Echinaria Desf.
From the Greek echinos (hedgehog), re a globular, prickly inflorescence.
Including Panicastrella Moench
Habit, vegetative morphology. Annual; erect or ascending. Culms 1.525 cm high; herbaceous. Culm nodes glabrous. Leaves non-auriculate. Sheath margins joined. Leaf blades linear; narrow; 1.55 mm wide; flat; without cross venation; an unfringed membrane (but ciliolate); truncate; 0.5 mm long.
Reproductive organization. Plants bisexual, with bisexual spikelets; with hermaphrodite florets. The spikelets of sexually distinct forms on the same plant (with sterile, reduced members at the base of the inflorescence), or all alike in sexuality; often hermaphrodite and sterile; overtly heteromorphic (sterile-reduced versus fertile), or homomorphic.
Inflorescence. Inflorescence paniculate; contracted (prickly); capitate, or more or less ovoid (515 mm long); espatheate; not comprising partial inflorescences and foliar organs. Spikelet-bearing axes persistent. Spikelets associated with bractiform involucres (constituted by the basal, sterile spikelets), or unaccompanied by bractiform involucres, not associated with setiform vestigial branches; not secund; shortly pedicellate, or subsessile.
Female-sterile spikelets. The sterile spikelets, when present, basal and bractlike.
Female-fertile spikelets. Spikelets 412 mm long; compressed laterally to not noticeably compressed; disarticulating above the glumes. Rachilla prolonged beyond the uppermost female-fertile floret. Hairy callus present. Callus short.
Glumes two; relatively large (membranous); very unequal to more or less equal; shorter than the spikelets; long relative to the adjacent lemmas; mucronate to awned (the lower with 25 veins excurrent as awns, the upper with an excurrent midrib); carinate. Lower glume 25 nerved. Upper glume 1 nerved. Spikelets with female-fertile florets only, or with incomplete florets. The incomplete florets distal to the female-fertile florets.
Female-fertile florets (1)34. Lemmas decidedly firmer than the glumes (leathery); not becoming indurated; awned. Awns 5, or 7; median and lateral (the 57 strong lemma veins being produced as flattened awns which become deflexed at maturity, the middle awn the longest); the median similar in form to the laterals; apical; non-geniculate; recurving (deflexing); much longer than the body of the lemma (lemma 2 mm long, the middle awn 46 mm long); entered by one vein. The lateral awns shorter than the median. Lemmas hairy; non-carinate; without a germination flap; 57 nerved. Palea present; relatively long; awned (two or rarely five veins produced as flattened awns); 2-nerved, or several nerved (up to 5); 2-keeled. Lodicules present, or absent; when present, 2; free; membranous; glabrous; not toothed; not or scarcely vascularized. Stamens 3. Anthers 0.81.3 mm long. Ovary hairy. Styles fused. Stigmas 2.
Fruit, embryo and seedling. Fruit free from both lemma and palea; small (2 mm long); not noticeably compressed; with hairs confined to a terminal tuft. Hilum short. Embryo small. Endosperm hard; without lipid; containing compound starch grains. Embryo with an epiblast.
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 and fusiform; having markedly sinuous walls. Microhairs absent. Stomata common (fairly, but mostly alongside the veins); 3639 microns long. Subsidiaries parallel-sided. Guard-cells overlapped by the interstomatals. Intercostal short-cells absent or very rare. Prickle bases abundant. Costal short-cells neither distinctly grouped into long rows nor predominantly paired (mostly solitary). Costal silica bodies horizontally-elongated crenate/sinuous (mostly), or horizontally-elongated smooth.
Transverse section of leaf blade, physiology. C3; XyMS+. Mesophyll without adaxial palisade. Midrib not readily distinguishable; with one bundle only. The lamina symmetrical on either side of the midrib. Bulliforms present in discrete, regular adaxial groups; in simple fans. All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present (but the largest bundles with abaxial strands only); forming figures (Is). Sclerenchyma all associated with vascular bundles.
Cytology. Chromosome base number, x = 7 and 9. 2n = 14 and 18. 2 ploid. Chromosomes large.
Taxonomy. Pooideae; Poodae; Seslerieae.
Distribution, ecology, phytogeography. 1 species; Mediterranean, eastern Asia. Xerophytic; species of open habitats.
Holarctic. Boreal and Tethyan. Euro-Siberian. Mediterranean and Irano-Turanian. European.
Rusts and smuts. Rusts Puccinia. Taxonomically wide-ranging species: Puccinia hordei.
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).