Nertera taiwaniana Masam., Trans. Nat. Hist. Soc. Form. 28: 144. 1938.

Chen, Wei-Chih, Wang, Chih-Chiang & Chang, Kun-Cheng, 2021, Re-appraisal of Nertera (Rubiaceae) in Taiwan, PhytoKeys 182, pp. 83-91 : 83

Nertera taiwaniana Masam., Trans. Nat. Hist. Soc. Form. 28: 144. 1938.

Figs 1b, d, f, h , 3

Nertera granadensis auct. non Druce; Liu & Yang, Fl. Taiwan 2nd 4: 306. pro parte; Chen & Taylor, Fl. China 19: 257. 2011. syn. N. taiwaniana .

Nertera depressa auct. non Banks & Sol. ex Gaertn: Yamamoto, Journ. Soc. Trop. Agr. 10: 276. 1938, 12: 24. 1940; Chao, Fl. Taiwan 4: 315. pro parte; Ko, Fl. Reipubl. Popularis Sin. 71 (2): 164. syn. N. taiwaniana .

Notes.

Creeping herbs; branches slender, 5-15 cm long, glabrous. Leaves opposite, deltoid to ovate, membranous to papery, 4-12 mm long, 2-8 mm wide, apex acute to acuminate, base cordate or truncate, margins entire, more or less undulate; petioles 1.5-6 mm long; secondary veins 2-3 on each side of mid-vein, distinctly convex on upper surface, not apparent on lower surface; stipules triangular, membranous, ca. 1.5 mm long and 1.5 mm wide. Flowers sessile, solitary, terminal, ca. 2 mm long and 1.8 mm wide; calyx truncate, glabrous; corolla yellowish-green, lobes 4, deltoid to ovate, ca. 0.7 mm long and 0.6 mm wide, apex acute; stamens 4, anthers oblong, ca. 0.29 mm long and 0.15 mm in diameter, filaments ca. 0.5 mm long; ovary ellipsoid, two-celled, each with one ovule; two styles, free, ca. 1 mm long. Fruit globose drupe, 4.5-6.5 mm in diameter, red with black spots at maturity; seeds 2, yellowish-white, long-ovate to spathulate, 2.5-3.5 mm long, 1.5-2 mm wide, surfaces smooth.

Distribution and habitat.

Nertera taiwaniana is endemic in Taiwan. Growing on hillsides at medium altitudes in the eastern and southern parts of the Island.

Specimens examined.

Taiwan, Pingtung: Chunjih Hsiang, 30 Dec 1999, C. I Peng 17902 (HAST); Tahan Forest Road, 26 Jul 2001, Y. Y. Huang 554 (HAST); Chinshuiying, 23 Jun 1999, K. F. Chung 1348 (HAST); 18 May 2008, K. C. Chang & C. C. Wang 4447 (TCF); 6 Jun 2009, K. C. Chang & C. C. Wang s. n. (TCF) ; Ilan: Shenmihu, 28 Dec 1987, Y. M. Hsu 554 (TAI); Chialohu, 10 May 2002, C. I Huang 815 (HAST); Mt. Taiping, 22 Dec. 1995, C. H. Chen 1519 (HAST); Mt. Fanpao , 17 Apr 1996, C. C. Liao 1798 (HAST) ; Taitung: Mt. Sung, 30 Aug 1932, S. Suzuki s. n. (TAI); 13 May 1988, S. Y. Lu 22900 (TAIF); Mt. Kutzulun , 20 Jul 1937, H. Simizu 3888 ( Nertera taiwaniana , holotype: TAI!) .

Excluded species to the Flora of Taiwan

Figures

Figure 1. Photographs of Nertera nigricarpa Hayata and N. taiwaniana Masam A flower of N. nigricarpa. B flower of N. taiwaniana C fruits and leaf shape of N. nigricarpa D fruits and leaf shape of N. taiwaniana E top side of N. nigricarpa seed F top side of N. taiwaniana seed G underside of N. nigricarpa seed H underside of N. taiwaniana seed. Scale bars: 2 mm.

Figure 3. Nertera taiwaniana Masam A habit B leaf C stipule D inflorescence E flower F fruit and G seeds.