Saturday, April 27, 2024

[Botany • 2024] Sanjappa vietnamica (Fabaceae: Caesalpinioideae) • Studies of Asian ‘Calliandra' lead to expansion of Sanjappa


Sanjappa vietnamica  Thulin,

in Thulin, 2024.
photographs by Djaja D. Soejarto.
 
Abstract
The genus Sanjappa, previously with the single species S. cynometroides in southern India, is expanded to include S. umbrosa, comb. nov., in northeastern India, Bangladesh, Myanmar and China (Yunnan) and S. vietnamica, sp. nov., in southern Vietnam. Sanjappa differs from Thailentadopsis, its sister genus in the Zapoteca clade, by having leaves with extrafloral nectaries in the form of sessile (versus stipitate) glands and elastically dehiscent, not moniliform pods (versus pods not elastically dehiscent and submoniliform). Sanjappa umbrosa and S. vietnamica differ from S. cynometroides by having bipinnate leaves with one pair of pinnae (versus simply pinnate leaves with two leaflets only) and a four-lobed (versus three-lobed) corolla. In S. umbrosa each pinna is 2–3-foliolate and paired stipular spines are mainly present on younger growth, whereas in S. vietnamica each pinna is (3–)4–5-foliolate and branches, including major ones, are armed with numerous paired spines with thickened bases. Synonymies, images and notes on distribution, habitat, taxonomy and conservation for the three species of Sanjappa are provided, and all names are typified. With the taxonomic changes proposed here, all Asian species previously treated as members of Calliandra have been accommodated outside this genus.

Keywords: lectotypification, taxonomy, Thailentadopsis, Zapoteca clade


Sanjappa E.R.Souza and Krishnaraj (Souza et al. 2016)
Type: Sanjappa cynometroides (Bedd.) E.R.Souza and Krishnaraj.

Sanjappa cynometroides (Bedd.) E.R.Souza and Krishnaraj (Souza et al. 2016) 

Sanjappa umbrosa (Wall.) Thulin, comb. nov.  


Sanjappa vietnamica sp. nov. from the type locality in Nui Chua National Park, Ninh Thuan Prov., Vietnam. (A) tree, showing major branches armed with numerous paired spines with thickened bases, (B) spiny branches showing paired stipular spines, (C) branchlet showing inflorescences and bipinnate leaves.
photographs by Djaja D. Soejarto.

Sanjappa vietnamica Thulin, sp. nov.  

A species with bipinnate leaves with one pair of pinnae as in Sanjappa umbrosa (Wall.) Thulin, but differing by having each pinna with (3–)4–5 (versus 2–3) leaflets and by having major branches armed with paired spines with thickened bases (versus spines mainly on younger growth).


Mats Thulin. 2024. Studies of Asian ‘Calliandra' lead to expansion of Sanjappa (Fabaceae-Caesalpinioideae). Nordic Journal of Botany. DOI: 10.1111/njb.04241