NEWS - A new species, Shun river diatom (Ulnaria shun-biseriata), was discovered in Hunan Province, southern China, described based on light and scanning electron microscopy observations with the characteristics of lanceolate valve lines, apical valve crests, slightly wavy valve margins, mostly biseriate striae, variable central areas, and closed valvocopules.
The specific epithet shun-biseriata is a combination of the Shun River and the adjective biseriate to reflect the type locality and the character of the mostly biseriate striae. The new species is only known from the type locality with a relative abundance of about 1%. Samples were scraped from rock surfaces collected in the Shun River.
This benthic epilithic species is related to Gyrosigma kuetzingii (Grunow) Cleve, Encyonema appalachianum Potapova, Pinnularia subgibba Krammer, P. borealis Ehrenberg, Gomphonema berggrenii Cleve, Epithemia spp., Nitzschia spp., Iconella spp., and others. Environmental parameters with conductivity = 70.1 ± 0.1 μS cm-1; pH = 8.5 ± 0.1 and water temperature = 24.5 ± 0.1C.
U. shun-biseriata is most similar to U. oxybiseriata D.M. Williams & Bing Liu because both species have overlapping valve dimension ranges and are characterized by apical apices and biseriate striae. However, U. shun-biseriata has wider valves and wavy valve margins (vs. straight or non-wavy valve margins, linear lanceolate valves and lines).
Original research
Zheng Y, Liu B, Rioual P, Long J-Y, Zhou M (2024). Ulnaria shun-biseriata sp. nov. (Bacillariophyta) from the Shun River in Hunan Province, China. PhytoKeys 246: 315-327, DOI:10.3897/phytokeys.246.130942
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