Hemisorghum C.E. Hubb.
Habit, vegetative morphology. Stout perennial; caespitose. Culms herbaceous. Culm internodes solid. Leaf blades linear-lanceolate; broad; flat; a fringed membrane (?).
Reproductive organization. Plants bisexual, with bisexual spikelets; with hermaphrodite florets. The spikelets of sexually distinct forms on the same plant; hermaphrodite and sterile; overtly heteromorphic (the pedicelled smaller, lacking the L1); all in heterogamous combinations.
Inflorescence. Inflorescence paniculate (a large decompound panicle with whorled, triquetrous or angular, scabrid branches); open; non-digitate; espatheate; not comprising ‘partial inflorescences’ and foliar organs (?). Spikelet-bearing axes ‘racemes’ (few to several-noded); solitary; with very slender rachides; disarticulating; disarticulating at the joints. ‘Articles’ linear (slender); not appendaged; disarticulating transversely. Spikelets paired; consistently in ‘long-and-short’ combinations; in pedicellate/sessile combinations. Pedicels of the ‘pedicellate’ spikelets free of the rachis. The ‘shorter’ spikelets hermaphrodite. The ‘longer’ spikelets sterile.
Female-sterile spikelets. The sterile pedicelled spikelets without an L1.
Female-fertile spikelets. Spikelets compressed dorsiventrally (?); falling with the glumes (falling with the joint and the pedicelled spikelet). Rachilla terminated by a female-fertile floret. Hairy callus present (with a ring of minute hairs). Callus short; blunt.
Glumes two; more or less equal; long relative to the adjacent lemmas; G2 with ciliate margins; awnless; very dissimilar (leathery, the G1 obtuse, dorsally flat or slightly convex, 2-keeled for most of its length with the margins inflexed towards the base, the G2 lanceolate, acute, dorsally rounded, becoming 1-keeled upwards). Lower glume two-keeled; convex on the back to flattened on the back; not pitted; relatively smooth; 8–11 nerved. Upper glume 7 nerved. Spikelets with incomplete florets. The incomplete florets proximal to the female-fertile florets. Spikelets with proximal incomplete florets. The proximal incomplete florets 1; sterile. The proximal lemmas awnless; 2 nerved; more or less equalling the female-fertile lemmas to decidedly exceeding the female-fertile lemmas; similar in texture to the female-fertile lemmas (thinly membranous to hyaline); not becoming indurated.
Female-fertile florets 1. Lemmas less firm than the glumes (thin); not becoming indurated; incised; minutely 2 lobed; not deeply cleft (minutely bidentate); awnless, or mucronate (between the teeth); ciliolate; non-carinate; without a germination flap; 1 nerved. Palea present; relatively long (about as long as the lemma); linear oblong; awnless, without apical setae; textured like the lemma; not indurated; nerveless; keel-less. Lodicules present; 2; free; fleshy; glabrous. Stamens 3. Ovary glabrous. Styles fused (at base). Stigmas 2; red pigmented.
Fruit, embryo and seedling. Fruit compressed dorsiventrally (plano-convex). Hilum short. Embryo large.
Taxonomy. Panicoideae; Andropogonodae; Andropogoneae; Andropogoninae.
Distribution, ecology, phytogeography. 2 species; India, Burma, Southeast Asia. On hillsides and riverbanks.
Paleotropical. Indomalesian. Indo-Chinese.
Special comments. Anatomical data wanting.
Cite this publication as: Watson, L., and Dallwitz, M. J. (1992 onwards). ‘Grass Genera of the World: Descriptions, Illustrations, Identification, and Information Retrieval; including Synonyms, Morphology, Anatomy, Physiology, Phytochemistry, Cytology, Classification, Pathogens, World and Local Distribution, and References.’ http://biodiversity.uno.edu/delta/. Version: 18th August 1999. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993 onwards, 1998), and Watson and Dallwitz (1994), and Watson, Dallwitz, and Johnston (1986) should also be cited (see References).