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XX. EREMONOTUS Lindberg
& Kaalas ex Pearson, Hep. Brit. Isles 200. 1900 * [Greek eremos isolated, deserted, and notos dampness, alluding to the
habitat] Anomomarsupella R. M. Schuster, Nova
Hedwigia 17: 78, pl. 10. 1969 Edwin Urmi Plants minute. Stems thin, in cross section with
only 15--18 firm-walled cells. Lateral
leaves transversely inserted, 2-lobed and concave (not plicate as often
stated); cells firm-walled, a few of them (irregularly arranged) with a
single very large oil body. Underleaves
reduced to a slime papilla. Asexual
reproduction lacking. Sexual
condition dioicous. Androecia
wider than vegetative parts. Gynoecia
with dorsiventrally flattened perianth. Sporophytes
rather massive compared with the gametophytes. Species 1 (1 in the flora);
Arctic North America, Arctic Eurasia. Selected
references: Damsholt,
K. 1977: The taxonomic status of Anomomarsupella
Schust., (Hepaticae). Lindbergia 4: 132. Hentschel, J., J. A. Paton, H.
Schneider, and J. Heinrichs. 2007: Acceptance of Liochlaena Nees and Solenostoma
Mitt., the systematic position of Eremonotus
Pearsson and notes on Jungermannia
L. s.l. (Jungermanniidae) based on chloroplast DNA sequence data. Pl. Syst.
Evol. 268: 147--157. Schuster, R. M. 1966--1992: The Hepaticae and
Anthocerotae of North America East of the Hundredth Meridian. 6 vol. New
York, London, Chicago (Anomomarsupella in
vol. 3, pp. 166--170). Urmi, E. 1978: Monographische Studien an Eremonotus myriocarpus (Carring.)
Pears. (Hepaticae). Bot. Jahrb. Syst., Pflanzengesch. Pflanzengeog. 99:
498--564. 1.
Eremonotus myriocarpus
(Carrington) Pearson, Hep. Brit. Isles 201. 1900 Jungermannia
myriocarpa Carrington,
in Carrington and Pearson (ed.), Hep. Brit. Exsicc. (fasc. 2) no. 96. 1879; Anomomarsupella cephalozielloides R.M.
Schuster Plants 2--8 x
(0.06--)0.10--0.15(--0.16) mm, sparingly branched, loosely creeping or
ascending from a stoloniform system in dense mats, from ocher or dark
greenish brown to nearly black (never reddish), somewhat shiny in dry state. Stems 50--75(--80) /um wide,
branching lateral intercalary from a single specialized cell in the axils of
lateral leaves (Eremonotus type of
branching); stems terete, in cross section with 8--10 epidermal and 7--9
central cells; few colourless rhizoids, more and irregularly arranged in the
creeping system. Lateral leaves mostly
well spaced, appressed or little spreading both wet and dry, concave, in situ
(90--)100--160(--180) x (60--)80--120(--130) /um, 2-fid to about the middle;
lobes equal, triangular and acute, their margins mostly entire; lobe cells
more or less quadrate in transverse
rows, the other less regular and somewhat larger, midleaf cells more or less
isodiametric (8--)12--16(--20) /um, surface verruculose, walls evenly thick;
oil bodies minute except for a single very large one in some irregularly
arranged cells. Ventral leaves vestigial,
consisting of 1 cell (a slime papilla). Androecia
becoming intercalary, width more than the double of vegetative parts and
somewhat dorsiventrally compressed, length and number of bracts indefinite,
bracts much larger and more pigmented than vegetative leaves, 2-fid, bulbous
and somewhat keeled near the insertion, bracteoles vestigial, 1 single large
antheridium, whitish and nearly spherical, with short biseriate stalk, body
ca. 120 /um in diameter, filling the whole venter of each bract. Gynoecia on long shoots, sometimes
with 1--2 innovations; lateral leaves gradually turning into 3 much larger
bracts, free from each other and canaliculate; bracteoles vestigial; perianth
longly exerted, (0.4--)0.5--0.6(--0.8) x 0.3 mm, rounded at the apex, with 1
dorsal and 2 ventral folds, mouth shortly 3-lobed and ciliate; 1-layered
troughout; with 3--7 archegonia and a few paraphyses. Seta often about 2 mm long and 0.14 mm wide, transverse section
with exactly 8 outer and 4 somewhat smaller inner cells. Capsule black and shiny, ellipsoid, dehiscing with 4 valves, wall
with 2 cell layers, outer layer with intermediate nodular, inner layer with
incomplete half-ring thickenings. Spores
brick-red, spheric, (12--)14--16(--18) /um, wall thin, faintly granulated;
elaters free, worm-like, ca. 100 x 7 /um, mostly with 2 spirals. Mostly on humid or wet
siliceous rock along streams in sheltered places; often together with Blepharostoma trichophyllum s.l., Solenostoma pumilum s.l., Odontoschisma macounii, Anthelia julacea
or Blindia acuta; low to moderate
elevations (50--1100 m); Greenland; B.C.; Alaska, Wash.; Arctic Eurasia. The distribution of Eremonotus myriocarpus in North America is poorly known, due to its
nondescript habit. It has often been mixed up with small Marsupella species, but is readily distinguished from these by
the lack of red pigments. |
