A newly detected exotic ambrosia beetle in Argentina: Euwallacea interjectus (Coleoptera: Curculionidae: Scolytinae)

An exotic species of ambrosia beetle (Coleoptera: Curculionidae: Scolytinae) of Asian origin has been detected recently in Argentina. Euwallacea interjectus (Blandford) has been collected infesting cultivated poplars in the Paraná Delta region. Identification was based on morphology and on DNA sequences of the COI gene. This finding adds to the increasing number of recent introductions of exotic ambrosia beetles into South America.Instituto de Recursos BiológicosFil: Landi, Lucas. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Recursos Biológicos; ArgentinaFil: Braccini, Celina Laura. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Recursos Biológicos; ArgentinaFil: Knížek, Milos. Forestry and Game Management Research Institute; República ChecaFil: Pereyra, Vanina Antonella. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; ArgentinaFil: Marvaldi, Adriana Elena. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentin

Unveiling the History of a Peculiar Weevil-Plant Interaction in South America: A Phylogeographic Approach to <i>Hydnorobius hydnorae</i> (Belidae) Associated with <i>Prosopanche americana</i> (Aristolochiaceae)

Interspecific interactions take place over both long and short time-frames. However it is not completely understood if the interacting-partners persisted, migrated, or expanded in concert with Quaternary climate and landscape changes. We aim to understand whether there is concordance between the specialist weevil Hydnorobius hydnorae and its parasitic host plant, Prosopanche Americana, in space and time. We aim to determine whether Prosopanche had already established its range, and Hydnorobius later actively colonized this rare resource; or, if both host plant and herbivore expanded their range concomitantly. We performed population genetic, phylogeographic and Bayesian diffusion analysis of Cytochrome B sequences from eighteen weevil localities and used paleodistribution models to infer host plant dispersal patterns. We found strong but uneven population structure across the range for H. hydnorae with weak signals of population growth, and haplotype network structure and SAMOVA groupings closely following biogeographic region boundaries. The ancestral areas for both Hydnorobius and Prosopanche are reconstructed in San Luis province within the Chaco Biogeographic province. Our results indicate a long trajectory of host-tracking through space and time, where the weevil has expanded its geographic range following its host plant, without significant demographic growth. We explore the past environmental changes that could underlie the boundaries between locality groups. We suggest that geographic dispersal without population growth in Hydnorobius could be enabled by the scarcity of the host plant itself, allowing for slow expansion rates and stable populations, with no need for significant demographic growth pulses to support range expansion.Facultad de Ciencias Naturales y Muse

Unveiling the History of a Peculiar Weevil-Plant Interaction in South America: A Phylogeographic Approach to <i>Hydnorobius hydnorae</i> (Belidae) Associated with <i>Prosopanche americana</i> (Aristolochiaceae)

Interspecific interactions take place over both long and short time-frames. However it is not completely understood if the interacting-partners persisted, migrated, or expanded in concert with Quaternary climate and landscape changes. We aim to understand whether there is concordance between the specialist weevil Hydnorobius hydnorae and its parasitic host plant, Prosopanche Americana, in space and time. We aim to determine whether Prosopanche had already established its range, and Hydnorobius later actively colonized this rare resource; or, if both host plant and herbivore expanded their range concomitantly. We performed population genetic, phylogeographic and Bayesian diffusion analysis of Cytochrome B sequences from eighteen weevil localities and used paleodistribution models to infer host plant dispersal patterns. We found strong but uneven population structure across the range for H. hydnorae with weak signals of population growth, and haplotype network structure and SAMOVA groupings closely following biogeographic region boundaries. The ancestral areas for both Hydnorobius and Prosopanche are reconstructed in San Luis province within the Chaco Biogeographic province. Our results indicate a long trajectory of host-tracking through space and time, where the weevil has expanded its geographic range following its host plant, without significant demographic growth. We explore the past environmental changes that could underlie the boundaries between locality groups. We suggest that geographic dispersal without population growth in Hydnorobius could be enabled by the scarcity of the host plant itself, allowing for slow expansion rates and stable populations, with no need for significant demographic growth pulses to support range expansion.Facultad de Ciencias Naturales y Muse

Comparative morphology of the larvae of the palm weevils Dynamis borassi (Fabricius) and Rhynchophorus palmarum (Linnaeus) (Curculionidae: Dryophthorinae): Two major pests of peach palms in the Neotropics

The morphology of the larvae of Dynamis borassi (Fabricius) and Rhynchophorus palmarum (Linnaeus) was compared, described and illustrated. A complete definition of subtribe Rhynchophorina at the larval stage was elaborated, based on mature and submature larvae, and characters of the first instar larvae are provided for the first time. Diagnostic characters to distinguish the larvae of D. borassi and R. palmarum are mainly from the epipharynx and maxillae, but the abdominal terminal plate also provides differential features that can aid in the identification. The characterization of both species at the larval stage is expected to be useful in the implementation of new control strategies in palm plantations in South America. For practical reasons, a comparative table is appended in Spanish to serve as a quick diagnostic guide for species identification.Facultad de Ciencias Naturales y Muse

A combined molecular and morphological approach to explore the higher phylogeny of Entimine weevils (Coleoptera: Curculionidae), with special reference to South American Taxa

The Entiminae are broad-nosed weevils constituting the most diverse subfamily of Curculionidae, with over 50 tribes. We performed Bayesian and Maximum Parsimony combined phylogenetic analyses with the main objective of testing higher-level relationships and the naturalness of the major Neotropical and Southern South American (Patagonia and Andes) tribes, including some members from other regions.We compiled a data matrix of 67 terminal units with 63 Entiminae species, as well as four outgroup taxa from Cyclominae, by 3522 molecular (from nuclear 18S rDNA and 28S rDNA, and mitochondrial 16S rDNA and COI gene sequences) and 70 morphological characters. The resulting trees recover a clade Entiminae with a monophyletic Cylydrorhinini and Premnotrypes branching off early. The tree resulting from parsimony analysis shows a clade of Leptopiini from the Australian region and another clade including taxa mainly distributed in the Palaearctic and Neotropical regions, but in the Bayesian tree the South American and Australian Leptopiini are grouped together. The mainly Palaearctic Entiminae (e.g., Brachyderini, Laparocerini, Otiorhynchini, Peritelini, Polydrusini, Phyllobiini and Sciaphylini) form a subclade separated from Southern Hemisphere taxa. Among the latter, the well-supported Naupactini are the sister group of the South American Tanymecini, excluding Platyaspistes, herein transferred to Leptopiini (new placement). Another well-justified clade is Eustylini-Geonemini, which also includes the enigmatic Galapagonotus, and the genus Artipus, thus corroborating its recent exclusion from Naupactini.Facultad de Ciencias Naturales y MuseoInstituto Multidisciplinario de Biología Celula

Comparative morphology of the larvae of the palm weevils Dynamis borassi (Fabricius) and Rhynchophorus palmarum (Linnaeus) (Curculionidae: Dryophthorinae): Two major pests of peach palms in the Neotropics

The morphology of the larvae of Dynamis borassi (Fabricius) and Rhynchophorus palmarum (Linnaeus) was compared, described and illustrated. A complete definition of subtribe Rhynchophorina at the larval stage was elaborated, based on mature and submature larvae, and characters of the first instar larvae are provided for the first time. Diagnostic characters to distinguish the larvae of D. borassi and R. palmarum are mainly from the epipharynx and maxillae, but the abdominal terminal plate also provides differential features that can aid in the identification. The characterization of both species at the larval stage is expected to be useful in the implementation of new control strategies in palm plantations in South America. For practical reasons, a comparative table is appended in Spanish to serve as a quick diagnostic guide for species identification.Facultad de Ciencias Naturales y Muse

A Newly Detected Exotic Ambrosia Beetle in Argentina : Euwallacea interjectus (Coleoptera: Curculionidae: Scolytinae)

An exotic species of ambrosia beetle (Coleoptera: Curculionidae: Scolytinae) of Asian origin has been detected recently in Argentina. Euwallacea interjectus (Blandford) has been collected infesting cultivated poplars in the Paraná Delta region. Identification was based on morphology and on DNA sequences of the COI gene. This finding adds to the increasing number of recent introductions of exotic ambrosia beetles into South America.Recientemente se detectó por primera vez en Argentina una especie exótica de escarabajo de Ambrosía (Coleoptera: Curculionidae: Scolytinae) de origen asiático. Euwallacea interjectus (Blandford) fue colectada afectando cultivos de álamo en la región del Delta del Río Paraná. Su identificación se basó en la morfología y en las secuencias de ADN del gen COI. Este hallazgo se suma al número cada vez mayor de introducciones recientes de escarabajos de Ambrosía exóticos en Sudamérica.Facultad de Ciencias Naturales y Muse

Phenotypic plasticity and the colonization of new habitats : A study of a colonial spider in the Chaco region and the Cerrado

In social animals, group prey capture could facilitate colonization of new areas with low resource availability. Parawixia bistriata is a colonial spider inhabiting seasonal dry forests and mesic habitats in South America. Individuals capture prey as a group, which allows individuals to broaden their foraging niche by incorporating large prey that cannot be subdued in solitary captures. P. bistriata exhibits two behavioural ecotypes a “dry” (plastic) ecotype which modifies individual’s tendency to capture prey in a group depending on food resources and a “wet” (fixed) ecotype, whose tendency to group prey capture is only modulated by the size of the prey but not by prey availability. By reconstructing the range expansion of the species using phylogeographic and species distribution modelling techniques, we indirectly examined whether group prey capture could have helped P. bistriata in colonization of low resource habitats. Based on cytochrome c oxidase subunit I gene genealogy, we found older populations in northern Cerrado in Brazil with more recent populations located further south in Dry and Humid Chaco in Argentina, with the latter being the most derived. Species distribution modelling for each ecotype suggests that suitable habitat for each ecotype started to overlap at some point during the Last Glacial Maximum (21 ky BP). These results suggest that P. bistriata expanded from northern Cerrado south to the Gran Chaco, being able to colonize mesic habitats at a later stage when individuals reached southern territories in the Chaco. This evidence is opposite to the idea that GPC facilitated P. bistriata colonization from mesic to harsher environments. However, plasticity in group prey capture could have been important to allow individuals to establish in mesic habitats by reducing the cost of group capture when under high resource levels.Facultad de Ciencias Naturales y Muse

The Beetle Tree of Life Reveals the Order Coleoptera Survived End Permain Mass Extinction to Diversify During the Cretaceous Terrestrial Revolution

Here we present a phylogeny of beetles (Insecta: Coleoptera) based on DNA sequence data from eight nuclear genes, including six single-copy nuclear protein-coding genes, for 367 species representing 172 of 183 extant families. Our results refine existing knowledge of relationships among major groups of beetles. Strepsiptera was confirmed as sister to Coleoptera and each of the suborders of Coleoptera was recovered as monophyletic. Interrelationships among the suborders, namely Polyphaga (Adephaga (Archostemata, Myxophaga)), in our study differ from previous studies. Adephaga comprised two clades corresponding to Hydradephaga and Geadephaga. The series and superfamilies of Polyphaga were mostly monophyletic. The traditional Cucujoidea were recovered in three distantly related clades. Lymexyloidea was recovered within Tenebrionoidea. Several of the series and superfamilies of Polyphaga received moderate to maximal clade support in most analyses, for example Buprestoidea, Chrysomeloidea, Coccinelloidea, Cucujiformia, Curculionoidea, Dascilloidea, Elateroidea, Histeroidea and Hydrophiloidea. However, many of the relationships within Polyphaga lacked compatible resolution under maximum-likelihood and Bayesian inference, and/or lacked consistently strong nodal support. Overall, we recovered slightly younger estimated divergence times than previous studies for most groups of beetles. The ordinal split between Coleoptera and Strepsiptera was estimated to have occurred in the Early Permian. Crown Coleoptera appeared in the Late Permian, and only one or two lineages survived the end-Permian mass extinction, with stem group representatives of all four suborders appearing by the end of the Triassic. The basal split in Polyphaga was estimated to have occurred in the Triassic, with the stem groups of most series and superfamilies originating during the Triassic or Jurassic. Most extant families of beetles were estimated to have Cretaceous origins. Overall, Coleoptera experienced an increase in diversification rate compared to the rest of Neuropteroidea. Furthermore, 10 family-level clades, all in suborder Polyphaga, were identified as having experienced significant increases in diversification rate. These include most beetle species with phytophagous habits, but also several groups not typically or primarily associated with plants. Most of these groups originated in the Cretaceous, which is also when a majority of the most species-rich beetle families first appeared. An additional 12 clades showed evidence for significant decreases in diversification rate. These clades are species-poor in the Modern fauna, but collectively exhibit diverse trophic habits. The apparent success of beetles, as measured by species numbers, may result from their associations with widespread and diverse substrates - especially plants, but also including fungi, wood and leaf litter - but what facilitated these associations in the first place or has allowed these associations to flourish likely varies within and between lineages. Our results provide a uniquely well-resolved temporal and phylogenetic framework for studying patterns of innovation and diversification in Coleoptera, and a foundation for further sampling and resolution of the beetle tree of life.Facultad de Ciencias Naturales y Muse

Morfología, biología e importancia filogenética de los estados inmaduros de la subfamilia <i>Brachycerinae</i> (Coleoptera: curculionidae)

La familia Curculionidae es la más diversa del reino animal y el conocimiento sobre los estados inmaduros y su biología es escaso comparado con el de los adultos. Los estados preimaginales, especialmente el estado de larva, constituyen una importante fuente de caracteres para reconstruir filogenias y lograr clasificaciones naturales. Asimismo, la identificación de todos ellos y la información sobre su biología son necesarios para estudios ecológicos y de manejo de plagas, ya que al tratarse de insectos fitófagos, numerosas especies son de importancia agrícola y el mayor daño a los cultivos es causado por las larvas. En esta tesis se tratan los Brachycerinae sensu lato, comúnmente conocidos como "gorgojos de rostro corto", las cuales presentan oviposición ectofítica. El principal propósito fue realizar un estudio comparativo de la morfología de los estados inmaduros y de la biología de estos gorgojos e integrar dicha información en un análisis filogenético. Se analizan e ilustran la morfología y caracteres del estado de huevo: forma, coloración, tamaño, estructura del corion, extracorion yprotección del huevo, tipo de posturas. Se brindan descripciones originales del huevo y la poistura de 14 especies representadas en Argentina. Se presenta una diagnosis larval de Curculionidae, se analizan e ilustran la morfología y caracteres del estado de larva: aspecto general y cutículas, áreas de la cabeza, setas y sensilas cefálicas, líneas frontales y epicraneal, endocarina, tentorio, cóndilos postoccipitales, varilla hipofaringeal, estemas, antenas, clípeo, labro, epifaringe, mandíbulas, maxilas, labio, áreas y setas de los segmentos del tórax, áreas y setas de los segmentos del abdomen, tipos de ápices abdominales, espiráculos. Se comparan distintos sistemas de términos empleados en sistemática de larvas y se eligen los que se consideran mas adecuados. Se analizan e ilustran la morfología y caracteres del estado de pupa: aspecto general, setas de la cabeza, tórax y abdomen, rostro, tecas mandibulares, patas, pterotecas primarias y secundarias, procesos posteriores, determinación del sexo. Se brinda una clave para el reconocimiento de pupas de seis especies representadas en Argentina; cuatro de ellas se caracterizan e ilustran por primera vez.Facultad de Ciencias Naturales y Muse