A new species of Bienertia (Chenopodiaceae) from Iranian salt deserts: A third species of the genus and discovery of a fourth terrestrial C₄ plant without Kranz anatomy

Abstract

Bienertia is a very interesting genus with its unique C₄ photosynthesis in a single cell. Recent investigations on the taxonomy of the genus using a multidisciplinary approach revealed the existence a third species of this genus from the margin of Dasht-e Kavir (desert plain) in central Iran, thus adding a fourth terrestrial C₄ plant lacking Kranz anatomy. The flattened leaves, the semi-inferior ovary resulting from adnation of the perianth with the ovary, in addition to cotyledon morphology and hypocotyl length, provide evidence for the existence of a new species. The new species is here described as Bienertia kavirense Akhani spec. nov., after its locality at the margin of the Kavir. The gametic chromosome complement of the new species is n = 9. The carbon isotope values (δ¹³C) showed a C₄ photosynthesis which is remarkably less negative than in the two other species of Bienertia. Detailed information on the morphology, leaf anatomy, and ecology of the new species is provided, and the new association “Bienertio kavirense–Cornulacetum aucheri” is described as a unique plant community occurring at the margin of the Dasht-e Kavir. Only a few species, such as Salsola annua (Bunge) Akhani comb. nov., associate with B. kavirense.

Keywords:

• Halophytes
• δ ¹³ C value
• C₄ photosynthetic pathway
• SW Asian flora
• endemism
• cytology

Acknowledgments

This paper is the result of the research projects “Geobotanical studies in different parts of Iran, IV” partly supported by the Research Council of the University of Tehran and project number 842951 supported by the Iran National Science Foundation. We gratefully acknowledge Dr. T. Sage (Toronto) for her help in anatomical work, the linguistic improvement of the text and providing the carbon isotope analysis by Prof. G. Edwards (Pullman), checking of the Latin diagnosis by Prof. F. Khassanov (Tashkent), and two anonymous reviewers for improving an earlier version of this manuscript.

Additional information

Notes on contributors

H. Akhani

Present address: Department of Biology, Faculty of Science, University of Zabol, Zabol, Iran