Volume 6 > Part 4 > Year 1998 > Page 379 > Cyperaceae > Cyperus

40. Cyperus compactus Retz.wfo-0000369738

Obs. Bot. 5: 10. 1789; Kük. in Engl., Pflanzenr. 4(20), 101 Heft: 423. 1936; J.Kern, Reinwardtia 6: 63. 1961; in Fl. Males., Ser. 1, Spermat. 7: 638. 1974; Raymond, Dansk Bot. Ark. 23: 354. 1966; Hô, Câyco Viêtnam III. 2: 696. 1993.— Mariscus compactus (Retz.) Bold., Zakfl. Landb. Java 77. 1916; T.Koyama, Gard. Bull. Singapore 30: 153, f. 8. 1977. Fig. 27: A–E. Plate XXVIII: 1–2.

Accepted Name : This is currently accepted.

Synonyms & Citations :

Description : Rhizomatous perennial. Culms 1-few, (30–)50–100 cm by 3–6 mm, trigonous to subterete, septate-nodulose. Leaves: blade linear, up to 100 cm by 5–9(–12) mm, acuminate, canaliculate, septate-nodulose; sheath 10–20 cm long, purplish brown. Involucral bracts 3–5(–8), the longest 60–90 cm long. Inflorescence decompound, 6–30 by 6–30 cm; primary branches 6–12, up to 18 cm long; secondary branches up to 3 cm long. Spikes globose-stellate, 8–20(–35) mm diam.; axis 0.2–0.5 cm long. Spikelets numerous, falling entire, narrowly lanceolate to linear-subulate, subterete, 5–15 by 0.8–1.5 mm; axis zigzag. Glumes 3–7 or rarely more per spikelet, linear-lanceolate to linear-oblong, 3–4.5 by 1–1.5 mm, subobtuse to obtuse, sides membranous, nerves 0, pale brown to reddish brown, slightly shiny, keel 5–7-nerved, greenish to brownish. Stamens 3; anthers 0.8–1 mm long. Stigmas 3. Nutlets narrowly cylindric, trigonous, 1.5–2 by 0.4–0.5 mm, yellowish brown, minutely punctate.

Thailand : NORTHERN: Mae Hong Son (Ban Mae la Noi), Chiang Mai (Doi Suthep, Kongloi, Mae Klang, Omkoi), Chiang Rai, Phayao (Chun), Uttaradit (Sirikit Dam), Phitsanulok (Huai Deua, Sawan Khalok, Thung Salaeng Luang), Kamphaeng Phet, Nakhon Sawan; NORTH-EASTERN: Loei (Phu Kradueng), Udon Thani, Kalasin, Khon Kaen (Chumphae); EASTERN: Chaiyaphum (Chaturat, Tunkamang), Buri Ram; SOUTH-WESTERN: Kanchanaburi (Erawan, Neekey, Pompee, Wang Pra); Phetchaburi (Kaeng Krachan); CENTRAL: Lop Buri (Chai Badan), Phra Nakhon Si Ayutthaya, Saraburi, Nonthaburi, Krung Thep Maha Nakhon (Bangkok); SOUTH-EASTERN: Prachin Buri, Chon Buri (Sattahip, Si Racha), Chanthaburi; PENINSULAR: Chumphon (Tasan), Ranong (Muang Len), Surat Thani (Khao Rahu), Phangnga (Thai Muang), Phuket, Nakhon Si Thammarat (Nabon), Satun (Kuan Po, Ko Tarutao), Songkhla (Hat Yai, Sadao, Ton Plieo), Narathiwat (Waeng).

Distribution : Mascarenes, India (type), Sri Lanka, Indochina, S China, Taiwan, Malesia.

Ecology : Swamps, rice fields, ditches, river banks, wet forests margins and coastal marshes, 0–900 m alt.

Vernacular : Ya bai khom (หญ้าใบคม)(Northeastern).

Notes: A distinct species with star-like globose clusters of spikes, the spike axis up to 0.5 cm long. It is sometimes used for thatch.