Gyrocheilos taishanense G.T. Wang, Yu Q. Chen & R.J. Wang, 2021

Wang, Gang-Tao, Liu, Fang-Pu, Jiang, Guo-Bin, Zhang, Ying, Chen, Yu-Qiang & Wang, Rui-Jiang, 2021, Gyrocheilos taishanense: A new species of Gesneriaceae from Guangdong, China, Phytotaxa 478 (2), pp. 216-224 : 219-222

Gyrocheilos taishanense G.T. Wang, Yu Q. Chen & R.J. Wang , sp. nov. ( Fig. 2 ).

Type: — CHINA. Guangdong: Jiangmen City, Taishan , 21°55’26”N, 112°56’22”E, elev. ca. 560 m, 1 May 2018, flowering, Gang-Tao Wang et al. 669 (holotype IBSC 0855721 ; isotypes IBSC0855722 , KUN1347954 , PE02331416 ) .

Gyrocheilos taishanense is morphologically similar to G. microtrichum W.T. Wang (1981: 32) , but is distinguished by its glabrous or sparsely hairy pedicels (vs. glabrous in G. microtrichum ), zygomorphic (vs. actinomorphic) calyx with hairs in unequal (vs. equal) length, and slightly bilobed (vs. entire) adaxial corolla lips ( Table 2).

Rosulate herb, rosulate, rhizomatous. Petioles 4.5–13.7 cm long, with 0.2–0.5 mm long hispid hairs. Leaf blade 7.5– 13.1 × 8.5–12.4 cm, orbicular, rounded at apex, cordate at base, nearly glabrous and green adaxially, densely pubescent along the midribs abaxially and ferruginous when dry; margin irregularly serrate to crenate; secondary veins 7–9 at each side. Inflorescence a lax cyme, axillary, 7.5–13.5 cm long, 4–36 flowers; peduncle 7.2–19.1 cm long, with uneven and 0.2–0.5 mm long hairs; bracts 2, opposite, 6–7 × 3–4 mm, lanceolate, acute at apex, slightly cordate at base, midrib and margins with short and dense hairs; bracteoles narrowly lanceolate, with short hairs at apex. Flowering pedicels 7–28 mm long, glabrous or with sparsely hairs unequally in length; calyx campanulate, zygomorphic; lobes 5, divided to half or deeply to base, unequal, two abaxial lobes 1.8–2.2 × ca. 1 mm, oblong, three adaxial lobes ca. 1 mm × ca. 1 mm, broadly triangular, acute to acuminate at apex, sparsely hispid abaxially. Corolla rose-pink, zygomorphic, ca. 1.2 cm long, tube ca. 8 mm long, broadly tubular; adaxial lip 3–5 × 6–7 mm, slightly bilobed, lobes broadly triangular, recurved; abaxial lip 3-lobed, 4–6 × 2–3 mm, lobes oblong to elliptic. Stamens 2, included; filaments adnate to the corolla base and free at upper part, ca. 3 mm long, slightly curved, glabrous; anthers ca. 0.8 × 1.9 mm, spheroid, glabrous, cohering by adaxial surfaces; staminodes 2, adnate to adaxial side at ca. 3 mm from base of corolla tube. Ovary ca. 7 mm long, linear, glabrous, 1-loculed, placentas 2, parietal, intrusive, bifid, recurved. Styles ca. 4 mm long, glabrous, strongly deflected off center to the left or right; stigma capitate; ovules many. Capsule 15–32 × ca. 3 mm, straight, linear, loculicidal dehiscing to base, valves 2, not twisted. Seeds many, ca. 0.3 × 0.1 mm, ovoid or ellipsoid, without appendage, brown.

Phenology: —Flowering from April to May; fruiting from May to July. Etymology: —The specific epithet refers to the type locality of this species. Distribution and habitat: — Gyrocheilos taishanense is currently only found on Mt. Nanfengshan, Taishan,

Jiangmen City, Guangdong Province, China. It grows in secondary broad-leaf forests on mountain slopes with 60–

70% canopy density and in mountain valleys. Associated plants mainly include Castanopsis fissa (Champ. ex Benth.)

Rehder & E. H.Wilson, Psychotria serpens L. and Conchidium pusillum Griff.

Additional specimens examined for taxa in this study

Gyrocheilos chorisepalum W.T.Wang :— CHINA. Guangxi Zhuang Autonomous Region: Nanning City , Wuming County, Mus . Guangxi 381 (holotype IBSC0097119 ), Xie Guanggan et al. 2-72 (paratype PE00154195 ) ; Shanglin County, Cai Canxing 5149 (paratypes IBK00191640 , IBSC0004893 ) .

Gyrocheilos chorisepalum var. synsepalum W.T. Wang (1982: 135) :— CHINA. Guangxi Zhuang Autonomous Region: Yulin City, Beiliu , Beiliu Exped. 8-4031 (holotype GXMI050706 ), Fabrica Med. Pingzheng 6761 (paratype GXMI050707 ) ; Guangdong Province: Nanzhidi 4099 (paratype IBSC0549587 ) .

Gyrocheilos lasiocalyx W.T.Wang :— CHINA. Guangxi Zhuang Autonomous Region: Guigang City, Guiping , Guiping Exped. 8-327 (holotype GXMI050708 ), Liang Naikuan 10757 (paratype IBSC0549589 ).

Gyrocheilos microtrichum W.T.Wang :— CHINA. Guangdong Province: Maoming City, Xinyi , C. Wang 32143 (holotype IBSC0004893 ; isotypes IBK00054510 , IBK00054512 ), C . Wang 38118 (paratypes IBSC0549591 , IBK00054511 ) .

Gyrocheilos orbiculatum D.J.Middleton :— VIETNAM. Petelot s.n. (holotype E00697919 ; isotypes P 04021810, P 04021811).

Gyrocheilos retrotrichum W.T.Wang :— CHINA. Guangdong Province: Maoming City, Xinyi, S. P. Kao 51222 (holotype IBSC0649582 ; isotypes IBK00191641 , IBSC0004871 , IBSC0004872 , IBSC0004894 , PE00030815 , PE00154201 , PE00030815 ).

Gyrocheilos retrotrichum var. oligolobum W.T.Wang :— CHINA. Guangxi Zhuang Autonomous Region: Liuzhou City, Rongshui , Chen Shaoqing 8902 (holotype IBSC0004895 ; isotype IBK00191642 ); T.Chen 16 (paratypes IBK00191643 , IBSC0549607 ); Chen Shaoqing 14122 (paratypes IBK00054514 , IBSC0549606 ) .

Figures

FIGURE 2. Gyrocheilos taishanense G.T. Wang, Yu Q. Chen & R.J. Wang, A: Habit, B–C: Adaxial and abaxial side of leaf blade when dry, respectively, D: Inflorescence and peduncle with unequal hairs, E: Zygomorphic calyx, F: Inflorescence, G: Longitudinal section of flower, H: Style and Ovary, I: Stamens (left two) and staminodes (right two), J–K: Capsules, L: Transverse section of capsule, M: Seeds.