Pseudopogonatherum A. Camus
Sometimes referred to Eulalia
Habit, vegetative morphology. Annual, or perennial; caespitose. Culm nodes glabrous. Culm internodes hollow. Leaves mostly basal; non-auriculate. Leaf blades very narrow; without cross venation; persistent; a fringed membrane (short).
Reproductive organization. Plants bisexual, with bisexual spikelets; with hermaphrodite florets. The spikelets homomorphic.
Inflorescence. Inflorescence of spicate main branches (having several spike-like ‘racemes’ on a short axis); open; digitate; espatheate; not comprising ‘partial inflorescences’ and foliar organs. Spikelet-bearing axes ‘racemes’ (shortly pedunculate); persistent (tough, this being the main distinction from Eulalia), or disarticulating (in some forms); when disarticulating, disarticulating at the joints. ‘Articles’ glabrous on the back, with villous-ciliate edges. Spikelets paired; not secund; sessile and pedicellate, or subsessile and pedicellate; consistently in ‘long-and-short’ combinations; in pedicellate/sessile combinations, or unequally pedicellate in each combination. The ‘shorter’ spikelets hermaphrodite. The ‘longer’ spikelets hermaphrodite.
Female-fertile spikelets. Spikelets compressed dorsiventrally; falling with the glumes (falling from the pedicels, or persistent on pedicels and internodes). Rachilla terminated by a female-fertile floret. Hairy callus present. Callus blunt.
Glumes present; two; more or less equal; long relative to the adjacent lemmas; without conspicuous tufts or rows of hairs; awned. Lower glume two-keeled, or not two-keeled; convex on the back, or concave on the back (slightly); not pitted; relatively smooth; 2 nerved. Upper glume 1 nerved. Spikelets with female-fertile florets only (the L1 often absent), or with incomplete florets. The incomplete florets (when present) proximal to the female-fertile florets. The proximal incomplete florets (when present) 1; sterile.
Female-fertile florets 1. Lemmas less firm than the glumes; incised; 2 lobed; deeply cleft (bifid), or not deeply cleft (emarginate); awned. Awns 1; median; from a sinus; geniculate; hairy (villous-ciliate at the edges of the column). Lemmas hairless; non-carinate; 0 nerved. Palea present; nerveless. Lodicules present; 2; free; fleshy; glabrous; toothed, or not toothed. Stamens 3. Anthers not penicillate. Ovary glabrous. Styles free to their bases. Stigmas 2.
Fruit, embryo and seedling. Fruit compressed dorsiventrally to not noticeably compressed. Hilum short. Embryo large.
Abaxial leaf blade epidermis. Costal/intercostal zonation conspicuous. Papillae absent. Long-cells similar in shape costally and intercostally; of similar wall thickness costally and intercostally. Mid-intercostal long-cells rectangular; having markedly sinuous walls. Microhairs present; panicoid-type; (39–)40.5–45 microns long; 6–6.6–7 microns wide at the septum. Microhair total length/width at septum 5.6–6.8. Microhair apical cells 24–26–27 microns long. Microhair apical cell/total length ratio 0.57–0.65. Stomata common; (21–)22.5–25.5(–27) microns long. Subsidiaries triangular. Guard-cells overlapping to flush with the interstomatals. Intercostal short-cells common; not paired (solitary); not silicified. Costal short-cells conspicuously in long rows. Costal silica bodies ‘panicoid-type’; not sharp-pointed.
Transverse section of leaf blade, physiology. C4; XyMS–. Mesophyll with radiate chlorenchyma. Leaf blade ‘nodular’ in section, or adaxially flat. Midrib conspicuous; having a conventional arc of bundles; with colourless mesophyll adaxially (notably between the median bundle and its adaxial strand). Bulliforms present in discrete, regular adaxial groups; in simple fans (these large, occupying most of the epidermis). All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present; forming ‘figures’. Sclerenchyma all associated with vascular bundles.
Cytology. 2n = 40.
Taxonomy. Panicoideae; Andropogonodae; Andropogoneae; Andropogoninae.
Distribution, ecology, phytogeography. 2 species; tropical Asia.
Paleotropical and Australian. Indomalesian. Indo-Chinese, Malesian, and Papuan. North and East Australian. Tropical North and East Australian.
References, etc. Leaf anatomical: this project.
Illustrations. • General aspect. • Abaxial epidermis of leaf blade
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).
