Paraboea myriantha Y.M. Shui & W.H. Chen, 2020

Shui, Yu-Min, Guo, Shi-Wei, Chen, Li & Chen, Wen-Hong, 2020, Two new species of Paraboea (Gesneriaceae) in Caryota obtusa forests in Southwest China, with compound and simple dichasia, respectively, PhytoKeys 157, pp. 207-216 : 207

Paraboea myriantha Y.M. Shui & W.H. Chen sp. nov. Figure 2

Type.

China. Yunnan Province: Hekou County, Nanxi Community, 22°38'18.44"N, 104°00'28.93"E, in the limestone forests, alt. 900 m, 26 August 2005, in flowers, Y.M. Shui et al. 44536 (holotype KUN).

Diagnosis.

The new species is similar to P. glutinosa (Hand.-Mazz.) K.Y.Pan in winged petioles, leaf-like bracts and compound dichasia, but distinguished by adaxial corolla lobes semicordate (vs. nearly rounded), tube obliquely campanulate (vs. urceolate) outside glandular-puberulent (vs. glabrous or rarely pubescent) and laterally uneven (vs. even), and glandular-puberulent filament (vs. covered by a beard of multicellular hairs); and similar to P. thorelii (Pellegr.) B.L.Burtt in winged petioles and compound dichasia, but distinguished by corolla tubes 9-10 mm long (vs. 3-4 mm long) outside glandular-puberulent (vs. glabrous) and staminodes 2 (vs. inconspicuous).

Description.

Herbs, up to 90 cm tall, stems 10-20 cm. Leaves opposite, clustered at stem apex; petiole 5-8 (-15) cm long and winged, wings (1-) 5-20 mm wide each side; leaf blade obovate, 12-30 (-48) × 5-13 (-16) cm, chartaceous, adaxially sparsely pubescent to glabrous, abaxially densely matted arachnoid, base cuneate to wing-like on petiole, margin repand-crenate and involute, apex mucronate to rounded; midrib depressed adaxially, protuberant abaxially; lateral veins 8-13 (-16) pairs, obscure adaxially and distinct abaxially. Dichasium terminal paniculate, with hundreds of flowers; peduncles up to 70 cm, densely arachnoid when young, sparsely puberulent to glabrous when mature; bracts (the lowermost fertile leaves) 2, leaf-like, ca. 7 × 3 cm, densely arachnoid abaxially; bracteoles 2, linear, ca. 2 × 0.5 mm; pedicels 5-8 mm long. Calyx 5-sect from base; segments linear, ca. 1 mm long, glabrous. Corolla purple adaxially and white abaxially (corollas purple when young), outside glandular-puberulent; tube obliquely campanulate, ca. 10 mm long, outside glandular-puberulent; adaxial lip 2-lobed, lobes semicordate ca. 3 × 6 mm; abaxial lip 3-lobed, lobes ca. 5 × 6 mm. Stamens 2, included; filaments lateral-fixed, ca. 8 mm long, glandular-puberulent from middle to top; anthers ca. 5 mm long; staminodes 2, 3-5 mm long. Pistil glabrous; ovary oblong, ca. 6 mm long; style linear, 4-5 mm long; stigma capitate. Capsule obviously twisted, 4.5-6.7 cm long, glabrous, with persistent calyx. Seeds ellipsoid, 0.6-0.7 × 0.15-0.2 mm.

Etymology.

The new species is named after its numerous flowers per an individual.

Distribution and habitat.

The new species only grows in Caryota obtusa forests of limestone areas in Hekou and Maguan counties of Yunnan, China (Figure 1 ).

Phenology.

Flowering from June to August; fruiting from July to November.

Additional specimens examined (paratype).

China. Yunnan Province: Hekou County, in dense forests on the limestone hillsides, alt. 700-950 m, 21 October 2001, Y.M. Shui et al. 15105 (KUN); at the same county, in the limestone seasonal forests, alt. 1000-1200 m, with fruits of last year, 28 March 2002, Y.M. Shui et al. 20595 (KUN); at the same county, in dense forests on limestone hillsides, alt. 1000 m, with young dichasia, 28 March 2002, Y.M. Shui et al. 20946 (KUN); at the same county, Nanxi Zhen, 22°40'8"N, 104°01'16"E, in forests, alt. 900 m. 6 September 2013, Y.M. Shui, B. Xiao, J. Wang et al. B2013-528 (KUN). Maguan County, Gulinqing Community, 22°43'N, 103°59'E, in the evergreen broad-leaved forests on limestone hillsides, alt. 1000 m altitude, 3 October 2002, Y.M. Shui et al. 30261 (KUN); at the same county, 3 October 2002, Y.M. Shui et al. s.n. (KUN); at the same county, in the limestone evergreen broad-leaved forests, alt. 794 m, 11 November 2006, Y.M. Shui et al. 16118 (KUN); at the same county, Jiahanqing Community, Moshizhai Village, 9 August 2018, Y.M. Shui et al. B2018-183 (KUN).

Note.

The new species appeared as Paraboea auriculata Y.M. Shui & W.H. Chen (nom. nud.) because of its winged petioles in Shui and Chen (2006). However, we decided to name it as Paraboea myriantha , after careful comparison of references and type specimens with similar species, P. glutinosa (Hand.-Mazz.) K.Y.Pan and P. thorelii (Pellegr.) B.L.Burtt. The new species is similar to the above two species on winged leaves and compound dichasia, but distinguished by corolla lobes (shape) and tubes (shape and indumenti) and glandular filament, which are described in diagnostics (Figure 2 ; Xu et al. 2008; Vu et al. 2011). Furthermore, P. glutinosa is distributed in South China, P. thorelii in South Laos (type locality) and North Vietnam, but the new species we proposed seems geographically distributed between the above two similar species. So, the future molecular work in the context of the whole genus may reveal if the above three species become a species complex with obvious geographical replacement.

Figures

Figure 1. The geographical distribution of Paraboea brevipedunculata W. H. Chen & Y. M. Shui, sp. nov. (square) and P. myriantha Y. M. Shui & W. H. Chen, sp. nov. (star).

Figure 2. Paraboea myriantha Y. M. Shui & W. H. Chen, sp. nov. (A, C-G, J) and its similar species P. glutinosa (B, H, I) A, B habitat C abaxial surface of leaf D flower bud E lateral view of flower F bird view of flower G, H front view of flower I lateral view of flower J flower and fruits (A and C photographed by Gui-Liang Zhang and all the others by Yu-Min Shui).