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BFNA
Title: Bryoxiphiaceae |
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BRYOXIPHIACEAE
Bescherelle Ronald A. Pursell Plants small. Stems unbranched or infrequently
branched subapically, bulb-like or not at proximal end, erect or pendent,
loosely to densely tufted, rarely solitary; axillary hairs filiform, hyaline,
or the basal and adjacent cell pale tan or pale rose-violet; paraphyllia
none; pseudoparaphyllia none; rhizoids basal, light-brown to reddish, smooth.
Leaves distichous, tightly
imbricate, changing little when dry, conduplicate; 1-costate, costa
supporting a low abaxial lamella; laminal cells firm-walled, 1-stratose,
smooth, somewhat bulging. Sexual
condition dioicous; perigonia and perichaetia terminal, indistinct,
without and with paraphyses, respectively, archegonia about one-half the
length of the paraphyses; antheridia and archegonia few. Sporophytes single. Seta short,
erect or somewhat curved. Capsule subglobose,
emergent, erect or somewhat inclined, radially symmetric, stomatose; annulus
lacking; peristome lacking; operculum obliquely rostellate, persistent,
attached to columella after dehiscence. Calyptra
cucullate. Spores spheric. Genera
1, species 2 (1 in the flora): primarily temperate regions; North America;
West Indies; Europe; Asia. SELECTED
REFERENCES Britton, E. G. 1913. Bryoxiphiaceae. In: N. L. Britton et al., eds. 1905+.
North American Flora . . . . 47+ vols. New York. Vol. 15, pp.
69--70. Crum, H. A. and L. E.
Anderson. 1981. Mosses of Eastern North America. 2 vols.
New York. Vol. 1, pp. 113--116.
Löve, Á. and D. Löve.
1953. Studies on Bryoxiphium. Bryologist 56: 73--94, 183--203. Steere, W. C.
1937. Bryoxiphium norvegicum,
the sword moss, as a preglacial and interglacial relic. Ecology 18: 346--358. 1. BRYOXIPHIUM Mitten, J. Linn. Soc., Bot. 12: 580. 1869, name conserved * [Greek bryon, moss, and xiphium, sword, alluding to plant form] Plants light-green to
brownish-green, shiny. Stems with
small, incrassate, pigmented epidermal cells; exterior cortical cells similar
to epidermal cells; interior cortical cells larger, hyaline; central strand
small. Leaves oblong-lanceolate,
obtuse, becoming apiculate to aristate above, the distal, perigonial, and
perichaetial leaves long-subulate; margin nearly entire, crenate-serrulate at
leaf apex; costa smooth, strong, ending in or near leaf apex, or ending in
the subula of distal and gametoecial leaves; distal and medial laminal cells
irregularly quadrate to irregularly oblong, outer and marginal laminal cells
narrow and elongate, oblong at insertion, elongate in subula. Sporophytes rare. Spores smooth, or nearly so. Widespread
but disjunct: largely temperate Northern Hemisphere. 1.
Bryoxiphium norvegicum (Bridel) Mitten, J. Linn.
Soc., Bot. 12: 580. 1869 Phyllogonium norvegicum Bridel, Bryol. Univ. 2: 674. 1827 Plants 4--30 mm, 0.5--1.5 mm
wide (not including the flaring distal subulate leaves). Leaves somewhat scale-like below; median leaves
oblong-lanceolate, rounded or nearly so, 1-2 mm, becoming apiculate to
aristate; distal and gametoecial leaves 3--6 mm, long-subulate with more or
less twisted, more or less hyaline, flexuous, smooth to spinose subula; costa
ending a few cells below apex in proximal and median leaves, ending in subula
of distal and gametoecial leaves, interior cells of homogeneous stereids,
exterior layer thinner walled; abaxial lamella 1--6 cells high, sometimes
lacking, usually developed best on subulate leaves, usually ending well above
insertion; interior laminal cells 11--40 × 9--18 µm; marginal cells 14--60 ×
3.5--7.0 µm. Seta ca. 2 mm;
capsule ca. 1 mm. Spores 19--23
µm, slightly papillose. Capsules
mature July. Usually on undersides
of moist, shaded, sandstone ledges and cliffs, these occasionally calcareous
and often overhanging streams, infrequently on bluffs and boulders of
conglomerate, gneiss and quartzite, soil, and overturned tree bases; 50--2750
m; Greenland; Alaska, Ark., Ariz., Colo., Ind., Iowa, Ky., Minn., Mo.,
N.Mex., N.C., Ohio, Tenn., Wash., Wis.; Mexico; West Indies (Dominican
Republic); Atlantic Islands (Iceland, Madeira); Asia. Mature
spores have been found only once in North America, in a sporophyte collected
in the Wisconsin Dells in July. According to S. M. Hague and W. H. Welch
(1951), antheridia are present from March to August, and archegonia are evident
from May to August. In spite of the specific epithet, the original collection
of this distinctive moss was made in Iceland. Usually bright-green, B. norvegicum
has on occasion been mistaken for grass seedlings. Bryoxiphium can also be confused with another moss genus, Fissidens. In both genera the leaves
are distichously arranged, and the conduplicate (folded lengthwise) portion
and weak abaxial lamella of the larger and better developed leaves of Bryoxiphium can be mistaken for the
vaginant and abaxial laminae, respectively, of Fissidens. Costal structure of the two genera, however, is quite
different, and species of Fissidens,
with few exceptions, have a well-developed haplolepidous peristome. Á.
Löve and D. Löve (1953) recognized two subspecies of Bryoxiphium norvegicum,
subsp. norvegicum and subsp. japonicum, distinguished on the degree
of serrulation on the distal parts of the perichaetial leaves. Within subsp. norvegicum they recognized two
varieties, norvegicum and mexicanum (the latter variety
recognized at the species level by H. A. Crum in A. J. Sharp et al. (1994),
based on differences in the length of marginal cells in perichaetial leaves.
According to Löve and Löve, North American populations north of Mexico belong
to var. norvegicum, having
perichaetial leaves only slightly serrulate and marginal cells much longer
than the interior laminal cells. A report of B. norvegicum from
Pennsylvania cannot be substantiated. OTHER
REFERENCES Hague,
S. M. and W. H. Welch. 1951. Observations regarding scarcity of
sporophytes in Bryoxiphium norvegicum. Bryologist 54: 214--215. Sharp, A. J., H. A. Crum, and P. M. Eckel, eds. 1994. The Moss Flora of Mexico. Mem. New York Bot. Gard. 69. |
