Hilpertia

R. H. Zander

Phytologia 65: 427. 1989 ,.

Etymology: For Friedrich Hilpert, b. 1907, German bryologist
Treatment appears in FNA Volume 27. Treatment on page 631. Mentioned on page 265, 480, 608, 632.

Plants in loose cushions, greenish brown distally, light-brown proximally. Stems to 1 cm, hyalodermis absent, sclerodermis not or weakly differentiated, central strand distinct; axillary hairs to 8 cells long, all hyaline or the proximal one yellowbrown. Stem-leaves crowded, larger distally, appressed and tightly spiraled when dry, weakly spreading when moist, 1–1.4 (plus 0.3–0.6 of awn) mm; ovate to circular, adaxial surface flat to quite concave, base not differentiated; distal margins strongly revolute (to 2 ×), entire or broadly dentate above, cells of revolute margin enlarged, strongly chlorophyllose; apex broadly acute, hyaline in an apical triangle; costa narrow but broader above, excurrent as a hyaline awn, lamina inserted laterally, adaxial outgrowths none, superficial adaxial cells long-rectangular, in 2–4 rows; transverse-section rounded, adaxial epidermis present, adaxial stereid band absent, guide cells 2 in 1 layer, hydroid strand present, abaxial stereid band present, rounded in cross-sectional shape, abaxial epidermis absent; basal-cells weakly differentiated, rectangular, thin-walled; distal medial cells hexagonal to shortrectangular or rhomboid, rather large, (14–) 20–25 µm wide, 1–4: 1; papillae absent medially, hollow-papillose on revolute margins, cell-walls thin to thickened and porose, superficial abaxial cell-walls thick, weakly convex superficially on both sides, cells of leaf apex rhomboid to fusiform, smooth. Specialized asexual reproduction by brood bodies borne on proximal rhizoids, brown, spheric to elliptic. Sexual condition polyoicous: synoicous, paroicous, autoicous or perigonia terminal on separate plants. Perichaetia terminal, interior leaves sheathing, usually differentiated, long-oval, margins usually somewhat differentiated, medial laminal cells rectangular, very thin-walled. Seta 0.35–0.4 cm. Capsule stegocarpous, theca elliptic, occasionally weakly ventricose, 1.2–1.5 mm, annulus of 3 rows of smaller, quadrate, highly vesiculose cells; operculum broadly short-conic to long-conic, peristome teeth 32, long, linear, twisted counterclockwise about 1/2 turn. Calyptra cucullate. Spores 13–16 µm. KOH laminal color reaction red.

Distribution

Canada, Europe, Asia

Discussion

Species 1.

Hilpertia is unique among the Pottioideae in the elaboration of a photosynthetic organ consisting of laminal marginal cells rolled in a spiral tube, thin-walled and hollow-papillose. The species is characteristic of cold steppe habitats.

Selected References

None.

"um" is not declared as a valid unit of measurement for this property.

... more about "Hilpertia"
elongate +  and quadrate +
concave +  and flat to quite +
of 1-2 rows +  and differentiated +
long-excurrent +  and short-excurrent +
Richard H. Zander +
R. H. Zander +
rounded +
rectangular +
papillose +  and smooth +
usually slightly wider +
usually ovate;oblong +
not differentiated +
obovoid +
cucullate +
stegocarpous +
monoicous +, dioicous +  and sexual +
flat to bulging +
thin;thickened +
specialized +
Few (?) +  and Several (?) +
quadrate +, rhomboid +  and fusiform +
smaller +  and enlarged +
tomentose +  and bare +
broader +
hexagonal;rhomboid;hexagonal +
Canada +, Europe +  and Asia +
differentiated +
For Friedrich Hilpert, b. 1907, German bryologist +
multicellular +
yellow +  and orange-red or red +
spiraled +  and crowded +
0.1 cm1 mm <br />0.001 m <br /> (0.14 cm1.4 mm <br />0.0014 m <br />) +
ovate;circular +
spathulate +  and ovate +
reduced +
dentate +  and entire +
differentiated +
broadly short-conic;long-conic +
photosynthetic +
compound +, simple +, hollow +  and solid +
1 +  and 4 +
lateral +  and terminal +
lateral +  and terminal +
red +, orange +  and yellow +
consisting of 16 mostly 2 times cleft spiculose striate or papillose lanceolate teeth , , , , +  and rudimentary +
straight +
elongate +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
2 +  and 1 +
red +  and laminal +
rounded-triangular +  and rounded-pentagonal +
0 cm0 mm <br />0 m <br /> (1 cm10 mm <br />0.01 m <br />) +
Hilpertia +
Pottiaceae subfam. Pottioideae +
ventricose +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
yellow distally and red +, orange +, red +  and yellow +
autoicous +, paroicous +, synoicous +, polyoicous +  and sexual +
stemless +  and perigoniate +
light-brown;greenish brown +
occasionally smaller than the perichaetiate +