Saturday, September 17, 2022

[Botany • 2022] Myanmaranthus roseiflorus (Marantaceae) • A New Genus and Species from northern Myanmar

  

Myanmaranthus roseiflorus  Nob.Tanaka, Suksathan & K.Armstr.,

in Tanaka, Ohi-Toma, Suksathan, Aung, ... et Armstrong, 2022. 

Myanmaranthus Nob.Tanaka, Suksathan & K.Armstr., a new genus of Marantaceae from northern Myanmar, is described with a single species, M. roseiflorus Nob.Tanaka & K.Armstr. Its relationship to all other genera in Asian Marantaceae is investigated through morphological examination and molecular phylogenetic analyses based upon chloroplast (rps16 intron, trnLtrnF) and nuclear (ITS and ETS) sequences. Myanmaranthus differs morphologically from the most closely related genus, Phrynium Willd., in having a combination of the following characters: a rosulate habit, a loose paniculate inflorescence arising from the rhizome, the absence of interphylls and bracteoles, and fertile bracts each holding a single pink flower. Thus far, this new taxon is known only from the type locality in Kachin State, Myanmar. A key to the genera of Asian Marantaceae is provided. 

Key words: Burma, Donax clade, Hkakaborazi National Park, Kachin, Myanmar, new taxon, Zingiberales.

 Floral part of Myanmaranthus roseiflorus.
A. Flower. B. Bract. C. Bicarinate prophyll. D. Sepal. E. One of three corolla lobes; this lobe differs from the other two and is connate to the callose staminode. F. One of two equal corolla lobes. G. One of two equal outer petaloid staminodes. H. Callose staminode. I. Side view of cucullate staminode and style. J. Stamen with spatulate appendage. K. Young fruit.
Scale bars: 1 mm (D, K), 2 mm (J-I), 5 mm (A, E-H) and 1 cm (B-C). 
Drawn by Kaoru Yoneda.

 Myanmaranthus roseiflorus.
A. Inflorescence. B. A single leaf. C. Side view of flower enlarged. D. Ovary after flowering. Cross section of a young fruit (inset).
Scales: 3 mm (D), 1 cm (C), 5 cm (A), and 10 cm (B).

Myanmaranthus Nob.Tanaka, Suksathan& K.Armstr., gen. nov. 

Myanmaranthus roseiflorus Nob.Tanaka& K.Armstr., sp. nov.
 
Etymology: The generic name Myanmaranthus” is derived from Myanmar, the country in which this new genus was discovered. The specific epithet “roseiflorus” refers to the pink color of the flowers


Nobuyuki Tanaka, Tetsuo Ohi-Toma, Piyakaset Suksathan, Mu Mu Aung, Axel Dalberg Poulsen, Salasiah Mohamad and Kate E. Armstrong. 2022. Myanmaranthus roseiflorus, A New Genus and Species of Marantaceae from Myanmar. Journal of Japanese Botany. 97(4):187-196. 
http://www.jjbotany.com/pdf/JJB97-4_187-196_abstract.pdf