Interesting Facts
Description
Genus Digitaria
Annual
or perennial
. Culms
erect
or decumbent
, occasionally stoloniferous
. Leaf blades
linear
or linear-lanceolate; ligule membranous. Inflorescence of digitately arranged racemes
, sometimes on a short axis or with secondary branchlets
, very rarely paniculate
; spikelets
usually in groups of 2-3(-4), imbricate to effuse, the latter often on notably long and unequal pedicels. Spikelets puberulous
to villous
, typically in stripes
between the well-defined veins, rarely glabrous
; lower glume
absent or reduced to a little scale up to 1/4 spikelet length; upper glume variable; lower lemma usually ± equal to spikelet; upper floret pallid
to black, apex subacute
to acuminate, rarely apiculate
. x = 9.
About 250 species:tropical and warm-temperate regions of the world; 22 species (three endemic) in China.
Digitaria has been traditionally divided
on the nature of the spikelet hairs, which may be clavate
, capitate, verrucose
(warty, appearing beaded), or with crooked tips
. As good magnification is required to see these features, the grouping of the spikelets on the raceme is a more practical aid to identification. Many species have regularly paired
spikelets, which present no difficulty. In those species where the spikelets are grouped in clusters
of 3 or more, care must be taken, as often the longest pedicel of a group is partially fused to the rachis so that the spikelets appear alternately paired and single, or sometimes one spikelet may be vestigial, or the spikelets may be paired toward the raceme tips.
Many species are very variable in spikelet pubescence and lemma nervation, even within a single raceme. Additionally, there are a number of complexes of intergrading species, so intermediates may occasionally be encountered. This has led to the publication
of many superfluous names
.[1]
Taxonomy
- Domain:
Eukaryota
(
)
- Whittaker & Margulis,1978
- eukaryotes
- Kingdom:
Plantae
()
- Haeckel, 1866
- Plants
- Subkingdom:
Viridaeplantae
()
- Cavalier-Smith, 1981
- Phylum:
Tracheophyta
()
- Sinnott, 1935 ex Cavalier-Smith, 1998
- Vascular Plants
- Subphylum:
Euphyllophytina
()
- (Auct.) Cavalier-Smith, 1998
- Infraphylum:
Angiospermae
()
- Auct.
- Class:
Spermatopsida
()
- Brongniart, 1843
- Subclass:
Commelinidae
()
- Takhtajan, 1967
- Superorder:
Juncanae
()
- Takhtajan, 1967
- Order:
Poales
()
- Small, 1903
- Family:
Gramineae
()
- A.L. de Jussieu, 1789, nom. cons., nom. alt.
- Subfamily:
Panicoideae
()
- Tribe:
Paniceae
()
- Subtribe:
Digitariinae
()
- Genus:
Digitaria
()
- A. Haller, 1768, nom. cons.
- Crabgrass
- Specific epithet:
ciliaris
- (Fig. & de Not.) R.R.Stewart
- Variety:
chrysoblephara
- Botanical name: - Digitaria ciliaris var. chrysoblephara (Fig. & de Not.) R.R.Stewart (Fig. & de Not.) R.R.Stewart
- Variety:
chrysoblephara
- Specific epithet:
ciliaris
- (Fig. & de Not.) R.R.Stewart
- Genus:
Digitaria
(
- Subtribe:
Digitariinae
(
- Tribe:
Paniceae
(
- Subfamily:
Panicoideae
(
- Family:
Gramineae
(
- Order:
Poales
(
- Superorder:
Juncanae
(
- Subclass:
Commelinidae
(
- Class:
Spermatopsida
(
- Infraphylum:
Angiospermae
(
- Subphylum:
Euphyllophytina
(
- Phylum:
Tracheophyta
(
- Subkingdom:
Viridaeplantae
(
- Kingdom:
Plantae
(
Similar Species
Members of the genus Digitaria
ZipcodeZoo has pages for 53 species, subspecies, varieties, forms, and cultivars in this genus:
D. abyssinica (African Couchgrass) · D. arenicola (Fall Witchgrass) · D. argillacea (Tropical Crabgrass) · D. bicornis (Asia Crabgrass) · D. californica (Arizona Cottontop) · D. ciliaris (Fingergrass) · D. cognata (Carolina Cottontop) · D. cognata var. cognata (Carolina Crabgrass) · D. cognata var. pubiflora (Carolina Crabgrass) · D. cruciata (Crabgrass) · D. diagonalis (Brown-Seeded Finger Grass) · D. didactyla (Crabgrass) · D. dolichophylla (Caribbean Crabgrass) · D. eggersii (Eggers' Crabgrass) · D. eriantha (Pangola Grass) · D. eriantha subsp. eriantha (Crabgrass) · D. eriantha subsp. pentzii (Woolly Fingergrass) · D. exilis (Fonio) · D. filiformis (Slender Crabgrass) · D. floridana (Florida Crabgrass) · D. fuscescens (Yellow Crabgrass) · D. gracillima (Long-Leaf Crabgrass) · D. henryi (Henry´s Crabgrass) · D. hitchcockii (Short-Leaf Crabgrass) · D. horizontalis (Jamaica Crabgrass) · D. iburua (Black Fonio) · D. insularis (Sourgrass) · D. ischaemum (Small Crabgrass) · D. ischaemum var. ischaemum (Small Crabgrass) · D. longiflora (India Crabgrass) · D. milanjiana (Madagascar Crabgrass) · D. natalensis (Natal Crabgrass) · D. nuda (Naked Crabgrass) · D. panicea (Millet Crabgrass) · D. patens (Texas Cottontop) · D. pauciflora (Florida Pineland Crabgrass) · D. pubiflora (Carolina Crabgrass) · D. radicosa (Trailing Crabgrass) · D. sanguinalis (Crabgrass) · D. seriata (Crabgrass) · D. serotina (Blanket Crabgrass) · D. setigera (East Indian Crabgrass) · D. setivalva (Crabgrass) · D. similis (Roadside Crabgrass) · D. simpsonii (Isle-Of-Pines Crabgrass) · D. swalleniana (Swallen's Crabgrass) · D. ternata (Black-Seeded Crabgrass) · D. texana (Texas Crabgrass) · D. tomentosa (Woolly Crabgrass) · D. umfolozi (Crabgrass) · D. velutina (Annual Couchgrass) · D. villosa (Shaggy Crabgrass) · D. violascens (Violet Crabgrass)
More Info
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- Search for Scholarly Articles: Google Scholar
- Search using Scientific Name and Vernacular Names: All the Web | AltaVista Canada | AltaVista | Excite | Google | HotBot | Lycos
- Search using Specialized Databases: GenBank | Medline | Scirus | CISTI/CAL | Agricola Periodicals | Agricola Books
Further Reading
Notes
Contributors
- Brands, S.J. (comp.) 1989-present. The Taxonomicon. Universal Taxonomic Services, Zwaag, The Netherlands. Accessed January 10, 2012.
Identifiers
- Global Biodiversity Information Facility Taxonkey: 16004561
- Globally Unique Identifier: urn:lsid:ipni.org:names:881918-1
- International Plant Names Index (IPNI) ID: 881916-1
- Zipcode Zoo Species Identifier: 3627934
Footnotes
- Shou-liang Chen & Sylvia M. Phillips "Digitaria". in Flora of China Vol. 22 Page 1, 500, 539. Published by Science Press (Beijing) and Missouri Botanical Garden Press. Online at EFloras.org. [back]
