A taxonomic study of Ooctonus (Hymenoptera, Mymaridae) from Heilongjiang, China.

Five species of Ooctonus Haliday (Hymenoptera, Mymaridae) from Heilongjiang Province, China, are reviewed. One species, Ooctonushuberi sp. n., is described as new, and four species, Ooctonusorientalis Doutt, Ooctonussaturn Triapitsyn, Ooctonussublaevis Förster and Ooctonusvulgatus Haliday are reported as new to China. A key to the females of the 10 described Chinese species is given. All the specimens are deposited in the insect collections of Northeast Forestry University, China.

[Macrobenthos community structure and its relationships with environmental factors in Weihe River basin, Northwest China].

In October 2011, an investigation was conducted on the macrobenthos at 45 sampling sites in the Weihe River basin of Northwest China. A total of 116 macrobenthos species were collected, of which, 91 species (78.4%) were aquatic insects, 12 species (10.3%) were mollusks, 9 species (7.8%) were annelids, and 4 species (3.4%) were crustaceans. According to the species composition and relative abundance of macrobenthos, the 45 sampling sites could be divided into three groups by using two-way indicator species analysis (TWINSPAN) and detrended correspondence analysis (DCA). In the first group, Serratella sp., Hydropsyche sp., and Antocha sp. were the indicator species. In the second group, Tabanus sp., Alotanypus venustus, one species of Pelecorhynchidae, Liodessus sp., and Limnodrilus hoffmeistteri were the indicator species. In the third group, Ephemera nigroptera and Polypylis hemisphaerula were the indicator species. The canonical correspondence analysis (CCA) indicated that 'cobble + boulder' type substrate, current velocity, water conductivity, water depth, and water total nitrogen content had significant effects on the spatial distribution of macrobenthos in Weihe River basin.