Leptochloöpsis Yates
Sometimes referred to Uniola (U. condensata and U. virgata)
Habit, vegetative morphology. Perennial (robust); caespitose. Culms 100–200 cm high; herbaceous. Plants unarmed. Leaf blades attenuated from about 8 mm wide; narrow; flat, or rolled (involute); without abaxial multicellular glands; without cross venation.
Reproductive organization. Plants bisexual, with bisexual spikelets; with hermaphrodite florets.
Inflorescence. Inflorescence of spicate main branches; contracted (the stiff branches narrowly ascending). Primary inflorescence branches numerous. Inflorescence espatheate; not comprising ‘partial inflorescences’ and foliar organs. Spikelet-bearing axes slender; persistent. Spikelets secund (conspicuously on one side of the rachis, usually closely imbricate); biseriate; shortly pedicellate; imbricate.
Female-fertile spikelets. Spikelets 1.5–7 mm long; oblong, or elliptic; compressed laterally; falling with the glumes; not disarticulating between the florets. Rachilla prolonged beyond the uppermost female-fertile floret.
Glumes present; two; very unequal (the upper longer); shorter than the adjacent lemmas; hairless; pointed (acuminate); awnless; carinate; similar. Spikelets with incomplete florets. The incomplete florets proximal to the female-fertile florets, or both distal and proximal to the female-fertile florets (?). Spikelets with proximal incomplete florets. The proximal incomplete florets 1–3 (?); sterile. The proximal lemmas awnless; 5 nerved; exceeded by the female-fertile lemmas; similar in texture to the female-fertile lemmas.
Female-fertile florets 3–6. Lemmas acuminate; not becoming indurated (firm, smooth, shining); entire; pointed; awnless, or mucronate (?); carinate (compressed-keeled, especially above); 5 nerved. Palea present; awnless, without apical setae. Lodicules present; free; fleshy; glabrous. Stamens 3. Stigmas 2.
Fruit, embryo and seedling. Fruit longitudinally grooved, or not grooved; not noticeably compressed, or trigonous. Hilum short. Pericarp fused (?). Embryo large; with an epiblast; with a scutellar tail; with an elongated mesocotyl internode. Embryonic leaf margins meeting.
First seedling leaf with a well-developed lamina. The lamina narrow; erect to curved.
Abaxial leaf blade epidermis. Costal/intercostal zonation conspicuous (but obviously distinguished only by the distribution of stomatal bands). 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 (but scarce, and no good examples seen); chloridoid-type (?). Stomata common; 24–27 microns long. Subsidiaries low dome-shaped. Intercostal short-cells common; in cork/silica-cell pairs (some solitary); silicified. Intercostal silica bodies absent; rounded and crescentic. Costal short-cells predominantly paired (some solitary). Costal silica bodies present throughout the costal zones; rounded, or saddle shaped (or rectangular), or crescentic; not sharp-pointed.
Transverse section of leaf blade, physiology. Lamina mid-zone in transverse section open.
C4; XyMS+. PCR sheaths of the primary vascular bundles interrupted; interrupted both abaxially and adaxially. PCR sheath extensions present. Maximum number of extension cells 6–10. PCR cells with a suberised lamella, or without a suberised lamella. Mesophyll traversed by columns of colourless mesophyll cells (connected to abaxial sclerenchyma groups). Leaf blade with distinct, prominent adaxial ribs. Bulliforms present in discrete, regular adaxial groups; associated with colourless mesophyll cells to form deeply-penetrating fans (these linked with traversing columns of colourless cells). All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present; forming ‘figures’ (in the large bundles). Sclerenchyma not all bundle-associated. The ‘extra’ sclerenchyma in abaxial groups; abaxial-hypodermal, the groups isolated, or abaxial-hypodermal, the groups continuous with colourless columns.
Cytology. Chromosome base number, x = 10 (n = 20). 2n = 40.
Taxonomy. Chloridoideae; main chloridoid assemblage.
Distribution, ecology, phytogeography. 2 species; Puerto Rico and South to Central America. Xerophytic; species of open habitats; halophytic, or glycophytic.
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).