Populations of all stages of three species of Hydropsychidae, Hydropsyche simulans, Cheumatopsyche campyla, and Cheumatopsyche lasia were sampled fro September, 1971, to August, 1972, on the Brazos River in Palo Pinto County, Texas. Supplemental observations relating to emergence, mating and oviposition, and larvae food habits were continued to July, 1973. The purpose of this study was to elucidate the life cycles and ecology of this Hydropsychidae complex.

Life history and annual production of Hydropsyche slossonae were determined in Mill Creek, Virginia, emphasizing aspects of its early life history. Mill Creek is a first—order stream in the Central Appalachian Ridges and Valleys ecoregion. Each adult female laid approximately 230 eggs in May and June which hatched in 13 days. Five larval instars were recorded with most individuals overwintering in III and IV instars. Pupation and emergence occurred primarily over a six week period in May and June. No mortality in the egg stage (0%) was detected, while high mortality in I instar (92.9%) was due in part to sibling cannibalism. Second through fifth instars showed constant, low mortality, with high mortality again in the pupal stage; an estimated 0.5% of the original eggs survived to adulthood. Growth analysis revealed two distinct growth phases; one from hatching through IV instar (0.008 mg/day) and a much faster growing V instar in May (0.085 mg/day). Annual production estimates ranged from 3 to 5 g/m² and were highly variable. It may be more precise to estimate production by predicting biomass from survivorship and growth functions than directly from sample data. On a per day basis, production was not constant but varied during the year. Yield per day peaked slightly later than peaks in production. High daily production occurred immediately after hatching due to growth of many small individuals. At the end of the generation, there was another period of high daily production due to fast growth by fewer larger individuals. Most production occurred from March through June. At other times, daily production was relatively low. / Ph. D.

Food habits, net-spinning activity, energetics, and mercury accumulation in Hydrospsyche morosa were examined over a one year period on the South River in central Virginia. Feeding nets were observed as early as April and were widespread by May. Nets were virtually absent from late November through March. Gut content analysis revealed seasonal patterns in the consumption of various food items. From April through October, when feeding nets were widespread, detritus formed the bulk of the diet in terms of both numbers of particles and volume occupied. From November through March however, the algal component dominated in terms of numbers of particles although the detritus component still occupied a greater volume. Ivlev's preference index was employed and indicated that the seasonal differences in the relative amount of the three food types were not simply a matter of changing seston concentrations, but rather suggested a shift from a filter-feeding mode of feeding in the summer months to grazing on diatoms in the winter. H. morosa was bivoltine on the South River. The estimate of secondary production for the summer cohort was 3,246 mg AFDW/m²/yr, while the estimate for the winter cohort was 2,145 mg AFDW/m²/yr. The secondary production also was estimated for each season based on food habits to determine the impact of the observed seasonal switch in feeding habits on production and egestion rates. During the summer, the detritus component contributed most to production averaging about 50 percent. Animal and algal material contributed 30 and 20 percent, respectively. During the winter, algal material contributed most to the production, averaging just over 62 percent. Detritus also contributed during the winter averaging over 30 percent. Monthly rates of production and egestion were between 3 and 3.5 times faster during the summer. The concentrations of total mercury in seston, periphyton, and in the body tissue of H. morosa were analyzed each month. Mercury concentrations were between four and six times higher in the seston than in the periphyton. The concentration of mercury in the body tissue of H. morasa ranged from 0.14 ppm in March to over 1.20 ppm in July. Differences in Mercury concentration in the insects between seasons were significant. Regression analysis revealed a significant relationship between Hg concentration in the insects and the relative amount of detritus found in the guts. / Master of Science

Through the use of natural history records, published literature, and personal sampling (2011-2016) a total of 454 caddisfly species represented by 24 families and 93 genera were documented from the south-central United States. Two Hydroptilidae species were collected during the 2011-2016 collection efforts that are new to the region: Hydroptilia scheringi and Mayatrichia tuscaloosa. Eightteen species are endemic and 30 are considered species of concern by either federal or state agencies. The majority of each of these groups is Hydroptilidae, or microcaddisflies. Trichoptera community structure, by minimum number of species, was analysed in conjunction with large-scale geographical factors to determine which factor illustrated caddisfly community structure across the region. Physiographic provinces compared to other geographic factors analyzed best-represented caddisfly communities with a minimum of 10 or more species. Statistically, Hydrologic Unit Code 4 (HUC 4) was the most significant geographical factor but low number of samples representing this variable rendered it less representative of caddisfly community structure for the study area.

No description available.

Caddisflies (Insecta, Trichoptera) is one of the most important group of benthic components in temperate freshwater ecosystems. They are sensitive to changes of physical and chemical parameters in water bodies, so often used to assess the ecological status of the water body. The main objective of this work was to investigate the caddisfly fauna, diversity, species distribution and rarity in Lithuania, to evaluate the influence of environmental factors on the distribution and abundance of caddisflies in different habitats of Lithuanian rivers. The results obtained supplement the knowledge of the fauna, diversity and distribution of caddisflies and other benthic invertebrate animals of Lithuanian rivers. The determined patterns of caddisfly distribution and abundance are important in optimizing biodiversity conservation measures. The results are important for improvement of methods for biotic assessment of ecological status of Lithuanian rivers. For the first time 22 new species of caddisfly were discovered and the checklist of Lithuanian caddisfly was updated. The relation between Lithuanian caddisfly distribution and abundance was determined. Seasonal flight periods for caddisfly adults and the factors influenting the flight dynamics were estimated. The environmental factors influencing the distribution and abundance of caddisfly taxa (families, genera, species) in Lithuanian rivers were detected. The significance of caddisflies in the communities of benthic invertebrates of... [to full text] / Apsiuvos (Insecta, Trichoptera) yra vienas svarbiausių vidutinio klimato gėlavandenių ekosistemų bentoso komponentų. Būdamos jautrios vandens telkinių fizinių ir cheminių parametrų pokyčiams, dažnai naudojamos vandens telkinių ekologinės būklės bioindikacijai. Gauti darbo rezultatai papildo žinias apie apsiuvų ir kitų bentoso bestuburių fauną, įvairovę, paplitimą ir gausumą Lietuvos upėse. Nustatyti apsiuvų paplitimo ir gausumo dėsningumai yra svarbūs optimizuojant bioįvairovės apsaugos priemones. Darbo rezultatai svarbūs tobulinant Lietuvos upių ekologinės būklės biotinio vertinimo metodus. Pirmą kartą buvo rastos 22 naujos apsiuvų rūšys ir atnaujintas Lietuvos apsiuvų faunos sąrašas. Nustatyta priklausomybė tarp Lietuvos apsiuvų paplitimo ir gausumo. Nustatyti apsiuvų suaugėlių sezoninio skraidymo tipai ir veiksniai kurie turi įtakos skraidymo dinamikai. Išaiškinti aplinkos veiksniai, kurie daro įtaką apsiuvų taksonų (šeimų, genčių, rūšių) paplitimui ir gausumui Lietuvos upėse. Įvertinta apsiuvų reikšmė skirtingų Lietuvos upių bentoso bestuburių bendrijų sudėtyje. Patikslintos apsiuvų taksonų bioindikacinės ypatybės Lietuvos sąlygomis ir pateiktos tekančių vandenų ekologinės būklės vertinimo rekomendacijos.

Apsiuvos (Insecta, Trichoptera) yra vienas svarbiausių vidutinio klimato gėlavandenių ekosistemų bentoso komponentų. Būdamos jautrios vandens telkinių fizinių ir cheminių parametrų pokyčiams, dažnai naudojamos vandens telkinių ekologinės būklės bioindikacijai. Gauti darbo rezultatai papildo žinias apie apsiuvų ir kitų bentoso bestuburių fauną, įvairovę, paplitimą ir gausumą Lietuvos upėse. Nustatyti apsiuvų paplitimo ir gausumo dėsningumai yra svarbūs optimizuojant bioįvairovės apsaugos priemones. Darbo rezultatai svarbūs tobulinant Lietuvos upių ekologinės būklės biotinio vertinimo metodus. Pirmą kartą buvo rastos 22 naujos apsiuvų rūšys ir atnaujintas Lietuvos apsiuvų faunos sąrašas. Nustatyta priklausomybė tarp Lietuvos apsiuvų paplitimo ir gausumo. Nustatyti apsiuvų suaugėlių sezoninio skraidymo tipai ir veiksniai kurie turi įtakos skraidymo dinamikai. Išaiškinti aplinkos veiksniai, kurie daro įtaką apsiuvų taksonų (šeimų, genčių, rūšių) paplitimui ir gausumui Lietuvos upėse. Įvertinta apsiuvų reikšmė skirtingų Lietuvos upių bentoso bestuburių bendrijų sudėtyje. Patikslintos apsiuvų taksonų bioindikacinės ypatybės Lietuvos sąlygomis ir pateiktos tekančių vandenų ekologinės būklės vertinimo rekomendacijos. / Caddisflies (Insecta, Trichoptera) is one of the most important group of benthic components in temperate freshwater ecosystems. They are sensitive to changes of physical and chemical parameters in water bodies, so often used to assess the ecological status of the water body. The main objective of this work was to investigate the caddisfly fauna, diversity, species distribution and rarity in Lithuania, to evaluate the influence of environmental factors on the distribution and abundance of caddisflies in different habitats of Lithuanian rivers. The results obtained supplement the knowledge of the fauna, diversity and distribution of caddisflies and other benthic invertebrate animals of Lithuanian rivers. The determined patterns of caddisfly distribution and abundance are important in optimizing biodiversity conservation measures. The results are important for improvement of methods for biotic assessment of ecological status of Lithuanian rivers. For the first time 22 new species of caddisfly were discovered and the checklist of Lithuanian caddisfly was updated. The relation between Lithuanian caddisfly distribution and abundance was determined. Seasonal flight periods for caddisfly adults and the factors influenting the flight dynamics were estimated. The environmental factors influencing the distribution and abundance of caddisfly taxa (families, genera, species) in Lithuanian rivers were detected. The significance of caddisflies in the communities of benthic invertebrates of... [to full text]

Thesis (Ph. D.)--University of Alabama at Birmingham, 2006. / Description based on contents viewed Jan. 26, 2007; title from title screen. Includes bibliographical references (p. 98-105).

The life history and case-building behavior of Molanna tryphena from two spring-fed tributaries in East Texas were studied from January 1997 to May 1998.

No description available.