TL;DR: The data suggest that disturbance frequency can directly influence the benthic community at the scale of individual rock "islands" by reducing invertebrate richness, total animal density, and periphyton biomass.
Abstract: Field experiments were conducted to examine the effects of disturbance frequency on invertebrates and periphyton colonizing bricks in a third order Rocky Mountain (USA) stream. After an initial colonization period (30 days), sets of bricks were turned over at intervals of 0, 3, 9, 27, or 54 days. Invertebrate species richness and density were reduced as disturbance frequency increased. These trends were evident for both seasons (summer and fall) and sites (open vs. closed canopy). Invertebrate species diversity (H′) displayed no effect during the fall experiment; however, H′ was reduced at high frequencies of disturbance during the summer experiment. Baetis tricaudatus was the most abundant invertebrate on the substrata at both sites and seasons. Alloperla, Baetis, Cinygmula, Chironomidae, Drunella grandis, Hydropsyche, and Seratella tibialis increased in absolute abundances as disturbance frequency decreased. Four other abundant taxa (Capnia, Cleptelmis, Glossosoma, and Isoperla) displayed no clear respo...
TL;DR: Three species of the family Perlodidae are newly reported or confirmed for China, Isoperla asiatica Raušer from Arxan, Inner Mongolia Autonomous Region, isoperla eximia Zapekina-Dulkeit from Changbai Mountain, Jilin Province, and Mesoperlina capnoptera from Xinjiang Uygur Aut autonomous Region.
Abstract: Three species of the family Perlodidae are newly reported or confirmed for China, Isoperla asiatica Rauser from Arxan, Inner Mongolia Autonomous Region, Isoperla eximia Zapekina-Dulkeit from Changbai Mountain, Jilin Province, and Mesoperlina capnoptera (McLachlan, 1886) from Xinjiang Uygur Autonomous Region Based on new material, additional taxonomic notes and images of another perlodid stonefly, Rauserodes epiproctalis (Zwick, 1997) is provided
TL;DR: A remarkable new species of Isoperla Banks, 1906, I. sextuberculata Huo Du, sp.
Abstract: A remarkable new species of Isoperla Banks, 1906, I sextuberculata Huo Du, sp nov from Hubei Province, Central China is described The new species is distinguished by the unique paired abdominal processes on male terga 4, 7, and 8 The new species is compared to similar Isoperlinae congeners
TL;DR: For the first time, morphological and molecular tools are used to delineate Isoperla species from the Balkans, a member of the I. tripartita group which is widely distributed in the Balkans.
Abstract: In this contribution, we describe Isoperla vjosae sp. nov. from Albania. We characterize males, females, and larvae of the new species collected at the Vjosa River using morphological and molecular approaches. Isoperla vjosae sp.nov. is a member of the I. tripartita group, which is widely distributed in the Balkans. This new endemic species is being threatened by a proposed hydroelectric power dam on the Vjosa River impacting the type locality - a large, shifting gravel, low altitude River - an atypical habitat for larvae of the I. tripartita group. For the first time we use molecular tools to delineate Isoperla species from the Balkans.
TL;DR: A remarkable new species of Isoperla Banks, 1906, IsoperLA chongxui sp.
Abstract: A remarkable new species of Isoperla Banks, 1906, Isoperla chongxui sp. nov. from Henan Province of China is described and illustrated. The new species is characterized by the conspicuous abdominal tergal processes in males. Comparisons are made between the new species and its congeners. New descriptions and illustrations are provided for Isoperla kozlovi Zhiltzova, 1972 from northeastern China. Isoperla fengi Wu & Claassen, 1934 and Isoperla curvispina (Wu, 1938) are considered nomen dubia due to lost types and poor original descriptions.