Bot. Bull. Acad. Sin. (2002) 43: 83-91

Ho et al. — Metagentiana, a new genus of Gentianaceae

Metagentiana, a new genus of Gentianaceae¹

Ting Nong Ho*, Shi Long Chen, and Shang Wu Liu

Northwest Plateau Institute of Biology, Chinese Academy of Sciences, Xining Qinghai, 810001, P.R. China

(Received June 1, 2000; Accepted April 16, 2001)

Abstract. The evidence from gross morphology, floral anatomy, chromosomes, palynology, and embryology all indicates that sect. Stenogyne is discordant within the genus Gentiana and is as distinct from the other sections of Gentiana as are other genera, such as Tripterospermum and Crawfurdia. In light of these characters, sect. Stenogyne is removed from Gentiana and given generic rank as the new genus Metagentiana. It is more related to Tripterospermum and Crawfurdia than to Gentiana, though it is more primitive than the first two genera. Together with Tripterospermum and Crawfurdia the new genus forms a monophyletic group, which is the sister group to the genus Gentiana. Fourteen new combinations required at specific rank are proposed.

Keywords: Gentiana; Gentianaceae; Metagentiana; New Genus; Taxonomy.

Introduction

Gentiana sect. Stenogyne was established by Franchet (1884) and was revised by Kusnezov (1894). It contains fourteen species: Ten of these are highly restricted to southwestern China; two are relatively widespread in northwestern and central China; one extends to eastern Burma from southwestern China, and one is endemic to Thailand. Stenogyne is the most disputable and poorly known of Gentiana's 16 sections. Smith (1965) considered it a somewhat mysterious group in Gentiana from its morphological characters, which suggested a closer affinity with Tripterospermum or Crawfurdia than with other sections of Gentiana. Löve and Löve (1976) recommended the transfer of this section to the genus Tripterospermum, tentatively as a subgenus (Tripterospermum subgen. Stenogyne). However, they had no karyological information to make a further delimitation. Yuan and Küpfer (1993) reported chromosome numbers for six species of this section for the first time and suggested a specialized and isolated position of this section in the genus Gentiana because of its higher and obviously secondary basic chromosome numbers x=17, 21, and 23. Three years later (Yuan et al.,1996), based on the nucleotide sequence of the internal transcribed spacer (ITS) of nuclear Ribosomal DNA, they further suggested excluding sect. Stenogyne from Gentiana and classifying it as a distinct genus. However, the necessary taxonomic changes were never made. Halda (1995) made sect. Stenogyne a subgenus, still positioned in the genus Gentiana. Since 1990, we have examined gross

morphology, floral anatomy, karyology, pollen morphology and embryology for most genera in the subtribe Gentianinae and have published a series of papers (Chen et al., 1997, 1998, 1999a, 1999b, 2000; Ho and Liu, 1990, 1999; Ho and Pringle, 1995; Ho et al., 1994, 1996, 1997, 1999, 2000; Liu and Ho, 1996a, 1996b, 1997; Xue et al., 1999a, 1999b). The present paper attempts to bring together these interactive studies of various materials relating to Gentiana sect. Stenogyne with the hope of better understanding its classification and systematic position.

Character Analyses

Based on detailed comparisons of characters such as gross morphology, floral anatomy, chromosomes, pollen morphology, and embryology, this study presents a complete documentation of Gentiana sect. Stenogyne. The concise descriptions of these characters used for the present study are as follows.

Gross Morphology

Most species in Gentiana sect. Stenogyne are annual herbs, but a few are perennials with extremely short rhizomes. The stem is erect and branched. Leaves are sessile, broadly ovate to ovate-triangular. Flowers are many, with each solitary and sessile at the end of stems and branches, subtended by a pair of leaf-like bracts. The calyx is tubular; midveins of the lobes are keeled and winged into the calyx-tube. The corolla is funnelform, and its plicae is long and wide. The margin of the plicae may be erose, denticulate, or fimbriate. The stamens are unequal and more or less curved downwards unilaterally. There are 5 nectaries at the base of the ovary. The style is filiform and about as long as the ovary. The capsules are cylindrical. The seeds are triquetrous with the three edges winged or rarely unwinged. Sect. Stenogyne is very

¹This project was financially supported by the Chinese National Natural Foundation.

*Corresponding author. E-mail: hotingnong@163.net

Botanical Bulletin of Academia Sinica, Vol. 43, 2002

special within Gentiana. It is similar to the remaining sections* of Gentiana in the characters of habit, stem, inflorescence, plicae etc. It is different from the remainder of Gentiana in the characters of calyx, stamen, style, and seed, but is similar to the genus Tripterospermum in these characters. Moreover, sect. Stenogyne is easily distinguished from all groups by its having sessile broad ovate to ovate-triangular leaves and large leaf-like bracts. Compared with the remainder of Gentiana, Tripterospermum, and Crawfurdia on gross morphology (Table 1), sect. Stenogyne is more similar to Tripterospermum than to the rest of Gentiana, because sect. Stenogyne is similar to the rest of Gentiana on the vegetative organs and similar to Tripterospermum on the reproductive organs.

Floral Anatomy

We have reported the floral anatomy of Gentiana sect. Stenogyne, Tripterospermum and Crawfurdia for the first

time (Chen et al., 1999b, 2000; Ho et al., 2000). The floral anatomic characters of sect. Stenogyne conform to the following basic framework of the subtribe Gentianninae. These main characters are: (1) the receptacle shows an amphiphloic siphonostele; (2) the calyx and corolla each have 5 traces dividing into three each; (3) squamellae, in the form of minute multicellular filaments, occur at the base of calyx tube; (4) the 5 stamen traces become 5 stamen vascular bundles; (5) the two carpels have 3 vascular bundles each (1 dorsal and 2 ventral). Besides these basic characters, sect. Stenogyne has some characters that differ from the rest of the subtribe, such as 12 sepal vascular bundles and vascular tissue entering the base of the secretory tissue of the nectaries. Compared with the remaining sections of Gentiana, Tripterospermum and Crawfurdia on floral anatomy (Table 2), sect. Stenogyne is considered an intermediate between the rest of Gentiana and Crawfurdia. The sepal vascular bundles

Ho et al. — Metagentiana, a new genus of Gentianaceae

Karyology

Chromosome numbers have been reported for eight species in sect. Stenogyne. These species have 2n=34, 42 and 46 chromosomes. Their basic number should therefore be X=17, 21 and 23. All of these species are considered diploids (Table 3a). Besides the chromosome numbers, karyotype analyses have been done for five species. Their karyotypes are more asymmetrical, with a higher proportion of submetacentric and acrocentric chromosomes. The classification of the karyotype belongs to 3A and 2B, rarely 2A types. The karyotypic asymmetry index (As. K%) has a mean value of 62.02 (Table 3b). Apparently, sect. Stenogyne is extremely special within Gentiana with

number 15 in the remaining sections of Gentiana, 10 in Crawfurdia, and 5 in Tripterospermum. The vascular tissue is conspicuously developed in Tripterospermum, weak in Crawfurdia, and absent in the remaining sections of Gentiana. The cohesion and reduction of vascular bundles were considered advanced characters by many researchers (Lindsey, 1940; Puri, 1951; Eames, 1961; Davis, 1966; Liang and Zhang, 1986). The vascular tissue in the nectary also was considered advanced by Deng (1995). According to evolutionary trends of floral anatomy, we consider that sect. Stenogyne is more primitive than both Crawfurdia and Tripterospermum, but is more advanced than Gentiana.

Botanical Bulletin of Academia Sinica, Vol. 43, 2002

respect to karyological characters (high secondary basic chromosome numbers and asymmetric karyotypes). In contrast, sect. Stenogyne is nearly identical to both Tripterospermum and Crawfurdia in these characters.

Embryology

Embryological data are a critical prerequisite to a complete understanding of the systematics of any taxon (Michael, 1991). We have studied embryology in twelve species of the subtribe Gentianinae. Among them Gentiana striata Maxim., Gentiana lawrencei var. farreri (I. B. Balfour) T. N. Ho, Crawfurdia delavayi Franch., and Tripterospermum cordatum (Marq.) H. Smith and T. chinense (Migo) H. Smith represent sect. Stenogyne, other sections of Gentiana, Crawfurdia, and Tripterospermum, respectively. The results indicated that the embryological characters of all four taxa conform to the basic framework of the subtribe Gentianinae: tetrasporangiate anthers; a dicotyledonous type of microsporangial development; simultaneous cytokinesis in the microsporocytes; tetrahedral microspore tetrads; 3-celled pollen; a superior, bicarpellary, and unilocular ovary; a unitegmic tenuinucellar ovule; a Polygonum type of megagametophyte; porogamous fertilization; nuclear endosperm; and a Physalis II variation of a Solanad type of embryogeny. Examining Table 4, it may be seen that the sect. Stenogyne is discordant with the reminder of Gentiana and differs from it in having a unitary original tapetum, uninuleate tapetal cells which do not protrude into the anther locule, middle layers of a 1-celled layer, a typical parietal placenta, a hypertropous ovule type, and ovules often arranged in four columns. The other sections of Gentiana have dual original tapetum, binucleate tapetal cells which elongate and protrude into the anther locule

to form "Trabeculae" and "Placentoids", 2-celled middle layers, a superficial parietal placenta, an anatropous ovule type, and ovules arranged in 10-30 columns. Sect. Stenogyne is more similar to both Tripterospermum and Crawfurdia than to the reminder of Gentiana in embryological characters. With sect. Stenogyne both Tripterospermum and Crawfurdia share the same unitary original tapetal and typical parietal placenta. In addition, Tripterospermum has the hypertropous ovule type while Crawfurdia has no "Trabeculae" or "Placentoids." Many researchers have discussed the evolutionary trends of embryological characters (Lindsey, 1940; Eames, 1961; Gopal, 1962; Johri, 1984; Tobe, 1989; Johri et al., 1992). Primitive embryological characters usually comprise: a thick anther wall, several middle layers, single origin of tapetum, typical parietal placentation, eight rows of ovules, and an anatropous ovule. Advanced embryological characters include: a thin anther wall, an ephemeral middle layer, an amoeboid (invasive or intrusive) tapetum, and superficial placentation. Based on these trends and a comparison of embryological characters, sect. Stenogyne, Tripterospermum, and Crawfurdia are more primitive than the remainder of Gentiana.

Palynology

We have examined the pollen morphology of 64 species representing Gentiana, Tripterospermum, and Crawfurdia with both light microscopy and scanning electron microscopy. As shown in Table 5, sect. Stenogyne is similar to the rest of Gentiana, Tripteropsermum, and Crawfurdia in basic pollen features such as spheroidal to subspheroidal pollen grains of medium size, with the wall striate-imperforate to perforate. However, most species in sect. Stenogyne are similar to the rest of Gentiana by hav

Ho et al. — Metagentiana, a new genus of Gentianaceae

ing lirae narrow (0.4-0.7 µm) and bacula erect, sometimes lobed at tops and arranged in one row at the collumellate layer, and a few species are similar to Tripteropsermum and Crawfurdia by having lirae wide (>1 µm) and bacula erect, not lobed at tops and arranged in two or more rows. Therefore, the pollen morphological characters of sect. Stenogyne are intermediate between the remainder of Gentiana and both Tripterospermum and Crawfurdia.

Systematic Position

Comprehensive comparative studies and synthetic analyses of the characters relating to gross morphology, floral anatomy, chromosomes, palynology and embryology indicate that (1) sect. Stenogyne is quite different from the other sections of Gentiana in the following respects: (A) karyology: a high secondary basic chromosome number and asymmetric karyotype; (B) embryology: a unitary original tapetum, uninuleate tapetal cells, no "trabeculae" or "placentoids", middle layers of 1-celled layer, a typical parietal placenta, a hypertropous ovule type, ovules often arranged in four columns; (C) gross morphology: a keeled and winged calyx-tube, unequal and unilaterally curved downwards stamens, a filiform and long style, and triquetrous seeds; (2) although sect. Stenogyne is similar to Tripterospermum and Crawfurdia in these karyological, embryological, and morphological characters, it differs from both in annuals, erect stems, many flowers solitary and terminal at ends of branches, and long and wide plicae, and also from Crawfurdia in characters of stamens, ovule type and fibrous thickenings of endothecium and from Tripterospermum in having no "trabeculae" or "placentoids"; (3) sect. Stenogyne is different from all taxa in sessile broadly ovate to ovate-triangular leaves, large leaf-like bracts, 12 sepal vascular bundles, and weak vascular tissue in nectaries.

The evidence from various characters indicates that sect. Stenogyne is discordant within the genus Gentiana and is as distinct from the other sections of Gentiana as other genera, such as Tripterospermum and Crawfurdia.

We here remove sect. Stenogyne from Gentiana and treat it as the new genus Metagentiana. As regards its systematic position, Metagentiana is more related to both genera Tripterospermum and Crawfurdia than to the genus Gentiana, though it is more primitive than the former. Together with Tripterospermum and Crawfurdia, the new genus forms form a monophyletic sister group to Gentiana.

Taxonomic Treatment

Metagentiana T. N. Ho & S. W. Liu, gen. nov.—TYPE: Metagentiana primulifolia (Franchet) T. N. Ho & S. W. Liu.

Gentiana sect. Stenogyne Franchet, Bull. Soc. Bot. France 31: 375 (1884). Gentiana subgen. Stenogyne (Franchet) Halda, Acta Mus. Richnov. 3: 29. 1995.—TYPE: G. primulifolia Franchet.

Hoc novum genus Gentianacearum Gentianae et Tripterospermo affine, a primo staminibus inaequalibus, ab apices unilateraliter decurvis, stylis filiformibus, ovario fere aequilongis vel longioribus, seminibus triquetris, cum anguste alis, a secundo floribus solitariis sessilibus, plicis corollae longis latisque, margine denticulatis usque fimbriatis, nectare parve, non discifore, ab utroque bracteis florum amplic foliaceis, vasculis calycis 12 bene recedit.

This new genus is related to Gentiana and Tripterospermum. It differs from the former by having stamens unequal and apically decurved, filiform style as long as the ovary, and seeds triquetrous with narrow wings on each edge. It differs from the latter by having flowers solitary and terminal at branches, corolla plicae long and wide with the margin erose to fimbriate, nectaries small, not disk-like. It differs from both by having large bracts at the bases of flowers and 12 vascular bundles in the calyx.

Annuals, rarely perennials. Stems erect, much branched from base or rarely simple. Flowers sessile, solitary, terminal on branches. Calyx keeled or winged. Plicae asymmetrical, very oblique. Style filiform, about as long

Botanical Bulletin of Academia Sinica, Vol. 43, 2002

as ovary. Capsules included in marcescent corolla, cylindric, wingless. Seeds triquetrous with three equal faces, the edges winged or rarely wingless; seed coat reticulate, rarely alveolate.

Distribution. China (Yunnan, Sichuan, Guichou, S Shanxi), Myanmar, Thailand. 14 species.

Key to Metagentiana and its Allied Genera

1a. Flowers ebracteate (except a few species in sect. Pneumonanthe); style linear to cylindrical, shorter than ovary; seeds ellipsoid, ovoid to globose, not triquetrous; calyx tube with 15 vascular bundles Gentiana L.

1b. Flowers bracteate; style filiform, as long as to longer than ovary; seeds triquetrous with three winged edges (rarely wingless); calyx tube with 5-12 vascular bundles.

2a. Stems erect, neither twining nor trailing; flowers sessile, solitary and terminal on branches; bracts as large as to larger than stem leaves; fruits included in persistent corolla; annuals, rarely perennials with stout and extremely shortened disclike-rhizome Metagentiana T. N. Ho & S. W. Liu

2b. Stems terete, twining or trailing; flowers pedicellate, 1-5 in terminal and axillary cymes; bracts much smaller than stem leaves; fruits exserted from persistent corolla; perennials with stout, long and branched rhizomes.

3a. Nectaries conspicuously developed, forming a collarlike disc around gynophore; stamens asymmetrical, unequal in length, apically decurved; fruit a capsule or berry; calyx tube with 5 vascular bundles Tripterospermum Blume

3b. Glands small, on gynophore; stamens equal in length, straight; fruits a capsule; calyx tube with 10 vascular bundles Crawfurdia Wallich

New Combinations

1. Metagentiana alata (T. N. Ho) T. N. Ho & S. W. Liu, comb. nov.

Gentiana kusnezowii Franchet, Bull. Soc. Bot. France 43: 492. Nov. 1896, non Gilg (May 1896). Gentiana alata T. N. Ho in T. N. Ho & S. W. Liu, Bull. Nat. Hist. Mus. London (Bot.) 23(2): 57. 1993.—TYPE: China, Yunnan, Kunming (Yunnan-fou), in 1895, Delavay s. n. (holotype: P!)

Distribution. China (C Yunnan). Clearingsin forests; 1,200-2,000 m.

2. Metagentiana australis (Craib) T. N. Ho & S. W. Liu, comb. nov.

Gentiana australis Craib, Bull. Misc. Inform. Kew 1916: 266. 1916. Gentiana leptoclada I. B. Balfour & Forrest

subsp. australis (Craib) Halda, Acta Mus. Richnov. 3: 30. 1995.—TYPE: Thailand, Siam, Doi Chieng Dao, on rocky ground, 1,650-1,770 m, 28 Jan 1913, A. F. G. Kerr 2865 (holotype: K!; isotypes: BM!, E!, P!).

Distribution. Thailand. Limestone rocks, scrub; 1,650-1,800 m.

3. Metagentiana eurycolpa (Marquand) T. N. Ho & S. W. Liu, comb. nov.

Gentiana eurycolpa Marquand, Bull. Misc. Inform. Kew 1931: 71. 1931. Gentiana gentilis Franchet subsp. eurycolpa (Marquand) Halda, Acta Mus. Richnov. 3: 30. 1995.—TYPE: China, Yunnan, [Kunming], Lagu (La-kou), on grassy hills, 2,400-3,000 m, Maire 7404 (holotype: UC!; isotypes: K!, US!). Paratypes: China, [Kunming], Kin-tchong- shan, 2,600 m, Maire 2910 (K!, UC!); without locality, Henry 10023 (K!, MO!, PE!).

Distribution. China (NE Yunnan, SW Sichuan, Guizhou). Grassland slopes; 2,400-3,000 m.

4. Metagentiana expansa (H. Smith) T. N. Ho & S. W. Liu, comb. nov.

Gentiana expansa H. Smith in Handel-Mazzetti, Symbolae Sinicae 7: 951. 1936.—TYPE: China, Yunnan, Yanjin Xian (Beyendjing), 28 Sep 1915, Semon Ten 282 (holotype: B, not seen, probably not extant; isotype: UPS!). Paratypes: China, Yunnan, Yanjin Xian (Beyendjing), 24 Sep 1919, Semon Ten 311 & 1393 (not seen); Binchuan (Bintschwan)—Dali, Dec 1906, Ducloux 4875 (P!).

Distribution. China (NW & C Yunnan). Grassland and gravel slopes, forest margins; 1,100-2,100 m.

5. Metagentiana gentilis (Franchet) T. N. Ho & S. W. Liu, comb. nov.

Gentiana gentilis Franchet, Bull. Soc. Bot. France 43: 491. 1896.—TYPE: China, Yunnan, Kunming (Yunnan Sen), Sep 1895, Delavay s. n. (holotype: P!).

Distribution. China (C & E Yunnan). Woodland margins, forests; 2,000-2,700 m.

6. Metagentiana leptoclada (I. B. Balfour & Forrest) T. N. Ho & S. W. Liu, comb. nov.

Gentiana leptoclada I. B. Balfour & Forrest, Notes Roy. Bot. Gard. Edinburgh 4: 71. 1907.—TYPE: China, NW Yunnan, Jinshajiang (Yangtse) Valley, [Deqen], Shiti-ko, 7,000-9,000 ft., Oct 1904, Forrest 7409 (holotype: E!; isotype: K!; typographic error "409").

Gentiana hapalocaula Marquand, Bull. Misc. Inform. Kew 1928: 52. 1928.—TYPE: China, NW Yunnan, [Lijiang], Tongshan in the Yangtze bend, 27°20' N, amongst grass in open situation, 3,000 m, Oct 1913, Forrest 11444 (holotype: E!; isotypes: BM!, K!).

Distribution. China (NW Yunnan, SW Sichuan). Valleys, forests; 2,100-3,000 m.

Notes. The stamens of G. leptoclada are unequal and variable (either some stamens longer than the corolla plicae or all shorter than the plicae). Gentiana hapalocaula

Ho et al. — Metagentiana, a new genus of Gentianaceae

was recognized as a distinct species in earlier treatments and distinguished from G. leptoclada by stamens shorter than the corolla plicae. Clearly, G. hapalocaula can not be maintained.

7. Metagentiana melvillei (S. Moore) T. N. Ho & S. W. Liu, comb. nov.

Gentiana melvillei S. Moore, J. Bot. (London) 43: 143. 1905. Gentiana primuliflora Franchet subsp. melvillei (S. Moore) Halda, Acta Mus. Richnov. 3: 30. 1995.—TYPE: Myanmar, Shan States, wayside at Pyinsamben, 3,000 ft., Oct 1903-Jun 1904, Melville s. n. (holotype: BM!).

Distribution. E Myanmar. Ca. 900 m.

8. Metagentiana primuliflora (Franchet) T. N. Ho & S. W. Liu, comb. nov.

Gentiana primuliflora Franchet, Bull. Soc. Bot. France 31: 375. 1884.—TYPE: China, NW Yunnan, Dapintze [of Heqing]—Mochechin [of Eryuan], in grasslands, 3 Oct 1882, Delavay Gent. n. 9 (holotype: P!; isotypes: E!, GH!, K!, UPS!).

Distribution. China (NW & C Yunnan, SW Sichuan). Grassland slopes, forests; 1,800-3,900 m.

9. Metagentiana pterocalyx (Franchet) T. N. Ho & S. W. Liu, comb. nov.

Gentiana pterocalyx Franchet in Forbes & Hemsley, J. Linn. Soc., Bot. 26: 132. 1890.—TYPE: China, NW Yunnan, Heqing (Hokin), 3,500 m, 18 Sep 1885, Delavay 1553 (holotype: P!; isotypes: E!, GH!, IBSC!, K!).

Distribution. China (NW & NE Yunnan, SW Sichuan). Grassland slopes; 1,700-3,500 m.

10. Metagentiana rhodantha (Franchet) T. N. Ho & S. W. Liu, comb. nov.

Gentiana rhodantha Franchet in Forbes & Hemsley, J. Linn. Soc., Bot. 26: 133. 1890. Syntypes: China, Hubei (Hupeh), Ichang: Maries s. n. (K!), Henry 964 (BM!, E!, GH!, IBSC!, K!, P!, PE!) & 2990 (K!, P!), 3986 (K!); NW Yunnan, [Heqing], Tapintze, 1,800 m, 15 Jun 1885, Delavay 1869 (BM!, GH!, K!, P!, UPS!); Yunnan, without locality, May 1886, Bourne s. n. (K!). Lectotype (designated here): Delavay 1869 (lectotype: P!; isolectotypes: BM!, K!, UPS!).

Gentiana jankae Kanitz, Pl. Exped. Szechenyi in As. Centr. Coll. 40. 1891.—TYPE: China, Yunnan, Jankae 252 (not seen).

Gentiana rhodantha Franchet var. wilsonii Marquand, Bull. Misc. Inform. Kew 1928: 55. 1928.—TYPE: China, W Hubei (Hupeh), without precise locality or altitude, Nov 1907, Wilson (Arn. Arb. Exped.) 2455 (holotype: K!; isotype: GH!).

Distribution. China (Yunnan, SW Sichuan, Guizhou, W Hubei, Henan, Gansu, S Shaanxi, Shanxi, Guangxi). Grasslands, scrub, forests; 500-2,000 m.

11. Metagentiana serra (Franchet) T. N. Ho, S. W. Liu & S. L. Chen, comb. nov.

Gentiana serra Franchet, Bull. Soc. Bot. France 31: 376. 1884.—TYPE: China, NW Yunnan, Dali (Tali)—Eryuan (Lan-kong), 6 Nov 1883, Delavay Gent. n. 13 (holotype: P!; isotypes: GH!, K!).

Gentiana pulchra H. Smith in Handel-Mazzetti, Symbolae Sinicae 7: 951. 1936.—TYPE: China, NW Yunnan, Lijiang (Lidjiang), Jun-Sep 1914-1916, Handel-Mazzetti 3751 (holotype:E!; isotype: UPS!). Paratypes: China, NW Yunnan, Lijiang (Lidjiang), 2,425-2,500 m, Handel-Mazzetti 7011 (BM!, E!), 3473 (E!), Forrest 2493 (BM!, E!); ibid., 2,950-4,400? m, Rock 5032 (E!, K!), 6174 (E!, IBSC!, K!, MO1, PE!, UPS!), 7788 (E!, IBSC!, K!, UPS!), 10715 (K1, MO!), 10748 (K!, PE!), 10839 (BM!, IBSC!, K!, P!), 10878 (IBSC!, K!).

Distribution. China (NW Yunnan). Meadows, forest margins, forests; 2,400-4,400 m.

Notes. Gentiana serra is a common species but easily confused with the other species of the genus. Gentiana pulchra was originally separated from G. serra supposedly by angular and unwinged seeds. However, the seeds of G. serra on the type specimen also are angular and almost unwinged. Actually, the seeds show variation from completely unwinged to narrowly winged on the angles in a number of gatherings we have seen.

12. Metagentiana souliei (Franchet) T. N. Ho, S. W. Liu & S. L. Chen, comb. nov.

Gentiana souliei Franchet, Bull. Soc. Bot. France 43: 491. 1896.—TYPE: China, W Sichuan (Se-tchuen), [Kangding], Tongolo and Tizou (Dzeura), Sep 1891, Soulie 194 (holotype: P!; isotype: K!).

Gentiana pterocalyx Franchet var. flavo-viridis Marquand, Bull. Misc. Inform. Kew 1928: 54. 1928. Gentiana souliei Franchet var. flavo-viridis (Marquand) Marquand, Bull. Misc. Inform. Kew 1937: 154. 1937. Syntypes: China, NW Yunnan, Lijiang (Lichiang), 27°30' N, in open stony mountain pasture, 3,400 m, Sep 1910, Forrest 6531 (BM!, E!, HNWP!, K!, MO!, PE!, UPS!); ibid., in open woods, 3,800 m, 2 September 1914, C. Schneider 2340 (BM!, E!, GH!, K!, P!); ibid., in stony alpine meadows, 3,600 m, 4 Sep 1914, C. Schneider 3135 (GH!, K!); Zhongdian (Chungtien), in alpine meadows, 3,600 m, 4 Sep 1914, C. Schneider 3002 (GH!, K!). Lectotype (designated here): Forrest 6531 (lectotype: E!; isolectotypes: E!, K!, UPS!).

Distribution. China (NW Yunnan, W Sichuan). Grassland slopes, stony slopes, alpine meadows, Abies forests; 3,200-3,900 m.

13. Metagentiana striata (Maximowicz) T. N. Ho, S. W. Liu & S. L. Chen, comb. nov.

Gentiana striata Maximowicz, Mém. Biol. Bull. Phys.-Math. Acad. Imp. Sci. St.-Pétersbourg 11: 265. 1881; Bull. Acad. Imp. Sci. St.-Pétersbourg 27: 501. 1881.—TYPE: China, W Gansu (Kansu), in alpine meadows, in 1872, Przewalski s. n. (holotype: LE, not seen).

Botanical Bulletin of Academia Sinica, Vol. 43, 2002

Gentiana tricholoba Franchet, Bull. Soc. Bot. France 43: 490. 1896.—TYPE: China, [W Sichuan], Kanding (Ta tsien lou), Soulie 134 (holotype: P!).

Gentiana schlechteriana Limpricht, Repert. Spec. Nov. Regni Veg., Beih. 12: 467. 1922.—TYPE: China, W Sichuan (as Ost.-Tibet), Kangding (Ta-tsien-lou), 3,900 m, Limpricht 1768 (holotype: WRSL, not seen; isotype: UPS!).

Distribution. China (E Xizang, W Sichuan, Qinghai, Gansu, Ningxia). Grassland slopes, alpine meadows, scrub; 2,200-3,900 m.

14. Metagentiana villifera (H. W. Li ex T. N. Ho) T. N. Ho & S. W. Liu, comb. nov.

Gentiana villifera H. W. Li ex T. N. Ho, Bull. Bot. Res., Harbin 4(1): 75, t. 2. January 1984; H. W. Li & C. Y. Wu, Acta Phytotax. Sin. 22(2): 156. April 1984.—TYPE: China, SE Sichuan, Junlian, on rocks in a valley, 800 m, 19 Apr 1959, Sichuan Econ. Pl. Exped. Yibin Sect. 18 (holotype: CDBI!; isotypes: KUN!, PE!, SZ!).

Distribution. China (SE Sichuan). Valleys; ca. 800 m.

Literature Cited

Chen, S.L., T.N. Ho, and J.Q. Liu. 1997. The chromosome numbers of eight species in Gentiana (Gentianaceae) from alpine mountains of the western China. Acta Bot. Boreali-Occidentalia Sin. 17(4): 547-550.

Chen, S.L., T.N. Ho, and D.Y. Hong. 1998. On systematic position of Pterygocalyx (Gentianaceae). Acta Phytotax. Sin. 36(1): 58-68.

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