Crane Fly Larvae Research Articles

Calcium and strontium stable isotopes reveal similar behaviors of essential Ca and nonessential Sr in stream food webs

AbstractRecent studies showed the potential of stable isotopes of the macronutrient calcium (δ44/40Ca) and nonessential strontium (δ88/86Sr) as new trophic level indicators in terrestrial vertebrates and marine teleost fishes. In this study, we tested whether similar Ca and Sr isotopic fractionation trends existed in macroinvertebrate‐dominated stream food webs compared to vertebrates despite their physiological differences. We have determined the δ44/40Ca and δ88/86Sr values as well as the 87Sr/86Sr ratios of stream macroinvertebrates and small gobies and their potential metal sources (stream water, periphyton, and terrestrial plant litter) in upper and lower reaches of two streams in the Lake Biwa catchment, central Japan. The 87Sr/86Sr ratios revealed that stonefly nymphs, crustacea, and gobies mostly relied on aquatic Sr sources. Higher 87Sr/86Sr ratios of some crane fly and caddisfly larvae, mayfly, dobsonfly, and dragonfly nymphs indicated greater terrestrial contributions via plant litter. Positive correlations between the δ44/40Ca and δ88/86Sr values implied that similar Ca and Sr sources existed, and that Ca and Sr stable isotopes underwent similar fractionation trends although Sr was not essential. The δ44/40Ca and partly the δ88/86Sr values were positively correlated with Sr/Ca ratios and negatively with δ15N values indicating trophic effects on Ca and Sr stable isotopes. The enrichment of 44Ca and 88Sr in large filter‐feeding caddisfly larvae was a notable exception from these trophic trends. Our data confirm that the trophic 44Ca and 88Sr depletion observed for marine teleost fishes and terrestrial vertebrates also applied to macroinvertebrate‐dominated stream food webs despite their different physiologies indicating that shared mechanisms of Ca and Sr isotopic fractionation may exist at the cellular or molecular level between these taxa.

Abundance and diversity of insects associated with dry fish spoilage in three (3) selected markets in Yenagoa, Bayelsa State

The insect vectors associated with spoilage of dried fish in Yenagoa were studied. This was done in order to identify the diversity and abundance of Insects implicated in fish spoilage in order to suggest alternate storage means. Insect infested dry fish samples were procured from Three (3) markets (Swali (A), Kpansia (B) and Tombia (C)) and put into clean transparent plastic containers covered with little nets. They were moistened every day with water sprinkled into the containers for 1 week for insects to emerge. Insect vectors were identified to species level using standard keys. Result of the investigation reveal that a total of eleven Taxa and 156 individuals were found: 12 Calliphorid larvae, 1 crane fly larvae, 46 Musca domestica larvae, 5 Phaenicia sericate, 20 Piophilia casei, 20 Calliphorid pupa, 3 Tephritid larvae, 6 Necrobia fufipe larvae, 10 Dermestes maculatus pupae, 30 Phlorid pupa, 3 scatopsidae larvae. The dominant taxon was Musca domestica larvae followed by Phlorid pupa, and the least abundant was crane fly larvae. From the eleven (11) taxa seen, the abundance of Phlorid pupa was observed in station C (30). Piophilia casei and Musca domestica larvae were the only taxa present in the three sample stations. The Shannon index gotten in station B varied from station A and C. Shannon diversity index for station B was observed to be 1.535 and A and C were observed to be 0.918 and 1.466 respectively. Species evenness was greatest at station A (0.835). The insect vector of the order coleoptera (Beetles) were present only in fish samples from Swali and Tombia markets and absent from fish samples from Kpansia market. This may be due to the storage methods for dry fish in these markets and also due to environmental factors prevalent in these markets. The dominance of Musca domestica is indicative of possible health hazards as the consumption of insect infested dried fish in Yenagoa without washing may result in cholera and diarrhea. The study concluded that insects are the major vector pathogens causing spoilage in dried fish in Yenagoa, as indicated in similar studies in the Niger Delta. Therefore, more effort should be taken in the preservation and storage of dry fish to ensure food safety and security.

Preliminary study of the benthic fauna in lakes of the Novaya Zemlya Archipelago and Vaigach Island (the Russian Arctic)

The biodiversity of freshwater fauna of the Arctic Islands of the Russian Federation is currently poorly studied and to date there are insufficient molecular genetic data concerning most of the taxa. This study presents the new data on species composition and distribution of freshwater benthic invertebrates in lakes of the Novaya Zemlya Archipelago and Vaigach Island based on both the published and the original records. A total of 29 species of invertebrates in 4 classes and 14 orders were found. Considering the published data, the list of species expands to 136 species. The copepod Mesocyclops leuckarti, the pontoporeid amphipod Monoporeia affinis, the ostracod Leucocythere mirabilis, and the mollusk Euglesa globularis were recorded for the first time from the Novaya Zemlya Archipelago. The oligochaete Rhyacodrilus coccineus, the stonefly Nemoura sahlbergi, the caddisflies Agrypnia obsoleta, Micrasema gelidum and Philarctus bergrothi were registered for the first time from Vaigach Island; P. bergrothi was also recorded for the first time from Europe. The crane fly larvae of Tipula (Arctotipula) were recorded as inhabitants of the bottom layer of Arctic lakes for the first time. The obtained molecular data are in accordance with the tabula rasa hypothesis that the invertebrate fauna of the Novaya Zemlya Archipelago and Vaigach Island are the result of recent species immigration after the Last Glacial Maximum. Our data can be used in further ecological studies and conservation management. The molecular data are of considerable interest for the taxonomy and biogeography of the fauna of the Arctic islands during the Pleistocene.

Moss mimesispar excellence: integrating previous and new data on the life history and larval ecomorphology of long-bodied craneflies (Diptera: Cylindrotomidae: Cylindrotominae)

AbstractDifferent physical structures play a central role in animal camouflage. However, in evolutionary studies of mimicry, the ecological and evolutionary significance of such structures has been poorly investigated. Larvae of long-bodied craneflies, Cylindrotominae, are all obligate herbivores and resemble plants. They are distinctively characterized by possessing numerous elongated cuticular lobes on the integument. A comprehensive overview of the biology and morphology of cylindrotomids, particularly their larval stages, is laid out, providing original data on nine species. To explore the ecological background of moss resemblance, host-plants of most examined species are clarified, revealing that terrestrial moss-feeding species tend to use specific groups of mosses, either belonging to Bryales or Hypnales. However, the evolution of cryptic forms remains paradoxical, due to the apparent absence of visual predators. Based on histological examinations, extensive internal musculatures within the cuticular lobes on the lateral side are discovered, shedding new light on their function in locomotion. Traditional functional explanations for these lobes, particularly as devices for respiration, locomotion and attachment, are challenged. This study promotes our understanding of the ecomorphology of mimicry devices, which is an angle often dismissed in evolutionary studies of mimicry.

Magnesium and zinc stable isotopes as a new tool to understand Mg and Zn sources in stream food webs

AbstractNon‐traditional stable isotopes of metals were recently shown as new dietary tracers in terrestrial and marine mammals. Whether these metal stable isotopes can be used to understand feeding habits in stream food webs is not known yet. In this study, we explored the potential of stable isotopes of essential Mg (δ26Mg) and Zn (δ66Zn) as a new tool in stream ecology. For this purpose, we determined δ26Mg and δ66Zn values of stream organisms and their potential metal sources in upper and lower reaches of two streams in the Lake Biwa catchment, Central Japan. Our goals were (1) to explore variations in δ26Mg and δ66Zn across organisms of different feeding habits and (2) to understand Mg and Zn sources to stream organisms. Overall, δ26Mg and δ66Zn values of organisms were neither related to each other, nor to δ13C and δ15N values, indicating different elemental sources and factors controlling isotopic fractionation depending on element and taxa. Low δ26Mg values in filter‐feeding caddisfly larvae and small gobies indicated aqueous Mg uptake. Higher δ26Mg values in leaf‐shredding crane fly and grazing mayfly larvae suggested Mg isotopic fractionation during Mg uptake from the diet. While the δ26Mg values of stonefly nymphs reflected those of caddisfly larvae as a potential prey, the highest δ26Mg values found in dobsonfly nymphs can be explained by 26Mg enrichment during maturing. δ66Zn values of caddisfly and mayfly larvae indicated Zn was a mixture of aqueous and dietary available Zn, while higher δ66Zn values in crane fly larvae pointed to Zn isotopic fractionation during Zn uptake from plant litter. δ66Zn values in stonefly and dobsonfly nymphs were often in the range of those of caddisfly larvae as their prey, while dragonfly nymphs and small goby were depleted in 66Zn relative to their dietary Zn sources. We conclude that δ26Mg is a promising indicator to assess Mg sources in stream ecology depending on taxa, while the use of δ66Zn is limited due to the complexity in Zn sources.

Mercury and selenium loading in mountaintop mining impacted alkaline streams and riparian food webs

Coal is naturally enriched in trace elements, including mercury (Hg) and selenium (Se). Alkaline mine drainage from mountaintop mining valley fill (MTM-VF)—the dominant form of surface coal mining in Appalachia, USA—releases large quantities of Se into streams draining mined catchments, resulting in elevated bioaccumulation of Se in aquatic and riparian organisms. Yet, the release of Hg into these streams from MTM-VF has not yet been studied. We measured total Hg, methylmercury (MeHg), and Se in stream water, sediment, biofilm, cranefly larvae, and riparian spiders in alkaline streams (pH range 6.9–8.4) across a mining gradient (0–98% watershed mined) in central Appalachia. Hg concentrations ranged from below detection limit (BDL)-6.9 ng/L in unfiltered water, BDL-0.05 µg/g in bulk sediment, 0.016–0.098 µg/g in biofilm, 0.038–0.11 µg/g in cranefly larvae, and 0.046–0.25 µg/g in riparian spiders. In contrast to Se, we found that Hg concentrations in all environmental compartments were not related to the proportion of the watershed mined, suggesting that Hg is not being released from, nor bioaccumulating within, MTM-VF watersheds. We also did not find clear evidence for a reduction in Hg methylation or bioaccumulation under elevated Se concentrations: water, sediment, biofilm, and riparian spiders exhibited no relationship between Hg and Se; only cranefly larvae exhibited a negative relationship (p = 0.0002, r2 = 0.42). We suggest that the type of surface mining matrix rock, with resultant alkaline or acid mine drainage, is important for the speciation, mobility, and bioaccumulation of trace elements within watersheds affected by mining activities.

Thermal tolerances and species interactions determine the elevational distributions of insects

AbstractAimPhysiological limits to thermal extremes are often thought to determine the abundance and geographical distribution of species, but more recent evidence suggests that species interactions might be equally important. Moreover, the relative importance of these constraints might shift with changing abiotic conditions, such as climate change. Here, we explore the relative importance of physiological tolerances to heat and species interactions in determining the distribution of insects along two elevational gradients. The gradients contrast in precipitation but not temperature, allowing us to separate these two climatic factors.LocationMontane rainforest in Costa Rica.Time period2015–2016.Major taxa studiedBromeliad‐dwelling aquatic insect larvae.MethodsWe estimated the elevational preferences of five insect taxa by surveying 170 bromeliads along the moist Atlantic and the dry Pacific slopes of Monteverde and determined their critical thermal maxima (CTmax) experimentally. We determined whether taxon‐specific heat tolerances predicted their elevational preferences, using Deming regressions, and tested whether potential predators mediated effects on the elevation of insect distributions, using structural equation models.ResultsOn the moist Atlantic slope, heat tolerances of insects explained their elevational distributions: taxa with high heat tolerances preferred low elevations where conditions were warmest, whereas taxa with low heat tolerances preferred high elevations where conditions were coldest. In contrast, on the drier Pacific slope, the elevational abundance pattern of many insects reflected negative interactions from crane fly larvae. These larvae are known to become predatory in drought conditions and were disproportionally abundant at low elevations on the Pacific slope.Main conclusionsWe show that under drought, indirect effects mediated by species interactions can override any direct physiological effects of environmental conditions on insect distributions. The relative importance of limits to physiological tolerance and species interactions thus depends on the environmental context, an important insight given that environmental conditions are expected to shift with climate change.

Microbial Nitrogen Fixation in the Intestine of Tipulidae Tipula maxima Larvae

Nitrogen-fixing activity of microorganisms in the intestines of Crane fly (Tipulidae) larvae and their influence on the processes of microbial nitrogen fixation in soil have been studied. Two independent methods have shown high rates of nitrogenase activity in the digestive tract of larvae, which is determined mainly by transit nitrogen-fixing microorganisms. Nitrogen fixers actively developing in the intestines of larvae stimulate a sharp increase in nitrogenase activity in the soil: after 3 months of incubation, the activity increases eightfold; it can contribute to the accumulation of nitrogen in the habitats of the larvae.

Fruit‐ and seed‐feeding habit of the crane fly Libnotes puella (Diptera: Limoniidae) in Ryukyu Islands, Japan

AbstractAlthough most crane fly larvae consume decaying plant materials and their associated microorganisms, all Libnotes species investigated so far are known to be xylophilous insects. Here we report the novel herbivorous feeding ecology of Libnotes puella. We found that L. puella larvae consumed the fruits or seeds of three unrelated plants, Mitrastemon yamamotoi (Mitrastemonaceae), Balanophora tobiracola (Balanophoraceae) and Barringtonia racemosa (Lecythidaceae). The larvae live within dense tubes formed by their feces fastened by their mucous excretions at the final stage, and they pupate within such tubes. This is the first detailed documentation of the fruit‐ and seed‐feeding habit of crane flies.

Effect of Vital Activity of Soil-Dwelling Tipulid (Tipula maxima) Larvae on Biological Activity in the Soil

The effect of crane fly (Diptera, Tipulidae) larvae on the functional diversity of soil microorganism communities and the intensity of nitrogen and carbon transformation processes in soil has been investigated. The vital activity of larvae in the soil has been shown to significantly accelerate nitrogen fixation, denitrification, and methane production and elevate the functional diversity (the number of substrates consumed and metabolic work) and stability of the microbial complex.

Sediment and biota trace element distribution in streams disturbed by upland industrial activity.

Extensive industrial areas in headwater stream watersheds can severely impact the physical condition of streams and introduce contaminants. We compared 3 streams that received stormwater runoff and industrial effluents from industrial complexes to 2 reference streams. Reference streams provide a benchmark of comparison of geomorphic form and stability in coastal plain, sandy-bottomed streams as well as concentrations of trace elements in sediment and biota in the absence of industrial disturbance. We used crayfish (Cambarus latimanus, Procambarus raneyi, Procambarus acutus) and crane fly larvae (Tipula) as biomonitors of 15 trace elements entering aquatic food webs. Streams with industrial areas were more scoured, deeply incised, and less stable. Sediment organic matter content broadly correlated to trace element accumulation, but fine sediments and organic matter were scoured from the bottoms of disturbed streams. Trace element concentrations were higher in depositional zones than runs within all streams. Despite contaminant sources in the headwaters, trace element concentrations were generally not elevated in sediments of the eroded streams. However, element concentrations were frequently elevated in biota from these streams with taxonomic differences in accumulation amplified. In eroded, sand-bottomed coastal plain streams with unstable sediments, single snapshots of sediment trace element concentrations did not characterize well bioavailable trace elements. Biota that integrated exposures over time and space within their home ranges better detected bioavailable contaminants than sediment. Environ Toxicol Chem 2019;38:115-131. © 2018 SETAC.

Molecular identification and distribution of leatherjackets (Diptera: Tipulidae) in U.K. agricultural grassland

Abstract DNA barcoding is useful for the identification of morphologically cryptic invertebrates. An important application is for pest species, for which it is critical to determine the distribution, biology and ecology of damaging life stages in order to target management effectively. Tipula paludosa (Meigen) and Tipula oleracea (Linnaeus) leatherjackets, the larvae of crane flies (Diptera: Tipulidae), are pests of agricultural grassland in Europe and the U.S.A. and are difficult to distinguish morphologically. We used cytochrome c oxidase subunit I (COI) barcoding to identify leatherjackets from 19 permanent grassland fields over 2 sampling seasons on the Rothamsted Research North Wyke Farm Platform, south west UK, to assess species-level distribution and genetic diversity. Most larvae (94%) were found to be T. paludosa, comprising 18 haplotypes that were spread across the sampling site in a panmictic population. However, T. oleracea were found in low abundance (3% of larval samples) and only in the second year of sampling. Other morphologically similar Dipteran larvae (3%) were also found. This dominance of one species suggests that there may be underlying differences in species biology, such as choice of oviposition site and dispersal ability, which is in agreement with other studies and has implications for monitoring and management.

Declines in diversity of crane flies (Diptera: Tipuloidea) indicate impact from grazing by livestock in the Hövsgöl region of Mongolia

Threats to biodiversity are not studied equally amongst taxa leaving some groups like insects typically understudied in conservation and management research. Crane flies (Diptera: Tipuloidea) are diverse and important members of the aquatic and terrestrial biotic communities. These semi-terrestrial larval habitat preferences place crane flies at risk of habitat degradation and loss particularly from grazing by livestock. Increased grazing by livestock in the Hovsgol region of Mongolia has impacted both terrestrial and aquatic ecosystems. The purpose of this study is to document biodiversity of crane flies along the east shore of Lake Hovsgol, Mongolia, and to test whether crane fly diversity differs between valleys with different grazing intensity. Ninety-six species of Tipuloidea were found in this study, nine of these new to Mongolia, with 21 new to the Hovsgol region. Rarefaction curves indicate that predicted diversity is less for moderately and highly grazed valleys than for the lightly grazed valleys and an analysis of variance indicates that Shannon’s diversity index was significantly higher in the lightly grazed valleys. Finally, a parsimonious model based on multiple regression analysis indicates that plant biomass and relative humidity are the strongest significant predicators of variation in crane fly diversity across the grazing gradient. Since crane fly larvae are an important part of the soil and leaf litter community, impaired diversity may affect ecosystem services such as decomposition of leaf litter and bioturbation, potentially exacerbating the impact of grazing.

The genome of the nucleopolyhedrosis-causing virus from Tipula oleracea sheds new light on the Nudiviridae family.

A large double-stranded DNA (dsDNA) virus that produces occlusion bodies, typical of baculoviruses, has been described to infect crane fly larvae of the genus Tipula (Diptera, Tipulidae). Because of a lack of genomic data, this virus has remained unclassified. Electron microscopy of an archival virus isolated from Tipula oleracea, T. oleracea nudivirus (ToNV), showed irregularly shaped occlusion bodies measuring from 2 to 5 μm in length and 2 μm in middiameter, filled with rod-shape virions containing single nucleocapsids within a bilayer envelope. Whole-genome amplification and Roche 454 sequencing revealed a complete circular genome sequence of 145.7 kb, containing five direct repeat regions. We predicted 131 open reading frames, including a homolog of the polyhedrin gene encoding the major occlusion body protein of T. paludosa nucleopolyhedrovirus (NPV). BLAST searches demonstrated that ToNV had 21 of the 37 baculovirus core genes but shared 52 genes with nudiviruses (NVs). Phylogenomic analyses indicated that ToNV clearly belongs to the Nudiviridae family but should probably be assigned to a new genus. Among nudiviruses, ToNV was most closely related to the Penaeus monodon NV and Heliothis zea NV clade but distantly related to Drosophila innubia NV, the other nudivirus infecting a Diptera. Lastly, ToNV was found to be most closely related to the nuvidirus ancestor of bracoviruses. This was also reflected in terms of gene content, as ToNV was the only known exogenous virus harboring homologs of the Cc50C22.6 and 27b (Cc50C22.7) genes found in the nudiviral genomic cluster involved in bracovirus particle production. The Nudiviridae is a family of arthropod dsDNA viruses from which striking cases of endogenization have been reported (i.e., symbiotic bracoviruses deriving from a nudivirus and the endogenous nudivirus of the brown planthopper). Although related to baculoviruses, relatively little is known about the genomic diversity of exogenous nudiviruses. Here, we characterized, morphologically and genetically, an archival sample of the Tipula oleracea nudivirus (ToNV), which has the particularity of forming occlusion bodies. Comparative genomic and phylogenomic analyses showed ToNV to be to date the closest known relative of the exogenous ancestor of bracoviruses and that ToNV should be assigned to a new genus. Moreover, we revised the homology relationships of nudiviral genes and identified a new set of 32 core genes for the Nudiviridae, of which 21 were also baculovirus core genes. These findings provide important insights into the evolutionary history of large arthropod dsDNA viruses.

The spatial distribution of phytophagous insect larvae in grassland soils

Most research on soil dwelling phytophagous insect larvae has arisen from their functional roles as pests in agricultural systems, but few studies have considered their spatial distribution or the possible interactions between taxa, and none have investigated the effect of scale. In this study the individual and interspecific spatial distribution of wireworms (click beetle larvae – Elateridae), leatherjackets (crane fly larvae – Tipulidae), bibionid flies (Bibionidae) and sciarid flies (Sciaridae) over three scales, and the importance of spatial, biotic and scale variables, was assessed. Soil core samples were collected from 26 sites across six grass fields on a farm in South Devon, UK. Abundance and presence-absence data were analysed over the field, site and soil core scales using variance/mean ratio and non-metric multidimensional scaling (NMDS), and deviance partitioning was used to determine the importance of spatial, biotic and scale variables for individual taxa distribution. The spatial distribution of most taxa changed from an aggregated to a random distribution from the field to the core scale. Interspecific distributions of taxa also differed between scales, though some associations held at all scales. Deviance partitioning revealed that scale was the single most important variable influencing taxa distribution, whereas spatial and biotic variables were mostly of minor importance. The results suggest that variation between taxa is likely to be due to interactions between scale-specific environmental, biotic and stochastic factors and individual taxon biology, and emphasises the need to take scale into account when interpreting data from ecological studies.

Ultrastructure and life history of Myolaimus byersi n. sp. (Myolaimina: Myolaimidae), a phoretic associate of the crane fly, Limonia schwarzi (Alexander) (Limoniidae), in Florida

Abstract Myolaimus byersi n. sp., a phoretic associate of the crane fly, Limonia (Rhipidia) schwarzi (Diptera: Limoniidae), was recovered from moist and decaying tissue from the crown shaft of a living spindle palm, Hyophorbe verschaffeltii, in southern Florida and is described herein. Dauers were carried in the abdominal folds of male and female L. schwarzi. Examination of the highly mobile crane fly larvae and pupae confirmed that the dauers were externally associated with the cuticle. Dauers from crane flies were culturable to adults on 1/20 strength TSB agar. The association appears to be relatively host specific. SEM studies, early embryonic development, dauers, molecular data and TEM ultrastructural comparisons of the stoma, sensory structures and sperm are used to discuss the relative placement of Myolaimus within the Nematoda. The stoma resembles diplogastrids in being strongly anisomorphic with an enlarged dorsal sector of the stegostom, yet also resembles rhabditids in having three triangular flaps in the metastegostom and matches cephalobs and panagrolaims in having a pharyngeal collar with two sets of three interradial muscles followed by two sets of six adradial muscles. The ultrastructure of the cheilostom epidermis shows a high degree of conservation with several Rhabditida. The sperm of M. byersi n. sp. is nearly identical to that of Caenorhabditis elegans. In early cell division, M. byersi n. sp. is closest to Parascaris equorum followed by C. elegans. Myolaimus apparently represents a divergent lineage that has followed a non-coalescing trajectory for a long time, allowing it to retain some highly conserved characters while also developing some surprisingly unique features, such as a baggy cuticle and males that lack a gubernaculum or spicules.

Morphological characterization of solute flow in a brown earth grassland soil with cranefly larvae burrows (leatherjackets)

Cranefly larvae, often known as leatherjackets, are a well known horticultural pest, damaging garden lawns, plants and sporting venues. They burrow into the soil and feed on the roots of plants. However, little is known about the hydrological role of leatherjackets. Such information is needed by modellers to improve water and solute models. This paper investigates flow through leatherjacket burrows in grassland fields. It compares infiltration rates, patterns of dye tracer and pore size distributions in a grassland system with and without leatherjackets. It also compares these distributions to those in an adjacent cropped tillage system which was largely devoid of leatherjackets. Dye tracer distributions show the leatherjacket burrows to act as active preferential flowpaths for water during percolation. A significant relationship between leatherjacket density and infiltration rate was found which took the form of an exponential curve. Leatherjackets were predominately found in the upper 30 cm of the grassland where there was a significantly greater volume of pores that were greater than 2 mm than in the arable soil and where visible macropores, including those open to the surface were significantly more common, covered a significantly larger cross-sectional area and were more circular in cross-sectional area. Leatherjacket burrows significantly reduced the spread of water into the surrounding soil and thereby acted as effective conduits for water to bypass the soil matrix in the upper 30 cm of the grassland. Mean dye coverage was greater at between 30 and 36 cm in the grassland soil profile, where leatherjacket burrows ended, than any other parts of the soil profile deeper than 8 cm. Such dye distributions were rare in the arable soils where very few leatherjackets were present. In some regions fallow grassland is increasing in area in response to environmental policy. Therefore, since infiltration significantly increased with leatherjacket density, consideration of their role in macropore flow will be necessary to understand the full range of hydrological and water quality implications of conversion from arable to fallow grassland management.

Decomposition Rate and Community Structure of Leaf-packs in an Urban and Rural Stream in Southwestern Missouri

Previous studies demonstrated significantly lower diversity and density of aquatic invertebrates in a southwestern Missouri urban stream, Turkey Creek, below a large mall in comparison to above mall sites and a rural stream, Jones Creek. Such invertebrate declines might affect leaf decomposition rates in these streams. We estimated decomposition rate and macro-invertebrate community structure using experimental leaf-packs composed of freshly dried red elm leaves. Thirty-six leaf-packs housed in polyester mesh (2 by 4 mm) bags were anchored in riffles at the three sites. Bags were recovered after 15 and 36 days, invertebrates were removed and identified, and leaf residue air dried. Decay rates as fraction lost/day after 15 days were 4.20%/day Turkey Creek above mall, 4.43%/day Turkey Creek below mall, and 4.45%/day at Jones Creek. After 36 days decay rates were 2.14%/day Turkey Creek above mall, 2.15% Turkey Creek below mall, and 2.36%/day Jones Creek. Rates were not significantly different between sites (ANOVA, P = 0.55 at 15 days and P = 0.23 at 36 days). Decay constants calculated by regressing % dry mass remaining and days in stream were −0.040/day for both Turkey Creek above and below mall and −0.056/day for Jones Creek. Shredders were primarily represented by the cranefly larvae Tipula abdominalis in both TC sites and by T abdominalis and the isopod Lirceus hoppinae in JC. Collector-gatherers, primarily net-spinning caddisflies Cheumatopsyche, Ceratopsyche, and Chimarra, as well as the dipteran family Chironomidae, numerically dominated leaf-packs. Leaf decomposition may be more related other factors, physical fragmentation, microbial processes, and seasonal differences in leaf abundance, than shredding in these streams. Dominance of collector-gatherers appears to indicate leaf-packs serve primarily as habitat and not a direct energy source for many stream macroinvertebrates.

Emergence of a new turfgrass insect pest on golf courses in Quebec, the European crane fly [Diptera: Tipulidae

A survey of European crane fly occurrence was performed in 2002 on 18 golf courses from different climatic regions of Quebec, Canada. At each golf course, the scouting was done weekly from early May to mid-October on three greens and three fairways using a grid and a golf course hole cutter, respectively. The European crane fly (Tipula paludosa), a major turfgrass insect pest, was identified on two golf courses in the Quebec City area. This is the first record of this species in Quebec. These European crane fly larvae were observed from mid-May to the end of August, and adults were detected from late August to mid-September. The European crane fly was found to be a pest on the two golf courses and insecticide applications were used to control the large populations of this insect.

Trichomycetes from China and the description of three new Smittium species

Trichomycetes were recovered from the guts of aquatic insect larvae collected from a stream in the Qinling Mountains in western China. These collections included Smittium hecatei, known only from Spain, as well as Smittium simulii and Stachylina penetralis, which appear to be more widely distributed. Caudomyces japonicus, previously recorded only from Japan, also is reported from crane fly larvae (Antocha sp.) from China. We describe three new species, Smittium chinliense from a tipulid host, as well as Smittium naiadis and Smittium nodifixum, both from chironomid larvae. A probable new species of Gauthieromyces was collected in mayfly nymphs and is illustrated but not described here.