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Issue: Vol. 720 No. 3: 2 Oct. 2025
Type: Article
Published: 2025-10-02
DOI: 10.11646/phytotaxa.720.3.8
Page range: 281-288
Abstract views: 268
PDF downloaded: 6

Mallomonas cetosa sp. nov. (Synurales, Chrysophyceae)—a new species from the tropics

Institute of Biology, Komi Scientific Center, Ural Branch, Russian Academy of Sciences, Kommunisticheskaya Street, 28, 167982, Syktyvkar, Russia
Institute for Cellular and Intracellular Symbiosis, Orenburg Federal Research Center, Ural Branch, Russian Academy of Sciences, Pionerskaya Street, 11, 460000, Orenburg, Russia
Coastal Branch of Joint Viet Nam-Russia Tropical Science and Technology Research Center, 30 Nguyen Thien Thuat, Nha Trang 650000, Vietnam
Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Leninsky Prospect 33, Moscow, 119071, Russia
Synurales Mallomonas section Torquatae scale ultrastructure new species Algae

Abstract

Mallomonas cetosa sp. nov. is described from Vietnam based on silica-scale morphology studied by transmission and scanning electron microscopy. The new species is distinguished by the presence of transverse ribs on the posterior flange, an expansion of the basal plate behind the distal part of the dome on collar scales, a “window” with numerous rimmed pores at the angle of the posterior submarginal rib, and polygonal to rounded mesh of the inner reticulation of the secondary siliceous layer. Based on the ultrastructure of the scales, the new species should be assigned to the section Torquatae.

The distribution and habitat conditions of the new species were summarised. Mallomonas cetosa sp. nov. was found in 33 localities in 10 provinces in Vietnam.

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How to Cite

Sterlyagova, I.N., Ignatenko, M.E., Lan, N.T. & Gusev, E.S. (2025) Mallomonas cetosa sp. nov. (Synurales, Chrysophyceae)—a new species from the tropics. Phytotaxa 720 (3): 281–288. https://doi.org/10.11646/phytotaxa.720.3.8