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Issue: Vol. 770 No. 4: 25 Aug. 2026
Type: Article
Published: 2026-08-25
DOI: 10.11646/phytotaxa.770.4.3
Page range: 261-270
Abstract views: 17
PDF downloaded: 0

Morphological study of Mallomonas gemina (Synurales, Chrysophyceae) and description of Mallomonas geminiformis sp. nov.

Severtsov Institute of Ecology and Evolution; Russian Academy of Sciences; Leninsky Prospect 33; 119071 Moscow; Russia
Institute for Cellular and Intracellular Symbiosis; Orenburg Federal Research Center; Ural Branch; Russian Academy of Sciences; Pionerskaya Street; 11; 460000; Orenburg; Russia
Joint Vietnam-Russia Tropical Science and Technology Research Center; 63 Nguyen Van Huyen; Nghia Do; Cau Giay; Ha Noi; 11307; Vietnam
Algae Mallomonas section Torquatae scale ultrastructure new species tropics

Abstract

A morphological study of Mallomonas gemina was conducted based on material from Vietnam. The ultrastructure of the scales and bristles was examined using transmission and scanning electron microscopy. A detailed comparison with illustrations of M. favosa f. gemina from the type locality in Malaysia revealed a number of important morphological features that supplement the description of this taxon. The morphotype previously reported from Vietnam as M. gemina differs in several ultrastructural characters and represents a species new to science. Its distinguishing features include larger rounded pits and a fewer number of pits along the posterior submarginal rib. The paper provides a description of M. geminiformis sp. nov.

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How to Cite

Gusev, E.S., Ignatenko, M.E. & Tran, H. (2026) Morphological study of Mallomonas gemina (Synurales, Chrysophyceae) and description of Mallomonas geminiformis sp. nov.. Phytotaxa 770 (4): 261–270. https://doi.org/10.11646/phytotaxa.770.4.3