Morphology and ultrastructure of Hippodonta qinghainensis sp. nov. (Bacillariophyceae), a new diatom from Lake Qinghai, China

Abstract

A new medium-sized species of Hippodonta (Bacillariophyceae) is described from Lake Qinghai, China. The morphology and ultrastructure of Hippodonta qinghainensis sp. nov. are described using light and scanning electron microscopy. This new species is compared with similar species of Hippodonta using conventional and geometric morphometric analyses. Hippodonta qinghainensis can be separated from the other species of Hippodonta by a unique combination of characters that include an elliptic-lanceolate to rhombic-lanceolate valve shape, non protracted apices, the absence of fascia, relatively coarse, uniseriate striae and the presence of two rows of lineolae around the valves apices.

Ultrastructure of three Species of Entomoneis (Bacillariophyta) from Lake Qinghai of China, with reference to the external areola occlusions

“…These studies have provided a list of taxa, but lack useful illustrations (drawings or micrographs) for the taxa observed. However, some interesting new species recently published have been well documented ( Peng et al 2014 ; 2016 ; Liu et al 2020 ; Deng et al 2021 ), confirming that endemic diatom species inhabit this ancient lake. This paper provides further evidence of endemic taxa with the description of two new species of Entomoneis .…”

“…The surface water evaporating is nearly the sole path for loss of lake water. The lake has an 18.3 m average water depth and maximum of 26.6 m; the average values for alkalinity and pH are 25.6 mmol l ·1 and 9.2 respectively ( Peng et al 2014 ). There is a three-month ice-covered period (middle November to middle February) in Lake Qinghai so that the growth period for diatoms is mainly from May to October.…”

Diatoma sinensis: a new diatom species (Bacillariophyta) found in the brackish Lake Qinghai, China

“…Later, Peng et al (2013) and Peng (2014) studied diatom assemblages deposited in sediment traps deployed in the center of the lake. From this work, a new species Hippodonta qinghainensis Peng & Rioual ( Peng et al 2014 ), and a new variety, Gyrosigma peisonis var. major Peng, Rioual & Sterrenburg ( Peng et al 2016 ) were described.…”

“…Surface water evaporation is almost the sole source of water loss from the lake. The lake has an 18.3 m average water depth, and the maximum is 26.6 m. The average values for alkalinity and pH are 25.6 mmol L -1 and 9.2 respectively ( Peng et al 2014 ). There is a three-month ice-covered period (middle November to middle February) in Lake Qinghai so the growth period for diatoms is mainly from May to October.…”

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

“…More recently, descriptions of endemic species from freshwater environments of China have grown dramatically (e.g. Li et al ; Liu et al , , ; You et al , ; Peng et al ; ; among many others), and genera that are found only in the region (e.g. Oricymba Zhang et al ) or as disjuncts with other regions ( Gomphosinica Kociolek et al ) have also been detailed.…”