Differential application of lambda-cyhalothrin to control the sandfly Lutzomyia longipalpis

Abstract. To study the impact of residual pyrethroid insecticide on the abundance and distribution of peridomestic Lutzomyia longipalpis , the sandfly vector of visceral leishmaniasis in Brazil, lambda-cyhalothrin was applied at 20 mg a.i.m^-2 in the following interventions: (i) spraying of all animal pens in a village (blanket coverage); (ii) treatment of a subset of animal pens, either by spraying, or by installation of insecticide-impregnated 1 m² cotton sheets as 'targets' (focal coverage).
By sampling with CDC light traps, and using a novel analytical approach, we detected a 90% reduction in Lu. longipalpis abundance in sprayed sheds of the focal intervention. However, there was no discernible effect on the abundance of other phlebotomines trapped in sheds, or on the abundance of Lu. longipalpis in untreated dining-huts and houses. This differential impact on Ludongipalpis abundance is explained in terms of the disruption of male pheromone production. Treated targets were approximately half as effective as residual spraying in reducing the abundance of Lu.longipalpis in sheds.
Following blanket intervention, the abundance of Lu.longipalpis in traps fell by only 45% (not significant): catches at untreated dining-huts actually increased, possibly because the blanket coverage diverted Lu. longipalpis away from major aggregation sites at animal pens. It is recommended that care be taken during vector control programmes to ensure that all potential aggregation sites are treated. The possible consequences of leaving some sites untreated include poor control of peridomestic sandfly abundance and an increase in the biting rate on dogs and humans.     

Biogeography of Great Basin butterflies: revisiting patterns, paradigms, and climate change scenarios

We used comprehensive data on butterfly distributions from six mountain ranges in the Great Basin to explore three connected biogeographic issues. First, we examined species richness and occurrence patterns both within and among mountain ranges. Only one range had a significant relationship between species richness and area. Relationships between species richness and elevation varied among mountain ranges. Species richness decreased as elevation increased in one range, increased as elevation increased in three ranges, and was not correlated in two ranges. In each range, distributional patterns were nested, but less vagile species did not always exhibit greater nestedness. Second, we compared our work with similar studies of montane mammals. Results from both taxonomic groups suggest that it may be appropriate to modify existing general paradigms of the biogeography of montane faunas in the Great Basin. Third, we revisited and refined previous predictions of how butterfly assemblages in the Great Basin may respond to climate change. The effects of climate change on species richness of montane butterflies may vary considerably among mountain ranges. In several ranges, few if any species apparently would be lost. Neither local species composition nor the potential order of species extirpations appears to be generalizable among ranges.     

Towards a monophyletic genus Albinaria (Gastropoda, Pulmonata): the first molecular study into the phylogenetic position of eastern Albinaria species

Recent molecular phylogenetic studies of the terrestrial snail genus Albinaria have caused a radical reassessment of its taxonomy. These studies, however, were limited to western species. This paper examines mitochondrial 12S sequences and nuclear ITS1 & 2 sequences of both eastern and western species, and demonstrates that Albinaria, in its most recent definition, is not monophyletic. Both molecular datasets place ' Albinaria ' hedenborgi from Lebanon in a well-supported clade with species of the genus Cristataria , distributed south-east of the vicariant range of Albinaria . The remaining species from Cyprus, Turkey and Greece constitute a well-supported monophyletic group. These two clades form geographical clusters, whereas Albinaria in the current definition (including ' A. '  hedenborgi ) has a disjunct distribution. ' A.' hedenborgi should therefore be classified with Cristataria , together with the morphologically similar and geographically close ' A. '  nadimi .  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 531−542.     

Analysis of the Antigenic Relationships Among Trichomonas,Histomonas, Dientamoeba and Entamoeba III. Immunoelectrophoresis Technics*

Antigens prepared from Trichomonas gallinae, Histomonas meleagridis, Dientamoeba fragilis, Entamoeba invodens and Entamoeba histolytica were separated by electrophoresis in agar gels and reacted with antisera prepared in rabbits against each of the 5 species. The most numerous and strongest precipitin lines were obtained from reactions between the homologous antigens and antisera. Direct and cross-absorption reaction methods were employed with each antiserum and the various antigens to ascertain quantitatively the immunologic relationships among the several organisms. Trichomonas shared many common antigens with Histomonas, fewer with Dientamoeba and none with either species of Entamoeba. Histomonas was more closely related antigenically to Dientamoeba than to Trichomonas. The histomonad had only a few weakly cross-reacting antigens in common with the 2 Entamoeba species. Dientamoeba shared the most common antigens with Histomonas, fewer with Trichomonas and the fewest with Entamoeba. Somewhat stronger cross-reactivity was obtained with anti-Dientamoeba serum and E. invadens than between this immune serum and E. histolytica. The 2 species of Entamoeba shared the largest number of common antigens with each other, and to a much lesser extent both species cross reacted with Dientamoeba. Anti-Entamoeba sera had only a few weak cross-reacting precipitins with Histomonas. No antigenic relationship was found between either species of Entamoeba and Trichomonas.     

A multivariate approach to the determination of faunal structures among European butterfly species (Lepidoptera: Rhopalocera)

Multivariate analyses of 393 butterfly species over 85 geographical areas (R- and Q-data matrices) in Europe and North Africa have produced a consistent pattern of faunal structures (units and regions). Prominent features to emerge are the latitudinal zonation of geographical units and the division of the Mediterranean into western and eastern components; southwards in Europe, endemicity increases whereas faunal structures decrease in spatial dimensions. Central Europe–from the Urals to the British Isles–forms a single large faunal structure (extent unit and region). A model has been constructed to account for Pleistocene evolutionary changes and endemism in European butterflies and for the east-west taxonomic divisions in the extent faunal structure which dominates central Europe. Periodic Pleistocene climatic changes have resulted in cycles of population extinction, isolation, evolution and migration, but the nature and timing of events has depended on the environmental tolerances of species belonging to different faunal units. During Pleistocene glaciations, southern species have been relatively static and more isolated and have evolved independently. By comparison, northern species have been more mobile and have migrated over large distances. Contact and hybrid zones among cosmopolitan species in northern Europe are probably of some antiquity. They result from persistent survival and isolation of refuge populations in the west and east Mediterranean during glacial phases; dispersal from these refuges leads to their regeneration during each interglacial.     

The fungal flora of soft fruits in relation to storage and spoilage

The fungal population of freshly harvested strawberries, raspberries and blackberries was studied throughout the fruiting seasons and the relative importance of fungi responsible for spoilage of stored fruit from different harvest dates was assessed. Botrytis cinerea, Cladosporium spp., Penicillium spp., Aureobasidium pullulans and Mucor spp. were consistently present on all three fruits while Colletotrichum gloeosporioides and Didymella applanata were prevalent on raspberries only and Epicoccum purpurascens and Alternaria spp. on blackberries only. Botrytis cinerea and Mucor mucedo were the predominant spoilage organisms of all three fruits, although the relative importance of the two fungi changed as the season progressed, especially for strawberries. Rhizopus stolonifer, Cladosporium spp., Penicillium spp. and Colletotrichum gloeosporioides were only of minor importance as spoilage organisms.     

Ecological partitioning among parapatric cryptic species

Geographic range differences among species may result from differences in their physiological tolerances. In the intertidal zone, marine and terrestrial environments intersect to create a unique habitat, across which physiological tolerance strongly influences range. Traits to cope with environmental extremes are particularly important here because many species live near their physiological limits and environmental gradients can be steep. The snail Melampus bidentatus occurs in coastal salt marshes in the western Atlantic and the Gulf of Mexico. We used sequence data from one mitochondrial (COI) and two nuclear markers (histone H3 and a mitochondrial carrier protein, MCP) to identify three cryptic species within this broad‐ranging nominal species, two of which have partially overlapping geographic ranges. High genetic diversity, low population structure, and high levels of migration within these two overlapping species suggest that historical range limitations do not entirely explain their different ranges. To identify microhabitat differences between these two species, we modelled their distributions using data from both marine and terrestrial environments. Although temperature was the largest factor setting range limits, other environmental components explained features of the ranges that temperature alone could not. In particular, the interaction of precipitation and salinity likely sets physiological limits that lead to range differences between these two cryptic species. This suggests that the response to climatic change in these snails will be mediated by changes to multiple environmental factors, and not just to temperature alone.     

The roles of Neogene geology and late Pleistocene lake levels in shaping the genetic structure of the Lahontan redside shiner Richardsonius egregius (Teleostei: Cyprinidae)

Shifting drainage patterns in western North America, shaped by geological activity and changing global climates, have influenced the evolution of many aquatic taxa. We investigated the role of late Pleistocene high stands in pluvial Lake Lahontan on the genetic structure of Richardsonius egregius, a minnow endemic to the Lahontan Basin of the western Great Basin. We used the mitochondrial cytochrome b gene to generate a phylogeny and assess intraspecific genetic diversity, to estimate divergence times between clades, and to evaluate whether gene flow currently occurs. The results obtained show that R. egregius exhibits genetic divergence between eastern and western Lahontan Basin populations. Divergence time estimates show that intraspecific genetic diversification began in the Pliocene or early Pleistocene, before the pluvial lake high stands associated with the last glacial maximum. These results imply that the fluctuating water levels in pluvial Lake Lahontan had a minimal effect on shaping the genetic architecture of R. egregius. Coalescent analyses using the immigration with migration model show that contemporary gene flow between eastern and western Lahontan Basin populations does not occur. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104 , 163–176.     

You're so vein: bundle sheath physiology,phylogeny and evolution in C3 and C4 plants

Bundle sheath (BS) anatomy is found in most C4 lineages, associated with low inter‐veinal distances (IVD) and high BS:mesophyll ratio (BS:MC). The origins, function and selective advantages of the BS in C3 lineages are relevant for understanding the environmental, molecular and phylogenetic determinants of C4 evolution. Suggested functions for BS have included structural support, hydraulic isolation, storage for water, ions, and carbohydrates, and photorespiratory carbon metabolism; we propose a central role for cavitation repair, consistent with the BS as a control centre on regulating stem and leaf hydraulic continuity. An analysis of BS traits in the phylogenetic lineages giving rise to C4 grasses (the ‘PACMAD’ clade) shows an initial enhancement in BS:MC ratio in C3 lineages, although IVD is similar to the Pooideae sister group. Using a global database, a well‐developed BS in the C3 PACMAD lineages was associated with higher precipitation and temperatures in the habitat of origin on an annual basis, with the C3 to C4 progression defined by the aridity index (AI). Maintaining leaf hydraulic conductance and cavitation repair are consistent with increased evaporative demand and more seasonal precipitation as drivers, first for the C3 BS, and then C4 diversification, under declining CO₂ concentrations in the Palaeogene and Neogene.