Family: Poaceae |
Plants cespitose, annual or perennial, sometimes rhizomatous. Culms (3-)10-300 cm tall, round or somewhat compressed, usually ascending to erect, often geniculate at the lower nodes, rarely decumbent and rooting at the nodes, sometimes highly highly reduced and prostrate, often branching above the base; nodes glabrous; internodes hollow or with stellate arenchyma; leaves cauline; sheaths open, longer or shorter than internodes; ligules 1–8(–15) mm long, membranous or hyaline, acute to attenuate, becoming lacerate in age; blades flat, often becoming involute when dry, midribs prominent on the upper surfaces. Inflorescences panicles with numerous spikelke branches, these usually alternate on an elongate central axis, varying to subwhorled or whorled; branches usually ascending, widespread to reflexed in one species, stiff, minutely scabrous, usually 1-sided with spikelets in 2 rows, terminating in a functional spikelet. Spikelets with (2–)3–12(–20) florets, well separated to overlapping, usually rounded to somewhat compressed, becoming more rounded or flattened at maturity, green to lead-colored; calluses glabrous; florets usually bisexual, occasionally unisexual; rachillas rarely prolonged. Glumes unequal, membranous, 1-veined; lemmas 3-veined, acute, obtuse or emarginate, unawned, glabrous or veins sericeous, especially at base, lateral veins distinct, occasionally excurrent; paleas membranous, usually subequal to the lemmas; stamens usually 3, sometimes 1 or 2; anthers 0.2-2.7 mm long, yellow or maroon. Caryopses dorsally compressed, elliptic to narrowly elliptic in hilar profile. n=10; 2n=19, 20. Diplachne has three species, Diplachne fusca grows in tropical and temperate regions of both the Old and New World; Diplachne gigantea is restricted to tropical Africa, and Diplachne divaricatissima to eastern Australia Plants tufted perenials,sometimes aquatic or semi-aquatic an rooting and branching from the lower nodes, to 1.5 m tall. Leaves: ligules membranous or hyaline, becoming lacerate with age. Inflorescences panicles with numerous spikelike branches on an elongated central axis, terminating in a functional spikelet. Spikelets with 7-12 flowers, subterete; glumes unequal, 1-veined; lemmas rounded on the back, 3-veined, veins pilose on their lower portions, tips mucronate. Caryopses dorsally compressed. Diplachne now includes three species. One, Diplachne fusca, is known from Somalia. None were reported from Somaliand in the Flora of Somalia. Given that Diplachne fusca is an aquatic or semiaquatic species, its absence from Somaliland is not surprising. Peterson, P.M., K. Romaschenko, N. Snow, & G. Johnson (2012) A molecular phylogeny of Leptochloa (Poaceae: Chloridoideae: Chlorideae). Ann. Bot. 109: 1317–1329. Snow, N. & P.M. Peterson (2012) Nomenclatural notes on Dinebra, Diplachne, Disakisperma, and Leptochloa (Poaceae: Chlorioideae). Phytoneuron 2012-71:1-2. ISSN 2153 733X. Snow, N., P.M. Peterson, K. Romaschenko (2013) Systematics of Disakisperma (Poaceae, Chloridoideae, Chlorideae). PhytoKeys 26: 21–70. doi: 10.3897/phytokeys.26.5649 Snow, N., P.M. Peterson, K. Romaschenko, B.K. Simon (2018) Monograph of Diplachne (Poaceae, Chloridoideae, Cynodonteae). PhytoKeys 93: 1-102. https://doi.org/10.3897/phytokeys.93.21079 Global distribution of Diplachne. Note: GBIF records include introduced and cultivated plants. Consequently, the distribution shown often differs from statements about a taxon's native distribution. |