The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Gonzalo Halffter - One of the best experts on this subject based on the ideXlab platform.
-
a new species of american onthophagus latreille coleoptera Scarabaeidae scarabaeinae associated with rodent geomyidae burrows
Coleopterists Bulletin, 2018Co-Authors: Jose Luis Saanchezhuerta, Mario Zunino, Gonzalo HalffterAbstract:Onthophagus skelleyi Sanchez-Huerta, Zunino, and Halffter, new species, of the chevrolati species-group, hippopotamus line and complex, is described and illustrated. To the best of our knowledge, all of the species in this complex are associated with rodent (Geomyidae) burrows. The new species was found in northern Queretaro, Mexico, in the northeastern portion of the distribution area of the hippopotamus complex. The affinity of O. skelleyi with Onthophagus coproides Horn and Onthophagus hippopotamus Harold are discussed. An updated key to the species of the hippopotamus complex is also provided.
-
a new species of phanaeus macleay coleoptera Scarabaeidae scarabaeinae from los chimalapas oaxaca mexico
Coleopterists Bulletin, 2017Co-Authors: Victor Moctezuma, Gonzalo HalffterAbstract:Abstract Phanaeus (Notiophanaeus) zoque Moctezuma and Halffter, new species, of the endymion species-group, is described from the temperate forests of Los Chimalapas in Oaxaca, Mexico. The new species is illustrated and compared with the closely related Phanaeus endymion Harold. A diagnosis to separate it from related species is given, and its ecological aspects are discussed.
-
Dung beetle (Coleoptera: Scarabaeidae: Scarabaeinae) diversity in continuous forest, forest fragments and cattle pastures in a landscape of Chiapas, Mexico: the effects of anthropogenic changes
Biodiversity and Conservation, 2008Co-Authors: Darío Navarrete, Gonzalo HalffterAbstract:We studied the diversity of dung beetles in three different habitats in the Lacandona Forest, Chiapas, Mexico. We found a total of 49 species. Of these, 44 were in well-preserved forests (SC) within the limits of the Montes Azules Biosphere Reserve, 42 in fragmented forests (SF), and 13 in cattle pastures (PZ). These two latter habitats were part of a fragmented landscape. Even though the species richness between the two forest habitats is similar, there is a change in guild composition and structure. About 12% of the species were exclusively found in SC, while 4.1% and 2% were exclusive of SF and PZ respectively. β diversity was the most important element for overall diversity ( γ ), above that of the local richness ( α ). Within well-preserved forests, species composition changes substantially, even among neighboring sites. Species diversity within the landscape seems to depend on canopy coverage, soil temperature and geographic distance between sites. Functional groups vary with the habitat. Large-bodied, nocturnal species with specific requirements of soil temperature and compaction are more sensitive to anthropogenic changes. In cattle pastures there is a larger number of heliophilic species, with a higher percentage of small-bodied and roller beetles.
-
altitudinal variation of dung beetle Scarabaeidae scarabaeinae assemblages in the colombian andes
Global Ecology and Biogeography, 2005Co-Authors: Federico Escobar, Jorge M Lobo, Gonzalo HalffterAbstract:Aim We describe the changes in species richness, rarity and composition with altitude, and explore whether the differences in Scarabaeinae dung beetle composition along five altitudinal transects of the same mountain range are related to altitude or if there are interregional differences in these altitudinal gradients. Location Field work was carried out on the eastern slope of the eastern Cordillera, Colombian Andes, between Tama Peak to the north, in the Tama National Park (07°23′ N, 72°23′ W) and the San Miguel River (00°28′ N, 77°17′ W) to the south. Methods Sampling was carried out between February 1997 and November 1999 in five regions spanning elevation gradients. In each gradient, six sites were chosen at 250 m intervals between 1000 and 2250 m a.s.l. Results We found a curvilinear relationship between altitude and mean species richness, with a peak in richness at middle elevations. However, the diversity of dung beetle assemblages does not seem to be related to the interregional differences in environmental conditions. The number of geographically restricted species is negatively and significantly related to altitude, with geographically restricted species more frequent at low altitude sites. Ordination delimited the two main groups according to altitude: one with all the highest sites (1750–2250 m a.s.l.) and a second group with the remaining sites (< 1750 m a.s.l.). Analysis of species co-occurrence shows that these dung beetle assemblages seem to be spatially structured when all sites have the same probability of being chosen. In contrast, the spatial structure of species assemblages seems to be random when the probability of choosing any site is proportional to its altitude. Main conclusions The altitude of sites is the main factor that influences the diversity of these dung beetle assemblages. The peak in species richness at middle elevations, the higher number of geographically restricted species at lower altitudinal levels, and the compositional differences along these mountain gradients seem to result from the mixing at these altitudes of dung beetle assemblages that have different environmental adaptations and, probably, different origins. The relevance of altitude in these assemblages is related to the limited role of these Neotropical high altitude environments as centres of refuge and vicariance for a monophyletic group of warm-adapted species, for which the vertical colonization of these high mountain environments by lineages distributed at lower altitudes would have been very difficult.
François Génier - One of the best experts on this subject based on the ideXlab platform.
-
digitonthophagus balthasar 1959 taxonomy systematics and morphological phylogeny of the genus revealing an african species complex coleoptera Scarabaeidae scarabaeinae
Zootaxa, 2017Co-Authors: François Génier, Philippe MorettoAbstract:The taxonomy and systematics of the genus Digitonthophagus Balthasar (Coleoptera: Scarabaeidae: Scarabaeinae: Onthophagini) is revised. A detailed study of the male genitalia combined with external morphology suggests that the variability, previously recognized, for D. gazella is hiding a species complex within the Afrotropical region and the Arabian Peninsula. The current study recognizes 16 species; 13 from the Afrotropical region and Arabian Peninsula and three from the eastern portion of the Saharo-Arabian region and the continental Indomalayan region. Species are organized into six species groups based on the results of the morphology-based phylogenetic analysis. The following 12 species are described as new: D. aksumensis Genier new species; D. biflagellatus Genier new species; D. dilatatus Genier new species; D. eucatta Genier new species; D. falciger Genier new species; D. fimator Genier new species; D. namaquensis Genier new species; D. petilus Genier new species; D. sahelicus Moretto new species; D. uk s Genier new species; D. ulcerosus Genier new species; and D. viridicollis Genier new species. In order to stabilize nomenclature, lectotypes are designated for Scarabaeus bonasus Fabricius, 1775; Scarabaeus catta Fabricius, 1787, and Onthophagus gazella lusinganus d’Orbigny. A neotype is designated for Scarabaeus dorcas Olivier, 1789 whose status and synonymy need to be altered in order to clarify the status of Scarabaeus gazella auctorum, the widely introduced species with economic importance. A naming scheme is presented for the sclerites of the internal sac. External and male genitalia are illustrated and distribution maps are provided for each species.
-
digitonthophagus gazella auctorum an unfortunate case of mistaken identity for a widely introduced species coleoptera Scarabaeidae scarabaeinae onthophagini
Zootaxa, 2017Co-Authors: François Génier, Adrian L V DavisAbstract:At risk of committing entomological heresy, we question the identity of a dung-burying beetle species that originates from Africa and has been introduced first into Hawaii and subsequently to Australasia, North America, and South America (Fincher 1986; Edwards 2007; Noriega et al . 2010) for pasture improvement and biological control of dung-breeding flies (Waterhouse 1974; Bornemissza 1979). Under the name Onthophagus gazella (Fabricius 1787), it was the first species selected for introduction into Australia by the CSIRO Dung Beetle Project (Bornemissza 1976; Edwards 2007). Firstly, in 1968, a "tropical strain" was introduced from Hawaii where it had become established after introduction from Zimbabwe in 1957 (Markin & Yoshioka 1998). Later, after establishment of the CSIRO Dung Beetle Research Unit in Pretoria in 1970, a "cold" or "even rainfall strain" was introduced into Australia directly from South Africa (Bornemissza 1976) (even rainfall region = south coast of Eastern Cape). The species was subsequently introduced into the southern continental United States of America (Victoria County, Texas) from Hawaii (Montes de Oca & Halffter 1998) then elsewhere into southeastern and southwestern states from Hawaii and breeding colonies from Australia (Anderson & Loomis 1978). It has since expanded its range through Mexico, Central America, and the Caribbean to coastal Colombia (Kohlmann 1994; Noriega 2002; Noriega et al . 2006, 2011). Expansion of its range within central southern South America (Noriega et al . 2010) has been assisted by introductions into Brazil from the United States of America since the 1980s (Bianchin et al . 1998), and others into Venezuela and Chile (Vidaurre et al . 2008). More recently, it has been introduced into quarantine and field trials in New Zealand (Forgie et al . 2013) using individuals originating from the south coast of the Eastern Cape and Northwest Province of South Africa (S. Forgie, personal communication).
-
ateuchus cujuchi n sp a new inquiline species of scarabaeinae coleoptera Scarabaeidae from tuco tuco burrows in bolivia
Zootaxa, 2015Co-Authors: François GénierAbstract:In 2012, P. Skelley and J. Wappes were investigating the insect fauna of Ctenomys (Blainville, 1826) (Rodentia: Ctenomyidae) burrows at low elevation in Santa Cruz de la Sierra province, Bolivia. A number of beetles were extracted from this microhabitat and among them, 50 specimens belonging to the New World genus Ateuchus Weber from the subfamily Scarabaeinae (Coleoptera: Scarabaeidae). The specimens were submitted to the author for identification and did not match any currently described species. Although South American species of the genus Ateuchus are critically in need of a modern revision, it is considered important to describe this particular species as it is the first one recorded from mammal burrows in South America and it is easily distinguishable from all other known Ateuchus .
-
Innovative Bayesian and parsimony phylogeny of dung beetles (coleoptera, Scarabaeidae, scarabaeinae) enhanced by ontology-based partitioning of morphological characters.
PloS one, 2015Co-Authors: Sergei Tarasov, François GénierAbstract:Scarabaeine dung beetles are the dominant dung feeding group of insects and are widely used as model organisms in conservation, ecology and developmental biology. Due to the conflicts among 13 recently published phylogenies dealing with the higher-level relationships of dung beetles, the phylogeny of this lineage remains largely unresolved. In this study, we conduct rigorous phylogenetic analyses of dung beetles, based on an unprecedented taxon sample (110 taxa) and detailed investigation of morphology (205 characters). We provide the description of morphology and thoroughly illustrate the used characters. Along with parsimony, traditionally used in the analysis of morphological data, we also apply the Bayesian method with a novel approach that uses anatomy ontology for matrix partitioning. This approach allows for heterogeneity in evolutionary rates among characters from different anatomical regions. Anatomy ontology generates a number of parameter-partition schemes which we compare using Bayes factor. We also test the effect of inclusion of autapomorphies in the morphological analysis, which hitherto has not been examined. Generally, schemes with more parameters were favored in the Bayesian comparison suggesting that characters located on different body regions evolve at different rates and that partitioning of the data matrix using anatomy ontology is reasonable; however, trees from the parsimony and all the Bayesian analyses were quite consistent. The hypothesized phylogeny reveals many novel clades and provides additional support for some clades recovered in previous analyses. Our results provide a solid basis for a new classification of dung beetles, in which the taxonomic limits of the tribes Dichotomiini, Deltochilini and Coprini are restricted and many new tribes must be described. Based on the consistency of the phylogeny with biogeography, we speculate that dung beetles may have originated in the Mesozoic contrary to the traditional view pointing to a Cenozoic origin.
Federico Escobar - One of the best experts on this subject based on the ideXlab platform.
-
diversity and distribution of phanaeini coleoptera Scarabaeidae scarabaeinae in mexico
Zootaxa, 2017Co-Authors: Viridiana Lizardo, Federico Escobar, Octavio R RojassotoAbstract:In this study, we systematized available distribution data, obtained from biological databases and relevant literature, for Mexican species belonging to the tribe Phanaeini. The main objectives were to provide an overall description of the distribution records in biological collections, to detect potential sampling biases, to describe the seasonality of collections and to obtain species distribution models using the Desktop GARP algorithm. A total of 5,562 records, corresponding to 32 species in Mexico, were compiled, including the recently described Phanaeus zoque Moctezuma & Halffter, 2017. This compilation includes 784 unique collection records at 325 localities. These records were mainly distributed along the Trans-Mexican Volcanic Belt, the Sierra Madre Oriental and Sierra Madre Occidental mountain ranges and throughout the states of Chiapas and Veracruz. The Mexican High Plateau, the state of Tlaxcala and the Yucatan Peninsula are lacking in records. Distribution maps were created for species of three genera ( Phanaeus MacLeay, 1819 , Coprophanaeus Olsoufieff, 1924, and Sulcophanaeus Olsoufieff, 1924) and for 29 species present in Mexico. These species distributions are largely delimited by geomorphological features and vegetation types and coincide with expert descriptions of this tribe; some species show expanded distribution ranges. These maps provide a starting point for further analyses, the planning of future field studies, and the verification of possible new species in the Mexican territory.
-
global dung beetle response to tropical forest modification and fragmentation a quantitative literature review and meta analysis
Biological Conservation, 2007Co-Authors: Elizabeth Nichols, Trond Larsen, Sacha Spector, Adrian L V Davis, Federico Escobar, Mario Favila, Kevina VulinecAbstract:Although insects are crucial for maintaining ecosystem function, our understanding of their overall response to human activity remains limited. This is no less true of dung-burying beetles (Coleoptera: Scarabaeidae: Scarabaeinae), which provide a suite of critical ecosystem functions and services, yet but face multiple conservation threats, particularly from landscape conversion. Here we use a review and meta-analysis to synthesize the current knowledge concerning response to tropical forest modification and fragmentation of dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae). For every modified habitat type and individual forest fragment across 33 studies, we calculated six dung beetle community parameters, standardized relative to intact tropical forest. We organized modified habitats along an approximate disturbance gradient ranging from selectively logged, late and early secondary forest, through agroforestry, tree plantations, to annual crops, cattle pastures and clear-cuts. Secondary forests, selectively logged forest and agroforests supported rich communities with many intact forest species, while cattle pastures and clear-cuts contained fewer species overall with few forest-dwelling species. Abundance generally declined with increasing modification, but was quite variable. Communities in open habitats were often characterized by hyper-abundance of a small number of small-bodied species, leading to low evenness. Across fragmentation studies, dung beetle species richness, abundance and evenness declined in smaller forest fragments. Richness and abundance sometimes declined in more isolated fragments, although this response appeared to depend on matrix quality. Across both habitat modification and fragmentation studies, geographic location and landscape context appeared to modify dung beetle response by influencing the available pool of colonists. We discuss potential underlying mechanisms and conclude with recommendations for management and conservation and for future research.
-
altitudinal variation of dung beetle Scarabaeidae scarabaeinae assemblages in the colombian andes
Global Ecology and Biogeography, 2005Co-Authors: Federico Escobar, Jorge M Lobo, Gonzalo HalffterAbstract:Aim We describe the changes in species richness, rarity and composition with altitude, and explore whether the differences in Scarabaeinae dung beetle composition along five altitudinal transects of the same mountain range are related to altitude or if there are interregional differences in these altitudinal gradients. Location Field work was carried out on the eastern slope of the eastern Cordillera, Colombian Andes, between Tama Peak to the north, in the Tama National Park (07°23′ N, 72°23′ W) and the San Miguel River (00°28′ N, 77°17′ W) to the south. Methods Sampling was carried out between February 1997 and November 1999 in five regions spanning elevation gradients. In each gradient, six sites were chosen at 250 m intervals between 1000 and 2250 m a.s.l. Results We found a curvilinear relationship between altitude and mean species richness, with a peak in richness at middle elevations. However, the diversity of dung beetle assemblages does not seem to be related to the interregional differences in environmental conditions. The number of geographically restricted species is negatively and significantly related to altitude, with geographically restricted species more frequent at low altitude sites. Ordination delimited the two main groups according to altitude: one with all the highest sites (1750–2250 m a.s.l.) and a second group with the remaining sites (< 1750 m a.s.l.). Analysis of species co-occurrence shows that these dung beetle assemblages seem to be spatially structured when all sites have the same probability of being chosen. In contrast, the spatial structure of species assemblages seems to be random when the probability of choosing any site is proportional to its altitude. Main conclusions The altitude of sites is the main factor that influences the diversity of these dung beetle assemblages. The peak in species richness at middle elevations, the higher number of geographically restricted species at lower altitudinal levels, and the compositional differences along these mountain gradients seem to result from the mixing at these altitudes of dung beetle assemblages that have different environmental adaptations and, probably, different origins. The relevance of altitude in these assemblages is related to the limited role of these Neotropical high altitude environments as centres of refuge and vicariance for a monophyletic group of warm-adapted species, for which the vertical colonization of these high mountain environments by lineages distributed at lower altitudes would have been very difficult.
Mario Favila - One of the best experts on this subject based on the ideXlab platform.
-
ecological functions and ecosystem services provided by scarabaeinae dung beetles
Biological Conservation, 2008Co-Authors: Elizabeth Nichols, Trond Larsen, Sacha Spector, Julio Louzada, Sandra Amezquita, Mario FavilaAbstract:Clear understanding of the links between ecological functions and biodiversity is needed to assess and predict the true environmental consequences of human activities. Several key ecosystem functions are provided by coprophagous beetles in the subfamily Scarabaeinae (Coleoptera: Scarabaeidae), which feed on animal excreta as both adults and larvae. Through manipulating feces during the feeding process, dung beetles instigate a series of ecosystem functions ranging from secondary seed dispersal to nutrient cycling and parasite suppression. Many of these ecological functions provide valuable ecosystem services such as biological pest control and soil fertilization. Here we summarize the contributions of dung beetles to nutrient cycling, bioturbation, plant growth enhancement, secondary seed dispersal and parasite control, as well as highlight their more limited role in pollination and trophic regulation. We discuss where these ecosystem functions clearly translate into ecosystem services, outline areas in critical need of additional research and describe a research agenda to fill those gaps. Due to the high sensitivity of dung beetles to habitat modification and changing dung resources, many of these ecological processes have already been disrupted or may be affected in the future. Prediction of the functional consequences of dung beetle decline demands functional studies conducted with naturally assembled beetle communities, which broaden the geographic scope of existing work, assess the spatio-temporal distribution of multiple functions, and link these ecosystem processes more clearly to ecosystem services.
-
global dung beetle response to tropical forest modification and fragmentation a quantitative literature review and meta analysis
Biological Conservation, 2007Co-Authors: Elizabeth Nichols, Trond Larsen, Sacha Spector, Adrian L V Davis, Federico Escobar, Mario Favila, Kevina VulinecAbstract:Although insects are crucial for maintaining ecosystem function, our understanding of their overall response to human activity remains limited. This is no less true of dung-burying beetles (Coleoptera: Scarabaeidae: Scarabaeinae), which provide a suite of critical ecosystem functions and services, yet but face multiple conservation threats, particularly from landscape conversion. Here we use a review and meta-analysis to synthesize the current knowledge concerning response to tropical forest modification and fragmentation of dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae). For every modified habitat type and individual forest fragment across 33 studies, we calculated six dung beetle community parameters, standardized relative to intact tropical forest. We organized modified habitats along an approximate disturbance gradient ranging from selectively logged, late and early secondary forest, through agroforestry, tree plantations, to annual crops, cattle pastures and clear-cuts. Secondary forests, selectively logged forest and agroforests supported rich communities with many intact forest species, while cattle pastures and clear-cuts contained fewer species overall with few forest-dwelling species. Abundance generally declined with increasing modification, but was quite variable. Communities in open habitats were often characterized by hyper-abundance of a small number of small-bodied species, leading to low evenness. Across fragmentation studies, dung beetle species richness, abundance and evenness declined in smaller forest fragments. Richness and abundance sometimes declined in more isolated fragments, although this response appeared to depend on matrix quality. Across both habitat modification and fragmentation studies, geographic location and landscape context appeared to modify dung beetle response by influencing the available pool of colonists. We discuss potential underlying mechanisms and conclude with recommendations for management and conservation and for future research.
Elizabeth Nichols - One of the best experts on this subject based on the ideXlab platform.
-
ecological functions and ecosystem services provided by scarabaeinae dung beetles
Biological Conservation, 2008Co-Authors: Elizabeth Nichols, Trond Larsen, Sacha Spector, Julio Louzada, Sandra Amezquita, Mario FavilaAbstract:Clear understanding of the links between ecological functions and biodiversity is needed to assess and predict the true environmental consequences of human activities. Several key ecosystem functions are provided by coprophagous beetles in the subfamily Scarabaeinae (Coleoptera: Scarabaeidae), which feed on animal excreta as both adults and larvae. Through manipulating feces during the feeding process, dung beetles instigate a series of ecosystem functions ranging from secondary seed dispersal to nutrient cycling and parasite suppression. Many of these ecological functions provide valuable ecosystem services such as biological pest control and soil fertilization. Here we summarize the contributions of dung beetles to nutrient cycling, bioturbation, plant growth enhancement, secondary seed dispersal and parasite control, as well as highlight their more limited role in pollination and trophic regulation. We discuss where these ecosystem functions clearly translate into ecosystem services, outline areas in critical need of additional research and describe a research agenda to fill those gaps. Due to the high sensitivity of dung beetles to habitat modification and changing dung resources, many of these ecological processes have already been disrupted or may be affected in the future. Prediction of the functional consequences of dung beetle decline demands functional studies conducted with naturally assembled beetle communities, which broaden the geographic scope of existing work, assess the spatio-temporal distribution of multiple functions, and link these ecosystem processes more clearly to ecosystem services.
-
global dung beetle response to tropical forest modification and fragmentation a quantitative literature review and meta analysis
Biological Conservation, 2007Co-Authors: Elizabeth Nichols, Trond Larsen, Sacha Spector, Adrian L V Davis, Federico Escobar, Mario Favila, Kevina VulinecAbstract:Although insects are crucial for maintaining ecosystem function, our understanding of their overall response to human activity remains limited. This is no less true of dung-burying beetles (Coleoptera: Scarabaeidae: Scarabaeinae), which provide a suite of critical ecosystem functions and services, yet but face multiple conservation threats, particularly from landscape conversion. Here we use a review and meta-analysis to synthesize the current knowledge concerning response to tropical forest modification and fragmentation of dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae). For every modified habitat type and individual forest fragment across 33 studies, we calculated six dung beetle community parameters, standardized relative to intact tropical forest. We organized modified habitats along an approximate disturbance gradient ranging from selectively logged, late and early secondary forest, through agroforestry, tree plantations, to annual crops, cattle pastures and clear-cuts. Secondary forests, selectively logged forest and agroforests supported rich communities with many intact forest species, while cattle pastures and clear-cuts contained fewer species overall with few forest-dwelling species. Abundance generally declined with increasing modification, but was quite variable. Communities in open habitats were often characterized by hyper-abundance of a small number of small-bodied species, leading to low evenness. Across fragmentation studies, dung beetle species richness, abundance and evenness declined in smaller forest fragments. Richness and abundance sometimes declined in more isolated fragments, although this response appeared to depend on matrix quality. Across both habitat modification and fragmentation studies, geographic location and landscape context appeared to modify dung beetle response by influencing the available pool of colonists. We discuss potential underlying mechanisms and conclude with recommendations for management and conservation and for future research.
