Lorenzochloa J. & C. Reeder
Including Parodiella J. & C. Reeder
Sometimes referred to Ortachne
Habit, vegetative morphology. Perennial; densely caespitose. Culms 15–38 cm high; herbaceous; unbranched above. Leaves mostly basal; non-auriculate. Leaf blades narrow; acicular (erect, rigid, terete, pungent); not pseudopetiolate; without cross venation; persistent; an unfringed membrane; not truncate (acute); 2–4 mm long.
Reproductive organization. Plants bisexual, with bisexual spikelets; with hermaphrodite florets.
Inflorescence. Inflorescence few spikeleted to many spikeleted; paniculate; open (but narrow and rather few flowered, the branches conspicuously pulvinate); espatheate; not comprising ‘partial inflorescences’ and foliar organs. Spikelet-bearing axes persistent. Spikelets not secund; pedicellate.
Female-fertile spikelets. Spikelets 2.3–2.6 mm long; compressed laterally, or not noticeably compressed (?); disarticulating above the glumes. Rachilla terminated by a female-fertile floret. Hairy callus present. Callus short.
Glumes two; more or less equal; shorter than the spikelets; shorter than the adjacent lemmas; hairless; not pointed (truncate or emarginate); awnless; non-carinate; similar (firm). Lower glume 3 nerved. Upper glume 3 nerved. Spikelets with female-fertile florets only; without proximal incomplete florets.
Female-fertile florets 1. Lemmas tapered into the awn; not convolute; without a crown; similar in texture to the glumes; not becoming indurated; entire; pointed; awned. Awns 1; median; apical; non-geniculate; straight, or flexuous (erect or slightly flexuose, stout with a distinct line of demarcation from the rest of the lemma); hairless (scabrous); about as long as the body of the lemma to much longer than the body of the lemma (to 5 mm long). Lemmas hairy (pubescent on the margins and along the lower half of the mid-nerve); non-carinate; without a germination flap; 5 nerved. Palea present; relatively long; prow-tipped, or not prow-tipped (?); awnless, without apical setae; not indurated (firm); 2-nerved; 2-keeled. Palea back hairy (often pubescent between the keels). Palea keels wingless. Lodicules present; 3 (the posterior smaller). Third lodicule present. Lodicules free; membranous (stipoid); glabrous; not toothed; not or scarcely vascularized. Stamens 3. Anthers not penicillate; without an apically prolonged connective. Ovary glabrous. Styles free to their bases. Stigmas 2.
Fruit, embryo and seedling. Fruit small (1.2 to 1.4 mm long); broadly fusiform; compressed dorsiventrally to not noticeably compressed. Hilum long-linear. Embryo small; not waisted; with an epiblast; without a scutellar tail; with a negligible mesocotyl internode. Embryonic leaf margins meeting.
Abaxial leaf blade epidermis. Costal/intercostal zonation lacking. 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 absent. Stomata absent or very rare. Prickles abundant in the silica-cell files. Crown cells absent. Costal short-cells conspicuously in long rows (the rows interrupted only by prickles). Costal silica bodies ‘panicoid-type’; dumb-bell shaped (mostly, short), or cross shaped (a few), or nodular (a few, short); not sharp-pointed.
Transverse section of leaf blade, physiology. C3; XyMS+. Mesophyll with non-radiate chlorenchyma; without adaxial palisade. Leaf blade with distinct, prominent adaxial ribs; with the ribs very irregular in sizes. Midrib not readily distinguishable; with one bundle only. The lamina symmetrical on either side of the midrib. Bulliforms not present in discrete, regular adaxial groups (Ammophila-type groups of small cells in the furrows). All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present; forming ‘figures’ (each main bundle with a large ‘anchor’). Sclerenchyma not all bundle-associated (the feet of the ‘anchors’ joining). The ‘extra’ sclerenchyma in a continuous abaxial layer.
Cytology. Chromosome base number, x = 11. 2n = 22. 2 ploid.
Taxonomy. Stipoideae; Stipeae.
Distribution, ecology, phytogeography. 1 species; High Andes of Venezuela, Colombia, Peru.
Neotropical. Caribbean.
References, etc. Leaf anatomical: this project.
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).