Calamovilfa Hackel
From the Greek kalamos (a reed) and Vilfa, a grass generic synonym.
Habit, vegetative morphology. Coarse perennial; rhizomatous, or caespitose (with short thick rhizomes). Culms 50–200 cm high; herbaceous; unbranched above. Culm internodes solid. Leaves not basally aggregated; non-auriculate. Leaf blades narrow; rolled (firm); without abaxial multicellular glands; rolled in bud; a fringe of hairs.
Reproductive organization. Plants bisexual, with bisexual spikelets; with hermaphrodite florets.
Inflorescence. Inflorescence paniculate; open, or contracted; when contracted, spicate to more or less irregular; espatheate; not comprising ‘partial inflorescences’ and foliar organs. Spikelet-bearing axes persistent. Spikelets not secund; pedicellate.
Female-fertile spikelets. Spikelets 5–9 mm long; lanceolate; compressed laterally; disarticulating above the glumes. Rachilla terminated by a female-fertile floret. Hairy callus present (the hairs sometimes longer than half lemma length).
Glumes two; very unequal; shorter than the spikelets to about equalling the spikelets; shorter than the adjacent lemmas, or long relative to the adjacent lemmas; pointed (acute); awnless; carinate; similar (papery or membranous). Lower glume 1 nerved. Upper glume 1 nerved. Spikelets with female-fertile florets only; without proximal incomplete florets.
Female-fertile florets 1 (rarely with a second). Lemmas similar in texture to the glumes; not becoming indurated; entire; pointed; awnless; hairy (pilose at base), or hairless; carinate (slightly), or non-carinate; 1 nerved. Palea present; relatively long; 2-nerved; 2-keeled. Lodicules present; 2; free; fleshy; glabrous; heavily vascularized. Stamens 3. Anthers 3–5.5 mm long. Ovary glabrous. Stigmas 2.
Fruit, embryo and seedling. Fruit linear, or ellipsoid. Hilum short. Pericarp free. Endosperm hard; without lipid. Embryo with an epiblast; with a scutellar tail; with an elongated mesocotyl internode. Embryonic leaf margins meeting.
Abaxial leaf blade epidermis. Costal/intercostal zonation conspicuous. Papillae absent. Long-cells markedly different in shape costally and intercostally (the costals narrower, more regularly rectangular); of similar wall thickness costally and intercostally (the walls thick), or differing markedly in wall thickness costally and intercostally (the costals thicker walled). Mid-intercostal long-cells having markedly sinuous walls (heavily pitted). Microhairs present; elongated; clearly two-celled; chloridoid-type (with long basal cells). Microhair apical cell wall of similar thickness/rigidity to that of the basal cell. Microhairs 38–48(–60) microns long. Microhair basal cells 45 microns long. Microhairs 9.6–11.4 microns wide at the septum. Microhair total length/width at septum 3.9–5. Microhair apical cells 7–10(–12) microns long. Microhair apical cell/total length ratio 0.15–0.2. Stomata common; 22.5–30 microns long. Subsidiaries triangular, or dome-shaped (mostly, in C. longifolia). Guard-cells overlapping to flush with the interstomatals. Intercostal short-cells common; in cork/silica-cell pairs and not paired (some solitary); silicified. Intercostal silica bodies absent, or imperfectly developed; mostly saddle shaped. Costal short-cells neither distinctly grouped into long rows nor predominantly paired. Costal silica bodies present throughout the costal zones; mostly saddle shaped.
Transverse section of leaf blade, physiology. Lamina mid-zone in transverse section open.
C4; XyMS+. PCR sheath outlines even. PCR sheaths of the primary vascular bundles interrupted; interrupted both abaxially and adaxially. PCR sheath extensions absent. Mesophyll with radiate chlorenchyma; traversed by columns of colourless mesophyll cells. Leaf blade ‘nodular’ in section; with the ribs more or less constant in size. Midrib not readily distinguishable; with one bundle only. Bulliforms present in discrete, regular adaxial groups; associated with colourless mesophyll cells to form deeply-penetrating fans (incorporated in the traversing colourless columns). All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present (with all the bundles); forming ‘figures’ (all the bundles with I’s). Sclerenchyma all associated with vascular bundles. The lamina margins with fibres.
Cytology. Chromosome base number, x = 10. 2n = 40.
Taxonomy. Chloridoideae; main chloridoid assemblage.
Distribution, ecology, phytogeography. 4 species; North America. Species of open habitats. Dry or marshy pine barrens, inland dunes, sandy prairie.
Holarctic. Boreal and Madrean. Atlantic North American and Rocky Mountains. Canadian-Appalachian, Southern Atlantic North American, and Central Grasslands.
Rusts and smuts. Rusts — Puccinia.
References, etc. Leaf anatomical: Metcalfe 1960; this project.
Illustrations. • Abaxial epidermis of leaf blade. • Leaf blade transverse section
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).
