All Floras      Advanced Search
Pakistan V. 206 Page 177 Login | eFloras Home | Help
Pakistan | Family List | Pakistan V. 206 | Cyperaceae

21. Kobresia Willd., Sp. Pl. 4: 205. 1805; C.B.Clarke in Hook.f., Fl. Brit. Ind. 6: 694. 1894.

Tufted perennials, seldom stoloniferous. Stem trigonous to terete, mostly smooth. Leaves from ΒΌ to overtopping stem length, basal sheaths often conspicuous, hard and stiff, or soft and thin, blades from filiform, nearly unifacial to keeled, 3.5 mm wide; ligule present. Inflorescence from spike-like (called spike below) to small paniculodium. Flowers unisexual; sometimes distal part of inflorescence containing staminate and proximal part pistillate flowers. Utricles (prophylls) from open to nearly completely closed; rachilla with or without staminate flowers. Stamens 2-3, stigmas 2-3. Identification of Kobresia species requires a special attention to be given to the inflorescence structure. The inflorescences may be clearly branched, i.e. the lateral branches are definitely elongated forming thus a small paniculodium. However, as the female flower is always, even in spike-like inflorescences, only born in the axil of a prophyll, i.e. in the axil of the first leaf of a lateral branch, an inflorescence containing female flowers is by definition not a spike but a multiple spike. The lateral branch can, in Kobresia, always be detected within the utricle (prophyll). Nevertheless, for practicel purposes, an inflorescence is being called a spike, when even on the lowest lateral branch is but one utricle, and a multiple spike when the lateral branches are elongated and bear more than one utricle; exceptions are indicated (e.g. K. schoenoides). The lateral branch or rachilla may remain within or extend from the utricle. Kobresia species, and Carex, are characterized by the unisexual flowers and by the utricle (prophyll) immediately surrounding the gynoecium. The term utricle is used below irrespective whether margins of the prophyll are more or less fused or open. In Kobresia the transformed prophylls, utricles, do not have a clearly differentiated beak and are not or not completely closed as in Carex, especially in the basal parts of the inflorescence. Kobresia differs from Carex also in having an axis extension, rachilla, which extends from within the utricles; the rachilla bears one or more male flowers, or is sterile and then often remains within the utricle. Also the use of the term glume requires in Kobresia (and Carex) an explanation. Normally glume refers to a scale (leaf) supporting the flower. In case of unisexual male flowers the application is clear. Application in case of the female fowers, however, born in the axil of prophylls or utricles is not the same; here the glume refers to a glume-like bract supporting a reduced lateral branch, rachilla. Nevertheless, in the following the term glume is used for these glume-like bracts. The bract again, by definition, refers to a (mostly) green leaf with more or less expanded blade supporting an extended lateral branch as e.g. in K. laxa.

The genus Kobresia is insufficiently known and in need of revision. It contains, probably, less than 50 species, mostly concentrated in the E Himalayas and SW China; represented in Pakistan by 11 species.


1 Inflorescence a small, lax paniculodium, lowest bract often overtopping inflorescence .   1 K. laxa
+ Inflorescence a spike (i.e. lateral spike with a single pistillate flower) or compact paniculodium (i.e. lateral spikes with 2 or more pistillate flowers), lateral spikes closely imbricated, lowest bract short.   (2)
       
2 (1) Inflorescence a compact paniculodium (see also K. humilis and K. schoenoides).   2 K. royleana
+ Inflorescence a spike.   (3)
       
3 (3) Plants dioecious or inflorescence androgynous (i.e. male flowers in distal part of spike); lateral branch short, within utricles (rachilla), mostly sterile or with 1-2 male flowers.   (3)
+ Plants monoecious; lowest lateral branches elongated, mostly with one utricle (female flower) and to 10 distal male flowers.   (4)
       
4 (3) Leaves to 1 mm wide; utricles 5.3-6.3 x 0.7-0.8 mm.   10 K. nepalensis
+ Leaves 2-3 mm wide; utricles 1.9-3 x 0.4-0.7 mm.   11 K. esenbeckii
       
5 (5) Plants to 5 cm tall, when taller then stoloniferous; spike few-flowered to 10 mm long.   (5)
+ Plants 5-47 cm tall; spike many-flowered more than 10 mm long.   (6)
       
6 (5) Plants tufted; stigmas 3.   8 K. pygmaea
+ Plants stoloniferous; stigmas 2.   9 K. macrantha
       
7 (7) Plants rather loosely tufted, up to 20 cm tall; basal sheaths soft, mostly pale brown, 10-20 mm.   (7)
+ Plants very tightly tufted, up to 47 cm tall; basal sheaths rigid, mostly dark black.brown, 20-75 mm.   (8)
       
8 (7) Spike 7-12 mm long; nut 2.8-3.7 x 1.1-1.3 mm, obovoid to ellipsoid.   3 K. humilis
+ Spike 15-30 mm long; nut c. 2.3 x 0.6 mm, fusiform.   7 K. duthie
       
9 Stem 11-47 cm, 0.5-1.3 mm diam, terete; inflorescence 10-46 x 2-4 mm; utricles 2.7-4.3 mm.   5 K. capillifolia
+ Stem 5-47 cm, 0.7-2 mm diam., obtusely angulate to terete; inflorescence 10-25 x 4-8 mm; utricles 4.2-5.8 mm.   (10)
       
10 (9) Stem 15-47 cm; leaves clearly shorter than stem, up to 3 mm wide; lowest lateral branches of inflorescence often with several feemale flowers; utricles open; rachilla with 3-10 male flowers.   4 K. schoenoides
+ Stem 5-27 cm; leaves from shorter to longer than stem, up to 1.3 mm wide; lowest lateral branches of inflorescence with one female flower: utricles closed; rachilla with 1-2 male flowers.   6 K. nitens

  • List of lower taxa


     

    Related Objects  

    Flora of China  
  • Kobresia (PDF)
  • PDF

  •  |  eFlora Home |  People Search  |  Help  |  ActKey  |  Hu Cards  |  Glossary  |