Gaultheria albiflora (T.Z.Xu) P.W.Fritsch & Lu Lu, 2015

Fritsch, Peter W., Lu, Lu, Wang, Hong & Li, De-Zhu, 2015, New species, taxonomic renovations, and typifications in Gaultheria series Trichophyllae (Ericaceae), Phytotaxa 201 (1), pp. 1-26 : 2-5

1. Gaultheria albiflora (T.Z.Xu) P.W.Fritsch & Lu Lu , comb. et stat. nov.

≡ Chiogenes suborbicularis (W.W.Smith in Anonymous 1914: 186) Ching ex T.Z. Xu (1984: 40) var. albiflorus T.Z. Xu (1984: 41) . Type:— CHINA. Yunnan: Gongshan Xian, Mekong-Salwin divide, Sila, 4000 m, 16 August 1938, T.T. Yü 22351 (holotype KUN 0482916!, isotype E!, KUN 0482917!).

Prostrate shrublet with stems to 5 cm long from horizontal stolons, hermaphroditic. Current-year branchlets pale green, strongly flushed red above, to 1.8 cm long, not puberulent, with appressed to ascending or uncinate straight setae, longer setae 0.14–0.3 mm long. Internodes among largest leaves averaging ca. 1.0 mm long. Petioles 0.2–0.6 mm long, glabrous, margin entire. Longer leaf blades elliptic or ovate-elliptic, 2.5–5.2 × 1.5–2.8 mm, 1.5–2.4 times as long as wide, subcoriaceous, planar or often cupped, abaxially dull light green except glossy green or occasionally maroon near margin, glabrous, adaxially glossy green, glabrous, midvein abaxially raised, planar, or impressed, not thickened to slightly thickened immediately below apical gland, adaxially impressed, secondary veins abaxially obscure, adaxially obscure or faintly 1- to 3-veined; base cuneate to subrounded; margin serrulate except at very base, not thickened, planar, marginal teeth (setae) 4 to 9 per side, often incurved and lying atop or adjacent to upper leaf surface, or occasionally proximal or all teeth off surface, longer teeth 0.08–0.18 mm long; apex acute to obtuse, tip with planar gland. Overwintering flower bud pedicels 0.8–2.5 mm long, glabrous; overwintering flower buds subglobose, 1.4–1.9 × 1.3–1.6 mm, 1–1.4 times as long as wide, glabrous, bracteoles not keeled, margins eciliolate. Flowers 2.5–4.8 mm long. Calyx green or green flushed red proximally with lobes maroon or purple, paler toward apex, 1.5–3 mm long; lobes deltoid or ovate-deltoid, 1.2–1.8 × 1.3–2.2 mm, adaxially glabrous, smooth, apex obtuse, eciliolate, at least slightly erose. Corolla white, campanulate, 2.4–4.5 × 3–4.2 mm; lobes 0.8–1.6 × 1.4–1.9 mm. Stamens 10; filaments abruptly dilated at middle or gradually dilated to just below middle, 1–1.5 mm long; anther cells 0.4–0.5 mm long, awns 1 or 2 per theca, 0.12–0.3 mm long. Style 1–1.7 mm long; stigma deep pink. Fruiting pedicel 2.2–3.5 mm long. Fruiting calyx oblate, crateriform, widely open, 6–8 × 8–11 mm, outer wall sky blue, inner wall white or white flushed with pink; calyx lobes incurved, broadly deltoid, 2–3.5 mm long, apex eciliolate, not erose. Capsule green, exceeded by calyx lobes.

Illustrations — Figure 2 ; Fritsch et al. 2008: Fig. 13C–F.

Images — Figure 1D–F ; Fritsch et al. 2008: Fig. 14.

Phenology —Flowering July–August; fruiting August–September.

Habitat and distribution —Alpine meadows, in moss, humus, on rocks, near lakes; 3500–4200 m elev. Bhutan and China (Yunnan, Xizang) .

Discussion — Gaultheria albiflora was first described at the level of variety under Chiogenopsis suborbicularis , a species now recognized in Gaultheria [≡ Gaultheria suborbicularis W.W. Sm. in Anonymous (1914: 186)]. However, G. suborbicularis belongs to G. series Hispidulae Airy Shaw whereas it is clear to us that the variety belongs to G. series Trichophyllae on the basis of its 1-flowered inflorescences (versus several-flowered), 5-parted corolla (versus 4- parted), and blue fruiting calyx (versus red or white), among other characters differentiating the two sections. Because of a similar overall size and other characters, and because they often grow together, the identities of G. albiflora and G. eciliata (S.J.Rae & D.G.Long in Long 1988: 334) P.W.Fritsch & L.H.Zhou in Fritsch et al. (2008: 165) have been conflated and thus they have sometimes been collected together under the same collection number, including the type of G. eciliata (see below under the entry for that species). Under close inspection, G. albiflora can be distinguished from G. eciliata by the absence of leaf trichomes (versus one to several straight translucent trichomes on the petiole and adaxial leaf blade midvein proximally on at least some leaves), subglobose flower buds (versus laterally compressed), eciliate calyx lobe margins (versus ciliate), and larger fruiting calyces (6–8 × 8–11 mm versus 4.3–6 × 5–9 mm). Moreover, the leaf marginal setae of G. albiflora are generally more robust than those of G. eciliata , they are more often black than reddish brown (versus the opposite) and often mostly lie incurved on the upper leaf blade surface (versus usually off the surface proximally); and the calyx lobes of G. albiflora are ovate-deltoid, whereas those of G. eciliata are elongate-deltoid.

The E duplicates of T.T. Yü 19877 and 22292 are cited as paratypes of Gaultheria trichophylla var. eciliata S.J.Rae & D.G.Long in Long (1988: 334) but these plants are in fact G. albiflora , as are the other duplicates of these collections. The illustration of G. eciliata in Fritsch et al. 2008: Fig. 13 is a mixture of G. albiflora and G. eciliata . Gaultheria albiflora is illustrated in subfigures 13C–F (C and E are drawn from the duplicate of Yü 19877 at E), and F is drawn from the image of the living fruit in Fig. 14 of Fritsch et al. (2008; the caption erroneously states that 13F is based on the CAS specimen of Gaoligong Shan Biodiversity Survey 16874). Gaultheria eciliata in figures 13A–B in that work is drawn from the duplicate of Gaoligong Shan Biodiversity Survey 16874 at CAS. Figure 14 in Fritsch et al. (2008), showing a fruit image, is indicated as G. eciliata but is in fact G. albiflora .

Additional specimens examined — BHUTAN. Mongar: Pung La, 3660 m, 9 July 1949, F. Ludlow et al. 20904 p.p. (BM! mixed with the lectotype of G. eciliata , photograph of BM at E!).

CHINA. Yunnan: Deqin Xian. Yanmen Xiang, Biluo Xue Shan, E slope just below Sila Pass , 3936 m, 28°00 ʹ 8.5 ʺ N, 98°47 ʹ 54.8 ʺ E, 24 September 2013, L. Lu LL-2013-50 (CAS!, KUN!) ; Mekong-Salwin divide, Sila , 4200 m, T.T. Yü 22292 (A!, E!, KUN!) . Gongshan Dulongzu Nuzu Zizhixian. Bingzhongluo Xiang, vicinity of Niwaidanbu, ca. 2.4 direct km SW of Gawagapu Mtn., ca. 1.3 direct km E of Chukuai Lake, and ca. 16.5 direct km WSW of Bingzhongluo , W side of Gaoligong Shan , 3900 m, 27°59 ʹ 44.8 ʺ N, 98°27 ʹ 43.1 ʺ E, 30 August 2006, Gaoligong Shan Biodiversity Survey 31667 ( CAS!) ; Cikai Zheng, Yipsaka Lake, 2.4 direct km SE of Heipu Pass tunnel on new rd from Gongshan to Dulongjiang Valley , E side of Gaoligong Shan , 3500 m, 27°45 ʹ 14 ʺ N, 98°27 ʹ 33 ʺ E, 12 August 2006, Gaoligong Shan Biodiversity Survey 32019 p.p. (CAS! mixed with G. eciliata ) ; Upper Kiukiang Valley, ( Clulung ) S of Lungtsahmuru, 3900 m, 10 August 1938, T.T. Yü 19877 (A!, E!, KUN!) . Xizang: Chayu Xian. Ridong Community, Qimalazha to Xizha , 4300 m, 26 September 1982, Qinghai-Xizang Expedition 10719 ( KUN!) ; Chawalong , 17 July 2010, South Tibet Expedition STET-0719 (CAS!, KUN!) . Gongbujiangda Xian. Nambu La, Kongbo , 14,800 ft, 24 September 1947, F. Ludlow et al. 15775a ( BM!) . Motuo Xian. Duoxiongla, trail to Lage , 3700 m, 29°29 ʹ N, 94°55 ʹ E, 24 July 2007, L. Lu LL-07149A (CAS!, KUN!) .

Figures

FIGURE 1. Images of Gaultheria series Trichophyllae habitats, and G. albiflora, G. ciliisepala, and G. crassifolia. A–C. Gaultheria series Trichophyllae habitats: glacially carved valley along road from Gongshan to Dulongjiang, east slope of Gaoligong Shan, ca. 3400 m elev. (A), along trail from Qi Qi Forestry Station to Dong Shao Fang and the pass, east slope of Gaoligong Shan, ca. 3600 m elev. (B), just below Sila Pass, east slope of Biluo Xue Shan, ca. 4000 m elev. (C). D–F. Gaultheria albiflora, habit (D), fruit, lateral view (E) and apical view (F) (L. Lu LL-2013-50). G–K. Gaultheria ciliisepala, habit (G), flowers showing variation in size and color (H–I), fruit, lateral view (J) and apical view (K) (G: L. Lu & P.W. Fritsch LL-2011-8; H: L. Lu 06-15; I: L. Lu LL-2014-4; J–K: L. Lu LL-2013-20). L–P. Gaultheria crassifolia, habit (L), flower, lateral view (M) and apical view (N), fruit, lateral view (O) and apical view (P) (L, P: L. Lu LL-2013-13; M–N, LL-2014-30; O: L. Lu LL-2013-33). Photographs: A, C, E–F, I–L by PWF; B, D, G–H, M–P by LL. Scale bars: D, L, 5 cm; E–F, H–I, M–P, 5 mm; G, 10 cm; J–K, 10 mm.

FIGURE 2. Gaultheria albiflora. A. Fruiting plant. B. Leaf, adaxial view. C. Section of branchlet with leaf base in abaxial view and flower bud. D. Flower. E. Stamen. F. Nectar glands and gynoecium. G. Fruit, lateral view. H. Fruit, apical view. (A–C, G–H drawn from L. Lu LL-2013-50, CAS, and images of the living plant; D–F drawn from T.T. Yü 19877, E.)