A worldwide monograph of Swertia and allies（簡體書）

Ho Ting-nong、Liu Shang-wu編著的《獐牙菜屬和近緣屬的世界性分類修訂(英文版)》介紹了，獐牙菜屬及近緣植物中獐牙菜苦苷、龍膽苦苷、芒果苷、齊墩果酸的含量，為資源利用提供依據。獐牙菜屬（Swertia）是龍膽科下的一個屬，約100種，廣布于全球，我國約70余種，南北均產之。一年生或多年生草本。一年生或多年生草本；葉對生；花藍色或白色，有黃色的腺點，排成密錐花序式或傘房花序式的圓錐花序；萼片4－5深裂，每一裂片的近基部有窩孔或腺體1－2個，窩孔禿裸或一部為一基生的鱗片所覆蓋，其周邊或具睫毛；雄蕊4－5，著生于花冠的近基部，分離，很少合生成1束；子房1室，柱頭2；果為一卵形或長橢圓形的蒴果，成熟時分裂為2果瓣，有種子多數。

1 Inter-generic circumscription of Swertia and allies1.1 An introduction to the tribe GentianaThe tribe Gentiana circumscribed by Struwes and Albert (2002) prises 17 genera in two subtribes. Subtribe Gentianinae contains Gentiana， Crawfurdia， Tripterospermum， while subtribe Swertiinae includes Bartonia， Comastoma， Frasera， Gentianella， Gentianopsis Halenia， Jaeschkea， Latouchea， Lomatogonium， Megacodon， Obolaria， Pterygocalyx， Swertia and Veratrilla. Within the past three decades， we published three additional genera to be included in the Gentianae (Lomatogoniopsis， Metagentiana and Sinoswertia) (Ho and Liu， 1980; Ho et al.， 2002; He et al.， 2013b). Phylogeic analyses constructed based on molecular evidence suggested that after erecting Sinoswertia， the genus Swertia sensu lato was still polyphyletic (Yuan and Küpfer 1995; Chassot et al.， 2001; Liu et al.， 2001; He et al.， 2013b). However， a limited number of Swertia species were sampled. It remains elusive how many genera should be recognized within Swertia sensu lato. Here， we tentatively adopt the generic circumscriptions of most genera described by previous authors (for example， Struwes and Albert， 2002). In addition， we further place Frasera in Swertia sensu lato based on available morphological parisons. Thus， the Gentianae should prise 19 genera in total according to current taxonomic treatments. Both subtribes Gentianinae and Swertiinae can be easily distinguished by the presence or lack of corolla plicae and intracalycular membranes between lobes (Smith， 1936). The subtribe Swertiinae also may be subdivided into two groups: the Rotate group and the Tubular group (Smith， 1965). The former has a rotate corolla and calyx， with nectaries either naked or surrounded by fringed or tubular appendages， whereas the latter has a tubular corolla and calyx， with nectaries naked or absent (Ho and Liu， 2001). In the present book， we present a monograph of the rotate group prising Swertia， Sinoswertia， Lomatogoniopsis， Lomatogonium， and Veratrilla. 1.2 Key to genera of the tribe Gentiana and subtribe Swertiinae1a. Corolla with plicae extending between lobes (except in G. lutea L.); with an intracalycular membrane between lobes (except in Crawfurdia spp. and Tripterospermum spp.) (subtribe Gentianinae):2a. Flowers ebracteate at base (except for a few species in sections Pneumonanthe and Gentiana); style linear to cylindrical， shorter than ovary; seeds ellipsoid， ovoid to global， not triquetrous; calyx tube with 15 vascular bundlesGentiana L.2b. Flowers bracteate at base; style filiform， as long or longer than ovary; seeds triquetrous to pressed， with three edges; calyx tube with 5–12 vascular bundles:3a. Stems striate-angled， erect， neither twining nor trailing; flowers sessile， solitary and terminal at branches; bracts of flowers as large or larger than stem leaves; fruit included in persistent corolla; seeds triquetrous with narrow wings on edges， three edges forming three equal faces; annuals， rarely perennials with stout and extremely shortened disc-like rhizomeMetagentiana T. N. Ho and S. W. Liu 3b. Stems terete， twining or trailing; flowers 1–5， pedicellate， in terminal and axillary cymes; bracts of flowers much smaller than stem leaves; fruit exserted from persistent corolla; seeds pressed with discoid wings on edges， rarely triquetrous to pressed with narrow wings， three seed edges forming three extremely unequal faces; perennials with stout， long and branched rhizomes:4a. Nectaries conspicuously developed， forming a collarlike disc around gynophore; stamens， unequal， apically decurved; fruit a capsule or berry; calyx tube with 5 vascular bundlesTripterospermum Blume4b. Nectaries small， on gynophore; stamens symmetrical， equal， straight; fruits a capsule; calyx tube with 10 vascular bundlesCrawfurdia Wallich1b. Corolla without plicae between lobes; without intracalycular membrane between lobes (except Gentianopsis (subtribe Swertiinae):5a. Corolla rotate， lobed nearly to base， tube very short， indistinct， much shorter than lobes; nectaries surrounded by fringed or tubular appendages or naked:6a. Plants dioecious， with uniual flowers; seeds discoid-wingedVeratrilla Baillon ex Franchet6b. Plants with perfect flowers; seeds various:7a. Nectaries not surrounded by fringes or appendagesGentianella Moench7b. Nectaries surrounded by fringed or tubular appendages:8a. Both plants and flowers dimorphic: plants heterogeneous and homog-eneous; the former with a distinct main stem and numerous weak branches at stem base， on main stem flowers larger and nectaries linear-oblong fringed， on weak branches flowers 1/4–1/3 as large as those of main stem and nectaries with broadly oblong entire elevated scales and indistinct flat gland patches; the latter with uniform stems and flowers， flowers are the same in shape， size and nectaries as those of large-sized flowers on heterogeneous plantsSinoswertia T. N. Ho， S. W. Liu and J.