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We thank the Western Cape Nature Conservation Board (permit No. CN44-30-4229), the Cape Research Centre (South African National Parks, CRC/2019-2020/012-2012/V1) and Grootbos Private Nature reserve for authorization to collect specimens in the Western Cape province of South Africa.; International audience; The Cape Floristic Region in the Republic of South Africa is a well-recognized hotspot of biodiversity. Although this region is mostly known for its high level of plant diversity and endemicity, it also hosts an understudied and likely diverse arthropod fauna. Here we investigate the evolutionary history and timing of diversification of the apterous weevil genus Phlyctinus (Curculionidae: Entiminae), which is endemic to the coastal area and adjacent mountain ranges of the Cape floristic region and generally associated with sunflower plants (Asteraceae). We use a diverse array of molecular analyses (phylogenetic inference, molecular species delimitation and dating analyses) to analyse a novel molecular dataset of 202 weevil specimens (including 170 Phlyctinus sampled in 60 sites), and sequenced for two mitochondrial and four nuclear gene fragments. Phylogenetic and dating analyses indicate that the genus started diversifying in the late Miocene, with contrasting diversification dynamics for the three inferred clades, which present disjunct distributions. Host plant records and the lack of relatedness of species living in sympatry indicate that the diversification of Phlyctinus was predominantly driven by allopatric (geographic) speciation. We hypothesize that the interplay between topography and recurring cycles of coastline-habitat fragmentation resulting from sea level oscillations spurred the diversification of the most speciose clade, whereas in the two remaining clades populations likely remained connected thus hampering allopatric speciation. Interestingly, this pattern echoes with the role of sea level oscillations as an important driver of the radiation of several lineages in the coastline ecosystems of the Cape Floristic Region.

Aim We examine spatial and temporal patterns of diversification among flightless weevils in the genus Rhyncogonus (Curculionidae: Entiminae), with respect to their passive mode of dispersal by rafting or upon birds and the geological context of Pacific island archipelagos. Location Archipelagos and islands of the Pacific Ocean, especially the South Pacific and Hawaii. Methods Nuclear and mitochondrial DNA sequence data were used in Bayesian and maximum likelihood analyses to generate a phylogenetic hypothesis for all available species within the genus Rhyncogonus, plus representatives of other tribes in the subfamily Entiminae. Bayesian inference with molecular and geological calibration points was also used to estimate the age of major lineages of Rhyncogonus and infer the history of colonization. Results The genus Rhyncogonus has colonized all major archipelagos in the central Pacific, with multiple species occurring within nearly all archipelagos. The common ancestors of the genus were present in the central Pacific at least 15 Ma, probably first inhabiting islands now under water. Subsequent colonization and diversification across Oceania shows a pattern that is remarkably consistent with the geology of the region: the weevils, which likely disperse either by rafting on vegetation or on migratory birds, reached each island not long after its appearance. Main conclusions Though flightless, weevils in the genus Rhyncogonus have been remarkably effective at colonizing islands of the Pacific and appear to have colonized more remote islands via a series of less remote archipelagos. Although such a process of dispersal has been predicted, this study provides the first clear demonstration of the role of stepping-stones in the diversification of a lineage with passive dispersal.

Naupactini (Curculionidae: Entiminae) is a primarily Neotropical tribe of broad-nosed weevils with its highest genus and species diversity in South America. Despite several taxonomic contributions published during the last decades, the evolutionary history of Naupactini remains poorly understood. We present the first comprehensive phylogenetic analysis for this tribe based on a data matrix of 100 adult morphological characters scored for 70 species, representing 55 genera of Naupactini (ingroup) and four outgroups belonging to the entimine tribes Otiorhynchini, Entimini, Eustylini and Tanymecini. According to the most parsimonious tree Artipus does not belong to Naupactini; the genera with flat and broad antennae, formerly assigned to other entimine tribes, form a monophyletic group (Saurops (Curiades (Aptolemus (Platyomus)))) related to the clade (Megalostylus (Megalostylodes (Chamaelops Wagneriella))); and the genera distributed along the high Andes, Paramos and Puna form a natural group (Asymmathetes (Amphideritus (Leschenius (Amitrus (Obrieniolus (Melanocyphus Trichocyphus)))))), nested within a larger clade that includes Pantomorus, Naupactus and allied genera. Atrichonotus, Hoplopactus, Mimographus and Naupactus are not recovered as monophyletic. In order to address the taxonomic implications of our phylogenetic analysis, we propose the following nomenclatural changes: to transfer Artipus from Naupactini to Geonemini, to revalidate the genera Mimographopsis (type species M. viridicans), and to revalidate the genus Floresianus (type species F. sordidus). The evolution of selected characters is discussed. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:C8AA4388-A2F0-4E2D-889A-500BEA5A9DE1.

The sequential stages culminating in the publication of a morphological cladistic analysis of weevils in the Exophthalmus genus complex (Coleoptera: Curculionidae: Entiminae) are reviewed, with an emphasis on how early-stage homology assessments were gradually evaluated and refined in light of intermittent phylogenetic insights. In all, 60 incremental versions of the evolving character matrix were congealed and analysed, starting with an assembly of 52 taxa and ten traditionally deployed diagnostic characters, and ending with 90 taxa and 143 characters that reflect significantly more narrow assessments of phylogenetic similarity and scope. Standard matrix properties and analytical tree statistics were traced throughout the analytical process, and series of incongruence length indifference tests were used to identify critical points of topology change among succeeding matrix versions. This kind of parsimony-contingent rescoping is generally representative of the inferential process of character individuation within individual and across multiple cladistic analyses. The expected long-term outcome is a maturing observational terminology in which precise inferences of homology are parsimony-contingent, and the notions of homology and parsimony are inextricably linked. This contingent view of cladistic character individuation is contrasted with current approaches to developing phenotype ontologies based on homology-neutral structural equivalence expressions. Recommendations are made to transparently embrace the parsimony-contingent nature of cladistic homology.

A new species of Dichotrachelus is described from the Carnian Alps, Friuli-Venezia Giulia, north-eastern Italy (type locality: Moggio Udinese, Mount Sernio). The new species belongs to the D. luzei species group, previously known from Mt. Pasubio, Veneto, and Mt. Grintavec, Slovenia; its discovery in the Carnian Alps fills thus a broad gap in the distribution of this group. It is associated with Saxifraga caesia in limestone habitats; imagoes, apparently hatching in late summer, live in the small clumps of the host plants; some larvae were found among the roots. Additional specimens moderately distinct were found in the Julian Alps: taxonomic relationships between these and the type specimens of D. kahleni are discussed.

A new classification of Sitonini Gistel into ten genera is proposed, derived from a phylogenetic analysis based on morphology. Two subgenera of Sitona, Charagmus and Coelositona, are promoted to genus level. Sitona is restricted to the former nominotypical subgenus and redefined using apomorphies, and several species previously included in it are transferred to the genus Coelositona Gonzalez. The species composition of the genus Charagmus Schonherr is unchanged. Andriongen.n. is described (type species: Curculio regensteinensis Herbst, 1794). Catachaenus Schonherr, 1840 is synonymized with Eugnathus Schonherr, 1834 (syn.n.). Homalorhinus lutosus Hochhuth, 1847 is removed from Sitonini. The relationships represented by the new classification correspond with the evolution of Fabaceae (Leguminosae), mostly with the group of ‘temperate herbaceous tribes’ or Hologalegina. This group is divided into the sister clades, Loteae s.l. and IRLC (inverted repeat-lacking clade) – a clade well defined by the loss of a structural mutation in the genome of the chloroplast. Andrion does not feed on Hologalegina. Charagmus and Coelositona feed on species of Loteae s.l., whereas members of the genus Sitona feed on species in IRLC. This ability to feed on IRLC plants seems to have been a key trait that enabled the radiation of Sitona into more than 100 species. A key to the genera of Sitonini and illustrations of important morphological features are provided. A new structure is described from the internal sac, the ‘hamuli’. The variability of hamuli between the species of Sitonini is an important new tool in the taxonomy of this tribe. New combinations: Eugnathus circulus (Eydoux & Souleyet, 1839), E. mangarinicus (Voss, 1925), E. scintillans (Pascoe, 1874), E. sulcifrons (Heller, 1934), Charagmus gressorius (Fabricius, 1792), Ch. intermedius Kuster, 1847, Ch. griseus (Fabricius, 1775), Ch. cachectus Gyllenhal, 1834, Ch. stierliniReitter, 1903, Ch. variegatus (Fahraeus, 1840), Coelositona ribesi (Gonzalez, 1971), C. cambricus (Stephens, 1831), C. cinerascens (Fahraeus, 1840), C. limosus (Rossi, 1792), C. ocellatus (Kuster, 1849), C. latipennis (Gyllenhal, 1834), C. puberulus (Reitter, 1903), C. villosus (Allard, 1869), Andrion regensteinense (Herbst, 1794) and Anemeroides lutosus (Hochhuth, 1847).

Cyphopsis Roelofs (Entiminae: Naupactini) is herein considered a senior synonym of Miocyphus Hustache, including two species: C. clathrata Roelofs (syn. n. of C. jekelii Roelofs) and C. laticeps (Hustache) comb. n., ranging in Brazil and French Guiana. The genus characterizes by a truncate-conical pronotum with lateral tubercles, and a spermatheca with long horn-like nodulus, never seen in other Naupactini. This contribution includes a redescription of Cyphopsis and its two species, a dichotomous key, habitus photographs and line drawing illustrations of genitalia. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Two new species of the genus Eumyllocerus Sharp, 1896, of the subfamily Entiminae Schoenherr, 1823, are described from China. Eumyllocerus longisetus sp. n. may be distinguished from other species of the genus by its long bristle-like, erect setae on the intervals, each of which is longer than the width of the second interval, the setae arranged in double rows, and its shell-like, shiny, dense, metallic green scales. Eumyllocerus rotundicorpus sp. n. may be distinguished from any other Eumyllocerus species by its oval and inflated elytral shape, short stout metepisternum, small humeri, elytral setae shorter than 0.5 times the width of the second interval, the setae arranged in double rows, and its golden copper and pearl gray scales. The taxonomy of the genus is discussed. The two new species are described and habitus photographs and figures of diagnostic characters are provided. The type specimens of the new species are deposited in the Institute of Zoology, Chinese Academy of Sciences, Beijing, China (holotype and paratypes) and the Korean Entomological Institute, Korea University, Seoul, Korea (paratypes).

Myllocerus malignus Faust was described new to science from Korea in 1887. Since then, the species collected from Korea and Far-east Russia has been misidentified as Eumyllocerus gratiosus Sharp, E. filicornis (Reitter), or E. longulus Egorov et Zherikhin. A taxonomic review of Myllocerus malignus Faust (1887) with its synonymy and the clarification of sexual dimorphism is presented. As a results, Myllocerus viridiaureus Suvorov (1915) and Eumyllocerus longulus Egorov et Zherikhin (1990) are synonymized with Myllocerus malignus.

A taxonomic study of the genus Enaptorhinus G.R. Waterhouse in Korea is presented. Two species are recognized in Korea. Enaptorhinus sinensis G.R. Waterhouse is reported for the first time in Korea. A key, descriptions, and figures of diagnostic characters of known korean Enaptorhinus species are given.

A series of laboratory experiments was carried out with the main objective of contributing to the development of biosafety testing methods for transgenic plants or plants produced by other novel technologies. The adult stage of a New Zealand native weevil, Nicaeana cervina (Broun) (Coleoptera: Curculionidae: Entiminae), was used as a test insect as this has become well-adapted to introduced pasture species, feeding on both ryegrass [Lolium perenne L. (Poaceae)] and white clover [Trifolium repens L. (Fabaceae)]. Ryegrass plants used in experiments were infected with strains of the symbiotic endophytic fungi Neotyphodium lolii (Latch, M.J. Chr. & Samuels) and Epichloe festucae Leuchtm., Schardl & M.R. Siegel and included a transgenic endophyte, which was modified to eliminate production of the insect deterrent, peramine. Nicaeana cervina was exposed to these endophyte-infected plants along with endophyte-free ryegrass. Weevils were also exposed to white clover with high or low levels of cyanogens, and to white clover selections bred conventionally to contain high or low levels of crude protein. These bioassays were carried out sometimes over a series of time intervals, and weevil survival, feeding, and reproductive performance variables were measured. Nicaeana cervina survival was generally high, although feeding and oviposition were variable between experiments despite high replication in some cases. A summary of significant differences obtained across all experiments suggested that data on the proportion of weevils feeding and amounts of leaf material consumed were more often significantly different than treatment effects on survival or reproductive performance. A positive relationship between the proportion of weevils feeding and those ovipositing was found, suggesting that a 50% reduction in feeding would result in a 28% reduction in the proportion of weevils ovipositing. Power analysis using the range of values recorded for the variables measured indicated that for proportions of weevils surviving, feeding, or fecund, about 35-42 replicates would be required for a 40% difference in values. For measures of leaf consumption and numbers of eggs per female, fewer replicates were required for 95% power when these values were at the higher end of the range than when they were at the lower end of the observed range. The usefulness of the case study test insect and risk assessment protocols used for biosafety testing are discussed.