Quanxi Wang

New Gomphonema Ehrenberg (Bacillariophyceae: Gomphonemataceae) species from Xinjiang Province, China

Five new species of the diatom genus Gomphonema are described from high-elevation localities in Xinjiang Province, China. Morphological features of these new taxa are described based on light and scanning electron microscopy. Most of the new species are morphologically similar to other ‘typical’ members of the genus, sharing C-shaped areolae formed by external flaps or occlusions. Gomphonema intricatioides sp. nov. differs from the other species by having internal areolar occlusions. This study follows others describing new species of Gomphoneis from the same region. Xinjiang Province is home to many new species, especially in higher elevation localities that are isolated from other regions. These more remote locations may be insulated from the impacts of human disturbance, and thus harbour more endemic species.

New freshwater diatom genus, Theriotia gen. nov. of the Stephanodiscaceae (Bacillariophyta) from south‐central China

We describe a new genus and species of the diatom family Stephanodiscaceae with light and scanning electron microscopy from Libo Small Hole, Libo County, Guizhou Province, China. Edtheriotia guizhoiana gen. & sp. nov. has striae across the valve face of varying lengths, and are composed of fine striae towards the margin and onto the mantle. Many round to stellate siliceous nodules cover the exterior of the valve. External fultoportulae opening are short tubes; the opening of the rimportula lacks a tube. Internally a hyaline rim is positioned near the margin. Marginal fultoportulae possess two arcuate opercles. Areolae have domed cribra on the valve face. Those near the margin do not open to the interior. One to three sessile to slightly‐raised rimportulae are placed on the valve face towards the margin; they do not terminate shortened striae towards the center of the valve. This suite of features distinguishes this group from other known genera in the Stephanodicaeae. Cyclotella shanxiensis is transferred to Edtheriotia, making the new combination E. shanxiensis (Xie & Qi) Kociolek et al. comb. nov. It differs from E. guizhoiana by the presence of open pores near the margin of the valve. Features of the new genus are compared and contrasted with others in the Family Stephanodiscaceae. The two species of the genus, unlike most in the family, are known only from rivers and ponds from China and Japan.

A new species of Simonsenia from a karst landform, Maolan Nature Reserve, Guizhou Province, China

A new species, Simonsenia maolaniana sp. nov., is reported from a typical karst landform, Maolan Nature Reserve, Guizhou Province, China. The valves are lanceolate (larger frustules) to elliptical-lanceolate (smaller frustules), widest in the centre of the valve, and narrowly rostrate, not protracted at the ends. The more lanceolate valve outline, greater valve width and coarser structure distinguish S. maolaniana from other Simonsenia species. A direct comparison between the new species and the sympatric (though rare) S. delognei was possible because the two occurred together at Maolan. This is the first report of Simonsenia from continental China.