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BFNA Title: Herbertaceae |
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Herbertus –
Herbertaceae XX. HERBERTACEAE
Müller Frib. ex Fulford &
Hatcher W. B. Schofield Herbertus Gray, Natur. Arrang. Brit. Pl. 1:705.
1821 Plants usually
robust and rigid, 1--25 cm in secondary branch system in which branches are occasionally
lateral, but mainly postical from underleaves. Leaves
incubous to nearly transverse, asymmetrically to symmetrically 2- or 3-lobed,
lobes narrowly lanceolate to broadly triangular, usually deeply divided;
underleaves symmetrical and transversely attached. Specialized asexual reproduction absent. Sexual condition dioicous; androecia terminal initially but subterminal
with growth of androecial shoot, antheridia in axils of both lateral and
underleaves; perianth terminal, oblong-fusiform, 3--6 plicate, apex divided
into 6--9 lobes. Genera 2 (1 in
flora): circumtropical: North
America, South America, Europe, Asia, Africa, Australia, Pacific
Islands. The
Herbertaceae is predominantly epiphytic, but is also found on soil and
cliffs. The family extends northward to Arctic and subarctic regions and
southward to subantarctic regions, in elevations from near sea-level to above
3000 m SELECTED
REFERENCES: Evans. A. W. 1917. Notes on the genus Herberta, with a revision of the species known from Europe, Canada
and the United States. Bull. Torrey
Bot. Club 44: 191--222. Feldberg, K, H. Groth, R. Wilson, A. Schäfer-Verwimp and
J. Heinrichs. 2004. Cryptic speciation in Herbertus
(Herbertaceae, Jungermanniopsida): Range and morphology of H. sendtneri
inferred from nrITS sequences. Plant
Syst. Evol. 249: 247--261. Hodgetts,
N. G. 2003. Some synonyms of Herbertus dicranus (Taylor ex Gottsche et al.) Trevls. J. Bryology 25: 138--140. Hong W. S., B. Deffinbaugh and B.
Sparrow. 1993. The genus Herbertus in western North America. Lindbergia. 18: 41--45. Inoue, H. 1977. Studies in Taiwan Hepaticae II. Herbertaceae. Bull. Nat. Sci. Mus. (Tokyo) ser B. (Bot)
3: 1--11. Reenen, G. B. A. van. 1982.
Studies in Colombian cryptograms. XII: High Andean species of Herbertus S. F. Gray (Hepaticae). Lindbergia 8: 110--120. Schuster, R. M. 1957. Notes on nearatic
Hepaticae XV. Herberta. Rev. Bryol.
Lichénol. 26: 123--145. 1. HERBERTUS
Gray, Natur. Arrang. Brit. Pl. 1: 705. 1821
* [For G. Herbert a patron of Pier’Antonio
Micheli, 1679--1737] Plants beginning
as a rhizomatous irregularly branched system with rhizoids arising mainly
from underleaves, with leaves lacking well-defined vitta, this system
disappearing into the persistent secondary system in which the plants are
small to robust, rusty to reddish brown, 2--25 cm, suberect to pendulous,
forming moss-like turfs or rounded cushions of sparsely irregularly branched
stems, postical flagelliferous branches occasional to frequent. Stems
rigid to soft, often brittle. Leaves in 3 rows, the ventral smaller
than the two lateral, equally to somewhat unequally 2-fid, usually with
apparent forked vitta, incubously inserted, imbricate to somewhat postically
secund and falcate or straight; base of leaf sometimes auriculate; trigones
large, sometimes nearly confluent; rhizoids mainly confined to rhizomatous
stems that precede the appearance of main shoots, occasionally at the bases
of underleaves; oil
bodies 4--15+, homogeneous. Specialized
asexual structures absent, some plant parts fragile. Sexual
condition dioicous; archegonia surrounded by a catkin-like plicate
perianth with laciniate mouth on short lateral branches when mature. Sporophyte
barely emergent from perianth; sporangium subspherical, with 4--7 stratose
wall, dividing regularly into 4 valves or irregularly. Spores
spherical. Species ca. 30 (3 in flora): nearly worldwide, circumtropical, also
interruptedly circumtemperate in both the northern
and southern hemisphere, extending to low Arctic and low Antarctic, also
islands in the Atlantic and the Pacific. The key to
species is based on presence of persistent secondary branches. 1. Lateral
leaves deeply 2-lobed to 2/3 leaf length, with lobes narrowly lanceolate,
leaf not strongly bulging at base . . . 1. Herbertus aduncus 1. Lateral
leaves 2-lobed 1/3--1/2 leaf length, with lobes broadly triangular to broadly
lanceolate, leaf strongly bulging at base, especially on antical side. 2.
Leaves nearly as broad as long, 2-lobed 1/3 or less leaf length; lobes
broadly triangular, decidedly asymmetric . . . Herbertus sendtneri 2.
Leaves 2 times as long as broad, 2-lobed 1/2 leaf length, base often bulging
outward, lobes lanceolate, symmetric or asymmetric . . . Herbertus dicranus 1. Herbertus
aduncus (Dickson)
Gray, Nat. Arr. Brit. Pl. 1: 705. 1821 Jungermannia adunca Dickson, Plant. Crypt. Fasc. 3: 12, plate 8,
fig. 8. 1793 Plants brownish to
red-brown, sometimes dark green or wine-red, in polsters or turfs. Stems
erect to reclining, sometimes unbranched or irregularly few-branched, but
sometimes with numerous flagelliferous postical branches, main stems 1--10
cm. Leaves deeply asymmetrically or symmetrically 2-lobed with lobes
narrow, 4--7 times as long as wide, vitta strong, extending to middle of leaf
or beyond, of elongate cells, leaves imbricate to secund postically,
occasionally somewhat squarrose. Sexual condition dioicous; androecia intercalary, perigonial leaves
less deeply lobed than most leaves, not falcate; gynoecia terminal, with innovations,
becoming lateral with continued growth; perianth ovate, narrowed to mouth,
divided into 6 lanceolate lobes. Capsules
mature summer, confined to epiphytic
populations. Commonly epiphytic, also terrestrial or cliffs; forests
and peatland, 0--1000 m; Alta., B.C.; Alaska, Oreg., Wash. Herbertus aduncus is also found in southeastern Asia (as
subsp. schusteri H.A. Miller &
G. Scott, and in western Europe (as subsp. hutchinsiae (Gottsche) Schuster, but these subspecies are weakly
distinguished, as is subsp. tenuis. Indeed, the literature concerning these
variants is extremely confusing, generated by polymorphism. In North America, sporophytes are known
only from the west coast, and even then they are confined to epiphytic
material and are not frequent except near the open coast. In consequence, clones are probably
frequent, and the eastern North American material presumably represents a
clone. Isolation modifies color,
stature, deepness of lobing and even the abundance of flagelliferous
branches. 1. Leaf bases
smooth-margined except for sessile slime-papillae. .
. 1a. Herbertus aduncus subsp. aduncus 1. Leaf bases
frequently with stalked slime papillae or with teeth terminated by a slime
papilla . . .1b. Herbertus
aduncus subsp. tenuis 1a. Herbertus aduncus subsp. aduncus Plants commonly
rusty brown, slender, 1--13 cm, in tall, forming turfs or cushions. Stems unbranched
or few branched, except for postical flagelliferous branches. Lateral leaves erect and nearly
symmetric to asymmetric and secund, deeply divided with a narrow V-shaped
sinus; vitta forked and apparent, not extending to apices of lobes. Sporophytes
occasional on epiphytic plants, maturing late spring--early summer. Commonly
epiphytic, but also terrestrial in peatland, talus slopes, cliffs, mainly
near the coast; 0--1000 m; Alta., B.C.; Alaska, Oregon. Subspecies aduncus is endemic
to Pacific North America. It is relatively easy to determine in the
field. Terrestrial plants can be
confused with H. dicranus, but the latter species usually has bulging
auricles and the lobes of lateral leaves are nearly as wide as long with the
sinus more U-shaped than V-shaped. 1b. Herbertus aduncus subsp. tenuis (A. Evans) Miller & Scott Herberta tenuis A. Evans, Bull. Torrey Bot. Club 44: 219. 1917 Plants slender, yellow- to brownish green,
rarely vinaceous, forming mats of suberect stems 0.5--4 cm deep, stems
unbranched or irregularly and sparingly branched, 0.5 mm in diameter (or
less), of somewhat thick-walled cells.
Leaves 0.9--1 mm, with narrow
but divergent lobes from a V-shaped sinus 2/3--3/4 length of leaf, slightly
or not curved, long-acuminate 0.6--0.7 x 0.15--0.17 mm, sometimes with basal
teeth and slime papillae; vitta extending well into lobes, but never to apex. Specialized
asexual reproduction by brittle leaf lobes. Sporophytes unknown,
only female plants known. Mainly on
cliffs, shaded walls and ledges, also epiphytic on tree trunks; low to high
elevations (0 m in Nfld. but mainly above 2900 m); Nfld. and Labr. (Nfld.); Ga., N.C., N.J.,
N.Y., Penn., S.C., Tenn., Va., W.Va. Subspecies tenuis is endemic to eastern North
America and might be confused with occasional specimens of subsp. aduncus
from western North America, but tends to be considerably smaller and more
slender than that taxon. 2. Herbertus
dicranus (Taylor) Trevisan, Mem. Real. Inst. Lombardo Sci. Lett. Class.
Sci. Mat. Nat., Sec. 3,
4: 397. 1877 Sendtnera dicrana Taylor, Syn. Hep., 239. 1845; H. sakuraii
subsp. arcticus Inoue & Steere Plants in tall or short, loose or tight turfs
of erect to suberect shoots, also as polsters, 1--20 cm, rusty brown to
occasionally vinaceous or nearly black.
Stems unbranched to irregularly or densely branched, especially with
flagelliferous postical branches. Leaves asymmetrically lobed, usually
closely imbricate, falcate-secund postically, especially on main shoots,
almost transversely inserted, 2--3 times as long as wide, with lobes 1/2 or
less of leaf length, broadly lanceolate, leaf base on antical side usually
bulging to nearly auriculate, often with marginal downward pointing teeth and
slime papillae, vita extending 2/3 length of lobes, cuticle smooth. Specialized
asexual reproduction via brittle shoots.
Sexual condition diocous. Sporophytes unknown
in North America. Mainly terrestrial or on cliffs in North America but
epiphytic elsewhere, in hyperoceanic climates in open coniferous forests,
peatland and on cliffs; 0--500 m;
B.C.; Alaska, Oreg., Wash.; Asia; Africa (?); Pacific Islands. Included here
as H. dicranus are North American specimens determined as H.
himalayanus (Stephani) Herzog, H. sakuraii (Warnstorf) Hattori and
H. hawaiiensis H. Miller. Herbertus
dicranus shows extreme variability throughout its range, with the
material from Arctic Alaska and interior northern B.C. (as H. sakuraii subsp. arcticus) distinctive in its small size, shallowly lobed leaves
and alpine restriction. Specimens from
peatland and open hyperoceanic forest can be unusually large (to more than 20
cm), form an extensive loose turf, and show considerable flagelliferous
branching. Material of open sites is usually little branched, and varies from
rusty red-brown to nearly black. The Oregon population (Saddle Mt.) is
smaller than most material other than that of Arctic and alpine sites, but intergrades
with material elsewhere. Some
specimens throughout the range resemble H.
stramineus (Dumortier) Trevisan of Europe. 3. Herbertus sendtneri (Nees) A. Evans, Bull. Torrey Bot.
Club. 44: 212. 1915 Schisma sendtneri Nees, Naturg. Eur. Leberm. 3: 575.
1838 Plants in loose
turfs or as isolated shoots, yellow-green to brown, stems 6--10+ cm,
unbranched or with occasional postical flagelliferous branches, leaves
crowded. Leaves somewhat postically secund, 1--1.5 mm, broadly ovate with
broad lobes and sinus 1/3 or less the leaf length, and the leaves only
slightly longer than wide, symmetrically or asymmetrically lobed; underleaves smaller, more shallowly
and symmetrically 2-lobed; lobes are wider than long and thus broadly
triangular. Sporophytes unknown.
Terrestrial, shaded cliffs, shaded sites in tundra; 10--2000 m; B.C.; Alaska;
Europe (Alps); Asia (Himalayas). Herbertus sendtneri is readily determined in the field in
most instances, but there are morphs of both the other species that can resemble
it in size and lobation. This species occurs mainly near the coast, and may
be alpine or subalpine, but only to 800 m in its southern range, and
extending lower to ca. 10 m in the Aleutian Islands. K. H. Feldberg et al. (2004) place material named as H. subdentatus
(Stephani) Fulford into H. sendtneri, but state that it is not
identical with it. Until this is
resolved H. sendtneri is treated as North Temperate in distribution. |