Belongs within: Zoysieae.
Sporobolus, dropseeds, is a genus of grasses named for the manner in which the seeds are easily shed. The genus as historically defined is paraphyletic and may be expanded to cover genera such as Spartina (Kellogg 2015).
Characters (Hickman 1993): Annual or perennial. Stems generally ascending to erect, 2–20 dm, generally tufted, more or less solid in cross-section. Leaves generally basal; cauline few, ascending or curving away; distal sheath margin and collar glabrous or hairy; ligule less than 1 mm, hairy or membranous, fringed; blade flat to inrolled, generally glabrous or scabrous, sometimes short-soft-hairy. Inflorescence terminal, also sometimes axillary, panicle- or spike-like, generally partly enclosed by sheath; branches spreading or appressed. Spikelet less than 6 mm, generally pale to gray-green or purplish; glumes generally unequal, upper shorter or longer than lemma, membranous to translucent, one-veined; floret bisexual, generally breaking above glumes; lemma texture generally like glumes, 1(3)-veined; palea shorter or longer than lemma. Fruit 1–3 mm, generally falling from floret, generally gelatinous when wet.
<==Sporobolus Br. 1810 [Sporoboleae]K15
|--S. actinocladus (Muell.) Muell. 1874G52 [=Agrostis actinocladaB78, Vilfa actinocladaB78]
|--S. africanusP82
|--S. airoides [incl. S. airoides var. wrightii]H93
|--S. argutus (Nees) Kunth. 1833 [=Vilfa arguta Nees 1829; incl. S. coromandelianus, S. sprengelii]S06
|--S. asperV72
|--S. asperifolius (see below for synonymy)S06
|--S. australasicus Domin 1911G52
|--S. blakeiLK14
|--S. brasiliensisS06
|--S. capensisG52 [=Agrostis capensisG52, Vilfa capensisB78; incl. Sporobolus tenacissimusB78, V. tenacissimaB78]
|--S. caroli Mez 1921G52
|--S. contractusH93
|--S. cryptandrusRJ11
|--S. diander [=Agrostis diandra, Vilfa diandra; incl. V. erosa]B78
|--S. flexuosusBTA75
|--S. giganteusGPWG01
|--S. helvolusPP07
|--S. heterolepisB75
|--S. hintoniiS57
|--S. indicusGPWG01 [incl. S. elongatusC06, Vilfa elongataB78]
| |--S. c. var. capensisS03
| `--S. ‘indicus’ var. purpureosuffususS03
|--S. ligularis Hackel 1902S06
|--S. lindleyi [=Vilfa lindleyi; incl. S. subtilis]B78
|--S. littoralisC55
|--S. minutiflorusC55
|--S. mitchellii (Trin.) Hubb. 1941 [=Vilfa mitchellii; incl. S. benthamii]G52
|--S. nealleyiiHW96
|--S. nebulosusCV06
|--S. neglectus [=S. vaginiflorus var. neglectus]V72
|--S. phleoides Hackel in Stuckert 1906S06
|--S. pulchellus [=Vilfa pulchella]B78
|--S. spicataBB01 [=Vilfa spicataD17]
|--S. stapfianusK15
|--S. tenuissimusPP07
|--S. texanusHW96
|--S. tuberculatus Hackel in Stuckert 1906S06
|--S. vaginiflorusH93
| |--S. v. var. vaginiflorusV72
| `--S. v. var. inaequalisV72
|--S. virginicus (L.) Kunth 1832G52 [=Agrostis virginicaB78, Vilfa virginicaB78]
| |--S. v. var. virginicusB78
| `--S. v. var. pallidaB78
|--S. viscidus Sohns 1957S57
`--S. wallichi Munro ex von Trinius 1889SY02
Sporobolus asperifolius [=Vilfa asperifolius Nees & Meyen 1840; incl. Agrostis distichophylla Philippi 1860, Sporobolus distichophyllus (Philippi) Philippi 1897, A. eremophila (Philippi) Spegazzini 1902, S. sarmentosus Grisebach 1879]S06
*Type species of generic name indicated
References
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