Description of two new species of the genus Glyphiulus Gervais, 1847 (Diplopoda: Spirostreptida: Cambalopsidae) from southern China.

Two new species of the millipede genus Glyphiulus Gervais, 1847 are described from southern China: Glyphiulus fortis sp. nov. and Glyphiulus hainanensis sp. nov. Glyphiulus fortis sp. nov. is cavernicolous, vs. G. hainanensis sp. nov. which was collected from an epigean environment. Both of them belong to the G. javanicus-group. Additionally, DNA barcoding and phylogenetic analyses based on nucleotide sequences of COI and 16S of the two new species, as well as their allied species were conducted. The morphological characteristics, the genetic distances and the phylogenetic tree revealed that the two new species are unambiguously distinct from their congeners.

Description of Hypocambala zizhongi sp. nov. and the new combination, Glyphiulus polytrichus (Golovatch et al., 2011) comb. nov., based on morphological and molecular data (Spirostreptida: Cambalidea: Cambalopsidae).

The recent delimitation of the cambalopsid genera Hypocambala and Glyphiulus is debatable. The focus of controversy is whether the presence of crests on the trunk rings is an appropriate key character dividing these two genera. To address this issue, we conducted a molecular phylogenetic analysis including species with or without crests belonging to Hypocambala and species with crests belonging to Glyphiulus. The results of the phylogenetic analysis suggest that cambalopsids with crests are monophyletic and sister to a species without crests. Hypocambala polytricha, a cambalopsid with crests that is in a clade with crested Glyphiulus species, should be transferred to Glyphiulus. Therefore, a new combination is proposed, Glyphiulus polytrichus comb. nov. In addition, a discussion on the boundary between these two genera and a description of a new species, Hypocambala zizhongi sp. nov., are provided.

First description of the male of Glyphiulus formosus (Pocock, 1895) (Diplopoda: Spirostreptida: Cambalopsidae) from China.

The male of Glyphiulus formosus (Pocock, 1895) is described for the first time based on specimens collected from Shenzhen, Guangdong, China. According to the male sexual characters, this species is verified to be a member of the G. javanicus group. In addition, a DNA barcode of the partial COI gene of G. formosus is provided.

[Dianchi Lake macroinvertebrate community succession trends and retrogressive analysis].

Historical records and data from yield surveys conducted in 2009 and 2010 were used to investigate macroinvertebrate community succession trends in Dianchi Lake. Species richness has declined from 57 in the 1980s to 32 in 2010, representing a species loss of 44%. Among the major benthic groups, the highest rate of loss was recorded for mollusks (75%) and aquatic insects (39%). Surveys in 2009 and 2010 across the lake revealed that the total density was 1776 ind/m2, comprising oligochaetes (1706 ind/m2) and chironomids (68 ind/m2). Over a nearly twenty-year span (1992-2010), the density and biomass of oligochaetes first increased sharply (1992-2002) and then declined gradually (2002-2010). Further, chironomids have decreased gradually while the proportion of abundant species has increased. Limnodrilus hoffmeisteri became the sole dominant species with an average relative abundance of 74.1%. Cosmopolitan species, such as Einfeldia sp., disappeared across the lake; instead, tolerant species such as Chironomus plumosus, Ch. attenuatus and Tanypus chinensis became the common. Mollusk community structure has become simpler and many native species have gone extinct. Species of concern include Margarya melanioides, M. mondi, M. mansugi and Cipangopaludina dianchiensis, all rated as critically endangered by the IUCN. We found that the Shannon-Wiener index declined in Dianchi Lake, particularly in Caohai Lake, from 2.70 in the 1950s to 0.30 in 2009 and 2010. Species richness and biodiversity was significantly negative correlated with total phosphorus and total nitrogen. Factors responsible for the benthic community retrogression described here include habitat destruction, lowering of water quality, outbreaks of blue-green algae, extinction of submerged plants and lack of germplasm resources.