Molecular phylogeny of Sericostomatoidea (Trichoptera) with the establishment of three new families

We inferred the phylogenetic relationships among 58 genera of Sericostomatoidea, representing all previously accepted families as well as genera that were not placed in established families. The analyses were based on five fragments of the protein coding genes carbamoylphosphate synthetase (CPSase of CAD), isocitrate dehydrogenase (IDH), Elongation factor 1a (EF‐1a), RNA polymerase II (POL II) and cytochrome oxidase I (COI). The data set was analysed using Bayesian methods with a mixed model, raxml , and parsimony. The various methods generated slightly different results regarding relationships among families, but the shared results comprise support for: (i) a monophyletic Sericostomatoidea; (ii) a paraphyletic Parasericostoma due to inclusion of Myotrichia murina, leading to synonymization of Myotrichia with Parasericostoma; (iii) a polyphyletic Sericostomatidae, which is divided into two families, Sericostomatidae sensu stricto and Parasericostomatidae fam.n. ; (iv) a polyphyletic Helicophidae which is divided into Helicophidae sensu stricto and Heloccabucidae fam.n. ; (v) hypothesized phylogenetic placement of the former incerta sedis genera Ngoya, Seselpsyche and Karomana; (vi) a paraphyletic Costora (Conoesucidae) that should be divided into several genera after more careful examination of morphological data; (vii) reinstatement of Gyrocarisa as a valid genus within Petrothrincidae. A third family, Ceylanopsychidae fam.n. , is established based on morphological characters alone. A hypothesis of the relationship among 14 of the 15 families in the superfamily is presented. A key to the families is presented based on adults (males). Taxonomic history, diagnosis, habitat preference and distribution data for all sericostomatoid families are presented. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:CF6A6B9F‐6A72‐4265‐BD09‐3A710DFCD7B1 .     

Changes in Gibberellin-Like Substances and Indole-3-Acetic Acid in Picea abies during the Period of Shoot Elongation

Grafted clones of Picea abies (L.) Karst. were used for the study. A very rapid and conspicuous rise in the content of gibberellin-like substances chromatographically similar to gibberellin A₁, and of indole-3-acetic acid, occurred during the brief period of most rapid shoot elongation. A few days later, when the shoot growth had terminated, very small amounts of both compounds could be detected. The changes in the qualitative pattern of gibberellin-like substances were consistent with a suggested interconversion pathway leading from non-polar to increasingly polar compounds     

The Natural Host Range of Steinernema and Heterorhabditis spp. and Their Impact on Insect Populations

The natural host range of entomopathogenic nematodes of the genera Steinernema and Heterorhabditis can be defined as the range of insects which indigenous nematode populations use for propagation. Information on the natural host range is rare. However, based on records of insects found to be naturally infected with nematodes, some conclusions regarding the natural host range of some Steinernema spp. and Heterorhabditis spp. are presented. Reports of indigenous nematode populations impacting on insect populations can be divided between relatively balanced, long-lasting nematode-host associations and unbalanced, short-lasting epizootics. Examples of the augmentation and inoculative introduction of nematodes in agriculture and forestry ecosystems are presented. Based on current knowledge, nematode reproduction strategies are discussed and indications of the risk involved in the release of non-indigenous nematodes are given.     

Common Cuckoo Cuculus canorus and host behaviour at Reed Warbler Acrocephalus scirpaceus nests

This study is based on continuous video recordings made at 53 Reed Warbler Acrocephalus scirpaceus nests each day during the laying period. Egg-laying by the Common Cuckoo Cuculus canorus was recorded in 14 (26.4%) of these nests. By analysing the activity of the host birds around and at the nest, we found that this is probably not the only cue used by the Common Cuckoo when locating suitable nests to parasitize. Furthermore, in most cases there was no significant difference between the length of time the host birds spent at the nest in the morning and afternoon, thus providing little support for the hypothesis that the Common Cuckoo lays in the afternoon because it is less likely to be seen by the nest owners then. Parasitized Reed Warblers rejected the Common Cuckoo egg more frequently when they observed the parasite at their nests. However, contrary to what should be expected, most Common Cuckoos laid their eggs in the presence of the host(s), and in general their egg-laying behaviour (for example duration of stay at the nest) was less secretive than described earlier. When partially depredating host clutches, Cuckoos showed the same behavioural pattern at parasitized and unparasitized nests, indicating that the latter may act as a potential reserve for egg-laying.     

The tribal position of Oedera L. (Compositae)

l position of Oedera L. (Compositae). The South African genus Oedera L. (Compositae-Anthemideae) is shown to be closely related to the South African genera Relhania and Leysera . A transfer of Oedera from the tribe Anthemideae to the tribe Inuleae is proposed. Several synapomorphies, like a two-layered sexine, concave leaves, pappus of connate scales, long and slender cypselas define the monophyletic group. The pollen-wall morphology of Oedera is described and the chromosome number 2 n = 14 is reported.     

Rapid northwards expansion of a forest insect pest attributed to spring phenology matching with sub‐Arctic birch

Species range displacements owing to shifts in temporal associations between trophic levels are expected consequences of climate warming. Climate‐induced range expansions have been shown for two irruptive forest defoliators, the geometrids Operophtera brumata and Epirrita autumnata, causing more extensive forest damage in sub‐Arctic Fennoscandia. Here, we document a rapid northwards expansion of a novel irruptive geometrid, Agriopis aurantiaria, into the same region, with the aim of providing insights into mechanisms underlying the recent geometrid range expansions and subsequent forest damage. Based on regional scale data on occurrences and a quantitative monitoring of population densities along the invasion front, we show that, since the first records of larval specimens in the region in 1997–1998, the species has spread northwards to approximately 70°N, and caused severe defoliation locally during 2004–2006. Through targeted studies of larval phenology of A. aurantiaria and O. brumata, as well as spring phenology of birch, along meso‐scale climatic gradients, we show that A. aurantiaria displays a similar dynamics and development as O. brumata, albeit with a consistent phenological lag of 0.75–1 instar. Experiments of the temperature requirements for egg hatching and for budburst in birch showed that this phenological lag is caused by delayed egg hatching in A. aurantiaria relative to O. brumata. A. aurantiaria had a higher development threshold (LDT_A.a.=4.71 °C, LDT_O.b.=1.41 °C), and hatched later and in less synchrony with budburst than O. brumata at the lower end of the studied temperature range. We can conclude that recent warmer springs have provided phenological match between A. aurantiaria and sub‐Arctic birch which may intensify the cumulative impact of geometrid outbreaks on this forest ecosystem. Higher spring temperatures will increase spring phenological synchrony between A. aurantiaria and its host, which suggests that a further expansion of the outbreak range of A. aurantiaria can be expected.     

Culturing of stoneworts and submersed angiosperms with phosphate uptake exclusively from an artificial sediment

1. We aimed to demonstrate reproducible nutrition and growth of macrophytes in non‐axenic laboratory cultures preventing growth of phytoplankton and epiphytes. 2. Macrophyte shoot segments were planted in a mixture of commercial acid‐washed silica sand with crystalline tricalcium phosphate, and this artificial sediment was covered with a layer of pure silica sand. The liquid mineral media used did not contain phosphorus but were rich in all other nutrient elements. A CO₂ reservoir provided sustainable CO₂ supply to macrophyte cultures by gas diffusion through a polyethylene membrane. 3. Chara hispida, Chara tomentosa, Chara baltica, Elodea canadensis, Potamogeton pectinatus and Zanichellia palustris could be cultivated for long term without medium exchange and aeration. Microalgae growth was prevented by the absence of phosphate in the water column. Mobilisation of tricalcium phosphate and phosphate uptake by the rhizoids of C. hispida enabled sustainable rapid shoot growth and increased the concentration of inorganic phosphate in the shoot dry weight by five to six times in comparison with plants cultivated on pure silica sand. A significant growth support from tricalcium phosphate was also observed for E. canadensis, but the rate of phosphate uptake by the roots was not sufficient to maintain a storage pool of inorganic phosphate (P_i) in the growing shoots of this plant. 4. Membrane‐controlled CO₂ supply from a reservoir and artificial sediments like the one described provide attractive options for the laboratory culture of macrophytes.     

Competitive exclusion along climate gradients: energy efficiency influences the distribution of two salmonid fishes

We tested the importance of thermal adaptations and energy efficiency in relation to the geographical distribution of two competing freshwater salmonid fish species. Presence–absence data for Arctic char and brown trout were obtained from 1502 Norwegian lakes embracing both temperature and productivity gradients. The distributions were contrasted with laboratory‐derived temperature scaling models for food consumption, growth and energy efficiency. Thermal performances of the two species were almost identical. However, Arctic char exhibited double the growth efficiency (per unit of food) and appear to have out‐competed brown trout from cold, low‐productivity lakes, perhaps by scramble competition. Brown trout, for which previous reports have shown to be aggressive and dominant, have likely excluded the more energy‐efficient Arctic char from relatively warm, productive lakes, perhaps by contest competition. Competitive interaction changing in outcome with lake productivity, rather than thermal performance, is likely a major determinant of the range distribution of the two species. Our study highlights the need for more focus on choice of relevant ecophysiological traits in ecological climate impact studies and species distribution modelling.     

When the pond turtle followed the reindeer: effect of the last extreme global warming event on the timing of faunal change in Northern Europe

Faunal communities have been shaped in different ways by past climatic change. The impact of the termination of the last Glacial and the onset of the present (Holocene) Interglacial on large‐scale faunal shifts, extinction dynamics and gene pools of species are of special interest in natural sciences. A general pattern of climate‐triggered range expansion and local extinction of vertebrate species is known for Europe, and shows that in the modern temperate zone the main faunal change took place mainly during the Late Glacial (14 700–11 700 years ago) and Early Holocene (11 700–9 100 years ago). Based on large datasets of new radiocarbon data, we present precise temporal dynamics of climate‐driven disappearance and appearance of reindeer and pond turtle in southern Sweden. These two species are significant climate indicators in Late Quaternary biostratigraphy. Our data reveal that the reindeer disappeared from southern Sweden ca. 10 300 years ago, whereas the pond turtle colonized the area ca. 9 860 years ago, with a 450‐year gap between each species. This provides evidence for a sudden environmental turnover, causing the replacement of an arctic faunal element by a thermophilic species. The postglacial range dynamics of pond turtle and reindeer are a unique model case, allowing insights into the faunal turnover of other vertebrates during the last dramatic natural global warming event at the Pleistocene–Holocene transition.