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41 (2015)
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Table 3 Key to species of Oryza in Thailand.
1. Sterile lemma more than half the length of the spikelet
3. O. ridleyi
1. Sterile lemma less than half the length of the spikelet
2. Ligule up to 5 mm long
3. Fertile lemma and palea with an irregularly granular surface
1. O. meyeriana
3. Fertile lemma and palea with a regularly granular surface
2. O. minuta
2. Ligule more than 5 mm long
4. Spikelets disarticulating; lemma and palea usually with purplish or dark red spots at
the apex; fertile lemma long-awned; wild
4. O. rufipogon
4. Spikelets persistent; lemma and palea without purplish or dark red spots at the apex;
fertile lemma acute, cuspidate or acuminate, awnless; cultivated
5. O. sativa
linear to lanceolate; fertile lemma boat-shaped, lin-
ear, elliptic, oblong-ovate or lanceolate, coriaceous.
Palea
smaller than lemma but similar in texture.
Caryopsis
terete.
A genus of 20 species in tropical and subtropical
regions
13
; five species and one variety occur in Thai-
land, including O. sativa, a cultivated plant known
throughout the range of the genus. See
Table 3
.
1.
Oryza meyeriana
(Zoll. & Moritzi) Baill., Hist.
Pl. 12:
166. 1893.— Padia meyeriana Zoll. &
Moritzi, Syst. Verz. 103. 1846. Type: Java, near
Cibodas, 27 Nov. 1842, Zollinger 718 (holotype n.v.;
isotypes BM!, G, K!, 2 sheets, L!, LE, P!, US). See
Table 4
.
a.
O. meyeriana
var. meyeriana
Fig. 1
E,F,
Fig. 5
.
Perennial, loosely tufted or shortly stoloniferous
herb.
Culms
up to 60 cm tall, erect or ascend-
ing, sometimes branching at base; nodes terete,
glabrous. Leaf-sheath slightly loose, glabrous, au-
ricles well defined, ciliate; ligules 0.8–1.2 mm
long; leaf-blades (1.2–)2–3.5
× 7–26 cm, lanceolate-
acute, rarely linear-lanceolate, margins scabrous,
scabrid along nerves on both sides.
Inflores-
cence
panicle, narrowly contracted, erect. Spikelets
1(–3)
× (6–)6.5–8 mm, lanceolate to linear-lance-
olate, light green, pale yellow or sometimes
yellowish-brown. Glumes c. 0.5–0.8 mm long, cup-
shaped; sterile lemma 1–2.5 mm long, less than
half the length of the spikelet, narrowly lanceo-
late to lanceolate; fertile lemma 1.8–2
× (6–)6.5–
Table 4 Key to the varieties of
O. meyeriana.
1. Leaves lanceolate, rarely linear-lanceolate;
spikelet 1(–3)
× (6–)6.5–8 mm, lanceolate
to linear-lanceolate
a. var. meyeriana
1. Leaves linear to linear-lanceolate, rarely
lanceolate; spikelet 2(–3)
× 5–6(–6.5) mm,
oblong-elliptic
b. var. granulata
Fig. 5
Oryza meyeriana
(Zoll. & Moritzi) Baill. var.
meyeriana
: (a) habit; (b) lemma; (c,d) palea; (e) apex of
palea; (f) lodicules; (g) pistil. Drawn by M. Norsaengsri.
7.5 mm, lanceolate, boat-shaped, coriaceous, irreg-
ularly granular surface, awnless. Palea c. 1.8
× 6.5–
7.5 mm, smaller and narrower than the lemma,
similar in texture and surface, linear to linear-
lanceolate.
Thailand.— SOUTH-WESTERN: Prachuap Khiri
Khan, Bang Sapan, 20 Aug. 1967, T. Shimizu
& A. Nalampoon T7771
(AAU); PENINSULAR:
Chumphon, Ta Ngaw, 22 Jan. 1927, Kerr 11600
(K); Panom, 24 Mar. 1927, Kerr 12412 (K); Surat
Thani, Bangbao, 7 Aug. 1955, T. Smitinand 2841
(BKF, K); Phatthalung, See Bahn Pote, Kao Boo-Kao
Yah National Park, near Mat Cha cave, 15 Jun. 1986,
J.F. Maxwell 86-387
(L); Khao Phu Khao Ya National
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370
ScienceAsia
41 (2015)
Park, 31 Mar. 2012, Sumanon & Traiperm 1 (BKF);
Trang, Kantang, 31 May 1919, Md. Haniff & Nur
4712
(K); Satun, Boripath waterfall, 19 Oct. 1991,
K. Larsen, S.S. Larsen, C. Niyomdham, W. Ueachi-
rakan & P. Sirirugsa 42393
(AAU); Songkhla, Rat-
taphum, 16 Oct. 1984, J.F. Maxwell 84-329 (BKF).
Distribution.— Malaysia and Thailand.
Habitat and Ecology.— Occurring in shaded and
semi-shaded areas along streams, among rocks and
in wet soil, from sea level to 200 m elevation.
Flowering from January until October.
Conservation assessment.— Nine locations
were confirmed for this species in Thailand, all in
the peninsular region, giving an EOO of 54 416 km
2
and an AOO of 36 km
2
. The subpopulations are
small and scattered. This variety is not thought to
have undergone decline, nor is it facing any specific
threat at present. We assess it as LC in Thailand.
Notes.— In Thailand, this variety has only been
found in the peninsular region.
b.
O. meyeriana
var. granulata (Nees & Arn. ex G.
Watt) Duist., Blumea. 32: 1. 1987.— O. granulata
Nees & Arn. ex G. Watt, Dict. Econ. Prod. India 5:
500. 1891. Type: India, Herb. Wight 2354 (holotype
B destroyed; lectotype K!, designated here; isolec-
totypes K!, K-W!, P!, U!).— O. meyeriana subsp.
granulata
(Nees & Arn. ex G. Watt) Tateoka, Bot.
Mag. Tokyo 75: 460. 1962, f. 3a.
Fig. 6
,
Fig. 7
A,B.
Perennial, loosely tufted or shortly stoloniferous
herb.
Culms
up to 80 cm tall, erect or ascend-
ing, sometimes branching at base; nodes terete,
glabrous. Leaf-sheath slightly loose, glabrous, au-
ricles well defined, ciliate; ligules 0.8–1.2 mm
long;
leaf-blades
0.8–2.8
× 7–22 cm, linear to
linear-lanceolate, acute, rarely lanceolate, mar-
gins scabrous, scabrid along nerves on both sides.
Inflorescence
panicle, narrowly contracted, erect.
Spikelets
2(–3)
× 5–6(–6.5) mm, oblong-elliptic,
light green or sometimes yellowish-brown. Glumes
c. 0.5 mm long, cup-shaped; sterile lemma c. 0.5 mm
long, less than a half length of the spikelet, narrowly
lanceolate to lanceolate; fertile lemma 1.8–2
× 4.5–
5.5(–6) mm, elliptic to oblong-ovate, boat-shaped,
coriaceous, irregularly granular surface, awnless.
Palea
c. 1.5
× 4.5–5.5 mm, similar in texture and
surface to the lemma, linear-lanceolate.
Thailand.— NORTHERN: Mae Hong Son, Mae
Sariang, 12 Jul. 1968, K. Larsen, T. Santisuk & E.
Warncke 2382
(AAU, K, L); Chiang Mai, Doi Sutep,
6 Jul. 1910, Kerr 1241 (K); Wang Tao, 11 Jul. 1958,
Th. Sørensen, K. Larsen & B. Hansen 3980
(C, K);
Sa Moeng, 13 Sep. 1958,
Th. Sørensen, K. Larsen &
Fig. 6
Oryza meyeriana
(Zoll. & Moritzi) Baill. var.
granulata
(Nees & Arn. ex G. Watt) Duist.: (a) habit;
(b) spikelet; (c) lodicules, stamens, and pistils; (d) cary-
opsis. Drawn by M. Norsaengsri.
B. Hansen 4960
(C); Lampang, Ngao, 26 May 1954,
T. Smitinand 1614
(K); NORTH-EASTERN: Nakhon
Phanom, Dan Tan, 15 May 1932, Kerr 21464 (BK,
K); SOUTH-WESTERN: Kanchanaburi, Sai Yok, 31
Jul. 1918, A. Marcan 2356 (K); Hin Dat, 5 Jul. 1926,
Put 86
(BK, K); Sai Yok, 31 Jul. 1928, Put 1791
(BK, K); Ta Salao, 11 Jul. 1930, Kerr 19 521 (BK, K);
Wangka, 29 Apr. 1946, G. den Hoed 240 (BK, K, L);
Sai Yok, 1 Jul. 1963, K. Larsen 10 384 (C, K), 10 484
(C, K); Sai Yok, 4 Dec. 1961, K. Larsen 8496 (C,
K); Huay Bankau, 9 Nov. 1971, C.F. van Beusekom,
C. Phengkhlai, R. Geesink & B. Wongwan 3604
(K);
SOUTH-EASTERN: Chanthaburi, Pong Nam Ron, 28
Nov. 1956, T. Smitinand 3652 (K); Soi Dao, 7 Jun.
1963, K. Larsen 9834 (C, K).
Distribution.— Also occurring in China, Myan-
mar, Laos, Cambodia, Malaysia, and Indonesia.
Habitat and Ecology.— Growing in moist areas
in evergreen and deciduous forests, and in bamboo
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