Insects are the most speciose group of animals, but the phylogenetic relationships of many major lineages remain unresolved. We inferred the phylogeny of insects from 1478 protein-coding genes. Phylogenomic analyses of nucleotide and amino acid sequences, with site-specific nucleotide or domain-specific amino acid substitution models, produced statistically robust and congruent results resolving previously controversial phylogenetic relations hips. We dated the origin of insects to the Early Ordovician [~479 million years ago (Ma)], of insect flight to the Early Devonian (~406 Ma), of major extant lineages to the Mississippian (~345 Ma), and the major diversification of holometabolous insects to the Early Cretaceous. Our phylogenomic study provides a comprehensive reliable scaffold for future comparative analyses of evolutionary innovations among insects.
Impacts of surface mining on ecosystems were investigated in the Guangdong Dabaoshan Mine region, southern China. Significant soil acidification has been induced by mining activities which cause oxidation of metal sulfides contained in the mine spoils. Natural colonization of vegetation in the mine site has been impeded and this has resulted in severe soil erosion. Acid mine drainage from this mine site has caused the degradation of the downstream aquatic ecosystems. Mine water with pH < 3Á5 has been continuously flowing into a first-order tributary of the Beijiang River and has destroyed all the aquatic life to a distance of at least 25 km downstream of the discharge point, even when the pH rose to above 6 in the Hengshishui River (a third-order tributary of the Beijiang River). Further downstream, macroinvertebrates first occurred at about 30 km from the discharge point, and only one species was found. This is in contrast to a reference site that was not affected by acid mine drainage, where 36 macroinvertebrate taxa were found. Acidic mine water also had marked impacts on the agricultural lands irrigated with it. Severe contamination of the soils by mine drainage is responsible for the extremely high concentrations of some heavy metals in the edible portions of a variety of food crops grown on the agricultural lands.
Five species of the genus Labiobaetis (Baetidae) are recognized from China based on mature nymphs, including a new species, Labiobaetis ancoralis n. sp. and a new combination, Labiobaetis mustus (Kang & Yang) n. comb. The new species differs from L. multus (Müller-Liebenau) and L. pulchellus (Müller-Liebenau & Hubbard) by the spatulate submarginal setae on labrum and the apical segment of maxillary palpus with a pronounced excavation near apex. Imago stage of L. mustus (Kang & Yang) n. comb. is described for the first time based on male and female imagoes reared from nymphs, which can be distinguished from other known imagoes of Labiobaetis by the color pattern of abdominal terga and hind wing having a tiny vestigial costal process. All Oriental species previously transferred to Pseudocloeon are reassigned to Labiobaetis in the present paper. An identification key is provided to the known mature nymphs of Oriental Labiobaetis species.
The paper provides a review of the subfamily Panchaetothripinae (Thysanoptera: Thripidae) in China, including descriptions of two new species: Helionothrips rugatus Mirab-balou and Tong new species and Panchaetothrips bifurcus Mirab-balou and Tong new species. Rhipiphorothrips concoloratus Zhang and Tong, originally described in Chinese, is re-described based on type specimens. Identification keys to 13 genera and 32 species of Chinese panchaetothripine are presented.
We sequenced the complete mitochondrial genome of Massicus raddei, which is the first beetle sequenced in Cerambycinae to date. The complete mitochondrial genome is 15,585 bp in length with an A + T content of 71.82%, and contains 13 protein-coding genes, 2 rRNAs, 22 tRNAs and a control region. The gene order and orientation are similar to that of typical insect species. These data will provide useful molecular information for phylogenetic relationships among the suborders of Coleoptera. By using 13 protein-coding genes as phylogenetic markers, the results support that the suborder Archostemata is a sister group to the remaining beetles and the most primitive suborder in any case; the suborder Myxophaga is sister to the suborder Adephaga.
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