Bazzania nudicaulis A. Evans
Family: Lepidoziaceae
Synonyms
none
NatureServe Conservation Status
G2G3
Distribution
Endemic to the Southern Appalachians. North Carolina, Tennessee, Virginia.
Although accepted as occurring in New York by Duncan and Slack (2017), notably without comment for such an exceptional expansion of the known range, we exclude New York from the distribution. The New York occurrence is based on a single specimen that we have not seen, Cutler, L. M. s.n., 22 Aug. 1971 (NYS).
Habitat
"Occurring only on the fog-shrouded summits of the highest peaks of the Appalachian system; rare below 5500 feet" (Schuster 1969, p. 81). Essentially limited to Fraser fir - red spruce forests and high elevation rocky summits with scattered occurrences in northern hardwood forests mostly above 5000 ft. Occurring on rock and the bark of Abies fraseri, Betula alleghaniensis, Picea rubens, Prunus pennsylvanica, and Sorbus americana (Davison et al. 1999). Also on humus over rock; occurrences on humus “appear restricted to exposed lofty mountain cliffs” (Schuster 1969, p. 82). High elevations (5000 – 6600 ft; lowest elevation, if correct, is listed in Schuster [1969, p. 81] as "Mt. LeConte, 4500 and 6590 ft (Sharp)").
On trees and rocks B. nudicaulis may occur with the following liverworts: Frullania asagrayana, Herbertus tenuis, Leptoscyphus cuneifolius, Microlejeunea ulicina, Plagiochila exigua, and Sphenolobopsis pearsonii; on rock B. tricrenata may be admixed (Schuster 1969).
Brief Description and Tips for Identification
Description from Fulford (1936) and Schuster (1969). Forming pendulous tufts or scattered over other bryophytes, brownish, rarely almost black. Individual shoots up to 1.5 mm wide, usually smaller. Shoots with two types of branches, 1) lateral, leafy branches and 2) ventral, flagelliform branches. Lateral leaves ovate-lanceolate with apices deflexed. Underleaves quadrate-orbicular, as wide as long and 2-3 times as wide as the stem. Lateral leaves and underleaves frequently caducous. Oil bodies (1)2-3(4) in cells of lateral leaves.
Dioicous? Sex organs unknown. Asexual reproduction by means of caducous leaves and underleaves.
Four species of Bazzania occur in the Southern Appalachians: B. denudata, B. nudicaulis, B. tricrenata, and B. trilobata. B. trilobata is the most common and robust species and is not likely to be confused with B. nudicaulis. B. trilobata, like B. denudata, lacks the deflexed leaf tips and brownish coloration typical of B. nudicaulis. B. trilobata and B. denudata also have a higher number of oil bodies (4-8) in cells of the lateral leaves. B. denudata does freely produce caducous leaves but the green color and higher oil body number prevent any confusion.
Differentiating B. tricrenata is more difficult. The two species share a similar size, brownish coloration, deflexed leaf tips, and low number of oil bodies per leaf cell [(1)2-3(4) oil bodies in B. nudicaulis, 2-4(5) in B. tricrenata, Schuster (1969). Paton (1999) described B. tricrenata with (1)2-6(8) oil bodies]. The two may occur together on shaded, damp rocks, but B. tricrenata fails to colonize the bark of trees well above the ground as typical of B. nudicaulis. Morphologically, the species differ in that B. tricrenata does not produce caducous leaves and, most critically, has underleaves wider than long and only 1.5 times as wide as the stem. B. nudicaulis underleaves are as long as wide and 2-3 times as wide as the stem.
Salient Features
- Caducous leaves and underleaves
- Underleaves as long as wide, 2-3 times as wide as stem
- Brownish color
- Deflexed lateral leaf apices
- Oil bodies (1)2-3(4) in cells of lateral leaves
References
Davison, P. G., McFarland, K. D., and Smith, D. K. 1999. RTE bryophyte survey of southern Appalachian Fraser fir forests, North Carolina, Tennessee, Virginia. Prepared for Natural Heritage Programs, North Carolina and Tennessee
Duncan, B., and Slack, N. G. 2017. New York State liverworts and hornworts: a distributional checklist by counties. Evansia, 34(3), 114-133.
Evans, A. W. 1923. Notes on North American Hepaticae. X. The Bryologist, 26(6), 55-67
Fulford, M. 1936. The genus Bazzania in the United States and Canada. American Midland Naturalist, 17(2), 385-424.
Paton, J.A. 1999. The Liverwort Flora of the British Isles. Harley Books, Martins, England
Schuster, R.M. 1969. The Hepaticae and Anthocerotae of North America East of the Hundredth Meridian. Volume II. Columbia University Press, New York
Schuster, R.M. 1980. The Hepaticae and Anthocerotae of North America East of the Hundredth Meridian. Volume IV. Columbia University Press, New York
Habitat
Bazzania nudicaulis
Abundant on a large fir near Clingmans Dome in 2018.
Bazzania nudicaulis
A large patch on a fir on Roan Mountain, 2018
Bazzania nudicaulis
On a small tree on Roan Mountain, 2018
Habit
Bazzania nudicaulis
Forming brownish tufts on a small fir on Roan Mountain, 2018
Bazzania nudicaulis
Pendent tuft on a fir tree on Clingmans Dome, 2018.
Bazzania nudicaulis
At this scale, one can't be sure that Leptoscyphus and/or Sphenolobopsis aren't admixed.
Habit
Bazzania nudicaulis
Denuded stem sectors remain following detachment of caducous leaves
Bazzania nudicaulis
A single green shoot of the liverwort Tritomaria is at the far right, upper half of the image.
Bazzania nudicaulis
The much larger liverwort Frullania asagrayana is admixed.
Morphology
Bazzania nudicaulis
Arrows point to flagelliform, ventral braches bearing reduced leaves.
Bazzania nudicaulis
Apices of lateral leaves may bear 2 or 3 teeth, or the apex is merely acute.
Bazzania nudicaulis
Dorsal aspect. Panels 1, 2, and 3 showing variation in the number of teeth at the leaf apex. The unnumbered panel shows deflexed leaf tips.
Morphology
Bazzania nudicaulis
Underleaves are at least as long as they are wide and are much wider than the stem. Notice the missing underleaves in the far left and far right shoots. Both underleaves and lateral leaves may readily fall off and are thus described as caducous when doing so.
Bazzania nudicaulis
Oil bodies numbering 2-3 per leaf cell.
Bazzania nudicaulis
Leaf cells with oil bodies; a small form with lateral leaves reduced in size
Other Bazzania species
Bazzania tricrenata
Older herbarium specimens comparing B. tricrenata with B. nudicaulis in the dried state, dorsal view. B. tricrenata lacks caducous leaves.
Bazzania tricrenata
Underleaves are wider than long and usually not much wider than the stem. The absence of a lateral leaf below the scale bar is due to damage incurred in the fragile, dried state.
Bazzania tricrenata
Two ventral, flagelliform branches similar to those in other regional Bazzania species are shown projecting upwards. The image shows small underleaves and lateral leaves with deflexed leaf apices.
Other Bazzania species
Bazzania tricrenata
The larger underleaves shown are clearly wider than long.
Bazzania denudata
Oil bodies numbering 7-9 per cell. Color of plant is green, without any brownish pigmentation; denuded stem sectors due to caducous leaves.
Bazzania trilobata
Aptly dubbed the "millipede weed" by Allen Risk. Each of the closely overlapping leaves ends in three teeth as indicated for one leaf at the yellow arrowheads.
Similar Field Associates
Leptoscyphus cuneifolius
Given the brownish color, wiry stems, and its occurrence on trunks of Abies fraseri, L. cuneifolius is easily mistaken in the field for small forms of B. nudicaulis.
Leptoscyphus cuneifolius
As in B. nudicaulis leaves are freely caducous, yet the leaf shape is quite different being widest near the apex.
Similar Field Associates
Plagiochila exigua
Also with freely caducous leaves resulting in naked stems, the leaves of P. exigua (=P. corniculata in Schuster 1980) are more deeply bilobed than B. nudicaulis and underleaves are extremely small consisting of only a few cells and not likely to be seen except at 400x.
Plagiochila exigua
The species may occur on sheltered rock or trees along with B. nudicaulis. The above photo from a Fraser fir forest on Roan Mountain, 2018.
Similar Field Associates
Sphenolobopsis pearsonii
Relativey frequent on trunks of Fraser fir, S. pearsonii may occur as few strands admixed with B. nudicaulis or occur in relatively pure mats as shown above.
Sphenolobopsis pearsonii
The deeply bilobed leaves transversely inserted on the stem prevents any confusion with B. nudicaulis with which S. pearsonii may occur.