Digitaria acuminatissima Stapf

Gramineae, W. D. Clayton. Flora Zambesiaca 10:3. 1989

Morphology Leaves Leaf sheaths

Leaf sheaths minutely scaberulous, sometimes loosely hairy.

Morphology Leaves Ligules

Ligule up to 2.5 mm. long, truncate to erose.

Morphology Leaves Leaf lamina

Leaf laminae 5–12 × 0.3–0.7 cm., linear, flat, scabrous on both surfaces, with bulbous based bristles near the base, scabrous along the margin.

Morphology Reproductive morphology Inflorescences

Inflorescence composed of (2)5–14 racemes, 12–20 cm. long, erect to patent, 3–5 in a whorl, the superior ones often solitary along a short common axis, sometimes in a second whorl of 2–4 racemes.

Morphology Leaves Rachis

Rhachis triquetrous, broadly winged, up to 0.8 mm. wide, smooth with scabrous margins.

Morphology Reproductive morphology Flowers Pedicel

Pedicels 2-nate, 0.5–3.0 mm. long, triangular, scabrous, scarcely broadened at the apex.

Morphology Reproductive morphology Inflorescences Spikelets

Spikelets 2.8–3.7 mm. long, oblong-lanceolate.

Inferior

Inferior glume oblong triangular, sometimes slightly bifid. Inferior lemma as long as the spikelet, oblong, with a flattened, curved acuminate apex, 7-nerved, appressed hairy, sometimes with a few bulbous based bristles.

Morphology Reproductive morphology Inflorescences Bracts Glume

Superior glume c.1/2 of the spikelet, oblong triangular, 3-nerved, subglabrous to appressed hairy, hairs very fine, white, acute. Inferior glume oblong triangular, sometimes slightly bifid.

Superior

Superior glume c.1/2 of the spikelet, oblong triangular, 3-nerved, subglabrous to appressed hairy, hairs very fine, white, acute. Superior lemma conspicuously shorter than the spikelet, oblong-lanceolate, acuminate, pale yellow to brown.

Morphology Reproductive morphology Inflorescences Bracts Lemma

Superior lemma conspicuously shorter than the spikelet, oblong-lanceolate, acuminate, pale yellow to brown. Inferior lemma as long as the spikelet, oblong, with a flattened, curved acuminate apex, 7-nerved, appressed hairy, sometimes with a few bulbous based bristles.

Morphology General Habit

A creeping annual.

Morphology Culms

Culms 30–80 (100) cm., ascending from a creeping base, glabrous, nodes dark, glabrous.

Morphology General Habit

Annual. Culms decumbent; robust; 60-120 cm long; rooting from lower nodes. Ligule an eciliate membrane. Leaf-blades 3-25 cm long; 3-10 mm wide.

Morphology Reproductive morphology Inflorescences

Inflorescence composed of racemes. Racemes 4-20; digitate, or borne along a central axis; straight; unilateral; 7-25 cm long. Central inflorescence axis 1-10 cm long. Rhachis broadly winged; with sharp-edged midrib. Spikelet packing 0.66 their length apart. Spikelets in pairs. Fertile spikelets pedicelled; 2 in the cluster. Pedicels unequal.

Morphology Reproductive morphology Inflorescences Spikelets

Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate, or elliptic; dorsally compressed; acuminate; 2.5-4 mm long; falling entire.

Fertile

Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate, or elliptic; dorsally compressed; acuminate; 2.5-4 mm long; falling entire.

Morphology Reproductive morphology Inflorescences Bracts Glume

Glumes two; dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.2-0.4 mm long; 0.05-0.1 length of spikelet; hyaline; without keels; 0 -veined. Lower glume lateral veins absent. Lower glume apex obtuse. Upper glume lanceolate; 0.33-0.5 length of spikelet; membranous; without keels; 3 -veined. Upper glume surface pubescent. Upper glume apex acute.

Morphology Reproductive morphology Flowers Florets

Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 1 length of spikelet; membranous; 7 -veined; with equidistant veins; scaberulous; rough on veins; pubescent and setose (sometimes); acuminate. Fertile lemma lanceolate; 2.3-3.5 mm long; cartilaginous; much thinner on margins; pallid, or grey; without keel. Lemma margins flat; covering most of palea. Lemma apex acuminate. Palea cartilaginous.

Distribution

Africa: west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, and south.

Reference

Paniceae. FTEA.

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation

Predicted extinction risk: not threatened. Confidence: confident

IUCN Red List of Threatened Species https://www.iucnredlist.org/species/136642254/136642259

Conservation

LC - least concern

M. Thulin et al. Flora of Somalia, Vol. 1-4 [updated 2008] https://plants.jstor.org/collection/FLOS

Morphology General Habit

Robust annual up to 120 cm high, rooting from the lower nodes; leaves broadly linear

Morphology Reproductive morphology Inflorescences

Inflorescence of 2–4 racemes on an axis (0–)1–10 cm long; racemes stiff, 7–25 cm long, the spikelets in pairs on a winged rhachis with triquetrous midrib

Morphology Reproductive morphology Inflorescences Spikelets

Spikelets narrowly lanceolate to narrowly elliptic, 2.5–4 mm long, acuminate; lower glume an ovate scale up to 0.4 mm long; upper glume 1/3–1/2 the length of the spikelet, 3-nerved; lower lemma 7-nerved, the nerves evenly spaced and scaberulous, obscurely and appressedly pubescent; fruit lanceolate, pallid or grey, 0.2–0.5 mm shorter than the lower lemma.

Distribution

S3 scattered throughout tropical Africa, but nowhere common.

Ecology

Altitude c. 50 m.

Vernacular

Malaaso (Somali)

Note

Similar to the more temperate D. sanguinalis (L.) Scop. but with narrower acuminate spikelets and upper lemma exceeded by the lower.

Gramineae, W. D. Clayton, S. M. Phillips & S. A. Renvoize. Flora of Tropical East Africa. 1974

Morphology General Habit

Annual; culms robust, 60–120 cm. high, rooting at the lower nodes.

Morphology Leaves

Leaf-blades broadly linear, 3–25 cm. long, 3–10 mm. wide.

Morphology Reproductive morphology Inflorescences

Inflorescence of 4–20 racemes on an axis 1–10 cm. long; racemes stiff, 7–25 cm. long, the spikelets binate and overlapping by about 2/3 of their length on a winged rhachis with triquetrous midrib.

Morphology Reproductive morphology Inflorescences Spikelets

Spikelets narrowly lanceolate to narrowly elliptic, 2.5–4 mm. long, acuminate; lower glume a little ovate scale up to 0.4 mm. long; upper glume 1/3–1/2 as long as the spikelet, 3-nerved; lower lemma as long as the spikelet, 7-nerved, the nerves evenly spaced (rarely with a wide interspace flanking the midrib) and scaberulous, obscurely and appressedly pubescent, sometimes with brown glassy bristles; fruit lanceolate, pallid or grey, 0.2–0.5 mm. shorter than the lower lemma.

Habitat

Riversides and damp rocks; 500–900 m.

Distribution

widely spread throughout tropical Africa, but nowhere common T6 T7