Ischaemum 鴨嘴草屬
型態特徵
Annuals or perennials; culms solid. Leaf blade lanceolate or linear, sometimes with a pseudo-petiole. Inflorescence of 2 to several spike-like racemes, more or less digitately arranged, if only 2 racemes present, then usually closely appressed, at first sight appearing as a single racme. Spikelets dorsally compressed, 2-flowered, sometimes 1-flowered, in alternate pairs, one sessile, other pedicelate. Pedicelate spikelet falling entire from pedicel, callus blunt, or usually stipe-like and bearded. Spikelets sessile, arranged in front, all pedicelate spikelets behind, sometimes pedicels very short; lower glume oblong or lanceolate, convex, often hardened in lower half, often tuberculate or transversely rugose, often winged towards apex; entire or a 2-lobed, numerous-nerved, nerves of hardened lower glume only distinct near top, margins inrolled or inflexed; upper glume narrower, often longer, boat shaped, often keeled, acute, muticous or with short awn; lower lemma shorter than lower glume, ovate-oblong, apex narrowed, thinly membranaceous; lower palea nearly as long, oblong; stamens 3, or reduced into staminodes; upper lemma well-developed, convex, hyaline, entire or 2-fid and awned from sinus, awn short or long, nerves 3-5 upper palea 2-nerved; stamens 3; styles 2, free, stigmas plumose. Caryopsis oblong.
About 50 species in the tropics and subtropics regions; nine species, one variety and two forms in Taiwan.
種列表
- Ischaemum akonense 屏東鴨嘴草
- Ischaemum anthephoroides 毛鴨嘴草
- Ischaemum aristatum 芒穗鴨嘴草
- Ischaemum aristatum var. momiyamai 毛穗鴨嘴草
- Ischaemum aureum 黃金鴨嘴草
- Ischaemum barbatum var. gibbum 瘤鴨嘴草
- Ischaemum barbatum var. gibbum f. nodulosum 毛瘤鴨嘴草
- Ischaemum crassipes 鴨嘴草
- Ischaemum guianense
- Ischaemum hondae
- Ischaemum imbricatum 粗毛鴨嘴草
- Ischaemum indicum 印度鴨嘴草
- Ischaemum intermedium
- Ischaemum longisetum
- Ischaemum muticum 無芒鴨嘴草
- Ischaemum nodulosum
- Ischaemum polystachyum
- Ischaemum rugosum var. segetum 田間鴨嘴草
- Ischaemum rugosum f. akoense
- Ischaemum setaceum 小黃金鴨嘴草
- Ischaemum sp.
- Ischaemum timorense 帝汶鴨嘴草
