Phylogenetic revision of the genus Mesynodites Reichardt (Coleptera: Histeridae: Hetaeriinae)

Mesynodites is the largest genus within the exclusively inquilinous (social insect-associated) histerid beetle subfamily Hetaeriinae (Insecta: Coleoptera: Histeridae). The 44 described species are systematically revised, and new taxa are described based on newly discovered species and the results of a cladistic analysis. The work was based on available type specimens representing 42 species and approximately 2500 specimens of non-type material. Phylogenetic hypotheses were based on maximum parsimony analysis of 150 morphological characters derived from a selection of Mesynodites species and representatives of related genera. This analysis confirmed that, in its current concept, Mesynodites is not a monophyletic taxon. Species included currently in Mesynodites were scattered among 11 distinct lineages. As a result, in the revised sense, Mesynodites includes only nine species, two of which are of uncertain affinities (type specimens of these species were not located). Revision of Mesynodites species in the context of the phylogenetic analysis allowed numerous taxonomic changes to the Hetaeriinae. Presentation of those changes in this dissertation does not constitute formal publication. The following taxonomic changes are introduced: two new tribes are described and all genera of Hetaeriinae, excluding 12 genera of doubtful affinities, received tribal assignments; eight new genera and three new species are described; 37 new combinations and five new synonimities are established. The phylogenetic hypothesis of relationships within Mesynodites and allies (tribe Nymphisterini) provided some insight into evolution of host use in the lineage. This group evolved with army ants (Hymenoptera: Ecitoninae) and are known to occur with several species within the genera Eciton, Labidus, Neivamyrmex and Nomamyrmex. The ancestral host genus washypothesized to be either Eciton or Labidus. Contrary to previous opinions, species in several genera of Nymphysterini live with multiple host ant genera. Two separate host switches from army ants (Nomamyrmex and possibly Neivamyrmex) to leaf cutter ants Atta are hypothesized for species in Mutodites and Mesynodites. Analysis of host use and speciation revealed a trend of 1.5-2.5 times fewer species per strictly specialized (single host genus) guest genus, and this trend was consistent across different levels of analysis (Nymphysterini, all ecitophiles and all Hetaeriinae)

A revision of Megalocraerus Lewis, 1902 (Coleoptera, Histeridae: Exosternini)

The formely monotypic Neotropical genus Megalocraerus Lewis is revised to include five species, known from southeastern Brazil to Costa Rica: M. rubricatus Lewis, M. mandibularis sp. n., M. chico sp. n., M. madrededios sp. n., and M. tiputini sp. n. We describe the species, map their distributions, and provide a key for their identification. Their subcylindrical body form and emarginate mesosternum have previously hindered placement to tribe, although their curent assignment to Exosternini now appears well supported by morphological evidence. Nothing is known of the natural history of the species

A systematic revision of Baconia Lewis (Coleoptera, Histeridae, Exosternini)

Here we present a complete revision of the species of Baconia. Up until now there have been 27 species assigned to the genus (Mazur 2011), in two subgenera (Binhister Cooman and Baconia s. str.), with species in the Neotropical, Nearctic, Palaearctic, and Oriental regions. We recognize all these species as valid and correctly assigned to the genus, and redescribe all of them. We synonymize Binhister, previously used for a polyphyletic assemblage of species with varied relationships in the genus. We move four species into Baconia from other genera, and describe 85 species as new, bringing the total for the genus to 116 species. We divide these into 12 informal species groups, leaving 13 species unplaced to group. We present keys and diagnoses for all species, as well as habitus photos and illustrations of male genitalia for nearly all

A systematic revision of Baconia Lewis (Coleoptera, Histeridae, Exosternini)

Here we present a complete revision of the species of Baconia. Up until now there have been 27 species assigned to the genus (Mazur 2011), in two subgenera (Binhister Cooman and Baconia s. str.), with species in the Neotropical, Nearctic, Palaearctic, and Oriental regions. We recognize all these species as valid and correctly assigned to the genus, and redescribe all of them. We synonymize Binhister, previously used for a polyphyletic assemblage of species with varied relationships in the genus. We move four species into Baconia from other genera, and describe 85 species as new, bringing the total for the genus to 116 species. We divide these into 12 informal species groups, leaving 13 species unplaced to group. We present keys and diagnoses for all species, as well as habitus photos and illustrations of male genitalia for nearly all

A remarkable legion of guests: Diversity and host specificity of army ant symbionts

Tropical rainforests are among the most diverse biomes on Earth. While species inventories are far from complete for any tropical rainforest, even less is known about the intricate species interactions that form the basis of these ecological communities. One fascinating but poorly studied example are the symbiotic associations between army ants and their rich assemblages of parasitic arthropod guests. Hundreds of these guests, or myrmecophiles, have been taxonomically described. However, because previous work has mainly been based on haphazard collections from disjunct populations, it remains challenging to define species boundaries. We therefore know little about the species richness, abundance and host specificity of most guests in any given population, which is crucial to understand co‐evolutionary and ecological dynamics. Here, we report a quantitative community survey of myrmecophiles parasitizing the six sympatric Eciton army ant species in a Costa Rican rainforest. Combining DNA barcoding with morphological identification of over 2,000 specimens, we discovered 62 species, including 49 beetles, 11 flies, one millipede and one silverfish. At least 14 of these species were new to science. Ecological network analysis revealed a clear signal of host partitioning, and each Eciton species was host to both specialists and generalists. These varying degrees in host specificities translated into a moderate level of network specificity, highlighting the system's level of biotic pluralism in terms of biodiversity and interaction diversity. By providing vouchered DNA barcodes for army ant guest species, this study provides a baseline for future work on co‐evolutionary and ecological dynamics in these species‐rich host-symbiont networks across the Neotropical realm

Arthropod distribution in a tropical rainforest: tackling a four dimensional puzzle

Quantifying the spatio-temporal distribution of arthropods in tropical rainforests represents a first step towards scrutinizing the global distribution of biodiversity on Earth. To date moststudies have focused on narrow taxonomic groups or lack a design that allows partitioning of the components of diversity. Here, we consider an exceptionally large dataset (113,952 individuals representing 5,858 species), obtained from the San Lorenzo forest in Panama, where the phylogenetic breadth of arthropod taxa was surveyed using 14 protocols targeting the soil, litter, understory, lower and upper canopy habitats, replicated across seasons in 2003 and 2004. This dataset is used to explore the relative influence of horizontal, vertical and seasonal drivers of arthropod distribution in this forest. We considered arthropod abundance, observed and estimated species richness, additive decomposition of species richness, multiplicative partitioning of species diversity, variation in species composition, species turnover and guild structure as components of diversity. At the scale of our study (2km of distance, 40m in height and 400 days), the effects related to the vertical and seasonal dimensions were most important. Most adult arthropods were collected from the soil/ litter or the upper canopy and species richness was highest in the canopy. We compared the distribution of arthropods and trees within our study system. Effects related to the seasonal dimension were stronger for arthropods than for trees. We conclude that: (1) models of beta diversity developed for tropical trees are unlikely to be applicable to tropical arthropods; (2) it is imperative that estimates of global biodiversity derived from mass collecting of arthropods in tropical rainforests embrace the strong vertical and seasonal partitioning observed here; and (3) given the high species turnover observed between seasons, global climate change may have severe consequences for rainforest arthropods

Arthropod distribution in a tropical rainforest: tackling a four dimensional puzzle

Quantifying the spatio-temporal distribution of arthropods in tropical rainforests represents a first step towards scrutinizing the global distribution of biodiversity on Earth. To date most studies have focused on narrow taxonomic groups or lack a design that allows partitioning of the components of diversity. Here, we consider an exceptionally large dataset (113,952 individuals representing 5,858 species), obtained from the San Lorenzo forest in Panama, where the phylogenetic breadth of arthropod taxa was surveyed using 14 protocols targeting the soil, litter, understory, lower and upper canopy habitats, replicated across seasons in 2003 and 2004. This dataset is used to explore the relative influence of horizontal, vertical and seasonal drivers of arthropod distribution in this forest. We considered arthropod abundance, observed and estimated species richness, additive decomposition of species richness, multiplicative partitioning of species diversity, variation in species composition, species turnover and guild structure as components of diversity. At the scale of our study (2km of distance, 40m in height and 400 days), the effects related to the vertical and seasonal dimensions were most important. Most adult arthropods were collected from the soil/litter or the upper canopy and species richness was highest in the canopy. We compared the distribution of arthropods and trees within our study system. Effects related to the seasonal dimension were stronger for arthropods than for trees. We conclude that: (1) models of beta diversity developed for tropical trees are unlikely to be applicable to tropical arthropods; (2) it is imperative that estimates of global biodiversity derived from mass collecting of arthropods in tropical rainforests embrace the strong vertical and seasonal partitioning observed here; and (3) given the high species turnover observed between seasons, global climate change may have severe consequences for rainforest arthropods1012CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQSolVin-Solvay SA; Smithsonian Institution; Smithsonian Tropical Research Institute; United Nations Environment Programme; Smithsonian Institution; Smithsonian National Museum of Natural History; European Science Foundation (ESF); Global Canopy Programme; Czech Science foundation GACR grant; European Social Fund (ESF); Ministry of Education, Youth & Sports - Czech Republic; French National Research Agency (ANR); Research Council of Norway; Grant Agency of the Czech Republi

Record of Two Species of Histeridae New to the North American Fauna,Hypocacculus metallescens(Erichson) andAtholus confinis(Erichson), in Florida

Tishechkin, Alexey K. (2010): Record of Two Species of Histeridae New to the North American Fauna,Hypocacculus metallescens(Erichson) andAtholus confinis(Erichson), in Florida. The Coleopterists Bulletin 64 (3): 287-288, DOI: 10.1649/0010-065x-64.3.287.19, URL: http://dx.doi.org/10.1649/0010-065x-64.3.287.1

FIGURE 7 in A new species of Ptomaphagus (Appadelopsis) (Coleoptera: Leiodidae) from Great Smoky Mountains National Park, U.S.A.

FIGURE 7. Known distribution of Ptomaphagus merritti sp. n. (squares) and P. fumosus(Peck, 1978) (circles, filled—for historic records, open—for recent ATBI records) in the Great Smoky Mountains National Park.Published as part of <i>TISHECHKIN, ALEXEY K., 2007, A new species of Ptomaphagus (Appadelopsis) (Coleoptera: Leiodidae) from Great Smoky Mountains National Park, U.S.A., pp. 61-64 in Zootaxa 1478</i> on page 63, DOI: 10.11646/zootaxa.1478.1.6, <a href="http://zenodo.org/record/10088153">http://zenodo.org/record/10088153</a&gt