; (2) (almost) straight; (3) angulately projecting; (4) bilobed (Archangelsky et al. 2005: fi g. 10.1.4E–K). Very narrow in Georissus. Narrow in Sphaerites. Nearly straight in Spercheus, straight in Catops, and angulate in Hydrochus. Mentum appearin bilobed, with very deep incision in Margarinotus. 35. Labial palpomere 2 (0) with one or few fi ne setae; (1) with a dense fringe of setae (Hansen 1991: chars. 37 and 38 combined and modifi ed, fi gs 161–166). Dense subapical fringe of setae present on labial palpomere 2 in Sphaeridiinae D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 21

(Archangelsky et al. 2005: fi g. 10.1.4J). Single seta present in most other ingroup taxa and in Catops. 36. Labial palpomere 3 set with (0) one to few setae or setae absent; (1) dense setae; (2) spines or spine-like setae (Hansen 1991: char. 42, modifi ed, fi gs 161–166). Set with spines in Georissus and with spine-like setae in Epimetopus (Archangelsky et al. 2005: fi g. 10.1.4F, G). Dense setation present in Helophorus. Setae absent in Histeridae, Sphaerites and in Catops. Palpomere 3 with one seta or few setae in all other taxa examined. 37. Shape of thorax: (0) elongate; (1) shorter than maximum width of metaventrite. Th orax (excl. metacoxae) shorter than maximum width of metaventrite in Histeridae, Sphaerites and most Hydrophilidae. More elongate in Hydrochus, Helophorus and Catops (Beutel & Komarek 2004, fi gs 1A, 7D). 38. Pronoto-elytral angle: (0) present; (1) absent or very indistinct. Absent or obsolete in Epimetopinae, Spercheus (Spercheinae), Georissus (Georissinae), Hydrophilinae, Sphaeridiinae, Histeridae, and Sphaerites. Distinct in Hydrochus, Helophorus, and Ochthebius. Angle indistinct in Catops. Hansen 1991: char. 52, fi gs 6–27. 39. Hydrofuge pubescence of ventral surface: (0) dense; (1) sparse; (2) absent. Usually present in Hydrophilidae nd Hydraenidae. Somewhat less dense in Cercyon (scored as 0) and sparse in Epimetopus. Sparse pubescence also present on the ventrites of Catops. Pubescence absent in Histeridae and Sphaerites. 40. Cervical sclerite: (0) present; (1) absent (Hansen 1997: char. 7, fi gs 26, 114). Pair of ventral cervical sclerites usually present in polyphagan beetles, but absent in Hydrochus and Georissus. 41. Surface structure of pronotum: (0) smooth or with indistinct lateral impressions; (1) with irregular granulation, tubercles and impressions; (2) with granulation and deeply impressed punctures (3) uneven and grooved; (4) with 5 longitudinal grooves; (5) with 7 distinct impressions (Hansen 1991: char. 53, modifi ed, fi gs 6–11, 18–149). Smooth pronotum with or without irregular punctuation present in Hydrophilinae, Sphaeridiinae, Histeridae, Sphaerites, and Catops. Irregular granulation, tubercles and impressions present in Epimetopus and bulges, granula and deeply impressed punctures in Georissus. Surface uneven and grooved in Spercheus. Five longitudinal grooves present in Helophorus, and seven distinct impressions in Hydrochus. 42. Shape of anterior pronotal margin: (0) without extension; (1) extension narrowed anteriorly; (2) extension widened anteriorly (Hansen 1991, fi gs 6–11). Antero- median pronotal extension present in Georissus and Epimetopus (Archangelsky et al. 2005, fi g. 10.5.1B, C). Narrowed anteriorly and extended as a shelf-like projection in Georissus, but widened anteriorly in Epimetopus. 43. Setiferous punctures, arranged in specifi c patterns (“systematic punctures”; Hansen 1991: char. 54, fi g. 150) on pronotum (0) absent; (1) present. Present in many genera of Hydrophilinae (except, e.g., Anacaenini). Absent in all other taxa under consideration. 44. Ridge below freely exposed posterior pronotal margin (=accessory ridge): (0) distinctly developed, equally curved; (1) absent (Hansen 1991: char. 56, modifi ed, 22 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

fi gs 240–242; Hansen 1997: char. 22, fi gs 93–98, 101–113; Archangelsky et al. 2005: fi g. 10.1.5). Absent in Catops. 45. Length of accessory ridge (0) narrow, less than 2/3 of posterior pronotal margin; (1) at least as wide as pronotum at posterior margin (Hansen 1991: char. 57, modifi ed). Broad in Helophorus, Epimetopus, Hydrochus, Georissus, and Histeridae, but narrow in Spercheus, most Hydrophilinae (except e.g., Berosus) and Sphae- ridiinae, and in Sphaerites. 46. Dentiform process of accessory ridge (0) absent; (1) present (Hansen 1991: char. 59, modifi ed, fi g. 241). Short blunt tooth present in Helophorus, Georissus, Spercheus and Hydrobius. 47. Subdivision of hypomeron into glabrous lateral and pubescent mesal part: (0) present, demarcated by ridge; (1) present, not demarcated by ridge; (2) absent. Hypomeron subdivided into glabrous and pubescent part in Hydrophilidae. Both parts very distinctly separated by a ridge in Helophorus, Epimetopus, Hydrochus, Georissus, and Spercheus. Ridge absent in Hydrophilinae and Sphaeridiinae. Subdivision absent in Histeridae, Sphaerites and Catops. 48. Groove for reception of the antennal club: (0) absent; (1) present, not limited by a distinct ridge; (2) present, limited by a distinct ridge (Hansen 1991: chars. 66, 67 combined, modifi ed, fi gs 238, 239, 241, 245). Hypomeral antennal grooves delimited by a distinct ridge present in Helophorus (Beutel & Komarek 2004, fi g. 1) and Georissus. Grooves weakly defi ned in Hydrochus, Epimetopus and Spercheus, and absent in most Hydrophilinae, Sphaeridiinae and Catops. Th e shape of the groove varies considerably. Th e anterolateral part of the prosternum forms a more or less extensive part of it in some representatives of Hydrophilidae (e.g., Cercyon) and this is also the case in Margarinotus (both scored as 2). 49. Apex of posterior hypomeral process: (0) blunt; (1) sharply pointed, long; (2) absent; (3) fused or connected with prosternal process; (4) sharply pointed, short (Hansen 1997: char. 25, modifi ed, fi gs 93–108; Archangelsky et al. 2005: fi g. 10.1.5). Apex of mesally directed process of posterior hypomeron free in all Hydrophilidae with the exception of Hydrochus (see char. 56). Short and blunt in most hydrophiline taxa examined. Short and pointed in Anacaena and absent in some sphaeridiines (e.g., Cercyon, Sphaeridium: process apically fused with internal postcoxal bridge). Hypomeral process long and sharply pointed apically in Sphaerites and Histeridae (Beutel & Komarek 2004, fi g. 5A). 50. Trochantinopleuron: (0) exposed, (1) not exposed. Base of trochantinopleuron exposed in Epimetopus, Spercheus (Beutel & Komarek 2004, fi g. 7A), Hydrophilinae, Sphaeridiinae, Sphaerites and Catops. Concealed by supracoxal lobes in Helophorus, Hydrochus (Beutel & Komarek 2004, fi g. 7B), Georissus and Histeridae. 51. Trochantinopleuron: (0) with moderately sized or small apical plate; (1) with extensive apical plate. Apical plate of trochantinopleuron usually extensive, but weakly developed in Epimetopus. Also small in Hydrochus, Histeridae and Sphaerites. 52. Notosternal suture: (0) well developed; (1) weakly developed (Beutel & Komarek 2004, fi g. 8). Indistinct in Hydrophilidae and in Catops. Very clearly impressed in Histeridae and Sphaerites. D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 23

53. Supracoxal lobes: (0) distinct; (1) indistinct. Usually well developed but strongly narrowed in Histeridae. 54. Precoxal portion of prosternum (0) well developed; (1) short; (2) extremely reduced (Hansen 1991: char. 60, modifi ed: Hansen 1997, fi gs 93–108, Archangelsky et al. 2005: fi g. 10.1.5). Th e precoxal portion of the prosternum is well developed in most representatives of Hydrophilidae and Dendrophilus. It is distinctly shortened in Epimetopus, Spercheus, Berosus, Cercyon, Catops and greatly reduced in Georissus. 55. Prosternal process: (0) absent; (1) present, narrow between procoxae; (2) wide between procoxae (Hansen 1997: char. 26, fi gs 93–108; Archangelsky et al. 2005: fi g. 10.1.5). Usually present and narrow between procoxae in Hydrophilidae and also narrow in Sphaerites. Very narrow in Catops and absent in Georissus (Archangelsky et al. 2005: fi g. 10.1.5C). Strongly broadened in Histeridae (Beutel & Komarek 2004: fi g. 4). 56. Apex of prosternal process: (0) not or slightly widened behind procoxae, not closing procoxal cavity externally; (1) distinctly widened behind procoxae, closing procoxal cavity (Hansen 1991: char. 61, fi gs 238–244, Hansen 1997: char. 27; Archangelsky et al. 2005: fi g. 10.1.5). Distinctly widened posteriorly in Hydrochus, forming an external postcoxal closure with the hypomeral process. 57. Procoxae: (0) narrowly separated, almost contiguous; (1) moderately separated; (2) widely separated. Usually narrowly separated or almost contiguous in Hydrophilidae and Catops. Very widely separated in Georissus, despite of the reduced condition of the prosternal process. Moderately separated in Histeridae. 58. Procoxal cavities: (0) internally closed (internal coxal bridge); (1) internally open (Hansen 1997, fi gs 93–108). Closed by a weakly sclerotized, almost hemispherical dorsal wall In Hydrophilidae, with a small dorsolateral opening for the passage of muscles (internal closure of the procoxal cavity) (Archangelsky et al. 2005: fi g. 10.1.5). Similar, weakly sclerotized but incomplete internal bridge present in Histeridae and Sphaerites (scored as 1). Complete internal bridge present in Catops. 59. Reinforced margin of internal coxal bridge (0) well developed; (1) weakly developed or absent. Usually present in Hydrophilidae, but absent in Epimetopus and Hydrochus (replaced by external bridge). Also absent in some representatives of Hydrophilinae and Sphaeridiinae (Anacaena, Cymbiodyta, Enochrus, Coelostoma), and in Catops. 60. Shape of anterolateral procoxal fi ssure: (0) narrow; (1) broad (Hansen 1997, char. 24, modifi ed, fi gs 101–108; Archangelsky et al. 2005: fi g. 10.1.5). Usually narrow in Hydrophilidae, but broadened and weakly defi ned from procoxal cavity in Epimetopus, Spercheus, Berosus, Cercyon, and also in Sphaerites and Catops (scored as inapplicable for taxa with completely concealed trochantinopleuron; see char. 50/1). 61. Procoxae: (0) cone-shaped; (1) transverse; (2) fused with trochanter; (3) almost globular (Hansen 1997: char. 57, modifi ed). Usually cone-shaped and protruding from coxal cavities to varying degrees in Hydrophilidae (Beutel & Komarek 2004, fi g. 9B) and in Catops. Slightly protruding in Hydrochus, strongly protruding in 24 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

e.g., Berosus, and very large in relation to prothorax in Eumetopus. Fused with trochanter and forming large plate-like structure in Georissus. Strongly transverse in most Histeridae and Sphaerites. 62. Profurcal arms: (0) short; (1) long. Usually arising separately from internal face of internal procoxal bridge in Hydrophilidae (origin shifted to mesal side of procoxal cavities in Berosus), short (= less than 0.3× vertical diameter of prothorax) and represented by simple plate-like extension. Enlarged in Margarinotus but rather short in Dendrophilus. Elongated and provided with extensions in Catops (0.5× vertical pronotal diameter). 63. Ventral pubescence on mesothorax (and metaventrite): (0) well developed; (1) pubescence largely or completely absent. Present in Helophorus, Hydrochus (extremely fi ne), Spercheus, Hydrophilinae and Sphaeridiinae. Sparse vestiture of hairs present in Epimetopinae and Catops. Surface characterised by distinct microstructure (iso- diametric meshes) in Georissus, but hairs almost completely lacking (scored as 1). Ventral surface largely or completely glabrous in Histeridae and Sphaerites. 64. Mesonotum: (0) well developed, large; (1) weakly sclerotized; (2) sclerotized, recuded in size. Well developed in most representatives of Hydrophilidae (Beutel & Komarek 2004, fi g. 1D) and in Catops. Poorly pigmented and partly semimembranous in Epimetopus, Hydrochus and Georissus. Well developed but reduced in size in Histeridae (in relation to anterior collar of mesothorax; Beutel & Komarek 2004, fi g. 4B, E). 65. Position of scutum and prophragma: (0) scutum and scutellum horizontal, prophragma vertical; (1) scutellum horizontal, scutum and prophragma vertical; (2) scutum and scutellum horizontal, prophragma only slightly defl ected. Scutum and scutellum more or less horizontal, with the prophragma in an almost vertical position and scarcely visible from above in Hydrophilidae, Sphaerites, and most other polyphagan beetles. Scutellum horizontal in Histeridae, but scutum and prophragma forming an almost vertical structure. 66. Shape of mesonotum: (0) roughly quadrangular; (1) roughly pentagonal; (2) roughly triangular. Roughly quadrangular in Helophorus (Beutel & Komarek 2004, fi g. 1D) and Georissus. Enlargement of scutellar shield (or presence of corresponding caudomedian extension of scutellum) results in pentagonal shape in Hydrophilinae, Sphaeridiinae, Hydrochus, Epimetopus, Spercheus, Sphaerites, and Catops. Mesonotum appears triangular in most Histeridae due to distinct elonga- tion of the posterolateral part of the scutellum. 67. Microstructure of mesonotum: (0) with distinct spines; (1) reticular or diagonal meshes; (2) smooth; (3) coarse punctures; (4) elongate meshes. Th e mesonotum is set with small but distinct spines in Helophorus and longer spines in Spercheus. A similar condition is also present in Catops (combined with horizontal meshes). Reticular or diagonal meshes are present in almost all other Hydrophilidae (surface smooth in Cercyon), sometimes combined with very sparse, short scattered spines (scored as 1). Elongate meshes, sometimes combined with stiff setae are characteristic for Histeridae. Coarse punctures are present in Sphaerites. D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 25

68. Size and position of scutellar shield: (0) small, not overlapping with scutum anteriorly, elevated; (1) large, elevated; (2) large, not elevated. Th e scutellar shield is small, elevated and variously shaped (ovoid, triangular, pentagonal) in Helophorus, Epimetopus, Hydrochus, Georissus and Histeridae. A large triangular scutellar shield is present in Spercheus, Hydrophilinae (elongated in Berosus), Sphaeridiinae and Sphaerites. A fairly large scutellar shield is present in Catops, but it lies on the same or on a slightly lower level than the scutum. 69. Scuto-scutellar suture (0) visible (1) not visible. Not or scarcely visible in Hydrophi- lidae, Histeridae and Catops. Impressed line present in Sphaerites. 70. Elytral length: (0) completely covering dorsal side of abdomen; (1) not completely covering dorsal side of abdomen. Shortened in Histeridae and Sphaerites. 71. Elytral striae or rows of punctures: (0) distinct rows of fi ne punctures; (1) impressed striae; (2) without striae, rows of punctures very indistinct or absent; (3) coarse punctures and longitudinal ridges. Striae present and distinctly impressed in Histeridae and Sphaerites, and also in Hydrobius and representatives of Megasternini (e.g., Cercyon). Striae present in apical half and very indistinctly impressed in Catops (scored as 1). Coarse serial punctures together with fl at ridges occur in Helophorus, Hydrochus, and Spercheus. Elytra with strong ridges in Georissus and Epimetopus, and distinct rows of comparatively fi ne punctures in representatives of Hydrophilinae and Sphaeridiinae (reduced in Anacaena, Cymbiodyta, Enochrus, Helochares, Coelostoma, and Sphaeridium). 72. “Systematic punctures” of elytra: (0) without “systematic punctures”; (1) with “systematic punctures” (Hansen 1991: “systematic punctures” char. 112; fi g. 150). Elytra with distinct longitudinal series of coarse setiferous punctures in the 3rd, 5th and 7th interstices (or corresponding positions in taxa without distinct interstices) in some genera of Hydrophilinae, (e.g., Berosini, Acidocerini). 73. Cuticular fold on ventral side of elytra: (0) absent; (1) present (Hansen 1991: char. 113, fi gs 333, 334). Fold on ventral surface of elytra serving as locking device present in Hydrochus and Georissus. 74. Subdivision of elytral epipleuron: (0) without distinct subdivision; (1) subdivision into glabrous, external “pseudepipleuron” and a mesal pubescent “epipleuron” (Hansen 1991 [fi g. 336], 1997: char. 65, modifi ed; Beutel & Komarek 2004, fi g. 9). Subdivided into 2 distinct portions in Hydrophilidae. “Epipleural part” sensu Hansen (1991) usually pubescent. Not subdivided in Histeroidea (only “pseudepipleuron”) and Catops. 75. Mesal part of epipleuron at base: (0) narrow; (1) wide. Usually narrow throughout in most subgroups of Hydrophilidae, but distinctly widened towards elytral base in Spercheus, Hydrophilinae (except Berosus) and Sphaeridiinae. 76. Demarcation of mesal part of epipleuron from “pseudepipleuron”: (0) ridge; (1) line (Hansen 1991: char. 116, modifi ed). Both epipleural parts separated by ridge in Helophorus (low), Epimetopus, Hydrochus, Georissus and Spercheus. Th in line (sometimes diffi cult to recognize or composed of small arcs) present in Hydrophili- nae and Sphaeridiinae. 26 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

77. Position of epipleuron: (0) horizontal; (1) oblique or almost vertical (Hansen 1991: char. 114, modifi ed). Anterior part more or less horizontal in most subgroups of Hydrophilidae. Oblique or almost vertical in Spercheus, Hydrophilinae and Sphaeridiinae (with few exceptions, e.g., Berosus and Cercyon). 78. Anterior collar of mesothorax: (0) narrow mesally, continuously widened towards pleural wing articulation; (1) entirely narrow; (2) mesally wide, widened towards pleural wing articulation; (3) mesally wide, narrowed towards pleural wing articulation; (4) absent or very indistinctly demarcated. Present in Hydrophilidae and Histeridae, but absent in Sphaerites. Collar rather narrow mesally and continuously widening towards pleural wing articulation in most hydrophilids. Narrow in Georissus (absent medially), Cercyon and Histeridae, and abruptly widened with a cranially defl ected lateral part in Epimetopus. Collar with wide median part and distinctly narrowing lateral part in Spercheus and Catops. 79. Shape of mesepimeron, dorsal horizontal part: (0) small, short; (1) strongly elongated; (2) with dorsal extension (Beutel & Komarek 2004, fi gs 1, 4, 7, 8; Archangelsky et al. 2005: fi g. 10.1.6). Sharply bent dorsally, thus forming distinct lateral edge of mesothorax at contact line with elytral epipleuron in almost all Hydrophilidae, Sphaerites and Catops. Distal part of dorsal portion distinctly extended in Georissus. Horizontal part strongly elongated in Histeridae in order to reach mesally shifted pleural wing articulation. 80. Contact of mesepimeron with mesocoxa: (0) wide; (1) narrow (Beutel & Komarek 2004, fi gs 1, 4, 7, 8; Archangelsky et al. 2005: fi g. 10.1.6). Mesepimeron broadly contacts mesocoxa (disjunct type) in most Hydrophilidae, Histeroidea and Catops. Contact narrow in Hydrochus. 81. Pleural suture: (0) distinct; (1) indistinct. Distinct in most subgroups of Hydrophilidae and in Catops, but indistinct in Helophorus, Hydrochus, Histeridae, and Sphaerites. 82. Anterior margin of mesoventrite: (0) narrowly reaching anterior mesothoracic margin; (1) not reaching anterior mesothoracic margin; (2) broadly reaching anterior mesothoracic margin (Archangelsky et al. 2005: fi g. 10.1.6). Mesoventrite narrowly reaching anterior mesothoracic margin in most ingroup taxa. Broad anteriorly in Hydrochus, Georissus, Cercyon, Histeroidea, and Catops. Not reaching anterior margin in Spercheus and some Hydrophilinae (e.g., Berosus, Anacaena). 83. Paramedian ridges of mesoventrite: (0) absent; (1) present. Variously shaped paramedian ridges of the mesoventrite present in Epimetopus and some Hydrophilinae and Sphaeridiinae (e.g., Cercyon). 84. Transverse ridge of mesoventrite: (0) absent; (1) present. External transverse ridge present in Helophorus and Georissus. 85. Shape of mesoventrite: (0) without anteromedian elevation; (1) with anteromedian elevation; (2) with horizontal posterior platform and vertical anterior part (Hansen 1991, fi gs 266–274). Elevated anteromedian part of mesoventrite present in Spercheus (rather indistinct) and many Hydrophilinae and Sphaeridiinae. Mesoventrite with quadrangular horizontal posteromedian platform and nearly D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 27

vertical anterior part in Histeridae and Sphaerites. Elevated part or platform absent in Catops. 86. Anapleural suture (0) well developed; (1) absent, mesoventrite fused with anepisternum; (2) indistinct. Present in most Hydrophilidae. Absent in Cercyon. Indistinct in Histeridae and Sphaerites. 87. Position of proximal part of anepisternum 2: (0) large, horizontal; (1) narrow, almost vertical. In an almost vertical position in Histeridae. 88. Dorsal portion of anepisternum 2: (0) narrowed toward pleural wing articulation; (1) conspicuously extended. Conspicuously extended towards pleural wing articulation in Georissus. 89. Mesotrochantin: (0) concealed; (1) exposed. Exposed in most taxa under consideration (coxa in refl ected position). Concealed by supracoxal lobe in Hydrochus, Georissus, Spercheus, and some Hydrophilinae (e.g., Anacaena), Histeridae, and Catops. Trochantin exposed by narrow fi ssure in Sphaerites. 90. Separation of mesocoxae: (0) narrowly separated; (1) broadly separated (Archangelsky et al. 2005: fi g. 10.1.6). Narrowly separated in most Hydrophilidae, Sphaerites and Catops (moderately separated in some Sphaeridiinae: e.g., Cercyon, Coelostoma). Very broadly separated in Georissus and Histeridae. 91. Mesofurca (0) well developed; (1) weakly developed. Usually well developed (Beutel & Komarek 2004: fi g. 2C), but highly reduced in Epimetopus, Georissus, and Histeridae. 92. Origin of mesofurcal arms: (0) arising separately; (1) with fused origin. Basally fused in Berosus, Coelostoma, and Sphaeridium. 93. Ridge connecting mesofurcal arms: (0) present; (1) present, disconnected from furcal base; (2) absent. Bases of mesofurcal arms usually connected by internal ridge between mesocoxae. Ridge absent in some Hydrophilinae and Sphaeridiinae (e.g., Berosus, Anacaena, Cercyon) and Catops. Disconnected from furcal base in Georissus. Not scored for taxa with fused origin of mesofurcal arms (char. 92.1). 94. Length of mesofurcal arms: (0) long, almost reaching or reaching pleural ridge; (1) short, ending c. halfway towards pleural ridge. Distinctly shortened in Epimetopus and some Hydrophilinae and Sphaeridiinae (Anacaena, Cymbiodyta, Enochrus, Helochares, Coelostoma, Cercyon, Sphaeridium). 95. Basal extension of mesofurcal arms: (0) present; (1) absent. Variously shaped basal extensions of mesofurcal arms present in some Hydrophilidae. Absent in Epimetopus, Cymbiodyta, Enochrus, and in Sphaeridiinae. 96. Apical extensions of mesofurcal arms: (0) present; (1) absent. Apical extensions of diff erent shape and size usually present and distinct in Hydrophilidae. Largely reduced in Epimetopus and Georissus. 97. Connection of mesofurcal arm with pleural ridge (0) distinctly separated from pleural ridge; (1) tightly connected but not fused; (2) connected with pleural ridge by short muscle. Not fused or closely connected with pleural ridge in most taxa examined. Both structures connected by a short muscle in Helophorus (Beutel & Komarek 2004, fi g. 2C) and Spercheus. Rigid connection present in Hydrobius. 28 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

98. Metanotum: (0) well developed; (1) weakly sclerotised. Generally well developed in Hydrophilidae (Beutel & Komarek 2004, fi g. 2E, F), but weakly sclerotized and poorly pigmented in Epimetopus, Cercyon and Catops. 99. Length of metanotum: (0) 2–3× as wide as long; (1) as wide as long; (2) more than 3× as wide as long. Two to three times as wide as long in most Hydrophilidae and Sphaerites. Distinctly elongated in Hydrochus (appoximately as wide as long) and Catops. Strongly widened in some Hydrophilinae (e.g., Berosus) and Sphae- ridiinae, and in Histeridae (almost 4x as wide as long). 100. Mesophragma: (0) present; (1) absent. Represented by two small median semilunar lobes distinctly demarcated from prescutum in most Hydrophilinae and the histeroid families. Absent in Epimetopus, Spercheus and some Hydrophilinae and Sphaeridiinae (e.g., Anacaena). 101. Anteromedian membranous area of the metanotum: (0) moderately to well developed; (1) narrow. Generally well developed, but distinctly narrowed in Histeridae. 102. Median sclerite of prescutum: (0) normally developed; (1) small, almost semilunar; (2) very large; (3) large and completely membranous. Fairly large, trapezi- form median sclerite of prescutum present in Helophorus and Hydrochus. Weakly developed, but large in relation to total size of prescutum in Catops. Strongly enlarged in Histeridae. Small and almost semilunar in most Hydrophilidae and Sphaeridiinae, and in Sphaerites. 103. Convexities of scutum: (0) distinct anterolateral bulges and ridges; (1) indistinct anterolateral bulges and ridges. Distinct anterolateral bulges and ridges separat- ing moderately convex muscle attachment areas present in most subgroups of Hydrophilidae (Beutel & Komarek 2004, fi g. 2E). Reduced in Epimetopinae, Spercheus, and many Hydrophilinae (e.g., Berosus, Anacaena, Cymbiodyta, Enochrus, Helochares, Hydrobius). Weakly developed in members of the histeroid families. 104. Anterior notal wing process (0) well developed; (1) weakly developed. Gener- ally well developed (Beutel & Komarek 2004, fi g. 2E) but indistinct in Ochthebius. 105. Lateral defl ected part of intrascutal suture: (0) long; (1) short; (2) indistinct. Transverse suture and corresponding internal ridge close to anterior scutal margin (“intrascutal suture”) usually present in Hydrophilidae. Lateral part defl ected caudally to varying degrees and also varying in length. Not reaching lateral margin of metanotum in Helophorus, Hydrochus, and some Hydrophilinae (e.g., Berosus). Very short to obsolete in Epimetopinae, Georissus, Spercheus, and some genera of Hydrophilinae and Sphaeridiinae (e.g., Hydrobius, Cercyon). 106. Length of alacristae: (0) reaching posterior margin of scutum; (1) not reaching posterior margin of scutum. Reaching posterior margin of scutum in all taxa examined with the exception of Georissus (Beutel & Komarek 2004, fi gs 2E, 4E). 107. Median ridge in depressed area between alacristae: (0) absent; (1) present. Present in depressed area between alacristae in Margarinotus, Sphaerites (short), and Sphaeridium (Beutel & Komarek 2004, fi gs 2E, 4E). D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 29

108. Scuto-scutellar suture: (0) crossing alacristae anterioly; (1) not crossing alacristae anteriorly. Crossing alacristae anteriorly in Helophorus, Hydrochus, some Hydrophilinae and Sphaeridiinae (e.g., Berosus, Cercyon, Sphaeridium), Sphaerites (indistinct laterally), and Catops. Dividing enclosed area into large scutellar portion and very small anterior scutal portion. 109. Width of metapostnotum: (0) narrow; (1) wide. Wide in Helophorus, Hydrochus, Berosus, and Sphaerites. Narrow in the other taxa under consideration. 110. Lateropostnotum (0) demarcated; (1) not demarcated from remaining metapostnotum. Metapostnotum divided into median and lateral portion (“lateropostnotum”) by distinct ridge in most Hydrophilidae and in Catops. Ridge absent in Epimetopus, Georissus, Spercheus, Histeridae and Sphaerites. 111. Lateral extension of lateropostnotum (0) not demarcated; (1) demarcated. Demarcated by suture in all representatives of Hydrophilidae examined. Suture absent in all other taxa under consideration. 112. Shape of metaventrite (0) evenly convex without well defi ned middle portion; (1) with well defi ned, raised middle portion; (2) with well defi ned, depressed middle portion (Beutel & Komarek 2004). Well defi ned, raised middle portion of metaventrite present in Histeridae (partim) and in most Hydrophilidae (except Helophorus and Hydrochus). Central part depressed in Georissus. 113. Anterior projection of metaventrite (0) present; (1) absent; (2) very broad (Hansen 1991, fi gs 268–284). Moderately broad anteriorly narrowing anteromedian projection present in most goups under consideration. Absent in Berosus and Catops (contiguous mesocoxae). Very broad projection present in Georissus and Histeridae. 114. Katepisternum (0) visible in total length; (1) paramesally concealed by metaventrite; (2) not recognizable. Exposed in its entire length in Helophorus (distinctly narrowed paramesally), Georissus, Sphaerites (indistinct transverse suture), Margarinotus (transverse suture indistinct laterally; Beutel & Komarek 2004, fi g. 4A, trr3) and in Catops. Paramesally concealed by preepisternal extension in Specheus, Epimetopus and in Hydrophilinae and Sphaeridiinae. Katepisternum not recognizable as separate sclerite in Hydrochus and Dendrophilus. 115. Metacoxal plates (0) absent; (1) present. Absent in all taxa under consideration. 116. Metacoxal separation (0) narrowly separated; (1) widely separated. Widely separated in Georissus and Histeridae, but almost adjacent or adjacent in the other taxa under consideration (Beutel & Komarek 2004, fi gs 4A, 7C, D). 117. Metacoxal cavities (0) almost parallel-sided or weakly narrowed laterally; (1) distinctly narrowed laterally. Distinctly narrowed laterally in Hydrochus and Georissus, and very strongly narrowed in Histeridae (Beutel & Komarek 2004, fi gs 4A, 7C, D, Archangelsky et al. 2005: fi g. 10.1.6). 118. Width of metacoxae: (0) distinctly broader than metaventrite, almost reaching lateral metathoracic margin; (1) not broader than metaventrite, distinctly separated from lateral metathoracic margin. Almost reaching lateral margin of metathorax in Hydrophilidae and Sphaerites. Distinctly separated from lateral margin in Histeridae and Catops. Beutel & Komarek 2004, fi gs 4A, 7C, D. 30 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

119. Metafurca, sclerotisation (0) distinctly sclerotised; (1) weakly sclerotised. Generally well developed and sclerotised in Hydrophilidae (Beutel & Komarek 2004, fi g. 5E). Weakly sclerotized and largely unpigmented in Epimetopus and Georissus. 120. Metafurcal base: (0) arising from basal stalk with narrow sulcus; (1) arising from basal stalk with broad sulcus; (2) repesented by common quadrangular plate; (3) arising from transverse ridge; (4) arising from common stalk without sulcus. Metafurca arises from common stalk with narrow sulcus in most subgroups of Hydrophilidae. Sulcus widened in Cercyon, Sphaeridium, and Sphaerites (with broad stalk). Absent in Catops. Entire metafurca represented by roughly quadrangular plate-like structure in Georissus. Arises from broad intercoxal portion of the katepisternum between metacoxal processus. Metafurcal arms arise from common transverse ridge between metacoxae in Histeridae. 121. Basal extension of metafurcal arms: (0) absent; (1) present. Variously shaped basal extensions of metafurcal arms present in most subgroups of Hydrophilidae and in Catops (large, triangular and medially fused in Helophorus, large triangular and paired in Hydrobius, rounded and large in Spercheus). Absent in Hydrochus, Epimetopus, Berosus, Cercyon, Sphaeridium and Dendrophilus. 122. Apex of metafurcal arms (0) enlarged; (1) not enlarged (Beutel & Komarek 2004). Slightly enlarged in Helophorus, Spercheus, Coelostoma, and Sphaerites. Very distinct apical extension present in most Hydrophilidae. Apical extensions absent in Hydrochus (metafurcal arms narrowed distally), Dendrophilus, and Catops. 123. Femora (0) cylindrical; (1) fl attened (Hansen 1991: char. 101, modifi ed). Nearly cylindrical in most representatives of Hydrophilidae. Distinctly fl attened in most Hydrophilinae (except Berosus) and Sphaeridiinae, in Histeridae, and in Catops. Less strongly fl attened in Sphaerites. 124. Shape of femora: (0) slender; (1) stout. Elongate and slender (length/width > 3) in most subgroups of Hydrophilidae and also in Sphaerites and Catops. Shortened (length/width ≤ 3) in Epimetopinae, in most Hydrophilinae and Sphaeridiinae (e.g., Anacaena, Cymbiodyta, Enochrus, Helochares, Hydrobius, Coelostoma, Cercyon, and Sphaeridium), and in Histeridae. 125. Femuro-tibial grooves: (0) absent; (1) present (Hansen 1991: chars 101, 102, modifi ed). Femoral grooves for reception of tibiae absent in most subgroups of Hydrophilidae, in Sphaerites, and in Catops. Usually present in Hydrophilinae (absent in Berosus) and Sphaeridiinae. Very distinct in Histeridae. 126. Dense pubescence on mesofemora: (0) absent; (1) present. Present on mesofemora (and more variably on metafemora) of Spercheus and many Hydrophilinae. Absent in Cercyon, Sphaeridium, Catops and in members of the histeroid families. 127. Shape of tibiae: (0) cylindrical; (1) fl attened (Hansen 1991: char. 103, modifi ed). Flattened in few taxa of Hydrophilinae (e.g., Anacaena), in all Sphaeridiinae examined, and in Histeridae. 128. Length of tibiae (0) elongate; (1) shortened, stout. Shortened in Epimetopus, Spercheus, some Hydrophilinae (e.g., Anacaena), Sphaeridiinae, and in Histeri- dae. Elongate in the other taxa under consideration. D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 31

129. Spines on meso- and metatibiae (0) distinct rows, not closely aggregated; (1) distinct rows, closely aggregated; (2) indistinct rows; (3) one row of short spines (Hansen 1991: char. 88, modifi ed). Equidistant rows of rather fi ne tibial spines present in most subgroups of Hydrophilidae. Two lateral rows more closely aggregated in Hydrophilinae and Sphaeridiinae, and very closely aggregated lateral rows also present on meso- and metatibiae of Margarinotus and Sphaerites. Tibial spines very weakly developed in Catops. One row of very short spines present in Dendrophilus. 130. Terminal spurs on tibiae: (0) weakly developed; (1) strong (Hansen 1997: char. 55, modifi ed). Weakly developed in most subgroups of Hydrophilidae. Well developed in Helophorus, Hydrophilinae and Sphaeridiinae, Histeridae, Sphaerites, and also in Catops. 131. Swimming hairs on dorsal face of middle- and hindlegs (0) absent; (1) present. Present on dorsal face of meso- and metatibiae (or/and on meso- and metatarsi) in some representatives of Hydrophilinae (e.g., Berosus, Hydrobius). Absent in all other taxa examined. 132. Ventral face of tarsi (0) without long hairs; (1) with long hairs; (2) entire surface pubescent. Long trichia in addition to short spines absent from ventral side of tarsi of most representatives of Hydrophilidae and Histeridae. Additional vestiture of long hairs present in Spercheus, some Sphaeridiinae (e.g., Cercyon, Coelostoma) and Sphaerites. Entire surface of tarsi pubescent in Catops. 133. Metatarsomere I: (0) shorter than tarsomere II; (1) longer than tarsomere II; (2) fused with tarsomere II. Almost always shorter than tarsomere II in Hydrophilinae, but longer in Sphaeridiinae, Histeridae, Sphaerites, and in Catops. Fused with metatarsomere II in Cymbiodyta. 134. Empodium (0) present, small; (1) absent; (2) large. Weakly developed and usually bisetose (sometimes polysetous) in most adults of Hydrophilidae and in Sphaerites. Absent in Hydrochus and distinctly enlarged in Spercheus and Berosus. Large and without setae in Histeridae. Empodium present but very small in Catops.

Characters of immature stages 135. Head: (0) subprognathous; (1) prognathous; (2) hyperprognathous. Prognathous in larvae of Hydrochus, Helophorus, Georissus, Epimetopinae (Richmond 1920; Costa et al. 1988), Synteliidae, Sphaeritidae and Histeridae (Newton 1991 [with some exceptions]; Beutel 1999), and in few larvae of Hydrophilinae (e.g., Berosus; Richmond 1920; Beutel 1999). Hyperprognathous in some larvae of Histeridae (e.g., Dendrophilus xavierae, Margarinotus sp.; Beutel 1999) and in almost all known larvae of Hydrophilinae and Sphaeridiinae (Richmond 1920; Böving & Henriksen 1938; Archangelsky 1997; Beutel 1999; prognathous in Berosus). Subprognathous in most groups of Staphylinoidea (Beutel & Molenda 1997: e.g., Leiodidae, Hydraenidae). 136. Labrum and clypeus: (0) connected by a membrane; (1) labrum and clypeus fused. Fused in all larvae of Hydrophiloidea (Richmond 1920; Costa et al. 1988; 32 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

Newton 1991). Movably connected with the clypeus in most groups of Staphy- linoidea (e.g., Leioididae, Hydraenidae, Agyrtidae; Beutel & Molenda 1997). 137. Adnasalia: (0) absent; (1) present. Present in Helophorus, Georissus, and Epime- topinae, in most larvae of Hydrophilinae and Sphaeridiinae (van Emden 1956; Richmond 1920; Böving & Henriksen 1938; Archangelsky 1997; Beutel 1999: fi gs 3-6), and in larvae of Synteliidae, Sphaeritidae and Histeridae (sometimes indistinct). Absent in Spercheus (Beutel 1999: fi g. 1) and in groups with movable labrum. Present but very small in Hydrochus rufi pes (Archangelsky 1997: fi g. 9C), but not recognisable in other species of Hydrochus (e.g., Richmond 1920) (coded as 0&1). 138. Armature of anterolateral clypeolabral margin: (0) without fi xed spines; (1) adnasalia with fi xed cuticular spines. Mesal edges of adnasalia set with fi xed cuticular spines in Georissus and Epimetopinae (van Emden 1956; Costa et al. 1988; Archangelsky 1997: fi gs 5B, 7A). 139. Gula or semimembranous gular region: (0) short and broad; (1) elongate and strongly narrowed gula or gular suture. Short and broad in Spercheus and Hydrochus (Richmond 1920; Beutel 1999: fi gs 7, 8), and in most groups of Staphylinoidea (Beutel & Molenda 1997). Narrow and elongated in other larvae of Hydrophiloidea (sutures still separated in larvae of Sphaeritidae; Nikitsky 1976; very indistinct in Histeridae; Beutel 1999). 140. Position of posterior tentorial pits: (0) immediately anterad of hind margin of head capsule; (1) central part of head capsule. Immediately anterad of hind margin of head capsule in Spercheus and Hydrochus (Beutel 1999: fi gs 7, 8). Anteromedian region of head capsule in other larvae of Hydrophiloidea (Beutel 1994; 1999: fi gs 9–12; Richmond 1920; Newton 1991; Beutel 1994, 1999). 141. Orientation of antenna: (0) anterolaterally directed with oblique articulating area; (1) anteriorly directed. Anteriorly directed with transverse articulating area in Hydrophiloidea (Richmond 1920; Böving & Henriksen 1938; Quennedey 1965; Newton 1991; Beutel 1994, 1999). Usually anterolaterally directed with oblique articulating area in Staphylinoidea (Beutel & Molenda 1997). 142. Location of antennal insertion: (0) anterolaterally; (1) on dorsal side of head capsule. Shifted dorsomesally in Epimetopinae, Hydrochus, Hydrophilinae and Sphaeridiinae (Richmond 1920; Böving & Henriksen 1938; Quennedey 1965; Costa et al. 1988; Archangelsky 1997; Beutel 1994, 1999). Lateral margin of antenna not contiguous with lateral margin of head capsule. 143. Mandibular mola: (0) present; (1) absent; (2) pseudomola. Mola absent in Hydrophiloidea. Conspicuous pseudomola developed at mesal mandibular base larvae of Hydrochus (Archangelsky 1997; Beutel; 1999). 144. Mandibular prostheca: (0) present; (1) absent. Absent in Hydrophiloidea, but present in some groups of Staphylinoidea (not in Leiodidae; Beutel & Molenda 1997). 145. Retinaculum: (0) simple; (1) bidentate, nearly symmetrical or symmetrical; (2) distinctly asymmetric. Small simple tooth distad of mola present in Hydraenidae and Leiodidae (Newton 1991; Beutel & Molenda 1997: fi gs 12, 14). Retinaculum D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 33

also simple in Spercheus, Syntelia, Sphaerites and Histeridae (Newton 1991; Beutel 1994, 1999: fi g. 12). Bidentate in Helophorus, Georissus (van Emden 1956; Archangelsky 1997), Epimetopinae (Costa et al. 1988; Archangelsky 1997 [with serrate edges and small proximal tooth]), Hydrochus (partim, coded as 0&1; Böving & Henriksen 1938; Archangelsky 1997) and most larvae of Hydrophilinae (Richmond 1920; Böving & Henriksen, 1938; Costa et al. 1988; Archangelsky 1997; slightly asymmetric in Cymbiodyta [coded as 1]; strongly asymmetric in Enochrus and Berosus). Strongly modifi ed and asymmetric in most larvae of Sphaeridiinae, but bidentate and symmetrical in Coelostoma and Dactylosternum (Costa et al. 1988; Böving & Henriksen, 1938). 146. Penicillus: (0) absent; (1) present. Present in Synteliidae, Sphaeritidae, Histeridae (Newton 1991) and Helophorus (Böving & Henriksen 1938; Archangelsky 1997). Elongated row of hairs present on proximomesal mandibular margin of larvae of Epimetopinae (Costa et al. 1988) (coded as 0). 147. Maxillary groove: (0) deep, with well developed articulating membrane; (1) maxillary groove partly reduced; (2) maxillary groove absent. Deep maxillary groove and a well developed articulating membrane present in Spercheus, Hydrochus and the outgroup taxa. Distinctly reduced in larvae of the remaining groups of Hydrophilidae and completely absent in larvae of Synteliidae, Histeridae and Sphaeritidae (Nikitsky 1976; Newton 1991; Beutel 1994, 1999). 148. Hinge between cardo and stipes: (0) fully developed; (1) distinctly reduced; (2) cardo fused with stipes or completely reduced. Movability between cardo and stipes fully retained in larvae of Spercheus and the outgroup taxa (Beutel & Molenda 1997). Hinge between both parts largely reduced and intra-movability strongy restricted in Hydrochus, Helophorus, Georissus, Hydrophilinae and Sphaeridiinae. Cardo and stipes fused or cardo absent in larvae of Synteliidae, Histeridae and Sphaeritidae (Newton 1991; Beutel 1999). 149. Cardo: (0) undivided or not present as a separate sclerite; (1) divided into at least two subcomponents. Divided into several sclerites in all groups of Hydrophilidae (Archangelsky 1997, 1998) with the exception of Spercheus (Beutel 1999). 150. Stipes: (0) mesally open proximally; (1) mesally closed. Mesally closed and tube- like in Synteliidae, Sphaeritidae, Histeridae, and Hydrophilidae (excluding Spercheus) (Beutel 1999). Proximal part of stipes mesally open and connected with lumen of the head capsule in Spercheus. Roughly semicircular in cross section, thus allowing the attachment of M. 18 on the ventral stipital surface (Beutel 1997). Also mesally open in the outgroup taxa (Beutel & Molenda 1997). 151. Lacinia: (0) strongly developed, hook-like: (1) small mesal protuberance; (2) absent. Lacinia strongly developed and hook-like in Spercheus and the outgroup taxa (Beutel 1994, 1999; Beutel & Molenda 1997). Absent in some larvae of Hydrochus (coded as 1&2) and in other groups of Hydrophiloidea (Newton 1991). Small mesal protuberance present in hydrochine larvae described by Archangelsky (1997) and Richmond (1920). 152. Insertion of palp: (0) laterally on stipes; (1) apically on stipes. Inserted laterally on stipes in Spercheus (Beutel 1999: fi gs 7, 17). Inserted apically in larvae of 34 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

other hydrophiloid groups. Stipes and palp together form an antenna-like structure. 153. Insertion of galea: (0) outer side of lacinia; (1) palpomere I; (2) galea absent or reduced to a small non-articulated process. Inserted on outer side of lacinia in the outgroup taxa. Shifted to mesal side of proximal palpomere in Hydrophiloidea (Beutel 1999: fi gs 7–10; Richmond 1920; Costa et al. 1988; Newton 1991). Galea absent in the larvae of Hydrochus examined. A non-articulated inner process of larvae of Hydrochus rufi pes (Archangelsky 1997) is not considered as a true outer lobe of the maxilla here (coded as 2). 154. Mentum: (0) distinct, inserted between maxillary grooves; (1) sclerotized, fairly large, shifted anteriorly; (2) mentum small, absent or completely membranous. Inserted between the maxillary grooves in the outgroup taxa (Newton 1991; Beutel & Molenda 1997), in Spercheus (fused with prementum), and in Hydrochus (Beutel 1999: fi gs 7, 8). Well developed, sclerotized, and shifted to the anterior margin of the head capsule in Helophorus, Epimetopinae, Georissus, Sphaeridiinae, and Hydrophilinae (Beutel 1999: fi gs 9, 10; Richmond 1920; Böving & Craighead 1931; Costa et al. 1988; Archangelsky 1998). Small and completely membranous in larvae of Synteliidae, Histeridae and Sphaeritidae (Beutel 1999: fi gs 11, 12; Newton 1991). 155. Anterior submentum: (0) enclosed by maxillary articulating membrane; (1) submentum completely integrated in the sclerotized ventral wall of the head capsule. Laterally enclosed by maxillary articulating membrane in the outgroup taxa and Spercheus (Beutel 1999: fi g. 7; Beutel & Molenda 1997), and in contrast to Archangelsky (1998, char. 32) also in larvae of Hydrochus (Beutel 1999: fi gs 8). Firmly integrated in the ventral wall of the head capsule in larvae of Synteliidae, Histeridae and Sphaeritidae (Beutel 1999: fi gs 11, 12; Newton 1991), Helophorus (Beutel 1999: fi g. 9), Epimetopinae (Costa et al. 1988), Georissus (van Emden 1956), and Hydrophilidae (Richmond 1920; Böving & Henriksen 1938; Moulins 1959; Quennedey 1965). 156. Submental suture: (0) absent; (1) present. Distinct V-shaped or almost straight suture present in Epimetopinae (Costa et al. 1988: pl. 23, fi g. 4), Georissus (Beutel 1999; van Emden 1956), Hydrophilinae and Sphaeridiinae (Beutel 1999: fi g. 10; Richmond 1920; Böving & Henriksen 1938; Moulins 1959; Quennedey 1965). 157. Dense preoral fi lter apparatus: (0) absent; (1) present. Present in larvae of Synteliidae, Histeridae and Sphaeritidae (Beutel 1999: fi g. 23; Newton 1991). 158. Stigmatic atrium: (0) absent; (1) present. Present in most larvae of Hydrophilinae and Sphaeridiinae (Hansen 1991; Böving & Henriksen 1938; Moulins 1959; Quennedey 1965), and also in Hydrochus and Spercheus (Richmond 1920; Hansen 1991; Archangelsky 1997, 1998). Absent in larvae of Berosus (Böving & Henriksen 1938) and all other larvae under consideration. 159. Tergal shield of abdominal segment VIII: (0) absent; (1) present. Sclerotized tergal shield of abdominal segment VIII present in larvae of Spercheus, Hydrochus (Richmond 1920; Hansen 1991), Hydrophilinae and Sphaeridiinae. D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 35

160. Eggs: (0) deposited uncovered; (1) upper side of single egg covered by a web; (2) eggs entirely covered by a web or enclosed in egg cases or cocoons. Upper side of single egg covered with secretions of silk glands in most larvae of Hydraenidae (see Hansen 1997b). Single egg (Hydrochus, Berosus [partim]) or several eggs deposited in egg cases or cocoons in larvae of Hydrophilidae (Richmond 1920; Spangler 1991; Hansen 1991, 1997a,b).

Appendix B. Character state matrix showing the distribution of character states (morphology)

Taxa/characters 12345678910111213

Catops sp. 0210110220 4 00 Ochthebius sp. 0210000120 2 00 Helophorus aquaticus 0000000100 3 00 H. arvernicus 0000000100 3 00 H. guttulus 0000000100 3 00 H. nivalis 0000000100 3 00 Georissus sp. 1010001210 1 10 Hydrochus carinatus 0010000200 2 10 Spercheus emarginatus 0101100020 3 01 Epimetopus sp. 1000000000 3 01 Anacaena globulus 0200111120 3 01 Berosus luridus 1200101120 2 10 Cymbiodyta marginella 0200111120 3 01 Enochrus testaceus 0200111120 3 01 E. quadripunctatus 0200111120 3 01 Helochares obscurus 0200111120 3 01 Hydrobius fuscipes 0200111120 3 01 Cercyon ustulatus 0210111121 4 21 Coelostoma orbiculare 0200111121 3 21 Sphaeridium bibustulatum 0200111121 4 01 Margarinotus brunneus 1210111220 0 02 Dendrophilus punctatus 1210111200 2 11 Sphaerites glabratus 0210111220 3 00 36 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

Taxa/characters 14 15 16 17 18 19 20 21 22 23 24 25 26

Catops sp. 230000001- - 00 Ochthebius sp. 2211110100 012 Helophorus aquaticus 0101111100 000 H. arvernicus 0101111100 000 H. guttulus 0101111100 000 H. nivalis 0101111100 000 Georissus sp. 0001211100 101 Hydrochus carinatus 0001211100 000 Spercheus emarginatus 1021211111 004 Epimetopus sp. 2121111100 103 Anacaena globulus 2001111100 002 Berosus luridus 3101211100 000 Cymbiodyta marginella 2101111100 002 Enochrus testaceus 2101111100 002 E. quadripunctatus 2101111100 002 Helochares obscurus 2101111100 002 Hydrobius fuscipes 2101111100 000 Cercyon ustulatus 1121111100 102 Coelostoma orbiculare 1121111100 000 Sphaeridium bibustulatum 1021111100 100 Margarinotus brunneus 1221011000 110 Dendrophilus punctatus 122101000- 110 Sphaerites glabratus 1221011000 110

Taxa/characters 27 28 29 30 31 32 33 34 35 36 37 38 39 Catops sp. 0 0 2 1 0 1 2 2 0 0 0 0 1 Ochthebius sp. 10220 20500000 Helophorus aquaticus 00020 00001000 H. arvernicus 00020 00001000 H. guttulus 00020 00001000 H. nivalis 00020 00001000 Georissus sp. 0 0 0 1 0 1 0 1 0 2 1 1 0 Hydrochus carinatus 20020 21300000 Spercheus emarginatus 11120 22200110 Epimetopus sp. 1 0 0 2 0 2 1 0 0 2 1 1 1 Anacaena globulus 10021 01000110 Berosus luridus 20230 21000110 Cymbiodyta marginella 10040 21000110 Enochrus testaceus 10044 21000110 E. quadripunctatus 10044 21000110 Helochares obscurus 10052 21000110 Hydrobius fuscipes 10030 21000110 Cercyon ustulatus 00031 01010110 Coelostoma orbiculare 10021 21010110 Sphaeridium bibustulatum 00021 21010110 Margarinotus brunneus 00210 21400112 Dendrophilus punctatus 10200 01000112 Sphaerites glabratus 10210 11100112 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 37

Taxa/characters 40 41 42 43 44 45 46 47 48 49 50 51 52

Catops sp. 00001- - 200011 Ochthebius sp. 00001- - 111010 Helophorus aquaticus 0400011020111 H. arvernicus 0400011020111 H. guttulus 0400011020111 H. nivalis 0400011020111 Georissus sp. 1210011020111 Hydrochus carinatus 1500010013101 Spercheus emarginatus 0300001010011 Epimetopus sp. 0120010010001 Anacaena globulus 0000000104011 Berosus luridus 0001010100011 Cymbiodyta marginella 0001000100011 Enochrus testaceus 0001000100011 E. quadripunctatus 0001000100011 Helochares obscurus 0001000100011 Hydrobius fuscipes 0001001100011 Cercyon ustulatus 0000000122011 Coelostoma orbiculare 0000000100011 Sphaeridium bibustulatum 0000000102011 Margarinotus brunneus 0000010221100 Dendrophilus punctatus 0000010201100 Sphaerites glabratus 0000000201000

Taxa/characters 53 54 55 56 57 58 59 60 61 62 63 64 65

Catops sp. 0110001101100 Ochthebius sp. 101001- 100020 Helophorus aquaticus 0010000-00000 H. arvernicus 0010000-00000 H. guttulus 0010000-00000 H. nivalis 0010000-00000 Georissus sp. 0200200-20110 Hydrochus carinatus 0011001-00010 Spercheus emarginatus 0110000100000 Epimetopus sp. 0110001100110 Anacaena globulus 0010001000000 Berosus luridus 0110000100000 Cymbiodyta marginella 0010001000000 Enochrus testaceus 0010001000000 E. quadripunctatus 0010001000000 Helochares obscurus 0010000000000 Hydrobius fuscipes 0010000000000 Cercyon ustulatus 0110000100000 Coelostoma orbiculare 0010001000000 Sphaeridium bibustulatum 0010000000000 Margarinotus brunneus 112011- -11121 Dendrophilus punctatus 102011- -10121 Sphaerites glabratus 011001- 11?100 38 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

Taxa/characters 66 67 68 69 70 71 72 73 74 75 76 77 78

Catops sp. 102101000-- -3 Ochthebius sp. 103101000-- -4 Helophorus aquaticus 0001030010000 H. arvernicus 0001030010000 H. guttulus 0001030010000 H. nivalis 0001030010000 Georissus sp. 0101030110001 Hydrochus carinatus 1101030110000 Spercheus emarginatus 1011030011003 Epimetopus sp. 1101030010002 Anacaena globulus 1111020011110 Berosus luridus 1111001010100 Cymbiodyta marginella 1111021011110 Enochrus testaceus 1111021011110 E. quadripunctatus 1111021011110 Helochares obscurus 1111021011110 Hydrobius fuscipes 1111011011110 Cercyon ustulatus 1211010011101 Coelostoma orbiculare 1111020011110 Sphaeridium bibustulatum 1111020001110 Margarinotus brunneus 240111000-- -1 Dendrophilus punctatus 240111000-- -1 Sphaerites glabratus 131011000-- -4

Taxa/characters 79 80 81 82 83 84 85 86 87 88 89 90 91

Catops sp. 0 0 0 2 0 0 0 0 0 0 0 0 0 Ochthebius sp. 0102000100001 Helophorus aquaticus 0010010000100 H. arvernicus 0010010000100 H. guttulus 0010010000100 H. nivalis 0010010000100 Georissus sp. 2002010001011 Hydrochus carinatus 0112000000000 Spercheus emarginatus 0001001000100 Epimetopus sp. 0000100000001 Epimetopus sp. 0001001000000 Berosus luridus 0001001000100 Cymbiodyta marginella 0000001000100 Enochrus testaceus 0000001000100 E. quadripunctatus 0000001000100 Helochares obscurus 0000001000100 Hydrobius fuscipes 0000001000100 Cercyon ustulatus 0002101100100 Coelostoma orbiculare 0000001000100 Sphaeridium bibustulatum 0000001000100 Margarinotus brunneus 1012002210011 Dendrophilus punctatus 1012002210011 Sphaerites glabratus 0012002200100 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 39

Taxa/characters 92 93 94 95 96 97 98 99 100 101 102 103 104

Catops sp. 0200001100000 Ochthebius sp. 0011001100111 Helophorus aquaticus 0000020000000 H. arvernicus 0000020000000 H. guttulus 0000020000000 H. nivalis 0000020000000 Georissus sp. 0100100000100 Hydrochus carinatus 0000000100000 Spercheus emarginatus 0010020010110 Epimetopus sp. 0001101010110 Anacaena globulus 0210000010110 Berosus luridus 1200000200110 Cymbiodyta marginella 0011000000110 Enochrus testaceus 0011000000110 E. quadripunctatus 0011000000110 Helochares obscurus 0010000000110 Hydrobius fuscipes 0000010000110 Cercyon ustulatus 0211001000100 Coelostoma orbiculare 1- 11000000100 Sphaeridium bibustulatum 1- 11000000100 Margarinotus brunneus 0000000201210 Dendrophilus punctatus 0000000201210 Sphaerites glabratus 0000000000110

Taxa/characters 105 106 107 108 109 110 111 112 113 114 115 116 117

Catops sp. 0 0 0 0 0 0 0 0 1 0 0 0 0 Ochthebius sp. 2000 110 00201 0 Helophorus aquaticus 0000 100 00000 0 H. arvernicus 0000 100 00000 0 H. guttulus 0000 100 00000 0 H. nivalis 0000 100 00000 0 Georissus sp. 1 1 0 1 0 1 0 2 2 0 0 1 1 Hydrochus carinatus 0000 100 00200 1 Spercheus emarginatus 1001 010 10100 0 Epimetopus sp. 1 0 0 1 0 1 0 1 0 1 0 0 0 Anacaena globulus 0001 001 10100 0 Berosus luridus 0000 101 11100 0 Cymbiodyta marginella 0001 001 10100 0 Enochrus testaceus 0001 001 10100 0 E. quadripunctatus 0001 001 10100 0 Helochares obscurus 0001 001 10100 0 Hydrobius fuscipes 1001 001 10100 0 Cercyon ustulatus 1000 001 10100 0 Coelostoma orbiculare 0001 001 10100 0 Sphaeridium bibustulatum 0010 001 10100 0 Margarinotus brunneus 0011 010 12001 1 Dendrophilus punctatus 0001 010 02201 1 Sphaerites glabratus 0010 110 00000 0 40 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41

Taxa/characters 118 119 120 121 122 123 124 125 126 127 128 129 130

Catops sp. 1 0 4 1 1 1 0 0 1 0 0 2 1 Ochthebius sp. 0000100000000 Helophorus aquaticus 0001000000001 H. arvernicus 0001000000001 H. guttulus 0001000000001 H. nivalis 0001000000001 Georissus sp. 0 1 2- - 00 0000 00 Hydrochus carinatus 0000100000000 Spercheus emarginatus 0001000010100 Epimetopus sp. 0 1 0 0 0 0 1 0 0 0 1 0 0 Anacaena globulus 0001011111111 Berosus luridus 0000000010011 Cymbiodyta marginella 0001011110011 Enochrus testaceus 0001011110011 E. quadripunctatus 0001011110011 Helochares obscurus 0001011110011 Hydrobius fuscipes 0001011110011 Cercyon ustulatus 0010011101111 Coelostoma orbiculare 0001011111111 Sphaeridium bibustulatum 0010011101111 Margarinotus brunneus 1031011101111 Dendrophilus punctatus 1030111101131 Sphaerites glabratus 0011010000011

Taxa/characters 131 132 133 134

Catops sp. 0 2 1 0 Ochthebius sp. 0030 Helophorus aquaticus 0001 H. arvernicus 0001 H. guttulus 0 0 0 1 H. nivalis 0001 Georissus sp. 0 0 0 0 Hydrochus carinatus 0 0 0 1 Spercheus emarginatus 0 1 0 2 Epimetopus sp. 0 0 0 0 Anacaena globulus 0 0 0 0 Berosus luridus 1 0 0 2 Cymbiodyta marginella 0030 Enochrus testaceus 0000 E. quadripunctatus 0000 Helochares obscurus 0000 Hydrobius fuscipes 1000 Cercyon ustulatus 0110 Coelostoma orbiculare 0110 Sphaeridium bibustulatum 0010 Margarinotus brunneus 0012 Dendrophilus punctatus 0012 Sphaerites glabratus 0110 D. Bernhard et al. / Insect Systematics & Evolution 40 (2009) 3–41 41

Taxa/larval characters 135 136 137 138 139 140 141 142 143 144 145 146 147 Catops 00000 00001000 Ochthebius 00000 00000000 Helophorus 11101 11011101 Georissus 11111 11011101 Hydrochus 1 1 0&1 0 0 0 1 1 2 1 0&1 0 0 Spercheus 11000 01011000 Epimetopus 11111 11111101 Anacaena 21101 11111101 Berosus 11101 11111201 Cymbiodyta 21101 11111101 Enochrus 21101 11111201 Helochares 21101 11111101 Hydrobius 21101 11111101 Cercyon 21101 11111201 Coelostoma 21101 11111101 Sphaeridium 21101 11111201 Margarinotus 21101 11111112 Dendrophilus 21101 11111112 Sphaerites 11101 11111112

Larvae could only be determined to genus level.

Taxa/larval characters 148 149 150 151 152 153 154 155 156 157 158 159 160

Catops 0 000 0 00 0000 0 0 Ochthebius 0 000 0 00 0000 0 1 Helophorus 1 112 1 11 1000 0 2 Georissus 1 112 1 11 1100 0 2 Hydrochus 1 1 1 1&2 1 2 0 0 0 0 1 1 2 Spercheus 0 000 0 10 0001 1 2 Epimetopus 1 112 1 11 1100 0 2 Anacaena 1 112 1 11 1101 1 2 Berosus 1 112 1 11 1100 1 2 Cymbiodyta 1 112 1 11 1101 1 2 Enochrus 1 112 1 11 1101 1 2 Helochares 1 112 1 11 1101 1 2 Hydrobius 1 112 1 11 1101 1 2 Cercyon 1 112 1 11 1101 1 2 Coelostoma 1 112 1 11 1101 1 2 Sphaeridium 1 112 1 11 1101 1 2 Margarinotus 2 112 1 12 1010 0 0 Dendrophilus 2 112 1 12 1010 0 0 Sphaerites 2 112 1 12 1010 0 0

Larvae could only be determined to genus level.