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BFNA Title: Tetralophozia |
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XX.
TETRALOPHOZIA (R.M. Schuster) Schljakov, Novosti Sist. Nizsh. Rast. 13: 227.
1976 * [Greek tetra, four, and genus Lophozia,
alluding to the 4-fid lateral leaves] Edi Urmi Chandonanthus subg. Tetralophozia R.M. Schuster, J. Hatt. Bot. Lab. 23: 206. 1960 Plants simple or sparingly branched, shoot
tips often antically bent, creeping among other foliose hepatics, ascending
in loose mats, or ± upright in tightly packed cushions, ocher or brown,
rarely green. Stems with ventral-
and lateral-intercalary branches, rarely terminally branched (Frullania-type); cell walls in transverse
section ± thickened, the surface wall of the epidermis the thickest, cell
size gradually increasing from periphery to center; paraphyllia lacking
except for gametangia; rhizoids hyaline, few or many, dependent on habit. Lateral leaves subtransversely inserted,
succubous, imbricate or contiguous, hardly different in wet and dry
condition, uneven, symmetrically divided in 4 lobes to more than half leaf
length; lobes triangular, canaliculate, the margins coarsely and spinosely
toothed or ciliate; basal cells ± elongated, lobe cells less so, all with
distinct trigones often bulging, surface verruculose; oil bodies few per
cell, botryoidal. Underleaves similar
to lateral leaves, but a little smaller, 2-fid, and with narrower lobes. Specialized asexual reproduction rare
(known only in T. setiformis),
1--2-celled gemmae on leaf margins. Sexual
condition dioicous. Androecia intercalary,
exactly as wide as vegetative parts (easily overlooked), number of bracts per
androecium obviously indefinite (1--20), bracts similar to lateral leaves,
but less deeply divided and somewhat saccate at base, bracteoles not bearing
antheridia, antheridia (1--)2(--4) per bract, white or somewhat reddish,
jacket cells not clearly tiered, 1 or 2 cell rows in antheridial stalk. Gynoecia terminal on long shoots,
usually with 1 ventral-intercalary innovation, bracts and bracteole hardly
differentiated; perianth longly exserted, ± cylindric and often antically
curved, strongly plicate, mouth lobed and ciliate. Sporophytes rather large. Seta
transverse section with many homogeneous cells. Capsule black, ellipsoid, dehiscent with 4 lobes, wall layers 4,
outer and innermost layer with brown nodular thickenings along the cell
walls. Elaters free, 2-spiral. Spores spherical, brown. Species
4 (2 in the flora); North America, Arctic, Europe, Asia, Africa. SELECTED
REFERENCES: Godfrey, J. D. and G. A. Godfrey, 1978. Asexual reproduction in Chandonanthus setiformis. Bryologist
81: 326--330. Laine, T. 1970. Notes on
Chandonanthus Mitt. subg. Tetralophozia Schuster. Ann. Bot.
Fenn. 7: 163--169. Schuster, R.M.
1966--1992. The Hepaticae and Anthocerotae of North America east of the
hundredth meridian. 6 vol. (Chandonanthus
in vol. 2: 241--252). Schuster, R.M. 2002.
Revisionary studies of the Chandonanthoideae (Jungermanniales,
Jungermanniaceae). Nova Hedwigia 74: 465--496. Urmi, E. 1983. Tetralophozia filiformis (Steph.) comb. nov. in Europa. J. Bryol.
12: 393--401. 1.
Well developed shoots rarely more than 4 cm and seldom wider than
0.6 mm; lateral leaves with narrowly triangular lobes always more than
twice as long as wide; lobes abaxially canaliculate, their margins abaxially
recurved; fully developed perianths less than 1.5 mm .............................................................................................
1. Tetralophozia filiformis 1.
Well developed shoots often 5--10 cm and often 0.6 mm or more in width;
lateral leaves with broadly triangular lobes less than twice as long as wide;
lobes abaxially concave, their margins incurved towards the stem; fully
developed perianths longer than 1.5 mm
.....................................................................................
2. Tetralophozia setiformis 1. Tetralophozia filiformis (Stephani) Urmi, J. Bryol.
12: 394 Chandonanthus filiformis Stephani, Sp. Hepat. 3: 645.
1909 Plants 3--20 (--40) x (0.1--)0.2--0.6(--0.9)
mm, as ± dense mats or cushions, yellowish or greenish brown. Stems
(50--)100--150 \um wide, with ventral or lateral intercalary branches;
cells with ± thickened walls; paraphyllia lacking; rhizoids if any, in loose
groups closely proximal to underleaves, hyaline. Lateral
leaves mostly imbricate, uneven, sometimes spreading, (0.1--)0.2--0.5 x 0.2--0.9 mm, hand-like,
very deeply divided in four lobes, sinuses dorsally protruding, antical
margin often with a very large tooth;
lobes narrowly ovate and acute, more than twice as long as wide,
abaxially canaliculate; cells ±
elongated (except for marginal ones), subbasal
cells 12--24(--32) x 10--17 \um, surface verruculose, with trigones (near
leaf base bulging); oil bodies 3--5 per cell.
Underleaves similar to
lateral leaves, 2-fid and with narrower lobes. Androecia bracts less deeply divided than lateral
leaves, less dentate, antheridial
stalk uniseriate, jacket cells somewhat tiered. Perianths when fully developed less than 1.5 mm. Sporophytes not seen in region of
flora. Shaded
siliceous rock outcrops in the Pacific rain forest with high air humidity,
often on a thin layer of rather wet soil with dead organic material,
sometimes on dead wood or even epiphytic on tree bases, often admixed with Anastrophyllum minutum, Bazzania sp., Dicranum fuscescens, Diplophyllum
taxifolium, and Scapania bolanderi,
occasionally with Tetralophozia
setiformis; low to moderate elevations (0--600 m); B.C.; Europe; Asia. Tetralophozia filiformis shows a highly disjunctive
distribution. Its American population is at a distance of 5500 km from the
E-Asian ones in Siberia and of 8000 km from the European. 2. Tetralophozia setiformis (Ehrhart) Schljakov,
Novosti Sist. Nizsh. Rast. 13: 228. 1976 Jungermannia setiformis Ehrhart, Hannover. Mag. 22,
8: 142. 1784; Chandonanthus setiformis (Ehrhart)
Lindberg; Temnoma setiforme (Ehrhart)
Howe; Tetralophozia setiformis var.
alpina (Hook.) L. Söderstr. Plants (5--)10--40(--150) x
(0.2--)0.5--0.8(--1) mm, longer plants sometimes sympodial by innovations,
wiry and brittle when dry, in low mats
or in densely packed cushions, ocher, brown, or rarely green. Stems
mostly 200 \um wide, but from 80 to 300 \um, branching lateral- and
ventral-intercalary, rarely terminal; cells somewhat thickened, those of
medulla porose; paraphyllia lacking (except for androecia); rhizoids if any,
in loose groups closely proximal to underleaves, hyaline. Lateral
leaves imbricately overlapping,
very uneven, base spreading but lobes upright and parallel to the stem,
deeply and symmetrically divided in four lobes, sinuses abaxially protruding,
antical margin lacking a large tooth, (0.2--)0.4--0.6 mm long and
(0.2--)0.5--1(--1.3) mm wide (the smaller ones with 3 or even only 2
lobes); lobes all broadly ovate and
acute, less than twice as long as wide, abaxially concave but the upper
margins incurved towards the stem;
cells somewhat elongated subbasally, (13--)18--25(--30) x
(12--)15--20(--23) \um, those of lobes ± quadrate, surface smooth or
verruculose, cell walls with trigones rarely bulging; oil bodies 2--4 per
cell. Underleaves transversely inserted and contiguous, symmetrical,
2-fid, and with much narower lobes. Androecia bracts similar to leaves
and with transitional forms, antheridial stalk 1- or 2-seriate, jacket cells
not tiered. Perianths when fully
developed longer than 1.5 mm. Sporophytes rare. Seta
about 10 mm, cross section with one layer of quadrate cells, homogeneous
interior ca. 10 cells across. Capsule 1.2 x 1 mm. Elaters
worm-like, about 120 x 10 \um, brown.
Spores 15--18 \um, finely
spinulose. Capsules
mature in summer. Mountain slopes in Arctic or alpine tundra and in boreal
forests, scrubs or dwarf shrub heaths, rarely on ground and not often in wet
places, predominantly in exposed (rather than shaded) dry or mesic sites,
preferred substratum a thin soil layer of mineral material and humus on
siliceous rock outcrops or boulders, often admixed with Racomitrium lanuginosum, various lichens, ten different species
of Lophozia, four different Anastrophyllum species, Ptilidium ciliare, Dicranum sp., Andreaea sp. Gymnomitrion sp., and occasionally together with Tetralophozia filiformis; low to high
elevations (0--2000 m); Greenland; Alta., B.C., Nfld., Nun., N.W.T., Ont.,
Que., Yukon; Alaska, Maine, N.H., N.Y., Vt.; Arctic; Europe; Asia. Tetralophozia setiformis is a variable species, some
of its modifications being very different from the more common form. The
basal cilia often end in slime papillae. Sporophytes are extremely rare. I am
aware of one single collection with young sporophytes from America (Steere 62-956).
The above description is therefore based on European material I found fertile
just once and with ripe capsules in Scandinavia. "Tetralophozia setiformis var. alpina", e.g., is very slender with small 3- or even 2-fid
leaves. It occurs (with transition forms) within pure stands of normally
grown plants or as whole populations under unfavourable conditions. I
consider them in accord with Schuster (1966--1992, vol. 2, p. 251 f.) as mere
modifications. |
