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22. Poaceae Tribe ERAGROSTIDEAE
画眉草族 hua mei cao zu
Authors: Shou-liang Chen, Zhen-lan Wu, Sheng-lian Lu, Bi-xing Sun, Sylvia M. Phillips & Paul M. Peterson
Annual or perennial. Leaf blades linear to filiform; ligule a line of hairs, infrequently membranous. Inflorescence a panicle or composed of tough unilateral racemes of biseriate spikelets (bottlebrush in Harpachne); racemes digitate or scattered along an axis or rarely single, persistent or deciduous. Spikelets usually laterally compressed, with one floret or more usually several to many, the uppermost ± reduced, disarticulating below each floret or sometimes by other abscission modes; glumes mostly persistent, usually 1-veined, membranous and shorter than lowest lemma, rarely longer; floret callus sometimes bearded; lemmas membranous to leathery, 1–3-veined (7–11 in Aeluropus), glabrous or hairy, apex entire or 2–3-toothed occasionally with small subsidiary lobes between teeth, mucronate or awned from apex or sinus; palea keels sometimes winged. Stamens 1–3. Fruit sometimes with free pericarp. Leaf anatomy: Kranz PS type; microhairs usually short and stout. x = 10, less often 9, 12.
About 80 genera and 1000 species; tropics and subtropics; 17 genera and 92 species (30 endemic, three introduced) in China.
This tribe is characterized by unspecialized spikelets usually with several florets, 3-veined lemmas, and a rather cartilaginous texture, and also by a ciliate ligule, although there are exceptions to all these characters. This contrasts with the 5-veined lemmas and membranous ligule of most Poeae, which are often superficially similar, especially when the inflorescence is a panicle. Anatomically the two tribes are quite different.
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| 1 |
Spikelets with 1 floret |
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(2) |
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Spikelets with 2 or more florets |
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(4) |
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| 2 (1) |
Ligule membranous; lemma 3-veined, awned; fruit a caryopsis. |
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140 Muhlenbergia |
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Ligule a line of hairs; lemma 1-veined, awnless; fruit with free pericarp |
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(3) |
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| 3 (2) |
Inflorescence an open or spikelike panicle, exserted from uppermost leaf sheath. |
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138 Sporobolus |
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Inflorescence a short dense head, subtended by an inflated leaf sheath with rudimentary blade. |
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139 Crypsis |
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| 4 (1) |
Lemmas 7–11-veined. |
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124 Aeluropus |
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Lemmas 3-veined (subsidiary veins in keel in Eleusine) |
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(5) |
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| 5 (4) |
Lemmas emarginate or 2-toothed at apex, or if entire marginal veins or flanks hairy |
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(6) |
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Lemmas usually entire at apex, glabrous |
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(11) |
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| 6 (5) |
Cleistogamous spikelets concealed within the upper leaf sheaths. |
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126 Cleistogenes |
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Cleistogamous spikelets absent |
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(7) |
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| 7 (6) |
Plants tall, reedlike; inflorescence a large plumose panicle. |
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125 Neyraudia |
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Plants smaller; inflorescence composed of racemes |
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(8) |
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| 8 (7) |
Plants with long scaly rhizomes. |
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127 Orinus |
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Plants lacking long scaly rhizomes |
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(9) |
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| 9 (8) |
Inflorescence a single terminal raceme. |
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128 Tripogon |
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Inflorescence of 2 to many racemes along a central axis |
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(10) |
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| 10 (9) |
Racemes persistent; glumes shorter than lowermost lemma. |
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129 Leptochloa |
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Racemes deciduous; glumes as long as the spikelet. |
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130 Dinebra |
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| 11 (5) |
Inflorescence a panicle. |
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131 Eragrostis |
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Inflorescence of one or more racemes |
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(12) |
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| 12 (11) |
Inflorescence a single terminal raceme |
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(13) |
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Inflorescence of 2 or more racemes |
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(14) |
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| 13 (12) |
Spikelets erect; lemmas disarticulating leaving the persistent paleas. |
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132 Eragrostiella |
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Spikelets deflexed, falling entire with pedicel attached. |
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133 Harpachne |
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| 14 (12) |
Racemes inserted singly, crowded along an elongate central axis; grain smooth. |
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134 Desmostachya |
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Racemes digitate or ± whorled; grain ornamented with a free pericarp |
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(15) |
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| 15 (14) |
Racemes terminating in a sharp point. |
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135 Dactyloctenium |
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Racemes terminating in a fertile or abortive spikelet |
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(16) |
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| 16 (15) |
Racemes terminating in an abortive spikelet; paleas persistent. |
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136 Acrachne |
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Racemes terminating in a fertile spikelet; paleas falling with lemmas. |
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137 Eleusine |
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List of lower taxa
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Treatments in Other Floras @ www.efloras.org
Other Databases
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