91 research outputs found
Species boundaries of Pardosa concinna and P. lapponica (Araneae: Lycosidae) in the northern Nearctic: morphology and DNA barcodes
No full textSim, Kathrin A., Buddle, Christopher M., Wheeler, Terry A. (2014): Species boundaries of Pardosa concinna and P. lapponica (Araneae: Lycosidae) in the northern Nearctic: morphology and DNA barcodes. Zootaxa 3884 (2): 169-178, DOI: http://dx.doi.org/10.11646/zootaxa.3884.2.
FIGURE 2 in Species boundaries of Pardosa concinna and P. lapponica (Araneae: Lycosidae) in the northern Nearctic: morphology and DNA barcodes
No full textFIGURE 2. Box plots (heavy line = median; box = quartiles; dashed line = range) of genitalic characters of Nearctic Pardosa lapponica and P. concinna. The mean size of all characters is significantly larger in P. concinna (grey boxes), but the size range overlaps between the two species. l.—length; M.—median; w.—width.Published as part of Sim, Kathrin A., Buddle, Christopher M. & Wheeler, Terry A., 2014, Species boundaries of Pardosa concinna and P. lapponica (Araneae: Lycosidae) in the northern Nearctic: morphology and DNA barcodes, pp. 169-178 in Zootaxa 3884 (2) on page 173, DOI: 10.11646/zootaxa.3884.2.5, http://zenodo.org/record/495160
FIGURE 2 in Species boundaries of Pardosa concinna and P. lapponica (Araneae: Lycosidae) in the northern Nearctic: morphology and DNA barcodes
No full textFIGURE 2. Box plots (heavy line = median; box = quartiles; dashed line = range) of genitalic characters of Nearctic Pardosa lapponica and P. concinna. The mean size of all characters is significantly larger in P. concinna (grey boxes), but the size range overlaps between the two species. l.—length; M.—median; w.—width.Published as part of Sim, Kathrin A., Buddle, Christopher M. & Wheeler, Terry A., 2014, Species boundaries of Pardosa concinna and P. lapponica (Araneae: Lycosidae) in the northern Nearctic: morphology and DNA barcodes, pp. 169-178 in Zootaxa 3884 (2) on page 173, DOI: 10.11646/zootaxa.3884.2.5, http://zenodo.org/record/495160
FIGURE 3 in Species boundaries of Pardosa concinna and P. lapponica (Araneae: Lycosidae) in the northern Nearctic: morphology and DNA barcodes
No full textFIGURE 3. Variation within the epigynes of female Pardosa lapponica and P. concinna specimens: a) P. lapponica specimen from Dempster Hwy, hood low and short septal ridge; b) P. lapponica from Dempster Hwy, hood low and septal pocket irregular; c) P. lapponica from Churchill, hood malformed and septal ridge completely exposed; d) P. concinna from North Battleford, hood high and septal pocket smooth; e) P. concinna from Yellowknife, hood malformed with exposed septal ridge; and f) P. lapponica from Churchill, straight and curved spermathecae. White arrows indicate the hood. The black arrows indicate the septal pockets. The dashed arrows indicate the copulatory tubes, curved in d) and straight in e).Published as part of Sim, Kathrin A., Buddle, Christopher M. & Wheeler, Terry A., 2014, Species boundaries of Pardosa concinna and P. lapponica (Araneae: Lycosidae) in the northern Nearctic: morphology and DNA barcodes, pp. 169-178 in Zootaxa 3884 (2) on page 174, DOI: 10.11646/zootaxa.3884.2.5, http://zenodo.org/record/495160
FIGURE 4 in Species boundaries of Pardosa concinna and P. lapponica (Araneae: Lycosidae) in the northern Nearctic: morphology and DNA barcodes
No full textFIGURE 4. Apical division of the male pedipalp: a) Pardosa concinna from Yellowknife; b) P. concinna from Yellowknife; and c) P. lapponica from Dempster Hwy. The white arrow indicates the position of the protrusion on the palea, present in a) and absent in b) and c). Black arrows indicate the conductor, protruding past the lower limit of the terminal apophysis in c). The conserved shape of the embolus can be seen in b) and c). Inter-specific variation in the terminal apophysis can be seen between a), b) and c).Published as part of Sim, Kathrin A., Buddle, Christopher M. & Wheeler, Terry A., 2014, Species boundaries of Pardosa concinna and P. lapponica (Araneae: Lycosidae) in the northern Nearctic: morphology and DNA barcodes, pp. 169-178 in Zootaxa 3884 (2) on page 174, DOI: 10.11646/zootaxa.3884.2.5, http://zenodo.org/record/495160
The effects of harvesting and decaying logs on oribatid (acari: oribatida) mite assemblages in eastern Canadian mixedwood boreal forest
No full textEcosystem-based management (e.g. partial cut harvesting) retains some components of natural forest structure such as downed woody material (DWM) and may have less impact than clear cutting on forest floor fauna. I tested how partial cut harvesting affects oribatid mite assemblages and explored the spatial influence of decomposing logs on oribatids on the forest floor at the sylviculture et aménagement forestiers écosystémique (SAFE) research station in Abitibi, Québec. The importance of determining the extraction duration of the specific apparatus used in biodiversity studies was also demonstrated. In June 2006, litter and soil were sampled in mixedwood boreal forest where the following treatments were replicated three times: clear cut harvest, 1/3 partial cut harvest, 2/3 partial cut harvest, controlled burn (after harvest) and uncut control. As well, six decayed logs were sampled at three distances each: directly on top of the log (ON), directly beside the log (ADJ) and at least one metre away from the log and any other fallen wood (AWAY). Samples ON logs consisted of a litter layer sample, an upper wood sample and an inner wood sample. Samples at the ADJ and AWAY distances consisted of litter samples and soil cores. Eight years after harvest, clear cutting appears to have had a homogenizing effect on oribatid species composition, and partial cuts had more similar species composition to the uncut control within their respective blocks. In litter, diversity decreased with increasing harvesting intensity but in soil it increased. In the burn, species richness was significantly different from the other treatments, and there was some change in species-specific abundance. The highest species richness was collected ON logs, and logs harboured a distinct oribatid species composition compared to the forest floor. There were species-specific changes in relative abundance with increasing distance away from DWM, and each layer (litter, wood and soil) exhibited a uniquL'aménagement écosystémique (e.g. coupe partielle) permet de conserver certains éléments structuraux tel les débris ligneux grossiers et pourrait avoir pour effet de minimiser l'impact de la récolte sur la pédofaune. J'ai évalué l'effet de la coupe partielle et l'influence spatiale du bois mort au sol sur les assemblages d'oribates (Acarina) dans le dispositif expérimental SAFE (sylviculture et aménagement forestier écosystémique) en Abitibi, Québec. L'importance de déterminer la période d'extraction appropriée selon l'équipement utilisé a aussi été démontrée. Des échantillons de sol et de litière ont été récoltés en juin 2006 en forêt boréale mixte où les traitements suivants ont été répliqués trois fois: coupe totale, rétention de 33% des tiges, rétention de 66% des tiges, brûlage dirigé après coupe et peuplement témoin. Aussi, des échantillons ont été prélevés à trois distances de six troncs en décomposition: sur le tronc (ON), immédiatement à côté (ADJ) et à une distance minimale de 1 m de tout débris ligneux (AWAY). Les échantillons ON étaient formés d'un échantillon de litière, d'un échantillon de bois superficiel et d'un échantillon de bois d'intérieur. Les échantillons ADJ et AWAY étaient formés d'échantillons de litière et de sol. Huit ans après la récolte, la coupe totale semble avoir homogénéisé la composition spécifique des assemblages d'oribates, alors que celles trouvées dans les traitements de coupe partielle restent plus semblables aux témoins. Dans la litière, la diversité diminue avec une plus haute intensité de récolte alors que l'inverse est vrai pour le sol. Suite au brûlage dirigé, la richesse spécifique est différente des autres traitements, et certains changements ont été observés au niveau de l'abondance de certaines espèces. La plus haute richesse spécifique a été observée dans les échantillons ON, et ces troncs abritaient un composition spéci
Community structure of an assemblage of Northern flies (Diptera) among varying spatial scales
No full textThis thesis explores the ecological and evolutionary dynamics shaping northern Canadian Diptera assemblages. Despite their significance in Arctic ecosystems, research on northern flies is limited due to taxonomic challenges. Molecular tools, such as the cytochrome c oxidase subunit I (COI) universal animal barcode fragment and Barcode Index Numbers (BINs), provide a solution for studying fly community structure. Real Diptera BIN datasets were used in this thesis to explore fly community assembly. Understanding why groups of species are found at one location but not another requires consideration of their physiological requirements/limitations, dynamics with other species and abiotic environment, and evolutionary history. These processes act as successive sieves at the regional and local scale: evolutionary and biogeographic processes create the species pool; dispersal and physiological tolerances decide species presence; biotic and abiotic interactions operate at individual and species levels. Two popular metrics used to measure “community assembly” are the standard effect size of mean nearest taxon distance (ses.MNTD) and mean pairwise distance (ses.MPD), which compare local samples to the regional species pool. The first study assesses the reliability of calculating ses.MNTD and ses.MPD while subsampling a Diptera dataset from Churchill, Manitoba. Results suggest high sample percentages are necessary for accurate calculations, with optimal subsampling strategies depending on goals. The second study had a continental focus and investigates muscid fly ecology and phylogenetic structure across ecoclimatic zones in the Canadian North using 15,675 Muscidae individuals across 207 BINs. Unique patterns in assemblage composition and evolutionary structure were revealed, highlighting the influence of environmental factors on regional species pools. The third study had a local focus and examined the ecological and evolutionary dynamics of brachyceran Diptera in Churchill, Manitoba. 1,066 Brachycera individuals were collected, and 910 were successfully barcoded and grouped into 146 BINs. Distinct assemblages were found in boreal forest and tundra habitats and larger species were favored in the tundra, suggesting habitat-specific trait selection. Overall, this thesis highlights the complex interplay between ecological and evolutionary processes in shaping fly assemblages in the Canadian North, which is crucial knowledge for informing conservation and ecosystem management strategies in the face of climate change
Natural enemy ecology in apple orchards: spider colonization of orchards and effects of kaolin on the apple pest «Choristoneura rosaceana» and its natural enemies
No full textIntegrated pest management (IPM) uses multiple approaches to keep pest levels below economic injury levels. Integrated pest management combines preventative methods such as biocontrol with curative methods; this synthesis requires an understanding of the ecology of natural enemies in the agroecosystem. Arthropod natural enemy communities in apple orchards are diverse, and spiders (Araneae) are particularly abundant and species rich. Orchard arthropods are affected by multiple factors, both external (e.g. immigration) and internal (e.g. pesticides) to the orchard environment. In this thesis I explored the influence of these factors on natural enemy communities in apple orchards. I investigated which natural habitats adjacent to orchards are potential sources of spiders, and the influence of distance from a source habitat on the composition of colonizing spider assemblages. I tested how kaolin clay, a pest management technique, affects orchard generalist predator communities and the parasitoids of a pest species and prey item of spiders, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae). I also examined how applications of kaolin to apple foliage affect the behaviour of C. rosaceana larvae and whether this alters the predation on larvae by spiders. Comparisons of spider assemblages in natural habitats adjacent to apple orchards in southern Québec indicated that deciduous forest had spider assemblages similar in to those in the orchard foliage. The composition of the spiders that colonized the apple orchards changed over a small spatial scale (10-50 m). The relative abundance of individuals among spider species in older orchards was more evenly distributed than in assemblages of recently colonized spiders, suggesting that local dynamics also shape the composition of the spider assemblages over time. Kaolin on apple leaves changed C. rosaceana larval behaviour: third and fourth instar larvae and neonates took longer to build leaf shelters, and neLa lutte intégrée combine plusieurs méthodes de lutte pour maintenir les populations de ravageurs sous des seuils d'intervention. Ces méthodes incluent des mesures préventives, comme l'augmention des agents de lutte biologique, et des mesures curatives. Cette synthèse nécessite des connaissances sur l'écologie des vergers et ses espèces. Les communautés d'espèces utiles dans les vergers sont diverses, et les assemblages d'araignées (Araneae) sont notamment abondants et riches en espèces. Plusieurs facteurs affectent les organismes dans les vergers, incluant les facteurs externes (ex. immigration) et internes (ex. l'application d'insecticides). Dans cette thèse, j'ai étudié l'influence de ces facteurs sur les communautés d'araignées et d'autres espèces utiles. J'ai déterminé quels habitats adjacents au verger ont le potentiel d'être des sources d'araignées, et comment la distance de la source change les dynamiques de colonisation des vergers par les araignées. J'ai déterminé les effets du kaolin (un pesticide à base d'argile) sur les assemblages de prédateurs arthropodes et parasites du ravageur Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae) dans les vergers. Les forêts adjacentes au verger ont des assemblages d'araignées similaires à ceux des vergers, vraisemblablement parce que leur structure végétale et leur niveau de dérangement temporel sont semblables. La composition des assemblages d'araignées change à petite échelle spatiale (10-50 m). La répartition des individus parmi les espèces des assemblages d'araignées dans les vergers établis était plus homogène que celle des vergers récemment colonisés. Ceci suggère que les dynamiques locales façonnent aussi la composition des assemblages d'araignées. Le kaolin a changé le comportement des larves de C. rosaceana: les larves ont requis plus de temps pour se faire un abri sur les tiges traitées avec le kaolin. Les larves néonates se sont disp
Ecology of beetle assemblages in a Panamanian tropical forest with taxonomic notes on Curculionidae and Histeridae
No full textBeetles (Insecta, Coleoptera) contribute the most to global species richness of multicellular organisms with approximately one-fourth of all described species, the highest proportion of which can be found in tropical regions where many remain to be discovered and described. However, biodiversity in tropical regions is threatened by land use change and conversion of forests for agriculture, pasture and other uses. In this thesis I focus on tropical beetles as their ecological diversity, high richness and abundance, makes them suitable for a variety of studies that can add to our understanding of biodiversity and practical applications in management and conservation. The study was carried out in a natural moist tropical forest in the San Lorenzo Protected Area, next to the community of Achiote, Colón Province, Republic of Panama. Thirty flight intercept traps were placed in six transects at five distances from the forest edge (0, 10, 50, 100, 250 m) to sample beetles at six periods between May 2007 and May 2008. Over 40,000 beetles were collected and identified to the level of family, and two families were selected and further identified to species level (Curculionidae, 2079 individuals from 355 species; Histeridae, 3022 individuals from 112 species).I investigated the influence of distance and adjacent habitat (low or high contrasting habitat) on beetle assemblages along six transects from the edge towards the interior of the forest. I found that the relative abundance of beetles decreased at the edges in comparison to the interior of the forest. The sites adjacent to low contrasting habitats (i.e. coffee plantations) had a higher relative abundance of beetles than sites adjacent to high contrasting habitats (i.e. pastures). The β-diversity of beetle assemblages was found to differ significantly among sites adjacent to either coffee plantations or pastures and at the edges of the forest. The β-diversity within edges was higher for sites adjacent to pastures than those adjacent to coffee plantations. This study highlights the influence of the adjacent habitat with low contrast to the forest in diminishing the harsh effects of edges on biodiversity.I further investigated the seasonal influence of precipitation on beetle assemblages collected between May 2007 and May 2008. The highest relative abundance and species richness of beetles were found early in the wet season. I also found a high turnover (β-diversity) between the early wet and the late wet seasons. I detected, using PerMANOVA, that the turnover of beetle assemblages was correlated significantly with the amount of precipitation. I conclude that the high β-diversity throughout the seasons might be related to different resources available and different assemblages of beetles exploiting those resources. In this thesis, I also provide the first dichotomous key to the subfamilies Curculionidae known from Central America based on the latest classification of the family. This work presents a synthesis of information about each subfamily. In the last chapter three new species belonging to the tribe Nymphistrini of the obligate myrmeco- and termitophilous subfamily Haeteriinae (Coleoptera: Histeridae) are described from Central America: Nymphister rettenmeyeri (Costa Rica and Panama), Trichoreninus carltoni (Belize and Honduras) and T. neo (Costa Rica and Panama).Les coléoptères (Insecta, Coleoptera) contribuent à la majorité de la richesse globale d'espèce d'organismes multicellulaires, ce qui approxime un quart de toutes les espèces décrites. La plus grande proportion des coléoptères provenant des régions tropicales, où plusieurs restent encore à être découvertes et décrites. Toutefois, la biodiversité des régions tropicales est menacée par le changement d'utilisation des terres et la conversion des forêts pour l'agriculture, les pâturages et autres usages. Dans cette thèse, je me concentre sur les coléoptères tropicaux puisque leur diversité écologique, leur haute richesse en espèce et abondance en fond un groupe de choix pour une variété d'études qui peuvent ajouter à notre compréhension de la biodiversité et aider au développement d'applications pratiques pour la gestion et la conservation. L'étude a été conduite dans une forêt tropicale humide naturelle de la Zone Protégée San Lorenzo, à proximité de la communauté Achiote, Province de Colón, République de Panama. Trente trappes d'interception ont été placées dans six transects à cinq différentes distances de la bordure de la forêt (0, 10, 50, 100, 250 m) pour échantillonner les coléoptères à six reprises entre mai 2007 et 2008. Plus de 40,000 coléoptères ont été collectés et identifiés à la famille et deux familles ont été sélectionnées pour identifier jusqu'à au niveau de l'espèce (Curculionidae: 2079 individus représentant 355 espèces; Histeridae: 3022 individus représentant 112 espèces). J'ai investigué l'influence de la distance et de l'habitat adjacent (contraste d'habitat faible ou élevé) sur la composition des coléoptères à travers six transects à partir de la bordure de la forêt jusqu'à la forêt intérieure. J'ai trouvé que l'abondance relative des coléoptères diminue près de la bordure en comparaison à la forêt intérieure. Les sites adjacents aux habitats faiblement contrastant (i.e. plantation de café) avaient une abondance relative plus élevé de coléoptères que les sites adjacents aux habitats à contraste élevé (i.e. pâturages). La β-diversité de l'assemblage des coléoptères a été trouvée significativement différente parmi les sites adjacents à soit les plantations de café ou les pâturages et à la bordure de la forêt. La β-diversité dans les bordures était plus élevé pour les sites adjacents aux pâturages que ceux adjacents aux plantations de café. Cette étude souligne l'influence d'un habitat adjacent à faible contraste par rapport à la forêt tend à diminuer l'effet négatif de la bordure sur la biodiversité. J'ai investigué plus en profondeur l'influence saisonnier des précipitations sur la composition des coléoptères collectés entre mai 2007 et mai 2008. L'abondance et la richesse les plus élevées pour les coléoptères ont été obtenues dans le début de la saison humide. J'ai aussi trouvé une β-diversité élevée (rotation d'espèces) entre le début et la fin de la saison humide. J'ai remarqué que le renouvellement de la composition des coléoptères était significativement corrélée avec la quantité de précipitation en utilisant le test PerMANOVA. Je conclue que la β-diversité élevée à travers les saisons peut être reliée à la différence des ressources disponibles et aux différents assemblages de coléoptères exploitant ces ressources. Dans cette thèse, je fournis aussi la première clé dichotomique pour les sous-familles des Curculionidae connues pour l'Amérique Centrale, basée sur la plus récente classification de la famille. Ce travail présente une synthèse de l'information pour chacune de ces sous-familles. Dans le dernier chapitre, trois nouvelles espèces appartenant à la tribu Nymphistrini, les myrmeco- et termitophile obligatoire de la sous-famille Haeteriinae (Coleoptera: Histeridae), sont décrites pour l'Amérique Centrale: Nymphister rettenmeyeri (Costa Rica et Panama), Trichoreninus carltoni (Belize et Honduras) et T. neo (Costa Rica et Panama)
Life history and distribution of the Arctic pseudoscorpion, Wyochernes asiaticus (Chernetidae)
No full textThe Pseudoscorpiones are a remarkable yet understudied order of arachnids. The northernmost species in North America, Wyochernes asiaticus (family Chernetidae), occurs under rocks beside rivers or creeks and can be found above the Arctic Circle in Canada. In North America, the species is limited to the northwest, although its global distribution includes parts of Asia. It is presumably a Beringian species with quite specialized habitat affinities. I report on some life history traits of this species, based on examination of nearly 600 specimens from 16 localities in the Yukon and Northwest Territories. All life stages were collected. Of the females, 17% were carrying brood sacs, with an average of 10.5 eggs per brood sac; larger females tended to have larger clutch sizes. Despite these data on the natural history and distribution of W. asiaticus, its phylogeographic history and how the species feeds, disperses, and recolonizes habitats after flooding remain largely unknown
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