Three new freshwater species of the genus Achnanthidium (Bacillariophyta, Achnanthidiaceae) from Taiping Lake, China

Abstract

We describe three new Achnanthidium species, A. lacustre sp. nov., A. sublanceolatum sp. nov., and A. taipingensis sp. nov., from Taiping Lake, Anhui Province (China) based on light and scanning electron microscopy. A. lacustre sp. nov. belongs to the "A. minutissimum complex" of the genus, based on it having straight external distal raphe fissures and round to elliptical areolae. Both A. sublanceolatum sp. nov., and A. taipingensis sp. nov. belong to the "A. pyrenaicum complex" of the genus, based on them having transpically-elongated areolae and deflected external distal raphe fissures. All three species are sufficiently different from other similar species based on valve outline, shape of the axial and center areas, and striae density. These three new species are all observed in benthic collections from Taiping Lake.

Substratum‐associated microbiota

“…nov., and A. taipingensis P.Yu, Q.M.You et Kociolek sp. nov. from the benthos of Taiping Lake in the Anhui Province (Yu, You, Kociolek, & Wang, 2019), and A. mediolanceolatum P.Yu, Q.You et Kociolek sp. nov., A. parvulum Q.You, P.Yu et Kociolek sp.…”

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

“…The diatom genus Achnanthidium Kützing (1844) was originally described by Kützing, as a subgenus of the Achnanthes Bory de Saint-Vincent (1822). The species Achnanthes microcephalum Kützing was the type species of the subgenus (Pérès et al 2014;Yu et al 2019a). In the 1990s, Round et al (1990) resurrected Achnanthidium and elevated it to the genus level.…”

Five new Achnanthidiaceae species (Bacillariophyta) from Jiuzhai Valley, Sichuan Province, Southwestern China

“…Species belonging to Achnanthidium commonly, abundantly, and frequently occur in various freshwater habitats, such as streams, rivers, and lakes (Potapova & Ponader 2004, Kobayasi et al 2006, Pinseel et al 2015, Karthick et al 2017, Krahn et al 2018. Moreover, Achnanthidium species can occur across a broad range of freshwater habitats, from oligotrophic to eutrophic waters (Potapova & Hamilton 2007, Karthick et al 2017, Krahn et al 2018, Yu et al 2019. However, species recognition within the genus Achnanthidium has presented some challenges in terms of research.…”

“…To date, three complexes have been characterized in the Achnanthidium genus: (1) members of the A. minutissimum (Czarnecki 1994: 157) complex, have straight external distal raphe ends, and striae density that increase towards the apex; (2) members of the A. pyrenaicum (Kobayashi 1997: 148) complex, have external distal raphe ends that deflect or hook to one side of the valve; and (3) members of the A. exiguum (Czarnecki 1994: 157) complex, have external distal raphe ends curved in opposite directions (Round & Bukhtiyarova 1996, Krahn et al 2018, Pinseel et al 2015, Compère & Van de Vijver 2011, Jüttner et al 2011, Yu et al 2018, 2019. Currently, more than 200 Achnanthidium species have been reported in the literature worldwide (Marquardt et al 2017, Yu et al 2019. In China, roughly 60 Achnanthidium species have been reported (Liu et al 2013, Wang & Deng 2017, Yu et al 2017, but only a few have been reported as new species (Yu et al 2018, 2019, Liu et al 2016.…”

“…Currently, more than 200 Achnanthidium species have been reported in the literature worldwide (Marquardt et al 2017, Yu et al 2019. In China, roughly 60 Achnanthidium species have been reported (Liu et al 2013, Wang & Deng 2017, Yu et al 2017, but only a few have been reported as new species (Yu et al 2018, 2019, Liu et al 2016.…”