Luisierella

Thériot & P. de la Varde

Bull. Soc. Bot. France 83: 73, fig. 1. 1936 ,.

Etymology: For Alphonse Luisier, 1872–1957, French bryologist
Treatment appears in FNA Volume 27. Treatment on page 641. Mentioned on page 477, 480, 642.

Plants scattered or gregarious, dull blackish green. Stems very short, 1.5–2 mm, hyalodermis absent, outer cortex undifferentiated, central strand absent; axillary hairs usually 5 cells in length, proximal cell yellowish. Leaves tubulose and contorted when dry, spreading and recurved from the insertion when moist, ligulate-lanceolate or oblong or long-elliptic, base weakly differentiated to elliptic, margins plane to erect-incurved, entire in proximal region, rounded-crenulate by bulging cells distally, lamina 1-stratose, apex rounded or rounded-obtuse to obtusely acute to occasionally cucullate; costa subpercurrent by 4–5 cells, adaxial outgrowths absent, covered ventrally with a layer of green, roundedquadrate to shortrectangular bulging cells continuous with those of the lamina but appearing elevated above them, in 4–5 rows; transverse-section elliptic to circular, adaxial epidermis strongly differentiated, adaxial stereid band absent, guide cells 2–4 (–5) in one row, hydroid strand absent, abaxial stereid band present, strong, semielliptic to semicircular in shape; basal-cells sharply differentiated in the lower 1/6 of the leaf, abruptly inflated but not bulging, smooth, rising higher along the margins and forming a V-shaped area, oblong-rectangular 2–3 (–4):1, thick-walled juxtacostally, becoming very thin and lax at the leaf margins; distal laminal cells roundedquadrate to shortrectangular, 1: 1 (–2), 1-stratose, essentially smooth, adaxial surface mammillose-bulging, abaxial surface plane, somewhat mammillose near the margins, the walls thickened, firm. Specialized asexual reproduction lacking. Sexual condition gynodioicous, fertile plants synoicous, plants with only archegonia not producing sporophytes; perichaetia terminal, interior perichaetial leaves much smaller than the cauline leaves. Seta 0.4–0.5 (–0.7) cm, rarely to 2 cm. Capsule stegocarpous, theca narrowly cylindric; annulus compound, large and strongly vesiculose in two rows, persistent; operculum narrowly high-conic; peristome teeth sixteen, linear or narrowly lanceolate, variable in development: absent, rudimentary or to 500 µm, erect. Calyptra cucullate. Spores 8–9 µm. KOH laminal color reaction negative, light yellow to orange.

Distribution

se United States, Mexico, West Indies, Central America, South America, Asia

Discussion

Species 1.

Luisierella is characterized by plants blackish, minute, with ligulate leaves tubulose when dry, laminal cells adaxially mammillose, abaxially plane, adaxial costal surface with bulging rounded cells, and adaxial stereid band absent. The abruptly thin-walled hyaline basal cells extending up the leaf margin in a V shape is distinctive; it is this latter character that quickly distinguishes this genus from similar genera: Gyroweisia, Hyophila, and Plaubelia. Luisierella bears little relation to the genus Tortella, which is also characterized by differentiated basal cells that extend higher on the leaf margin than along the costa. Luisierella has been suggested to be ancestrally related to the genus Quaesticula R. H. Zander (R. H. Zander 1993) through reduction of gametophyte characters and elaboration of reproductive ones.

... more about "Luisierella"
elongate +  and quadrate +
vesiculose +  and compound +
of 1-2 rows +  and differentiated +
insertion +
erect-incurved +
differentiated +
v--shaped +
Patricia M. Eckel +
Thériot & P. de la Varde +
semielliptic +  and semicircular +
oblong-rectangular +  and inflated +
papillose +  and smooth +
usually slightly wider +
insertion +
erect-incurved +
rounded-obtuse;obtusely acute +
differentiated +
obovoid +
cucullate +
stegocarpous +
monoicous +, dioicous +  and sexual +
flat to bulging +
vesiculose +  and thick-walled +
4 (?) +  and 5 (?) +
roundedquadrate +
tomentose +  and bare +
subpercurrent +
se United States +, Mexico +, West Indies +, Central America +, South America +  and Asia +
differentiated +
For Alphonse Luisier, 1872–1957, French bryologist +
multicellular +
yellow +  and orange-red or red +
erect-incurved +
rounded-obtuse +  and obtusely acute +
differentiated +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
concave;keeled;channeled;ovoid;lanceolate or lingulate +
spathulate +  and ovate +
reduced +
erect-incurved +
rounded-obtuse +  and obtusely acute +
differentiated +
high-conic +
undifferentiated +
photosynthetic +
compound +, simple +, hollow +  and solid +
flattened +  and 2-fid +
lateral +  and terminal +
lateral +  and terminal +
red +, orange +  and yellow +
0-500 um +  and rudimentary +
lanceolate +  and linear +
Bull. Soc. Bot. France +
crum1961a +, deguchi1987a +  and steere1945a +
straight +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
elongate +
0 cm0 mm <br />0 m <br /> (2 cm20 mm <br />0.02 m <br />) +
2 +  and 1 +
light yellow +  and orange +
rounded-triangular +  and rounded-pentagonal +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Luisierella +
Pottiaceae subfam. Pottioideae +
cylindric +
yellow distally and red +, orange +, red +  and yellow +
specialized +
sexual +  and asexual +
stemless +  and perigoniate +
plant +  and gregarious +
synoicous +, fertile +  and gynodioicous +
occasionally smaller than the perichaetiate +