Carex perakensis

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Carex perakensis


Leaves basal and subbasal, rarely spaced throughout the stem, shorter than to exceeding the stem, flattish, rather stiff, scabrid or smooth on the margins, asperous towards the long acuminate apex, (2-)3-16 mm wide; Inflorescence usually consisting of 2-7 fascicles, or spikelets single, binate or ternate at each node;


Annam present, Asia-Temperate: China South-Central (Yunnan present), Asia-Tropical: Borneo present; Laos (Laos present); Malaya (Peninsular Malaysia present); Sumatera (Sumatera present); Thailand (Thailand present), Atjeh present, Kwangsi present, Lower Burma present, Pahang present, Palembang present, Perak present, S. China present, SW. & SE. Celebes present, Selangor present, Southern America: Argentina Northeast (Formosa present), Tonkin present
S. China (Yunnan and Kwangsi), Formosa, Tonkin, Annam, Laos, Lower Burma, Thailand; in Malesia: Sumatra (Atjeh, East Coast, Palembang), Malay Peninsula (Perak, Larut, Pahang, Selangor), Borneo, SW. & SE. Celebes.


The species is very variable, three varieties being distinguished. Carex borneensis seems at first sight to be a different species, although closely allied to C. vansteenisii s.s., because in most of the material of C. borneensis the spikelets are not compound. In the Malay Peninsula, however, this difference fades away, the spikelets of C. borneensis becoming also compound. Carex vansteenisii, a very rare plant, possesses exactly the same inflorescence as C. perakensis, the utricles are narrower, and their length overlaps with the range of those of C. perakensis (7-9 mm in C. vansteenisii, 5- 6(-8) mm in C. perakensis).
Nelmes distinguished also between C. borneensis and C. kinabaluensis, although there are no differences at all between the two. The Celebes collection (C. eymae Nelmes) is young and differs hardly from the Bornean specimens of C. borneensis.
Carex kinabaluensis was considered an ally of 57. C. brunnea, as Stapf made a mistake in describing it as having 2 stigmas (in fact the number of stigmas is the only difference between the two sections!).
In the specimens of C. borneensis from the Malay Peninsula, as mentioned in the first note, some of the spikelets are branched (into 2-4 secondary spikelets). On account of this Nelmes maintained C. breviglumis Ridl. as a species distinct from the Bornean plants of C. borneensis, in which the spikelets are usually unbranched. However, this difference does not always hold.
Nelmes considered C. tonkinensis and C. leucostachys specifically distinct from C. perakensis s.s., but I could not find differences, and his key characters are unfit for discrimination.
Carex leucostachys has been recorded from Pahang (P. Tioman), S. Sumatra (G. Pesagi), and Tonkin. In the type collection the inflorescence is a dense, head-like panicle, and the utricles are about 8 mm. The inflorescence is still too young for good description, but it shows resemblance with C. van- steenisii s.s. in the utricles, and several other collections show transitions to C. perakensis s.s.
Clarke based C. arridens on two collections (Lower Burma, Kurz, n.v., and Perak, King's coll. 2801). The Perak specimen, the only one ever collected in Malesia (in 1882) is very young with quite undeveloped flowers. It has the dark-nerved basal sheaths and the pale indumentum of the young utricles of C. perakensis s.s. The glumes are darker than is usual. In 1951 Nelmes placed it in subg. Carex, but C. perakensis, C. tonkinensis and C. leucostachys in subg. Indocarex. The two subgenera he distinguished by their cladoprophylls (utriculiform in subg. Indocarex, ocreiform in subg. Carex). He described the cladoprophylls of C. perakensis as "utriculi-glumiform", those of C. tonkinensis as "more or less ocreiform" of C. leucostachys as "subocreiform below, glumiform above" and of C. arridens as "subutriculiform below, glumiform above". In 1955 he removed C. tonkinensis to subg. Carex, C. leucostachys and C. perakensis he left in subg. Indocarex.


Nelmes 1951 – In: Reinwardtia: 333
C. B. Clarke 1925 – In: Fl. Mal. Pen.: 184
Raym. 1955: p. 165. – In: Nat. Canad.: f. 5
Raym. 1959 – In: Mem. Jard. Bot. Montreal: 74
Franch. 1951 – In: Reinwardtia: 254
C. B. Clarke 1951 – In: Reinwardtia: 253
Clarke 1925 – In: Fl. Mal. Pen.: 184
Raym. 1959: p. 74. – In: Mem. Jard. Bot. Montreal: f. 18
Ridl. 1907 – In: Mat. Fl. Mal. Pen. (Monoc.): 116
Clarke 1955 – In: Mem. Mus. Hist. Nat. Paris n.s.: 139
Kuk. 1909 – In: Pfl. R. Heft: 548
Ridl. 1955 – In: Mem. Mus. Hist. Nat. Paris n.s.: 113
Nelmes 1950: Kew Bull.: 189
C. B. Clarke 1935 – In: Uitt. Rec. Trav. Bot. Neerl.: 201
Ridl. 1907 – In: Mat. Fl. Mal. Pen. (Monoc.): 117
Kuk. 1909 – In: Pfl. R. Heft: 292
Koyama 1962 – In: J. Fac. Sc. Un. Tokyo: 156
Nelmes 1951 – In: Reinwardtia: 251
Raym. 1965 – In: Dansk Bot. Ark.: 259
Nelmes 1950: Kew Bull.: 190
C. B. Clarke 1955 – In: Mem. Mus. Hist. Nat. Paris n.s.: 114
C. B. Clarke 1904 – In: J. Linn. Soc. Bot.: 9