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BFNA Title: Odontoschisma |
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XX. ODONTOSCHISMA (Dumortier) Dumortier, Recueil Observ. Jungermann.,
19. 1835 * [Greek ondonto,
tooth, and schisma, a split;
possibly alluding to sinused bracts with one or more marginal teeth] David M. Krayesky Lorinda Leonardi Jerry G. Chmielewski Pleuroschisma sect. Odontoschisma Dumortier,
Syll. Jungerm. Europ., 68. 1831 Plants pale to yellow
green to reddish or yellowish or brownish or purplish in color. Stem
cortical and medullary cells similar, without differentiated superficial
cells, except in O. sphagni;
ventral branching and flagelliform branches common; rhizoids postical on
primary shoots and flagelliform branches, hyaline. Leaves
succubous, not decurrent, wide to erect-spreading, distant to imbricate,
rotuntate to oblong, entire or rarely with a few teeth; unlobed to 2-lobed,
lobes slightly asymmetrical and sinus acute to obtuse, flat or slightly to
distinctly concave; cuticle papillose to slightly papillose or smooth. Leaf cells round or quadrate to
elongate; thin- to thick-walled; trigones absent or small to large. Oil bodies papillose to granular-botryoidal, ellipsoidal to ovoid or round. Underleaves
0--1 per pairs of lateral leaves, 2--7 cells in width at base, mostly
lanceolate to quadrate, entire to 2-lobed, lobes ciliate or lanceolate,
margins and apices smooth with or without slime papillae; cells round or
quadrate to elongate, medium to thick-walled, trigones absent to small or
large. Rhizoids hyaline, scattered ventrally or absent. Specialized
asexual reproduction by gemmae in some species, green to red, 1--2
celled, ellipsoidal to oval to triangular and occasionally stellate, forming
at shoot apex on leaf margins of erect growing stem tips. Sexual
condition dioicous. Androecia terminal or intercalary on
stems or branches; bracts imbricate, 3--18 pairs, mostly 2-lobed, erect,
concave, toothed or entire at base, with or without slime papillae at apices
or along margins; bracteoles similar to underleaves but smaller; antheridia
orbicular, hyaline, yellow-orange, bronze or red-purple, 60--200 µm in width,
1 per bract; jacket cells irregularly orientated; stalks 2 cells in width,
3--8 cells in length. Gynoecia terminal on postical or
lateral intercalary branches, bracts 2--4 pairs, 2-lobed, concave, longer
than leaves, with or without slime papillae along margins, bracteoles mostly
similar in size and shape to bracts; connate, adnate, or free; stem-derived
protective structure absent. Perianth 0.5--0.9 µm in diameter,
exerted, oblong to cylindrical; mouth tapered to slightly tapered, sinuate to
lobed, crenate to ciliate to entire; (1--)2(--3)-stratose near base,
1-stratose near mouth; without surface ornamentation. Sporophyte
seta cross section (99--)104--221 µm in diameter; 8 or 13--18 exterior cell
rows and 4 or 5--16 interior cell rows depending on species; capsule 0.7--1.2
x 0.3--0.5 mm; ovoid, 4-valved, outer cells with nodular rust-colored
thickenings, inner cells with semiannular rust-colored thickenings. Elaters
with tapered or truncate ends, 2(--3)spiraled, spirals 2.5--4 µm in width,
rust-red. Spores papillose, rust-red to purple. Species 21 (6 in the flora): North America; West
Indies; Bermuda; Central America; South America; Europe; Asia; Africa;
Atlantic Islands; Indian Ocean Islands; Pacific Islands. J. A. Patton (1999) suggested approximately
30 species worldwide; however, S. R. Gradstein and A. L. Ilkiu-Borges (2015)
and S. C. Aranda et al. (2014) provide ample evidence to support the
delimitation of only 21 Odontoschisma
species, based on molecular evidence, and anatomical characters (i.e. a stem
lacking a hyalodermis, large trigones, large oil bodies, and non-tiered
antheridial jacket cells); therefore, we follow their assessment of the
genus. SELECTED
REFERENCES Aranda, S. C., S. R.
Gradstein, J. Patiňo, B. Laenen, A. Désamoré, and A. Vanderpoorten. 2014.
Phylogeny, classification, and species delimitation in the liverwort
genus Odontoschisma
(Cephaloziaceae). Taxon 63:
1008--1025. Bednarek-Ochyra, H., J.
Váňa, R. Ochyra, and R. I. Lewis-Smith.
2000. The liverwort flora of
Antartica. Polish Academy of Sciences,
Institute of Botany, Cracow. Chen,
F.-D., X.-D. Li, and H. Kanada. 1993.
An investigation of the bryophytes in the Fildes Peninsula, King
George Island, Antartica. Antarctic
Reseach (Chinese Edition) 5: 46--50. [In Chinese with English summary]. Chen, F.-D., X.-D. Li, and J.-X. Ziu. 1995.
Handbook of the Fildes Peninsula Antarctica mosses. Ocean Press,
Beijing, China. [In Chinese]. Evans,
A.W. 1903. Odontoschisma
macounii and its North American allies.
Botanical Gazette 36: 321-348.
Gradstein, S. R. and A .L. Ilkiu-Borges. 2015.
A taxonomic monograph of the genus Odontoschisma. Nova Hedwigia 100: 16-100. Jensen,
C. 1897. Mosser fra Øst-Grønland. Meddelelser om Grønland 15: 365--443. Li, X.-D.. J.-X. Liu and F.-D. Chen. 1998.
A preliminary study of the bryoflora of the Fildes Peninsula, King
George Island, Antarctica. J. Hattori
Bot. Lab. 84: 199--202. Paton, J. A. 1999.
The Liverwort Flora of the British Isles. Harley Books, Colchester, England. Schuster, R. M. 1974.
Odontoschisma. In: R. M. Schuster. The Hepaticae and Anthocerotae of North
America east of the hundredth meridian. New York, Vol. 3. Pp. 678--695 and 829--870. 1.
Leaves 2-lobed; seta with 13--18 exterior cell rows and 5--16 interior cell
rows in cross section.
1.
Leaves not lobed; seta with 8 exterior cell rows and 4 interior cell rows in
cross section
4.
Middle lamella of the leaves distinct,
trigones deeply pigmented golden to brownish and well defined
……………….…………..... 4. Odontoschisma
elongatum 4. Middle lamella of the leaves not visible,
trigones not deeply pigmented or well defined. 5. Leaves generally emarginate at apex; large
underleaves large, mostly the length of the vegetative leaves; cuticle of leaves
smooth …………………………………………………. 5. Odontoschisma
macounii 5. Leaves not distinctly emarginate at apex;
underleaves minute; cuticle of leaf papillose ……………………………….…. 6. Odontoschisma denudatum 1. Odontoschisma
fluitans (Nees) L.
Söderström. & Váňa, Phytotaxa 112: 12. 2013 Jungermannia fluitans Nees, Flora 6: 30. 1823;
Cladopodiella fluitans
(Nees) Jörgensen Plants yellow-brown,
green or purple-black, ca. 20--45(--100) mm, prostrate, growing among other
bryophytes or in mats. Stems
150--200 µm in diameter, without cortical differentiation, cortex and medulla 6--8 cells in width, cortical cells in
transverse section 30--90 x 20--27 µm; flagelliform branches common. Leaves oblong, 2-lobed,
lobes slightly asymmetrical, sinus acute to obtuse, mostly distant but
contiguous to slightly imbricate, flat to slightly concave, 500--1100 x
400--800 µm; lobed 0.2--0.4 leaf length, largest leaf lobe 7--15
cells in width at base, lobe apices obtuse to occasionally acute; cuticle
smooth. Leaf cells at margins 15--38 µm, at midleaf in lobes 20--40 µm,
at base 15--60 µm; trigones absent or small; oil bodies 3--10 per cell, 4--10
µm. Underleaves distant, 200--500 x 50--150 µm, cells 12--75 µm. Specialized
asexual reproduction absent. Androecial bracts 0.4--0.7 x 0.4--0.6
mm. Gynoecial bracts 0.8--1.2 mm.
Perianth 2.5--4 x 0.7--1
mm; cylindrical; mouth sinuate, entire to crenulate. Sporophyte capsule wall 3 cell layers, 30--35 µm in thickness,
outer cells 10--18 µm in width, inner cells 10--13 µm in width. Elaters 125--250 x 10--13 µm, 2-spiraled. Spores 15--20 µm. Acidophile, often
growing intermingled with sphagnum or peat in pools, less commonly on moist
soil or rock; bogs, lake and pond edges, moist open areas; mostly low to
moderate elevations; Greenland; Alta., B.C., Man., N.B., Nfld. & Labr., N.W.T., N.S., Ont., P.E.I, Que.; Alaska, Conn., Maine,
Mass., Mich., Minn., N.H., N.J., N.Y., Ohio, R.I., Vt., Wash., W.Va., Wis.;
Europe; Asia; Africa. Sometimes
confused with the more common Gymnocolea
inflata. Odontoschisma fluitans may be easily identified if perianths are present. The perianths of O. fluitans, which are more elongate than the more globose
perianths of G. inflata, do not
become detached from the stem. Also O. fluitans does not develop terminal
or lateral branches as does Gymnocolea.
2. Odontoschisma
francisci (Hooker) L. Söderström
& Váňa, Phytotaxa 112: 12. 2013 Jungermannia francisci Hooker, Brit. Jungermann., pl. 49. 1813; Cladopodiella
francisci (Hooker) Jörgensen Plants green or purple-red,
ca. 3--15 mm, prostrate with erect branches, growing in mats or among other
bryophytes. Stems 120--150 µm in
diameter, without cortical
differentiation, cortex and
medulla 5--7 cells in width, cortical cells in transverse section 20--65 x
10--30 µm; flagelliform branches common. Leaves ovate, 2-lobed, lobes slightly asymmetrical, sinus acute
to obtuse, mostly imbricate but contiguous to distant, concave to slightly
concave, 300--500 x 200--400 µm, lobed 0.1--0.3
leaf length, largest leaf lobe 5--8 cells in width at base, lobe apices acute
to obtuse; cuticle smooth. Leaf cells at margins 10--28 µm, at
midleaf in lobes 10--25 µm, at base 18--45
µm; trigones absent or small; oil bodies 1--5 per cell, 4--8(--14)
µm. Underleaves distant to imbricate, 110--180 x 60--110 µm, cells
7--38 µm. Specialized asexual reproduction by gemmae often present, forming
on leaf margins of erect stem tips, stellate, 3--6-angled, 1---2 cells,
17--33 µm. Androecial bracts 0.1--0.5 x 0.1--0.3 mm. Gynoecial
bracts 0.6--1 mm. Perianth 1.8--2.5 x 0.7--0.9 mm;
cylindrical; mouth sinuate to lobed, entire to crenulate. Sporophyte
capsule wall 2--3 cell layers, 20--30 µm in thickness, outer cells 10--15
µm in width, inner cells 5--8 µm in width.
Elaters 65--170 x 8--10 µm,
2-spiraled. Spores 12.5--15 µm. Acidophile, often
forming uniform patches on moist sandy to gravelly soil and less common on
peat; wetlands, heathlands, lake and pond edges, roadsides, and cliff ledges;
low elevations to alpine summits; Greenland; Nfld. and Labr. (Nfld.), N.S.,
Que.; Conn., Maine, Mass., N.H., N.Y., R.I.; Europe. Because of its
size and form, Odontoschisma francisci may be confused with species of Cephalozia, but absence of a hyalodermis and the non-decurrent leaves
will readily distinguish this species.
In ideal conditions, O.
francisci can be form abundant uniform patches. 3. Odontoschisma sphagni (Dickson)
Dumortier, Recueil Observ. Jungermann., 19.
1835 Jungermannia
sphagni Dickson, Fasc.
Pl. Crypt. Brit. 1: 6. 1785; Odontoschisma
prostratum (Swartz) Trevisan Plants pale tinged with
brown to reddish brown (all pale green in shade forms), ca. 0.7--29 x
0.7--2.0 mm, prostrate, growing in mats or singly among other
bryophytes. Stems 145--174 µm in diameter, with cortical differentiation, cortex and medulla 13--14 cells in width, cortical cells
in transverse section 5--8 x 7--11 µm; flagelliform branches common. Leaves
suborbicular to rounded-oblong to subrotund with apex rounded, distant to
imbricate, flat to moderately concave, 418--498 x 456--535 µm; cuticle
slightly papillose. Leaf cells at margins 10--15 x 10--15
µm, at midleaf 12--20 x 12--19 µm, at base 14--23 x 24--31 µm; trigones
small; oil bodies 2--4(--5) per cell, 3--12 µm. Underleaves
distant, 125--148 x 56--60 µm, cells 14--20 µm. Specialized
asexual reproduction gemmae absent.
Androecia bracts 0.3--0.4 x 0.3--0.4 mm. Gynoecia
bracts 1--1.2 mm. Perianth
3.0--4.5 x 0.8--0.9 mm; cylindrical; mouth lobate, ciliate with teeth. Sporophyte
capsule wall of 2 cell layers, 20--25 µm in thickness, outer cells 11--13 µm in width, inner cells 9--11 µm in
width. Elaters 122--236 x 10--11 µm, 2-spiraled. Spores
(7--)9--11 µm. Temperate and tropical
from near sea level to upland forests, on peat moss (rarely on other mosses),
peaty soils, sandy soils, gravelly soils, decaying logs, rarely on tree bases, bogs,
swamps, and upland forests in noncalcareous habitats, from hydric to xeric.;
low to high elevations; Greenland; St. Pierre and Miquelon; Alta., N.B.,
Nfld. and Labr., N.S., Ont., Que., Yukon; Ala., Alaska, Ark., Conn., Del.,
D.C., Fla., Ga., Ill., Ky., La., Maine, Md., Mass., Miss., Mo., Mont., N.H.,
N.J., N.Y., N.C., Ohio, Pa., R.I., S.C., Tenn., Tex., Vt., Va., W.Va., Wyo.;
Mexico; West Indies; Bermuda; Europe; Atlantic Islands. Gradstein and
Ilkiu-Borges (2015) suggest O. sphagni
does not occur in South America or Asia as collections cited from these
localities belong to O. variabile
and O. denudatum,
respectively. Schuster (1974)
indicated that the Spruce 1882 report of O.
sphagni from Africa is erroneous.
The Spruce collection is unavailable; however, since we have been
unable to find other reports of O.
sphagni from that region we support Schuster’s hypothesis. 4. Odontoschisma elongatum (Lindb.) A. Evans, Rhodora 14: 13. 1912 Odontoschisma
denudatum fo. elongatum Lindberg, Helsingfors Dagblad 1874(45):
[2]. 1874 Plants yellow green
tinged with brown or plants blackish brown (rarely all green), ca. 5.0--15
x 1--1.9 mm, gregarious, prostrate
with ascending apices, growing in mats or singly among other bryophytes. Stems
163--216 µm in diameter, without cortical differentiation, cortex and medulla 8--9 cells in width, cortical cells in
transverse section 9--27 x 14--21 µm; flagelliform
branches uncommon. Leaves
subrotund with apex rounded, distant to imbricate, slightly to moderately
concave, 427--525 x 446--590(--739) µm; cuticle smooth. Leaf
cells at margins 11--17 x 10--15 µm, at midleaf 10--19 x 15--22 µm, at
base 14--25 x 15--23 µm; trigones small to moderate to large; oil bodies
(1--)2--3(--4) per cell, 5--13 µm. Underleaves
distant, 123--199 x 86--89 µm, cells 19--25 µm. Specialized
asexual reproduction gemmae uncommon, forming at the tips of ascending
shoots, suborbicular to ovate to elliptic, 1--2 cells, 50--70 µm. Androecia bracts rare, 0.3 mm
long. Gynoecia bracts rare,
0.7--0.9 mm. Perianth rare, 2.0 x 0.5 mm; cylindric; mouth crenulate. Sporophyte
capsule wall not observed. Elaters 163--229 x 8--9 µm,
2-spiraled. Spores 8--10 µm. Circumpolar in
acidic areas, muddy, sandy, gravelly, or rocky substrates, occasionally peaty
humus, rotten wood,
moorlands, heaths, and in moors around lakes, ponds, bogs, and marshes with Sphagnum; near sea level to
alpine; Greenland; B.C.,
Nfld. and Labr. (Nfld.), N.W.T., N.S., Ont., Que.; Alaska, Maine, Mass.,
Mich., N.H.; Europe; Asia. Sporophytes are
very rare; however, a prepared slide of capsule material from RMS 11730 in
(F) had some elater and spore material.
Due to the deteriorating condition of the slide only spore and elater
anatomy could be determined.
Additionally, mature perianths are rare; however, sample RMS 12239 in
(F) was reported to have few perianths (by Schuster), but presently the
sample appears barren. As sexual
structures of the gametophyte were not observed in the material examined
measurements for androecial bracts, gynoecial bracts, and perianths are derived
from Patton (1999). 5. Odontoschisma macounii (Austin)
Underwood, Bull. Illinois State Lab. Nat. Hist. 2: 92. 1884 Sphagnoecetis
macounii Austin, Bull.
Torrey Bot. Club 3: 13. 1872 Plants yellowish to pale
green, ca. 6.0--13.0 x 0.7--1.2 mm, prostrate, growing in small mats or
singly among other bryophytes. Stems (141--)163--183 µm in diameter,
without cortical differentiation, cortex and
medulla 9--10 cells in width, cortical cells in transverse section 10--16 x
7--12 µm; flagelliform branches common. Leaves subrotund, apex emarginate,
loosely to highly imbricate, strongly concave, 341--579 x 252--771 µm;
cuticle smooth. Leaf cells at margins 15--21 x 13--14 µm, at midleaf 15--18 x
14--24 µm, at base 22--34 x 15--19 µm; trigones small to large; oil bodies
1--3--(4) per cell, 6--14 µm. Underleaves
distant, 62--176(--407) x 73--121(--274) µm, cells 20--28 µm. Specialized asexual reproduction by
gemmae common, forming at the tips of erect shoots, subelliptic to elliptic,
1--2 cells, 20--35 µm. Androecia bracts 0.2--0.3 x 0.2--0.2 mm.
Gynoecia bracts 1.2--1.4 mm. Perianth
3.5--4.0 x 0.8--0.9 mm; cylindrical; mouth irregularly lobate, entire to
slightly crenate. Sporophyte capsule wall of 2 cell layers, 25--55 µm in thickness,
outer cells 22--34 µm in width, inner cells 10--21 µm in width. Elaters
(78--)117--224 x 10--13 µm, 2(--3)-spiraled.
Spores 12--16 µm. Circumpolar,
arctic-alpine, and with meta-populations along Lake superior, restricted to
calcareous and exposed sites, on organic matter (generally humus or peat)
atop calcium-rich rock or associated with calcium rich seep; elevation low to
high; Greenland; B.C., Man., Nfld. & Labr., N.W.T., N.S., Nunavut, Ont.,
Que., Yukon; Alaska, Mich., Minn., Wis.; Europe; Asia. Schuster (1974)
reported populations of Odontoschisma
macounii occasionally occur at locations further south in boreal forest
zones which represent relic sites for the present distribution of this
species. The reports by
Chen et al. (1993; 1995) and Li et al. (1998) of O. macounii from Antarctica are erroneous as these reports have
been demonstrated by Bednarek-Ochyra et al. (2000) to be Herzogobryum teres (Carrington & Pearson) Grolle. 6. Odontoschisma denudatum (Nees) Dumortier, Recueil
Observ. Jungerm., 19. 1835 Jungermannia
denudata Nees, Fl. Crypt.
Erlang., 14. 1817 Plants pale green or
yellow green tinged brown, red, or purplish black or blackish green to
blackish brown or violet purple with a metallic like sheen, 8.0--12.0 x
0.5--1.1 mm, gregarious or prostrate, growing in mats or singly among other
bryophytes. Stems 130--186 µm in diameter, with slight cortical
differentiation, cortex and
medulla 8--9 cells in width, cortical cells in transverse section 17--22 x
16--24 µm; flagelliform branches common. Leaves suborbicular to broadly ovate
with apex rounded (occasionally moderately emarginate), moderately imbricate,
strongly concave, 282--690 x 389--516 µm; cuticle slightly papillose. Leaf
cells at margins 13--24 x 8--18 µm; at midleaf 12--26 x 13--29 µm, at
base 18--31 x 27--34 µm; trigones small to large; oil bodies (1--)2--6(--8)
per cell, 5--16(--19) µm. Underleaves
distant, 75--209 x 65--125 µm, cells 14--23 µm. Specialized asexual reproduction
gemmae common, forming at the tips of ascending shoots, orbicular to ovate to
elliptic, 1--2 cells, 25--35 µm. Androecia
bracts 0.3--0.3 x 0.1--0.2 mm. Gynoecia bracts 0.9--1.1 mm. Perianth
2.5--4.0 x 0.5--1.0 mm; cylindrical;
mouth crenulate. Sporophyte capsule wall of 2 cell layers; 30--65 µm in thickness outer
cells 17--41 µm in width; inner cells 11--22 µm in width. Elaters
105--256 x 10--11 µm, 2-spiraled. Spores 8--11(--15) µm. Subspecies 3 (1
in the flora) 1a. Odontoschisma denudatum (Nees) Dumort. ssp. denudatum Odontoschisma
denudatum var. laevissima R. M. Schuster; O. gibbsiae A. Evans Leaves ovate to
suborbicular, concave, and straight in stance, never curved or subfalcate. Temperate and
boreal, mesic sites, also sites of low pH, moist decaying logs and peaty soils
in moorlands, heaths, rocky slopes, and bogs; low to high elevations; St. Pierre and
Miquelon; B.C., N.B., Nfld. and Labr. (Nfld.), N.S., Ont., Que.; Ala., Ark.,
Conn., Del., D.C., Fla., Ga., Ky., La., Maine, Md., Mass., Mich., Minn.,
Miss., N.H., N.J., N.Y., N.C., Ohio, Pa., S.C., Tenn., Vt., Va., W.Va., Wis.;
Mexico; West Indies; Central America; South America; Europe; Asia; Pacific Islands. Schuster (1974)
indicated that the reports of O.
denudatum ssp. denudatum to
Greenland are erroneous due to confusion with O. elongatum. We also treat those records as
erroneous. Gradstein and Ilkiu-Borges
(2015) provide little information as to why O. denudatum var. laevissima
was placed in synonymy with O.
denudatum ssp. denudatum other
than stating that, based on the
original description of O. denudatum
var. laevissima and topotype
material, it is conspecific with O.
denudatum ssp. denudatum. Additionally, Gradstein and Ilkiu-Borges
(2015) provide no information for synonymizing O. gibbsiae with O. denudatum
ssp. denudatum; however, Godfrey
(1977) indicated that the difference in leaf stance, degree of leaf
imbrication, underleaf stance and gemmae anatomy fell within the
circumscription of O. denudatum and
hence indicated the synonomy. After
examining the type material of O.
gibbsiae (YPM) we support hypothesis that O. gibbsiae is conspecific with O. denudatum ssp. denudatum,
as the leaves are not emarginate or lobed, the leaf margins lack thick-walled
marginal cells, and the cells of the leaves lack a deeply pigmented middle
lamella. |
