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BFNA Title: Diphysciaceae |
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DIPHYSCIACEAE M. Fleischer W.B. Schofield Plants perennial, medium-sized, 0.5--1 cm,
forming dense turf, with rhizoids often firmly compacting their mineral
substratum, dark to dull green; protonema producing funnel-like flaps (rarely
discernible in most specimens). Stem
short, erect, usually simple 0.5-2 mm. Leaves proximally reduced,
crowded, often crisped when dry, sometimes radially inrolled, spreading when
moist, lingulate or lingulate-subulate, rounded-obtuse to acute, mainly
entire; costa single, strong, lamina mostly 2(--3)-stratose from costa to
near margins, cells rounded-quadrate to rounded-hexagonal, thick-walled,
plane, mammillose or papillose on one or both surfaces; cells at or near base
1-stratose, hyaline, smooth, rectangular or oblong-hexagonal. Sexual condition autoicous or
dioicous. Interior perichaetial
leaves usually longer than the exterior leaves, erect, often scarious,
ovate-lanceolate, lance-subulate to linear, generally lacerate or ciliate at
apex and awned by the long-excurrent costa, brown and mainly without
chlorophyll when mature. Perigonial
shoots consisting of few, short-lingulate leaves enclosing paraphyses and
few antheridia; paraphyses filamentous.
Seta very short, smooth, lacking central strand, Capsule obliquely
oriented, nearly completely enveloped by perichaetial leaves, asymmetric,
ovoid, at the base often strongly bulging on upper side, narrowed to a conic
operculum and narrow mouth, annulus present, lacking a neck, stomata
phaneropore in 2 rows near base or absent; peristome double or sometimes
absent, with a white densely papillose endostome of 16 pleats, somewhat
twisted when dry and toothed at apex of each of the keels, exostomial teeth
rudimentary, fewer in number than the pleats. Calyptra smooth,
covering operculum. Genera 3 (1 in
flora): North America, West Indies, South America, Europe, Asia, Pacfic
Islands, Australia. The family's
three genera are Diphyscium of ca 12 species, Theriotia Cardot of two species in S.E. Asia, and Muscoflorschuetzia Crosby with one species
in Chile. The three were recently merged (Magombo 2003) into a single genus, Diphyscium, with 15 species. 1. DIPHYSCIUM
C. Mohr, Obs. Bot 34, 1803 * [Greek, di-physkion, two little guts, i.e., a little sac within a sac] Plants gregarious, forming compact short turf.
Leaves lingulate, costate, 1--2-stratose, distal cells chlorophyllose,
quadrate to isodiametric, thick-walled and papillose or mammillose or smooth,
the proximal cells rectangular, hyaline and smooth. Perigonial leaves similar to vegetative leaves, except
that the interior are reduced and enclose paraphyses, axillary hairs and
elongate antheridia. Perichaetial leaves long-awned with awn smooth or
spinulose, the awn often longer than the lamina, with the laminal apex lacerate
and ciliate, when without sporangium strongly imbricate and penicellate,
enclosing paraphyses, axillary hairs and a few archegonia. Calyptra
conic, barely covering operculum. Species 12 (2
in the flora): this is the most widespread genus of the family---mainly
temperate to subtropical in North and northern South America, Europe, Asia,
Atlantic Islands (Azores, Madeira), Pacific Islands, Australia. This genus is
sufficiently distinctive that it is unlikely to be confused with any other in
North America if perichaetia or sporophytes are present. Vegetative material is superficially
similar to that of the Pottiaceae, especially in leaf form and
papillosity. Fortunately perichaetia
and sporophytes are frequent in the genus' eastern range, while the turf
firmly cemented by rhizoids is a trait not shared by Pottiaceae in the same
range. SELECTED
REFERENCES Harvill, A. M. 1950. Diphyscium cumberlandianum, a
pre-Pliocene relic with palaeotropical affinities. Bryologiest 53: 277--282.
Magombo, Z. L. K. 2003. Taxonomic revision of the moss family Diphysciaceae
M. Fleisch. (Musci). J. Hattori Bot. Lab. 94: 1-86. Shaw, J., L. E. Anderson and B. D. Mishler. 1987. Peristome
development in mosses in relation to systematics and evolution. I. Diphyscium foliosum (Buxbaumiaceae).
Mem. N.Y. Bot. Garden 45: 55--70. 1. Vegetative
leaves blunt, leaf cells mammillose or papillose; awn of perichaetial leaves
spinulose; soil . . . 1. Diphyscium foliosum 1. Vegetative
leaves acute, leaf cells smooth; awn of perichaetial leaves smooth; rock . . 2. Diphyscium
mucronifolium 1. Diphyscium foliosum (Hedwig) C. Mohr, Obs. Bot. P 35. 1803 Buxbaumia foliosa Hedwig, Sp. Musc. P 166. 1801 Plants dark green to brownish, dull, forming
hard tufts. Stem unbranched,
erect, 0.5--1 mm, strongly radiculose.
Leaves 0.5--4 mm, crisped and imbricate when dry, margins
entire or weakly toothed with papillae, apex blunt, the most proximal leaves
shorter than the most distal, laminal cells mammillose or papillose through
most of lamima. Perichaetial
leaves brownish when mature, with spinulose awn, lamina at awn base
lacerate and membranaceous. Capsule
broadly ovoid, (2--)3--4 mm, stomata phaneropore near capsule base; mature
sporangium emergent from spreading perichaetium. Spores 6--8 mm. Capsules
mature early summer. Soil banks and soil of forest floor, also in tundra; 1--1000
m; B.C., N.B. Nfld., N.S., Ont., P.E.I., Que.; Alaska, Ala., Ark., Conn.,
Del., Ga., Ill., Ind Kans., Ky., La., Mass., Me., Md., Mo., N.C., N.H., N.J.,
N.Y., Ohio, Okla., Penn., S.C., Va., Vt.., Wis., W. Va.; Mexico; Central
America (Guatemala); Europe; Asia, Atlantic Islands (Azores, Iceland,
Madeira). In western
North America, this species is terrestrial in tundra sites, often in
blowouts; it is also found as humid perpendicular sods pendent from ledges
and on rock in canyon walls; in eastern North America on banks and horizontal
surfaces in forest. When sterile,
this terrestrial moss can be mistaken for a pottiaceous moss, but the rhizoid
compacted turf is usually enough to mark it. The unique golf-tee-like
protonemal flaps, which can be excavated from the rhizoids, are a distinctive
family trait. 2. Diphyscium mucronifolium Mitt. Bryol. Javan. 1:35.1855 Diphyscium cumberlandianum Harvill; D. involutum Mitten Plants dark green to brownish, somewhat
glossy, tightly affixed to substratum.
Stem 0.5--1 mm, erect, strongly radiculose. Leaves 0.5--5 mm, and somewhat
crisped when dry,, apex acute, the most proximal leaves reduced, laminal cells
smooth, margins entire. Perichaetial
leaves with smooth awn, 9--12 mm, lamina at awn base lacerate but not
membranaceous. Capsule
narrowly ovoid, 2--3 mm long, stomata absent, mature capsule sheathed in the penicellate
perichaetium, the awns extending to more than twice the length of the
immersed capsule. Spores 9--12
mm. Sporophytes
infrequent, capsules mature summer. Always on somewhat shaded humid rock
surfaces, especially sandstones, conglomerate and schists; 900--1000 m; Ala., Ga., Ky., N.C., Tenn., Va; se Asia (China, India, Japan,
Philippines, Sri Lanka). This is an
example of an East Asian disjunctive species, and is found only as local,
small populations. . |
