DELTA home

The grass genera of the world

L. Watson, T.D. Macfarlane, and M.J. Dallwitz

Pseudodichanthium Bor

Habit, vegetative morphology. Slender annual. Culms 60 cm high. The shoots not aromatic. Leaves non-auriculate. Leaf blades linear (attenuate); narrow; 4–6 mm wide; without cross venation. Ligule an unfringed membrane (?); not truncate (ovate); 1 mm long.

Reproductive organization. Plants bisexual, all with bisexual spikelets; with hermaphrodite florets. The spikelets of sexually distinct forms on the same plant; hermaphrodite and male-only, or hermaphrodite and sterile. The male and female-fertile spikelets mixed in the inflorescence. The spikelets more or less homomorphic; usually in both homogamous and heterogamous combinations (with the basal 2–3 pairs homogamous-sterile).

Inflorescence. Inflorescence of single, terminal and axillary racemes; non-digitate; espatheate (?); not comprising ‘partial inflorescences’ and foliar organs (?). Spikelet-bearing axes ‘racemes’ (curved, 1–1.75 cm long); solitary; with very slender rachides; disarticulating; disarticulating at the joints. ‘Articles’ linear. Spikelets sessile and pedicellate; consistently in ‘long-and-short’ combinations (but the pedicels shorter at the base of the raceme); in pedicellate/sessile combinations. Pedicels of the ‘pedicellate’ spikelets free of the rachis. The ‘shorter’ spikelets hermaphrodite, or sterile (at the base of the raceme). The ‘longer’ spikelets male-only, or sterile.

Female-sterile spikelets. The pedicelled spikelets larger, membranous, winged.

Female-fertile spikelets. Spikelets compressed dorsiventrally. Rachilla terminated by a female-fertile floret. Callus blunt.

Glumes two; long relative to the adjacent lemmas; free; hairless; glabrous; without conspicuous tufts or rows of hairs; awnless; very dissimilar (G1 cartilaginaous, 2-keeled, winged, G2 lanceolate, acute, papery). Lower glume two-keeled (and broadly winged above); broadly convex on the back; not pitted; relatively smooth; 9–11 nerved (7–9 nerved between the keels). Upper glume 3 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; 0 nerved, or 1 nerved; not becoming indurated (hyaline).

Female-fertile florets 1. Lemmas stipitate, passing into the awn; not becoming indurated; entire; not deeply cleft; awned. Awns 1; median; apical; geniculate; hairy. Lemmas without a germination flap. Palea absent. Stamens 3. Ovary apically glabrous. Stigmas 2.

Fruit, embryo and seedling. Fruit small (3 mm long); compressed dorsiventrally.

Classification. Watson & Dallwitz (1994): Panicoideae; Andropogonodae; Andropogoneae; Andropogoninae. Soreng et al. (2015): Panicoideae; Andropogonodae; Andropogoneae; Sorghinae. 1 species (P. serrafalcoides).

Distribution, phytogeography, ecology. Bombay.

Shade species.

Special comments. Fruit data wanting. Anatomical data wanting.

We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, and classifications. See also Guidelines for using data taken from Web publications.

Cite this publication as: ‘Watson, L., Macfarlane, T.D., and Dallwitz, M.J. 1992 onwards. The 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. Version: 11th December 2017.’.