Dichanthelium portoricense |
Dichanthelium portoricense subsp. portoricense |
|||||
---|---|---|---|---|---|---|
blunt-glumed panicgrass |
||||||
Habit | Plants usually densely cespitose. | |||||
Culms | 15-50 cm, slender, wiry; internodes olive green to purplish, densely puberulent or glabrous; fall phase spreading or decumbent, branching extensively from the lower and midculm nodes, producing numerous congested fascicles of reduced, flat or involute blades and reduced secondary panicles. |
15-40 cm, glabrous or puberulent. |
||||
Sheaths | glabrous or puberulent; cauline blades 2-5 cm long, 2.5-4.5 mm wide, usually puberulent abaxially and glabrous adaxially. |
|||||
Cauline leaves | 4-7; sheaths much shorter than the internodes, densely crisp-puberulent, velvety-puberulent, or glabrous, often ciliate along the margins; ligules shorter than 0.5 mm; blades 2-7 cm long (seldom longer), 2.5-8 mm wide (rarely wider), spreading, firm, flat or slightly involute, without prominently raised veins, not longitudinally wrinkled, densely puberulent or glabrous abaxially, glabrous, sparsely puberulent, or pubescent adaxially, bases subcordate, with papillose-based cilia, margins often whitish and scabridulous. |
|||||
Spikelets | 1.5-2.6 mm, obovoid-pyriform, planoconvex in side view, puberulent, pubescent, or glabrous, attenuate basally, apices usually broadly rounded. |
1.5-2.0 mm, puberulent to nearly glabrous. |
||||
Lower glumes | 0.6-1.4 mm, thin, weakly-veined, attached about 0.2 mm below the upper glumes, clasping at the base; upper glumes as long as or slightly shorter than the lower lemmas; upper florets 1.4-2 mm, broadly ellipsoid, apices subacute, minutely puberulent. |
|||||
Basal | rosettes well-differentiated; blades 1.5-6 cm, ovate to lanceolate. |
|||||
Primary | panicles 2-7 cm long, 2/3 to nearly as wide as long, with relatively few spikelets, exserted; branches flexuous, spreading or reflexed, scabridulous to densely puberulent. |
panicles 2-4.5 cm. |
||||
2n | = 18. |
|||||
Dichanthelium portoricense |
Dichanthelium portoricense subsp. portoricense |
|||||
Distribution | ||||||
Discussion | Dichanthelium portoricense grows in sandy woods, low pinelands, savannahs, and coastal sand dunes, usually in moist places. Its range extends south from the Flora region into Mexico, the Caribbean, and Mesoamerica. It is a highly variable species with numerous intergrading forms, some possibly resulting from hybridization with other widespread species in the same region, such as D. sphaerocarpon and D. commutatum. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Dichanthelium portoricense subsp. portoricense is more common than subsp. patulum in coastal sand dunes. It also grows in sandy pinelands and savannahs. It resembles D. aciculare somewhat, but that species usually has ascending-pilose culms, strongly involute or acicular blades, and longer spikelets. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
||||
Key |
|
|||||
Source | FNA vol. 25, p. 441. | FNA vol. 25, p. 442. | ||||
Parent taxa | Poaceae > subfam. Panicoideae > tribe Paniceae > Dichanthelium > sect. Lancearia | Poaceae > subfam. Panicoideae > tribe Paniceae > Dichanthelium > sect. Lancearia > Dichanthelium portoricense | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Panicum portoricense | |||||
Name authority | (Desv. ex Ham.) B.E Hansen & Wunderlin | unknown | ||||
Web links |