A REVISION OF THE GENUS PARNASSIA (SAXIFRAGACEAE) IN CHINA
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After investigating the external morphology of the genus Parnassia the author realizes that the morphological variance of the staminodes may reflect the main evolutionary course of the genus and utilizes them as the criterion for discriminating the primary infrageneric taxa. The taxa with terete simple or 2-lobed staminodes are considered Primitive, while those with the flattened, lobed or deeply divided ones advanced. The characters of anther and petal margine and number of the cauline leaves are used to discern subsections and series. According to the point of view just mentioned, the classification constructed by Handel-Mazzetti (1941) is adopted here but with considerable addition and emendation. The conspectus of the revised classification for the chinese species is as follows. Sect. 1. Saxifragastrum. Staminodes terete simple, rounded and discoid at the apex. Ser. 1. Saxifragastrum. Basal leaves general 3——5 rarely 2 or 6——9. Ser. 2. Rosulatae. Basal leaves 10——20, rosulate. Sect. 2. Cladoparnassia. Staminodes tereta, 2-lobed at the apex. Sect. 3. Odontohymen. Staminodes flattened, 5——7-dentate at the apex. Sect. 4. Nectarotrilobos. Staminodes flattened, 3-lobed sel-dom 4——5-lobed. Subsect. 1. Nectarotrilobos Connective not projected at the apex. Ser. 3. Luteae. Scape without leaf. Ser. 4. Nectarotrilobos. Scape with one leaf. Ser. 5. Lijiangenses. Scape with two leaves. Subsect. 2. Xiphosandra. Connective projected at the apex. Sect. 5. Nectarobilobos. Staminodes 2-lobed, with equal lob-es. Scape with two leaves. Sect. 6. Allolobos. Staminodes flattened, 5-lobed seldom 6-lobed, with unequal lobes. Sect. 7. Fimbripetalum. Staminodes deeply divided into 3 filiform branches, each ending in a globose gland at the apex. Ser. 6. Amoenae. Petals fimbriate at the lower margin. Ser. 7. Fimbripetalum. Petals fimbriate around the whole margin. Sect. 8. Nectaroquinquelobos. Staminodes deeply divided into 5 filiform branches, each ending in a globose gland at the apex. Ser. 8. Gansuenses. Petals fimbriate at the lower margin. Ser. 9. Nectaroquinquelobos. Petals fimbriate at the whole margin. Sect. 9. Parnassia. Staminodes deeply divided into 7——23 filiform branches, each ending in a globose gland at the apex. The genus Parnassia consists of 9 sections and about 70 species, widespread in alpine regions of northern hemisphere,mainly of Asia. In the present paper 59 species, i. e. 82 percent of the total number of the genus, are recognized from China, 46 being endemic. In the montane regions of southwest China concentrate most of them, about 48 species, belonging to 7 sections, mainly including the two primitive ones, Sect. Saxi-fragastrum and Sect. Cladoparnassia, and the two more advanced ones, Sect. Odontohymen and Sect. Nectarotrilobos. Thus Southwest China is considered to be the centre of distribution and differentiation and also probably to be the contre of origin of the genus Parnassia.