Globba praetermissa J.Y. Jin, L. Bai & N.H. Xia, 2023

Jin, Jia Yi, Wang, Yi Hui, Xia, Nian He & Bai, Lin, 2023, Globba praetermissa (Zingiberaceae), a new species of G. sect. Globba from Yunnan, China, Phytotaxa 598 (2), pp. 173-181 : 175-178

Globba praetermissa J.Y. Jin, L. Bai & N.H. Xia sp. nov. Ả南ÞAEƊ【 diân nán wǔ huâ jiâng 】 Fig. 1

Type: CHINA, Yunnan province, Pu’er City, Simao City, Silan road , Macaohe Helmet , 100.764950° E, 22.658542° N, alt. 1135 m, 28 July 2022, L. Bai, J. Y. Jin & Y. H. Wang 028 (holotype IBSC!; isotypes HITBC!, IBSC!, KUN!)

Diagnosis: Similar to Globba purpurascens Craib (1912: 399) in having lax, pendent inflorescence, densely ciliate bracts and lateral staminodes which are nearly equal in length to the lateral corolla lobes; differs from the latter by upper leaf sheaths being green, laminae being ovate or elliptic and larger (16–21 × 4.5–6.5 cm), bracts being ovate, pale green, larger (lowermost ones ca 35 × 15 mm) and reflexed, pedicels being fully enclosed by bracteoles, calyx being longer (ca 5 mm long), six appendages including a smaller appendage between the two larger appendages on each side and ovaries being smooth. In G. purpurascens , the leaf sheaths are purple, laminae are ovate-lanceolate or lanceolate and smaller (6–11.3 × 1.1–3.2 cm), bracts are smaller (lowermost ones 12–20 × 3–5 mm), lanceolate, green with purple tinge and held at ca 90° to rachis, pedicels are not fully enclosed by bracteole, calyx are shorter (ca 3mm long), the number of appendages is four and ovaries are verrucose.

Description: Herb 60–100 cm tall. Rhizome composed of up to about three rhizome units, rhizome units globose, ca 7 mm in diam., pale brown externally, white internally; narrowly fusiform root tubers present in dry season. Leafy shoot 1–2 per plant, slightly arching, each with 7–9 well developed leaves; stem near the ground has several nodes which are enclosed by short and purple sheathes; leaf sheaths green, lower ones slightly tinged purple, densely pubescent with ciliate margins; ligule bilobed, lobes rounded at apices, 3 mm long, densely brown ciliate; petiole extremely short at lower leaves, slightly elongated to 5 mm on upper leaves; laminae ovate or elliptic, 16–21 × 4.5–6.5 cm, adaxially yellowish green, scabrid, abaxially pale green on upper leaves but purple on lower leaves, densely pubescent, base rounded, apex long acuminate. Inflorescence lax, pendent, panicle, 5–12 cm long; peduncle 1–2.5 cm long beyond leaf sheaths, pale green, densely yellowish pubescent; rachis the same color and indumentum; bracts persistent, ovate, basal ones ca 3.5 × 1.5 cm, upper ones smaller, pale green, becoming paler with age, reflexed, apex acute, densely pubescent and ciliate; cincinni present at axils of upper bracts, held at ca 45° to rachis, rachilla up to 4 cm long, straight, 8–12 mm to first flower, with flowers arranged in two rows at the apex; bracteole ovate, each subtending one flower, conduplicate alone its keel, bracteoles forming an equitant structure, basal ones ca 10 × 6 mm, upper ones slightly smaller, yellowish white, pubescent, sparsely ciliate, apex acute; pedicel 1–2 mm long. Flowers ca 3.5 cm long, orange-yellow; calyx tubular, ca 5 mm long, 2.5 mm in diam., yellow, pubescent, apex tri-lobed, lobes acute or acuminate, dorsal one slightly larger than the lateral two; floral tube narrowly infundibuliform, ca 1.7 cm long, ca 1 mm in diam. at base, ca 2 mm in diam. at apex, yellow-orange, pubescent externally, glabrous internally; corolla lobes yellow, adaxially glabrous, abaxially pubescent, dorsal one hooded with acute apices, elliptic, ca 6 × 1.5 mm, lateral two deltate, ca 5 × 2.5 mm, apex acute; nectar tube ca 8 mm long; labellum reflexed, deltate, ca 7 × 7 mm, basal 3 mm adnates to nectar tube, yellow with a red spot at center, base truncate, apex bilobed, lobes acute; lateral staminodes oblong, ca 7 × 2.5 mm, orange, glabrous on both sides, apex obtuse or retuse; filament ca 1.7 cm long; anther elliptic, ca 3 × 1.5 mm; lateral appendages 6, triangular, a smaller between the two larger appendages on each side, ca 0.5 × 0.2 mm, distal pairs being similar to proximal in size, ca 2 × 1 mm, orange; style filiform, as long as the flower; stigmas cup-shaped, with a ciliate margin; Ovary globose, pale yellow, smooth, pubescent, ca 3 mm in diam.; epigynous nectaries two, linear, 5–6 mm long. Fruit and seeds unknown. Bulbils present at axils of lower bracts, sometimes protruding from the leaf sheaths, globose, ovate or conical, with a corky texture, tan or grey, 8–20 mm long, 4–6 mm in diam.

Etymology: The epithet praetermissa means overlooked, referring to the fact that the species has long been confused with G. marantina .

Distribution: The species is currently known from Xishuangbanna Dai Autonomous Prefecture and Pu’er City, Yunnan province, southwestern China. It most like also occurs in adjacent areas of Laos and Myanmar, but we have not found any specimens from these regions despite a study of digitized specimens at E, K, L and P.

Ecology: Growing in shrubs at half shaded to shaded margin of monsoon rain forest, at an elevation of about from 550 m to 1300 m.

Phenology: According to our field observation and specimen records, the species flowers from June to September. Bulbils develop simultaneously with the flowers. No fruits were observed either in herbarium specimens or in the field. Two collections (S.J. Pei 59-10661, KUN!, J.Y. Jin JYJ066, IBSC!) of this species made in October and November respectively show that the inflorescences contain only bracts and bulbils. This species may not produce fruits, like G. marantina and several other species in G. sect. Globba ( Lim 1972a) .

Conservation status: The extent of occurrence (EOO) of the species is more than 33800 km 2. The IUCN status is proposed as “LC” (Least Concern), in accordance with the latest IUCN Criteria ( IUCN 2022).

Notes: In the past, the specimens of G. praetermissa were misidentified as G. barthei . The illustration and description of G. barthei in Flora Reipublicae Popularis Sinicae ( Wu & Chen 1981) and Flora of China ( Wu & Larsen 2000) were largely based on G. praetermissa . This study shows that G. marantina (= G. barthei ) indeed occurs in China, but its known distribution is restricted in east of Yunnan Province, northwest of Guizhou Province, west and north of Guangxi Province and south of Hainan Province (N.Q. Chen 43561, IBK!) and, with Hainan province representing a new provincial record of the species. A color plate of this species based on a collection from west Guangxi is given in Fig. 2 . The third member of G. sect. Globba in China, G. schomburgkii can be easily distinguished from G. praetermissa by its shorter leafy shoots (30–50 cm), long petiole (ca 5 mm), glabrous laminae, lax cincinni, ovate corolla lobes and globose or ovoid, smaller bulbils (2–4 mm in diam.).

Morphologically, G. praetermissa is most similar to G. purpurascens , a species distributed in northern Thailand and northern Laos. Apart from the few morphological differences listed in diagnosis, G. praetermissa differs from G. purpurascens by being a predominantly apomictic species, with no fruits observed in our field study or specimen examination, while fruits of G. purpurascens have been reported by Craib (1912). Furthermore, Larsen (1972) reported that G. purpurascens is a diploid species with 2n=32. Although we have not examined the chromosome of G. praetermissa, Li & Chen (2008) reported that G. marantina is a triploid with 2n=48 using material from Menghai County, Yunnan province. We have not been able to locate the voucher specimens cited, but the material is most likely G. praetermissa based on the origin and the reference source they consulted ( Gao et al. 2006).

Cao et al. (2019) reported three species possessing six appendages, one of which belongs to G. sect. Globba while the other two belong to G. sect. Sempervirens K. J. Williams in Williams et al. (2004: 114). Globba praetermissa is the second species with six anther appendages in G. sect. Globba . It can be recognized from other members of this section by all vegetative parts being hairy, short petiole, and pendent inflorescence with pale green and reflexed bracts, crowded cincinni, short pedicel, lateral staminodes which are almost as long as lateral corolla lobes and six appendages.

A detailed comparison of G. praetermissa , G. purpurascens and G. marantina is provided in Tab. 1 . The description of G. purpurascens is based on that in protologue, image of type specimen at E [barcode 00097493] with high quality and the online pictures in Souvannakhoummane (2015) and GBIF (2021). Description of G. marantina is based on its lectotype specimen, description of Smith (1806), Schumann (1904) and Gagnepain (1908) and collections mentioned below from China.

Other specimens examined (paratypes): Yunnan. Xishuangbanna Dai Autonomous Prefecture: Mengla , 14 July 1959, Y.H. Li 1615 ( KUN 0424527 , HITBC 048633 ); ibidem, 18 July 1959, Y.H. Li 1538 ( KUN 0424528 , HITBC 048633 & 048682); ibidem, 4 October 1959, S.J. Pei 59-10661 ( KUN 0424525 & 0424526); ibidem, 14 August 1959, H.T. Cai 9224 ( KUN 0424735 & 0424521); ibidem, 1 July 1988, H. Zhu 1402 ( KUN 0424581 ); ibidem, 21 June 1973, P.Z. Zhu 8679 ( HITBC 048677 , 048679, 048680 & 048682); ibidem, 23 August 2003, S.S. Zhou 163, ( PE 02010989 , HITBC 107156 ); ibidem, 1 August 2003, S.S. Zhou 160, ( HITBC 105557 , IBSC 0745179 ); ibidem, 18 July 2011, S.S. Zhou 10393 ( HITBC 142259 ); ibidem, 18 July 2011, S.S. Zhou 10398 ( HITBC 142264 ); Jinghong , 20 September 2002, S.S. Zhou 499 ( HITBC 104743 ); ibidem, 17 August 1977, G.D. Tao 17591 ( KUN 0424592 , IBSC 0745323 , HITBC 048678 ); ibidem, August 1936, Q.W. Wang 77549 ( KUN 0424519 , PE 00074744 , 00074745 & 00074746, NAS 00556552 ); ibidem, 14 August 1991, Y.H. Li 362, ( KUN 1268350 ). Pu’er City: Jiangcheng , 16 August 2011, S.S. Zhou 10607 ( HITBC 142468 ); Simao , 3 July 2003, S.S. Zhou 905 ( HITBC 105413 ); ibidem, 13 July 2001, H. Wang 5219 ( HITBC 094831 , IBSC 0745236 ); Menglian, 9 July 1973, Meng Lian Expedition 9396 ( HITBC 048684 , KUN 0424530 & 0335301) .

Specimens of Globba marantina examined: Guangxi, Hechi City: Tian’e, 7 September 1939, 92774 (IBK 00137623, 00137624); ibidem, 20 August 1958, Z.T. Li 6012144 (IBK 00137622, KUN 0424532). Guizhou, Qianxinan Buyi and Miao Autonomous Prefecture: Anlong County, 16 September 1991, Dianqiangui Expedition 50387 (KUN 0735917); Xingyi City, 15 July 1960, Guizhou Expedition 6255 (IBSC 0022624). Hainan, Lingshui, 18 August 1930, N.Q. Chen 43561 (IBK 00137626). Yunnan, Wenshan Zhuang and Miao Autonomous Prefecture: Xichou 5 July 2009, Yunnan Expedition YN-ET 824 (PE 02010960 & 02010961); Funing, 18 July 1982, S.W. Yu & Q.A. Wu 946 (KUN 0735922); ibidem, 27 October 1958, X.T. Cai 58-8924 (KUN 0424520); Honghe Hani and Yi Autonomous Prefecture: Hekou Yao Autonomous County, 28 July 1953, W.X. Liu 348 (KUN 0424522 & 0424550, IBSC 0022499).

Specimens of Globba purpurascens examined: Thailand, Chiang Mai, 7 August 1910, A. F. G. Kerr 1316 ( BM 013399527, E 00097493); ibidem, 19 July 1988, J.F. Maxwell 88-889 ( L 1479485). United States of America, Maryland, NMNH Botany Research Greenhouses, 26 July 2004, W. J. Kress 04-7692 ( US 00732878).

Figures

FIGURE 1. Globba praetermissa. A. Habitat; B. Inflorescence, apical view; C. Flower, front view; D. Abaxial view (left) and adaxial view (right) of lower leaves, indumentum of abaxial surface (left) and adaxial surface (right) laminae (inset); E. Inflorescence, side view; F. Bracts (upper), young bulbils collected in July (bottom right) and older bulbils collected in November (bottom left); G. Ligule; H. Cincinni (left) and cincinni with bracteoles removed (right); I. Bracteoles and flowers on a cincinnus; J. Root and lower stem in November (left) and in flowering phase (right); K. Cincinni; L. A dissection of a flower, lcl = lateral corolla lobe, dcl = dorsal corolla lobe, ls = lateral staminodes, lb = labellum, at = anther thecae, c = calyx, o = ovary (anther, calyx and ovary are preserved in alcohol). Scale bars: D = 3 cm; E = 2 cm; F– I & K– L = 1 cm. Photos by Jia Yi Jin.

FIGURE 2. Globba marantina from west Guangxi, China. A. Habitat; B. Inflorescence, apical view; C. Inflorescence, bulbils at the apex of inflorescence (inset); D. Flower, apical view; E. Flower, side view; F. Indumentum of adaxial (top) and abaxial laminae (bottom); G.A bract (left) and side view of a cincinnus (right); H. Back view (left) and front view (right) of a cincinnus with flowers removed (preserved in alcohol); I. Bracteoles (preserved in alcohol). Scale bars: G = 1 cm; H–I = 5 mm. A–E: Photos by Yu Song Huang. F–I: Photos by Jia Yi Jin.