|
BFNA Title: Jamesoniella |
|
ADELANTHACEAE Grolle Marie L. Hicks Jamesoniellaceae He-Nygrén, Juslen, Ahonen, Glenny &
Piippo Plants forming mats;
branches usually replacing ventral half of a leaf
[intercalary from underside of stem]; without flagella [ventral flagella present]. Leaves alternate [opposite], succubous, plane, unlobed
or retuse, entire; underleaves minute or absent, unlobed. Rhizoids scattered over ventral stem, more frequent near leaves and underleaves.
Specialized asexual reproduction absent. Gynoecium terminal on an ordinary leafy branch [on a short
ventral branch]. Perianth with or without
well-developed subfloral branches, perianth cylindrical, narrowed to mouth;
perigynium absent. Genera five,
species ca. 50 (one genus and one species in the flora): North America, Mexico, Central America, South America, Europe, Asia, Africa, Australia, Pacific Islands (New Zealand). Adelanthaceae is a small, mostly
tropical family that is sometimes split in two, with the species of the flora falling into the segregate Jamesoniellaceae. Feldberg et al. (2010a, b) gave reasons for keeping a single
family. SELECTED REFERENCES. Feldberg, K., J. Vána, D. G. Long, A. J. Shaw, J. Hentschel, and J. Heinrichs. 2010a. A phylogeny of Adelanthaceae (Jungermanniales,
Marchantiophyta) based on nuclear
and chloroplast DNA markers, with comments on classification, cryptic speciation and biogeography. Mol. Phylog. Evol. 55: 293--304. Feldberg, K., J. Vána, J. Hentschel, and J. Heinrichs. 2010b. Currently accepted species and new combinations in Jamesonielloideae (Adelanthaceae, Jungermanniales). Cryptogamie. Bryologie 31: 141--146. 1. SYZYGIELLA Spruce, J. Bot. 14: 234.
1876 Crossogyna (R. M. Schuster) Schljakov; Jamesoniella (Spruce)
Carrington Plants often with deep
red or red-brown pigmentation. Branches usually replacing ventral half of a leaf (base of branch paired with a lanceolate half-leaf), seldom intercalary from side of stem. Leaves unlobed
and entire; underleaves small or absent. Gynoecium with bracts ciliate-dentate to laciniate [entire]; perianth inflated, distally (3--)4--5(--6)-plicate, mouth ciliate to laciniate [entire]. Capsule wall 4--5 cells thick. Species ca. 30 (one species
in the flora): tropical and temperate areas of North America, Mexico, Central America, South America, Europe, Asia, Africa, Australia, Pacific Islands (New
Zealand). Sterile plants
of Syzygiella autumnalis superficially resemble Liochlaena and Jungermannia species, and it has been erroneously placed in Jungermanniacae in the past. It is easily recognized when fruiting by the dentate to laciniate bracts and bracteole, not found in other entire-leaved genera in the flora.
Syzygiella autumnalis is morphologically anomalous in the genus---the bulk
of the species are tropical, and have ascending, little-branched stems forming deep tufts. 1. Syzygiella autumnalis (De Candolle) K. Feldberg, Váňa, Hentschel &
Heinrichs, Cryptog. Bryol.
31: 144. 2010 Jungermannia autumnalis De Candolle, Fl. Franç. (ed. 3) 6: 202. 1815; Jamesoniella autumnalis (De Candolle) Stephani, Crossogyna autumnalis (De Candolle) Schljakov Plants with shoots
10--30 x 1.5--2.5
mm, prostrate, forming patches or thick mats, green to reddish brown; branches few. Stems stout, ca. 250--300 \um;
cortical cells thin-walled, 25--30 \um,
medullary cells similar with slightly thicker walls. Leaves imbricate, widely spreading, ovate to rounded-quadrate, 950--1100 x 950--1150 \um, the apex rounded to slightly retuse; leaf cell lumen rounded, sub-quadrate to hexagonal, median cells 25--35 x 28--40
\um; marginal cells slightly
smaller, ca. 22--25 \um; cuticle slightly verruculose-striolate near leaf base; cell walls thin, trigones with concave
sides, not bulging; oil bodies 7--15 per cell, ovoid to ellipsoidal, 3--5 x 5--9 \um, finely granular. Underleaves absent or occasional and subulate near stem apex. Androecia terminal, spicate, eventually becoming intercalary; bracts in 4--6 pairs, imbricate, slightly smaller than leaves, the dorsal
base ampliate with 1--2 inrolled teeth; antheridium one per bract; stalk 2-seriate. Gynoecia terminal on main shoot with 1--2 subfloral innovations; bracts larger than leaves, 1--1.2 x 0.9--1.2 mm, sheathing at base, spreading distally, rounded to retuse with 1--2 laciniate teeth or cilia on lateral
margins, the base narrowly connate with bracteole; bracteole large, 0.3--0.4 mm with several
laciniate-ciliate lobes; perianth cylindrical to fusiform, 3--3.5 mm, distal portion 4--5 plicate, narrowed to laciniate-ciliate mouth, cilia 5--10 cells long. Humus-rich soil, rock, logs or tree bases in moist temperate deciduous or Spruce-fir forests; low
to high elevations; Alta;
B.C. N.B., Nfld., N.S., Ont. Que.; Alaska, Conn, Fla., Idaho, Ill., Ind., Iowa.,
Kans., Ky., Maine, Md., Mass., Mich., Minn., Miss., Mo., N.H., N.J., N.Y., N.C., Ohio, Ore., Pa.,
R.I., S.C., Tenn., Vt., Va., Wash., W.Va., Wis., Wyo.; Mexico; Europe; Asia. Two segregates described from single sites in Nova Scotia probably do not merit taxonomic
recognition. Jamesoniella heterostipa A. Evans (J. autumnalis var. heterostipa (A. Evans)
Frye & L. Clark) was described from a
plant with exceptionally large underleaves, growing in a stream,, while J. myriocarpa Brinkman (= J. autumnalis var. myriocarpa (Brinkman) Frye & L. Clark) is
inadequately characterized. In addition, the Asian Syzygiella nipponica (S. Hattori) K. Feldberg,
Vána, Hentschel & Heinrichs was reported from a site in Virginia
by R. M. Schuster (1969) (as J. autumnalis var. nipponica (S. Hattori) S. Hattori). It seems more likely that this was an aberrant
plant of S. autumnalis. Syzygiella autumnalis is subject to environmental variation and the
differences on which these three variants were based are poorly understood. These plants are most
likely environmental variants. Additional literature Schuster, R. M. 1969. The Hepaticae and Anthocerotae of North America east of the hundredth meridian. Vol. 2. Columbia University Press,
New York. |
|
|
