Identification and characterization of 21 polymorphic microsatellite loci from the mycophagous fly Drosophila neotestacea

Drosophila neotestacea is a mushroom‐feeding fly that is common in the temperate and boreal forests of North America. Here I describe the isolation and characterization of 21 polymorphic microsatellite loci from the D. neotestacea genome. In a sample of flies from Rochester, New York, the expected and observed heterozygosities ranged from 0.344 to 1.000 and from 0.384 to 0.923, respectively. Of the 21 markers, six were likely X‐linked, seven showed a departure from Hardy–Weinberg equilibrium, and none were found to be in linkage disequilibrium. These loci will facilitate future ecological and population genetic studies of D. neotestacea.     

Multi‐scale ant diversity in savanna woodlands: an intercontinental comparison

Ecological patterns and processes are highly scale‐dependent, but few studies have used standardized methodology to examine how scale dependency varies across continents. This paper examines scale dependency in comparative ant species richness and turnover in savannas of Australia and Brazil, which are well‐matched climatically but whose ant faunas have contrasting biogeographic origins. The study was conducted in savanna woodland near Darwin in northern Australia and Uberlândia in central Brazil. The sampling design consisted of eight 400‐m line transects, four in each continent, with eight pitfall traps located on and around each of 20 trees evenly spaced along each transect. Ant richness and species turnover were compared at three spatial scales: pitfalls associated with a tree, trees within a transect and transects within a savanna. The composition of the Australian and Brazilian savanna ant faunas was broadly similar at the subfamily level, despite the very low proportion of shared genera and species. The ground and arboreal ant faunas were very distinct from each other in both savannas, but especially in Brazil. Overall ant abundance was almost three times higher in Australia than in Brazil, both on the ground and on vegetation, but overall species richness was higher in Brazil (150 species) than in Australia (93). There was no significant difference in the mean number of species per pitfall trap, but the mean species richness was significantly higher in Brazil than in Australia at both the tree and transect scales. We attribute these scale‐dependent intercontinental differences to biogeographical and historical factors in Brazil that have led to a large regional pool of arboreal species of rainforest origin. Our study underlines the importance of biogeographical context when conducting comparative analyses of community structure across biogeographical scales, and highlights the importance of process acting at regional scales in determining species richness in ant communities.     

Ancient Middle Niger: Urbanism and the Self-Organizing Landscape

Ancient Middle Niger: Urbanism and the Self-Organizing Landscape . Roderick J. McIntosh. New York: Cambridge University Press, 2005. 261 pp.     

Polymorphic microsatellite loci in Mimulus guttatus and related species

The evolution of self-fertilization from outcrossing is one of the most common evolutionary transitions in flowering plants. One goal of our research is to develop a linkage map based upon microsatellite loci in Mimulus guttatus and the selfing derivative M. nasutus in order to examine the genetics of one such transition. Here we present 19 primer pairs that detect polymorphisms between these two species. Within-population allelic surveys demonstrate the value of these markers for detailed analysis of population structure. We have found also that many of the microsatellites are conserved in more distantly related Mimulus species, and may thus serve as useful genetic markers for population genetic and comparative mapping studies within this diverse genus.     

Systematics and biogeography of the genus Actenodia (Coleoptera: Meloidae: Mylabrini)

Abstract.  The genus Actenodia Laporte de Castelnau (Meloidae: Mylabrini) is revised. It includes 18 species distributed in the Mediterranean and Saharo-Arabian regions, and in eastern and southern Africa; A. carpanetoi sp.n. from Mozambique is described. The bionomics of the genus is summarized, according to a collection of records on phenology, elevation, habitat preference and host plants. A classification of the genus is proposed after a morphological cladistic analysis: one Afrotropical lineage clearly emerged with three distinct groups of species, whereas other taxa, all Palaearctic except A. mirabilis , remained unresolved. The analysis of the nuclear internal transcribed spacer 2 rDNA sequences of some Palaearctic and Afrotropical species supports the distinction of the Afrotropical lineage. The first instar larvae of two species, A. chrysomelina from southern Africa and A. denticulata from Arabia, are described for the first time and compared with two other Palaearctic species described previously; inferences from larval morphology are discussed. The adult morphology of all species is described briefly and illustrated, and a key to the species is provided, as well as locality data. Three new synonymies are proposed: A. extera Dvořák, 1993 syn.n. = A. septempunctata Baudi di Selve, 1878; A. sexpunctata Pic, 1948 syn.n . = A. curtula Fähraeus, 1870 ; A. unimaculata lanzai Kaszab, 1973 syn.n . = A. unimaculata Pic, 1908. The biogeography of the genus is discussed within the framework of a more general analysis of the disjunct distribution models.     

Preference and performance of generalist and specialist herbivores on chemically defended host plants

1. Both the physiological efficiency (PE) hypothesis and the preference–performance (PP) hypothesis address the complex interactions between herbivores and host plants, albeit from different perspectives. The PE hypothesis contends that specialists are better physiologically adapted to their host plants than generalists. The PP hypothesis predicts that larvae perform best on the host plant preferred by ovipositing females. 2. This study tests components of both hypotheses using the specialist checkerspot, Euphydryas anicia, the generalist salt marsh caterpillar, Estigmene acrea, and host plants in the genus Penstemon, which are defended by iridoid glycosides. 3. In laboratory experiments, the generalist preferred and performed significantly better on the less well defended host plant species. This is consistent with results from a common garden experiment where the less well defended Penstemon species received more damage from the local community of generalists. Larvae of the specialist checkerspot preferred the more chemically defended species in the laboratory, but performed equally well on both hosts. However, field experiments demonstrated that adult checkerspot females preferred to oviposit on the less well defended host plant. 4. Components of the physiological efficiency hypothesis were supported in this system, as the specialist outperformed the generalist on the more iridoid glycoside‐rich host plant species. There was no support for the PP hypothesis, however, as there was no clear relationship between female preference in the field and offspring performance in the laboratory.     

Characterization of eight microsatellite loci in Steller sea lions (Eumetopias jubatus)

Steller sea lions (Eumetopias jubatus) are listed as an endangered species in western Alaska and have exhibited a significant population decline throughout their range. Eight microsatellite loci were isolated from genomic DNA libraries. In addition, all these markers were found to be variable in nine individuals of the California sea lion (Zalophus californicus). This panel of markers was developed to analyse population structure in Steller sea lions throughout their range.     

The nutrient budget of a small eutrophic loch and the effectiveness of straw bales in controlling algal blooms

1. A 1-year intensive study of nutrient flows in Airthrey Loch, central Scotland, a small eutrophic [mean total phosphorus (TP) = 61.1 μg P l^–1] well-flushed freshwater body (area, 6.9 ha; mean depth, 1.85 m; volume, 1.274 × 10⁵ m³; retention time, 0.44 yr), was undertaken.
2. The nutrient budget was dominated by large allochthonous P inputs, equivalent to an areal load to the loch of 8.56 kg P ha^–1 yr^–1, which occurred predominantly during winter. In the summer, when TP inputs were low, water column levels of TP still increased, as a result of aerobic P release from sediments.
3. Sorption experiments indicated potential for sediment P release at water P concentrations of up to 200 μg P l^–1.
4. Aerobic release rate of P from sediments to the water column of Airthrey Loch was estimated to be of the order of 1 mg P m^–2 day^–1, and occurred during periods of elevated water column pH.
5. Straw bales placed in the loch to retard algal blooms were found not to have any demonstrable impact on algal concentrations observed during the study.     

A molecular phylogenetic study of Cucujidae s.l. (Coleoptera: Cucujoidea)

Of all the superfamilies within the megadiverse order Coleoptera (Insecta), Cucujoidea (Cucujiformia) is arguably the most problematic taxonomically. The families comprising Cucujidae s.l. (Silvanidae, Laemophloeidae, Passandridae and Cucujidae s.s. represent a large portion of cucujoid diversity. Herein we present the results of a rigorous molecular phylogenetic analysis of Cucujidae s.l. using maximum‐likelihood and Bayesian analyses of seven genes. Representatives of over half of the families of Cucujoidea (excluding the cerylonid series), as well as a broad sampling of Silvanidae and Laemophloeidae, were analysed. The monophyly of Cucujidae s.l. is rejected but a subgrouping of taxa that may form the core of a natural cucujoid lineage is recovered. This clade consists of two large monophyletic groups including several families each. Relationships among these smaller cucujoid groups are discussed, including several novel phylogenetic hypotheses, whereas morphological characters considered significant for classification in Cucujidae s.l. are evaluated in light of these phylogenetic hypotheses. Silvaninae, Telephanini, Brontini and Brontinae are recovered as monophyletic in the Bayesian analysis, but the former two are recovered as paraphyletic in the maximum‐likelihood analysis. Our results support the placement of Psammoecus Latreille within Telephanini and also recover a paraphyletic Telephanus Erichson. Silvaninae is divided into three lineages, each representing a potential tribal lineage. Laemophloeidae is rendered paraphyletic in all analyses by Propalticidae and the latter is herein formally transferred to Laemophloeidae stat.n . Several suprageneric laemophloeid clades are recovered and discussed as potential higher‐level groups. Laemophloeus Dejean is not recovered as monophyletic.     

What limits a rare alpine plant species? Comparative demography of three endemic species of Myosotis (Boraginaceae)

Abstract Establishing what are the underlying causes of species range limits is of fundamental interest in ecology. We followed the fate of individually mapped plants of three endemic New Zealand high‐alpine species of Myosotis, over a period of 9 years. The species provide contrasts in their geographical range and their demography. Myosotis oreophila Petrie is rare and extremely localized (c. 0.5 ha extent), Myosotis cheesemanii Petrie is regionally endemic, and Myosotis pulvinaris Hook. f. is more widespread. All three occur on the Dunstan Mountains, Central Otago, South Island, New Zealand within a 1‐km radius, and individual plants were followed in four permanent plots. The three species differed in their longevity and in population variability, with the most widespread species (M. pulvinaris) having the lowest survival (61% per year), the fewest old plants (only 3% of plants present in 1993 surviving until 2001), no increase in survival rates with age, and the most variability in total numbers across years. Both of the rare species, M. oreophila and M. cheesemanii, had higher survival (75% and 88%, respectively, per year) especially for older plants, many older plants (20% and 59%, respectively, of 1993 plants surviving until 2001), and lower variability in total numbers across years. These results are consistent with other studies showing that rare plant species tend to have higher inertia than more common congeners. The range limits of M. oreophila showed a high level of spatial constancy on a scale of metres over the 9 years, despite 80% turnover in plants during that time. The M. oreophila population showed lower mean densities of plants near to the population boundaries, identical age‐specific survival rates, but lower flowering probabilities, than the core of the population. We were unable to detect any abiotic differences between inside and outside the M. oreophila range in terms of topography, soil parent materials, microclimate or through manipulation of snow cover. Disturbance may be a factor affecting the distribution of M. cheesemanii but limiting factors for M. oreophila and M. pulvinaris are likely to be biotic (competition, seed limitation, dispersal capacity) and/or historic. Further experimentation is recommended.