Two new freshwater species of the genus Achnanthidium (Bacillariophyta, Achnanthidiaceae) from Qingxi River, China

By

Yu, Pan
You, Qingmin
Pang, Wanting
Wang, Quan-Xi

Type

Article

Date of Publication

2022-3-4

Original Publication

PhytoKeys

Volume

192

Pages

11--28

Subjects

Diatoms , monoraphid , Morphology , new species , taxonomy

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers [2010]-

Identifiers

DOI: https://doi.org/10.3897/phytokeys.191.78489

 

Abstract

We describe two new Achnanthidium species, A. anhuensesp. nov. and A. qingxiensesp. nov., from Qingxi River, Anhui Province, China, based on light and scanning electron microscopy. Both species belong to the “A. pyrenaicum complex” of the Achnanthidium genus, based on their possession of transapically-elongated areolae and deflected external distal raphe fissures. A. anhuensesp. nov. has a slightly irregular linear-lanceolate valve with rounded or weakly protracted apices and a transapically rectangular or bow tie central area on the raphe valve. A. qingxiensesp. nov. has a linear-lanceolate valve with rounded apices and the axial area distinct expanded apices on the rapheless valve. Both species differ sufficiently from other similar species, based on valve outline, shape of the axial and central areas and striae density. These new species were all collected from stone substratum.