Wednesday, May 29, 2019

[Botany • 2019] Fordiophyton jinpingense (Sonerileae, Melastomataceae) • A New Species of Fordiophyton from Yunnan, China


Fordiophyton jinpingense J.H.Dai & Z.Y.Yu

in Dai, Zhou, Yu, et al., 2019. 

Abstract
Fordiophyton jinpingense (Melastomataceae; Sonerileae), a species occurring in south-eastern Yunnan, China, is described as new, based on morphological and molecular data. Phylogenetic analyses, based on nrITS sequence data, showed that, except F. breviscapum, all species sampled in Fordiophyton formed a strongly supported clade in which two geographical lineages were recovered. The generic placement of F. jinpingense is well supported by phylogenetic analyses and a character combination of 4-merous flowers, distinctly dimorphic stamens and the connectives basally not calcarate. Molecular divergence and morphological evidence indicate that F. jinpingense is well separated from other members of the genus, thus justifying its recognition as a distinct species. Fordiophyton jinpingense is phylogenetically closest to F. repens, but differs markedly from the latter in stem morphology (short, obtusely 4-sided vs. long, 4-angular), habit (erect vs. creeping), leaf size (6–16.5 × 4.5–13 cm vs. 4–7.5 × 4–6.5 cm) and flower number per inflorescence (5–13 vs. 3–6).

Keywords: Fordiophyton, Melastomataceae, taxonomy, phylogeny




 Figure 3. Detail of inflorescence, flower, stamens, ovary and fruit of Fordiophyton jinpingense, all from Y. Liu 728 (SYS, A).
A Mature inflorescence B side view of a flower C top view of a flower D longitudinal section of a flower showing dimorphic stamens and ovary crown E anther morphology in detail F transection of ovary at young fruit stage, showing the very short-stalked, nearly sessile placenta G young fruit showing the crown not exserted from hypanthium. Scale bars: 5 mm (D–F).

Figure 2. Fordiophyton jinpingense, all from Y. Liu 728 (SYS, A).
A Habitat B a flowering individual C adaxial leaf surface D abaxial leaf surface E petiole villous with multiseriate hairs F young inflorescence G young inflorescence dissected showing the position and morphology of bracts. Scale bar: 2 cm (G).

 Holotype of Fordiophyton jinpingenseY. Liu 728 (A) collected from Ma-an-di, Jinping County, Yunnan, China.

Fordiophyton jinpingense J.H.Dai & Z.Y.Yu, sp. nov.
Type: CHINA. Yunnan: Jinping County, Ma-an-di town, 900–1900 m alt., damp but well drained places in forest, 10 Mar 2019, Ying Liu 728 (holotype: A; isotype: SYS).

Diagnosis: Differs from Fordiophyton repens in having slightly obtusely 4-sided short stem (vs. 4-angular, long and creeping), mature leaves 6–16.5 × 4.5–13 cm (vs. 4–7.5 × 4–6.5 cm) sparsely and shallowly dentate leaf margin with each tooth having a caducous terminal seta (vs. densely denticulate, persistent) and inflorescence 5–13-flowered (vs. 3–6-flowered).


Etymology: The specific epithet is derived from Jinping County, the type locality of Fordiophyton jinpingense.

Distribution: Fordiophyton jinpingense is currently known only from Jinping County, south-eastern Yunnan, China (Fig. 7). It occurs in dense or open forests, often in damp, shaded, but well drained places, such as on steep slopes, at 900–1900 m alt.


 Jin-Hong Dai, Qiu-Jie Zhou, Zhi-Yong Yu, Ren-Chao Zhou and Ying Liu. 2019. A New Species of Fordiophyton (Sonerileae, Melastomataceae) from Yunnan, China. PhytoKeys. 122: 15-28. DOI: 10.3897/phytokeys.122.35260