NOVON 10: 398-399. 2000.

A New Species of Thladiantha (Cucurbitaceae) from Yunnan, China

Lu An-Ming

Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China

Charles Jeffrey

Komarov Botanical Institute, the Russian Academy of Sciences, St. Petersburg, Russia

Abstract. A new species, Thladiantha palmatipartita A. M. Lu & C. Jeffrey, is described from Yunnan, China. It differs from other species of the genus Thladiantha in its palmately 5-lobed leaves.

Thladiantha palmatipartita A. M. Lu & C. Jeffrey, sp. nov. TYPE: China. Yunnan: Fengkou (Fengke), 27E 40N N, 8000 ft., June 1914, George Forrest 12726 (holotype, E). Figure 1.

Species foliis palmatim 5-partitis a congeneris diversa. Herbae scandentes. Caulis sulcato-angulatus, leviter puberulus vel glabrescens, 1--3 m longus. Cirrhi simplices, pubescentes. Petiolus 3--7 cm longus; lamina ambitu late ovata vel orbiculata, 8--17 cm longa, 9--16 cm lata, chartacea, supra dense punctata, subtus dense pubescens, palmatim 5-partita, lobis oblongis, margine irregulariter dentatis, apice acutis vel acuminatis. Flores dioici. Flores masculi paniculati; pedunculus 2.5--3 cm longus, robustus, pubescens; pedicelli filiformes, 5--12 mm longi; tubus calycis cupularis, pubescens; segmenta 5, late lanceolata, 1.2--1.5 cm longa, ca. 5 mm lata, apice acuminata, trinervata; corolla campanulata, segmentis 5, oblongis vel lanceolato-oblongis, 1.5--1.8 cm longis, ca. 6 mm latis, apice acuminatis, trinervatis; stamina 5, filamentis 2 mm longis, antheris ca. 3 mm longis, unilocularibus. Flores feminei solitarii vel binales; ovarium anguste oblongum, villosum, 1.5--2 cm longum; stylus columnaris, apice trifidus, stigmatibus dilatatis, bifidis. Fructus oblongus, baccatus, indehiscens, apice rotundus, basi angustissime attenuatus, laevis, 7.5 cm longus, ca. 3.5 cm crassus. Semina numerosa, horizontalia, laevia, ca. 6 mm longa, 3 mm lata.

Scandent dioecious herbs. Stems sulcate-angular, 1--3 m long, puberulous or glabrescent. Tendrils simple, pubescent. Petioles 3--7 cm long, puberulous; leaf blade broadly ovate or orbicular in outline, 8--17 9--16 cm, chartaceous, adaxially densely punctate, abaxially densely pubescent, palmately deeply 5-lobed, lobes oblong, margin irregularly dentate, apex acute or acuminate. Flowers unisexual. Male flowers: panicle short, many-flowered; peduncle 2.5--3 cm long, robust, puberulous; pedicels slender, filiform, 5--12 mm long; calyx tube cupular, pubescent; segments 5, broadly lanceolate, 1.2--1.5 0.5 cm, apex acuminate, 3-nerved; corolla campanulate; segments 5, narrowly oblong or lanceolate-oblong, 1.5--1.8 0.6 cm, apex acuminate, 3-nerved; stamens 5; filaments 2 mm long; anthers ca. 3 mm long, 1-locular. Female flower solitary or paired, calyx and corolla as in the male; ovary narrowly oblong, villous, 1.5--2 cm long; style columnar, apically trifid; stigmas dilatate, 2-lobed. Fruit oblong, smooth, baccate, indehiscent, apex rounded, base attenuate, 7.5 cm long, ca. 3.5 cm diam. Seeds numerous, horizontal, smooth, ca. 6 mm long, 3 mm broad. Flowering in June and fruiting in September.

The new species differs from the other known species of Thladiantha (Li, 1997; Lu & Zhang, 1981) in its palmately deeply 5-lobed leaves. It is related to T. hookeri C. B. Clarke but differs by its calyx tube cupular, segments broadly lanceolate, 1.2--1.5 0.5 cm (rather than calyx tube broadly campanulate, segments narrowly triangular, ca. 4 1.5 mm).

Paratypes. CHINA. Yunnan: Yungning (Yongning), 27E 40N N, 8--9000 ft., female plant, June 1914, George Forrest 12440 (E); Yung-pe (Yongsheng), 26E 45N N, 9000 ft., in fruit, Sep. 1913, George Forrest 11166 (E).

Acknowledgment. The authors thank the curator of the herbarium of the Royal Botanic Garden, Edinburgh (E) for the loan of specimens.

Literature Cited

Li, J. Q. 1997. On the systematics of Thladiantha (Cucurbitaceae). Acta Bot. Yunnan. 19(2): 103--127.

Lu, A. M. & Z. Y. Zhang. 1981. A revision of the genus Thladiantha Bunge (Cucurbitaceae). Bull. Bot. Res. 1(1--2): 61--96.