Bot. Bull. Acad. Sin. (1998) 39: 213_216

Peng and Lammers — Triodanis (Campanulaceae) in Taiwan

Triodanis Raf. (Campanulaceae: Campanuloideae), a new

generic record for the flora of Taiwan

Ching-I Peng^1,3 and Thomas G. Lammers²

¹Institute of Botany, Academia Sinica, Nankang, Taipei, Taiwan 115

²Department of Botany, Center for Evolutionary and Environmental Biology, Field Museum of Natural History, Chicago, IL 60605-2496, USA

(Received 12 March 1998; Accepted April 22, 1998)

Abstract. Triodanis biflora (Ruiz & Pav.) Greene (Campanulaceae), a slender, annual herb, was collected recently from Taiwan. It represents a new record for both the species and the genus on this island. The present study provides a key to the genera of Campanuloideae in Taiwan and gives a taxonomic account for this naturalized plant species.

Keywords: Campanulaceae; Campanuloideae; New record; Taiwan; Triodanis biflora.

Triodanis was not reported in treatments of Campanulaceae of Taiwan (Huang, 1979; Kao and DeVol, 1974, 1978; Lammers, 1992). During the course of the botanical inventory of Taiwan, Triodanis biflora was collected by the senior author from the lowlands of northwestern Taiwan, apparently as a naturalized weed. Although we have not witnessed its spread since it was discovered, it is appropriate to document the discovery of this species in Taiwan. To make the information available for Volume 4 (sympetalous dicots) of the second edition of the Flora of Taiwan, we hereby provide a taxonomic account of the newly recorded genus and species.

Key to Genera of Campanuloideae in Taiwan

1. Fruit loculicidal, dehiscent above the calyx lobes, or if indehiscent, all or most of the mature berry superior to the calyx lobes.

2. Stems twining; corolla 15_35 mm long Codonopsis

2. Stems erect or ascending; corolla 5_12 mm long.

3. Terminal flowers in 3-flowered cymes; calyx lobes pinnatifid, inserted at base of hypanthium; corolla lobes 6; fruit a berry Cyclocodon

3. Terminal flowers solitary; calyx lobes entire, inserted at summit of hypanthium; corolla lobes 5; fruit a capsule Wahlenbergia

1. Fruit poricidal, dehiscent below the calyx lobes, or if indehiscent, the berry crowned by the calyx lobes.

4. Plants with slender creeping stolons; corolla 3_8 mm long; seeds 10_16, relatively large, released through irregular rupture of the thin membranous pericarp Peracarpa

4. Plants with fibrous or fleshy roots but no stolons; corolla 8_30 mm long; seeds more numerous, small, released via 3 definite pores.

5. Plants perennial; all flowers chasmogamous; nectar disc large, tubular, surrounding the style Adenophora

5. Plants annual; only one or a few flowers chasmogamous, the rest cleistogamous; nectar disc absent or flat.

6. Inflorescence panicle-like, the flowers pedicellate; capsule broadly ellipsoid Campanula

6. Inflorescence spike-like, the flowers sessile; capsule cylindrical Triodanis

TRIODANIS Raf., New Fl. N. Amer. 4: 67. 1838.— Lectotype: T. rupestris Raf. [= T. perfoliata (L.) Nieuwl.]. Designated by: McVaugh, Wrightia 1: 23. 1945.

Dysmicodon (Endl.) Nutt., Trans. Amer. Philos. Soc. (n. s.) 8: 255. 1842. Based on: Specularia [no rank indicated] Dysmicodon Endl., Gen. P1. 518. 1838. Lectotype: Campanula flagellaris Kunth [=T. perfoliata]. Here designated!

Campylocera Nutt., Trans. Amer. Philos. Soc. (n. s.) 8: 257. 1842. Specularia sect. Campylocera (Nutt.) A. Gray, Proc. Amer. Acad. Arts 11: 82. 1876. Type: Campylocera leptocarpa Nutt. [T. leptocarpa (Nutt.) Nieuwl.]

Annual herbs; stems erect or reclining, unbranched or sparingly branched from lower nodes, 5-angled. Leaves toothed, sessile or short-petiolate, imperceptibly passing into floral bracts above. Flowers sessile, 1_3 (-8) in axils of upper leaves, forming a spike-like inflorescence, lower ones generally smaller and cleistogamous; calyx lobes 3_5; corolla 5-lobed, rotate, lobes narrowly triangular or elliptic, longer than the tube, acuminate at apex; stamens 5,

³Corresponding author. E-mail: bopeng@ccvax.sinica.edu.tw

Botanical Bulletin of Academia Sinica, Vol. 39, 1998

distinct, free from corolla; filaments expanded at base; anthers linear, longer than filaments; ovary inferior, 3-loculed with axile placentae (rarely 1-loculed with parietal placenta); stigma 3-lobed. Fruit an erect linear, oblong, ellipsoid, or clavate poricidal capsule with one pore per locule; seeds lenticular, dark brown, small, numerous.

Nearly endemic to North America, from southern Canada to Guatemala, with one species [T. biflora (Ruiz & Pav.) Greene] extending south to Argentina and Chile. Triodanis perfoliata is found throughout the North American range of the genus, while the remainder of the species [T. coloradoensis (Buckley) McVaugh, T. holzingeri McVaugh, T. lamprosperma McVaugh, T. leptocarpa (Nutt.) Nieuwl., and T. texana McVaugh] are endemic to the central and western United States. The solitary species reported from the Old World, T. falcata (Ten.) McVaugh, was treated as Legousia falcata (Ten.) Fritsch by Tutin (1976).

The genus has been merged by some authors with the Eurasian genus Legousia Durande (ºSpecularia Heist. ex A. DC., nom. illeg.). It is one of only three genera of Campanuloideae (out of 47 total) endemic to the New World.

Triodanis biflora (Ruiz & Pav.) Greene, Man. Bot. San Francisco 230. 1894. Figure 1

Campanula biflora Ruiz & Pav., Fl. Peruv. 2: 55. 1799.

Lobelia humboldtiana Willd. ex Scultes. in Roem. & Schultes, Syst. Veg. 5: 68. 1819.

Campanula montevidensis Spreng., Syst. Veg. 1: 738. 1824.

Specularia biflora (Ruiz & Pav.) Fisch. & C. A. Mey., Index Sem. Hort. Petrop. 2: 22. 1836, nom. illeg.

Dysmicodon ovatum Nutt., Trans. Amer. Philos. Soc (n. s.) 8: 256. 1842.

Dysmicodon californicum Nutt., Trans. Amer. Philos. Soc. (n. s.) 8: 256. 1842.

Specularia ovata (Nutt.) Vatke, Linnaea 38: 173. 1874, nom. illeg.

Specularia californica (Nutt.) Vatke, Linnaea 38: 714. 1874, nom. illeg.

Pentagonia biflora (Ruiz & Pav.) Kuntze, Revis. Gen. P1. 381. 1891, nom. illeg.

Legousia biflora (Ruiz & Pav.) Britt., Mem. Torrey Bot. Club 5: 309. 1894.

Figure 1. Triodanis biflora. A, habit; B, upper portion of a fruiting stem, showing poricidal capsules.

Peng and Lammers — Triodanis (Campanulaceae) in Taiwan

Specularia perfoliata f. ramosa Arechav., Anales Mus. Nac. Montevideo 7: 14. 1909, nom. illeg.

Specularia perfoliata f. rigida Arechav., Anales Mus. Nac. Montevideo 7: 14. 1909, nom. illeg.

Triodanis perfoliata var. biflora (Ruiz & Pav.) T. R. Bradley, Brittonia 27: 114. 1975.

Asyneuma anhuiense B. A. Shen, Acta Phytotax. Sin. 26: 463. 1988.

Stems usually 10_80 cm tall, 1_2 mm diameter. Leaves ovate to broadly elliptic, 0.5_3 cm long, 0.7_1.2 cm wide, rounded, obtuse, or acute at apex, cordate or cuneate at base, margins crenate, sessile. Flowers mostly cleistogamous, only the upper one (rarely few) open; calyx lobes triangular, lanceolate, or ovate, 1_7 mm long, 0.3_3 mm wide; corolla of open flowers lavender-blue (rarely white), 5_11 mm long, lobes 4_9 mm long, 2_4.5 mm wide; ovary (2_)3-loculed. Capsule oblong to clavate, 4_7 mm long, 1.3_2 mm in diameter; seeds elliptic in outline, 0.5_0.6 mm long. Gametic chromosome number, n = 14, 28.

Specimens examined. TAIWAN. Hsinchu Hsien: Chutung, Wufengli. Cement cracks of an abandoned village house, elev. ca. 110 m. 17 Mar 1991, Ching-I Peng 13708 (F, HAST).

Notes. Triodanis biflora is native throughout much of the southern United States, from Virginia to Oregon, south into northern Mexico. It is also believed to be native to South America, occurring sporadically in the central Andes and temperate southern portions of that continent. It is sparingly naturalized in the Hawaiian Islands (Lammers, 1990) and on the Chinese mainland, in Anhui, Zhejiang, and Fujian provinces (Chen et al., 1992; Shen, 1988). An illustration of Triodanis biflora is available in Shen (1988), as Asyneuma anhuiense B. A. Shen.

Acknowledgments. This work was supported in part by research grants from the National Science Council and Council of Agriculture, Taiwan to Ching-I Peng.

Literature Cited

Chen, L.-J., Z.-Y. Li, and D.Y. Hong. 1992. Triodanis Raf.—a new recorded genus of Campanulaceae in China. Acta Phytotax. Sin. 30: 473_475.

Huang, T.-C. 1979. A check list of the vascular plants of Taiwan. II. Spermatophyta. In H.L. Li, T.S. Liu, T.C. Huang, T. Koyama, and C.E. DeVol (eds.), Flora of Taiwan, vol. 6. Epoch, Taipei, pp. 22_188.

Kao, M.-T. and C.E. DeVol. 1974. The Campanulaceae of Taiwan. Taiwania 19: 123_147.

Kao, M.-T. and C.E. DeVol. 1978. Campanulaceae. In H.L. Li, T.S. Liu, T.C. Huang, T. Koyama, and C.E. DeVol (eds.), Flora of Taiwan, vol. 4. Epoch, Taipei, pp. 737_764.

Lammers, T.G. 1990. Campanulaceae. In W.L. Wagner, D.R. Herbst, and S.H. Sohmer (eds.), Manual of the Flowering Plants of Hawaii. University of Hawaii Press, Honolulu, pp. 420_489.

Lammers, T.G. 1992. Systematics and biogeography of the Campanulaceae of Taiwan. In C.-I Peng (ed.), Phytogeography and Botanical Inventory of Taiwan. Institute of Botany, Academia Sinica, Monograph Series No. 12, pp. 43_61.

McVaugh, R. 1945. The genus Triodanis Rafinesque, and its relationships to Specularia and Campanula. Wrightia 1: 13_52.

Shen, B.-A. 1988. A new species of Asyneuma Griseb. et Schenk from China. Acta Phytotax. Sin. 26: 463_464.

Tutin, T.G. (ed.) 1976. Campanulaceae. In T.G. Tutin, V.H. Heywood, N.A. Burges, D.M. Moore, D.H. Valentine, S.M. Walters, and D.A. Webb (eds.), Flora Europaea, vol. 4. Cambridge University Press, Cambridge, pp. 74_102.