J Syst Evol ›› 1979, Vol. 17 ›› Issue (4): 61-71.

• Research Articles • Previous Articles     Next Articles

A taxonomic study of the genus Hippolytia Poljak.

Shih Chu   

  1.  (Institute of Botany, Academia Sinica)
  • Online:1979-11-18 Published:1979-11-18

Abstract: The present paper is an attempt to propose a preliminary taxomomic treatment of the genus Hippolytia Poljak. and to analyse the geographical distribution of its composite elements. This small genus with 17 species is divided into 2 sections, namely, section Anthodesma Shih and section Hippolytia. Anthodesma is a small section with 3 species and is characterized by fascicled corymbs, campanulate and nitid involucres, rigidly herbaceous phyllaries, and undershrubs, while Hippolytia consisting of 14 species is characterized by corymbose inflorescence or glomerules or compund heads, cuneate and unpolished involucres, herbaceous phyllaries with pitch black margines. There are 12 species of Hippolytia in China, of which 3 are proposed as new in the present paper. Regarding the distribution pattern of Hippolytia, it is noteworthy to note that its range of distribution forms a more or less U-shape as shown in map 2. It may be seen that Hippolytia distributes in Central Asia-Sino-Himalaya-Median Asia. Section Anthodesma Shih occurs in central Asia, while section Hippolytia in the whole Himalayan region and northern Meridional Ranges and Median Asia. There seems to be no center of species concentration within the total range of Hippolytia, whose species are localized in distribution, for example, H. desmantha Shih is known only from Qinghai provence (Yu-Shu-Hsien), H. alashanensis (Ling) Shih is restricted to Ninghsia and central part of Kansu provence. It is interesting to note that H. yunnanensis (J. F. Jeffrey) Shih and H. longifolia (Wall.) Shih are referred to as vicarious species. The localization of the species distribution and the obvious discontinuity of morphological characters between species indicate a remarkable geographical influence on the species formation of Hippolytia. Hippolytia is an alpine genus of temperate zone of Asia, in which 64 per cent of species occurs at high elevations of above 3300m. altitude, 30 per cent of species are distributed in middle elevations of above 2200m. altitude. The life forms are microundershrubs, erect perennial herbs, glomerule stemless herbs or stemless herbs. It is very possible that its geographical origin and development may be linked up with occurance of desert steppe, especially of alpine meadow vegetations in the northern temperate zone of Asia. With regard to the geographical elements to which each species of Hippolytia belongs, it seems to indicate that H. trifida (Turcz.) Poljak., H. alashanensis (Ling) Shih and H. desmantha Shih belong to the geographical elements of central Asia, while H. yunnanensis (J. F. Jeffrey) Shih, H. glomerata Shih, H. tomentosa (DC.) Tzvel., H. senecionis (Bess.) Poljak. H. longifolia (Wall.) Shih, H. kennedayi (Dunn) Ling, H. syncalathiformis Shih, H. gossypina (Hook. f. et Thoms.) Shih and H. nana (C. B. Clarke) Shih to Himalayan elements, and H. darvasica (C. Winkl.) Poljak., H. megacephala (Rupr.) Poljak,, H. herderi (Rgl. et Schmalh.) Poljak. to Median Asia, H. delavayi (W. W. Smith) Shih to North-West-Yunna.

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