Philonotis Bridel, 1827

NEEDS GENUS PARAGRAPH

Key to Philonotis Etc.

Mosses included in this section are costate acrocarps with short rectangular cells that are prorate distally or proximally. They have a dense coating of red-brown rhizoids that arise from macronematal apparati on older portions of the stems. Most of these plants grow on very moist soil of seepages or in bogs and fens.

Species included are in Bartramiaceae:
Conostomum tetragonum (Hedwig) Lindberg
Philonotis americana (Dismier) Dismier
Philonotis caespitosa Juratzka
Philonotis calcarea (Bruch & W. P. Schimper) W. P. Schimper
Philonotis capillaris Lindberg
Philonotis fontana (Hedwig) Bridel
Philonotis marchica (Hedwig) Bridel
Philonotis muhlenbergii (Schwägrichen) Bridel
Philonotis tomentella Molendo in Lorentz
Philonotis uncinata (Schwägrichen) Bridel, not known from CA
Philonotis yezoana Bescherelle & Cardot

Identification of Philonotis requires a view of the abaxial surface of the leaf. A whole mount of a leafy stem often serves this need. One wishes to see the prorate-papillosity from a side view on leaves seen in profile. Additionally, one should look down vertically on an excised leaf under the compound microscope. Note that the distal or proximal positioning of the prorations on Philonotis leaves is based upon a view from the abaxial surface

A. Abaxial surfaces of median leaf cells smooth or prorate on distal ends .....B
A. Abaxial surfaces of median leaf cells prorate on proximal ends or papillose over lumen .....F

B. Leaves glaucous, obviously pentastichous; costa of lower leaves ending before the apex .....Conostomum: C. tetragonum
B. Leaves green to pale green, unranked or obscurely pentastichous; costa of all leaves percurrent to excurrent .....C

C. Costa percurrent; perigonia broader than the diameter of the stem with perigonial leaves spreading .....Philonotis muhlenbergii
C. Costa excurrent by at least a few cells; perigonia various .....D

D. Leaf margins plane; costa long-excurrent with the awn on the most distal leaves about 1/4 of laminal length; distal cells of lamina mostly less than 4:1 .....Philonotis capillaris
D. Leaf margins recurved to revolute; costa excurrent but shorter; distal cells of lamina mostly longer than 4:1 .....E

E. Perigonia broader than the diameter of the stem with perigonial leaves spreading; leaves mostly more than 1.5 mm long .....Philonotis marchica
E. Perigonia smaller than the diameter of the stem with perigonial leaves erect; leaves mostly less than 1.5 mm long .....Philonotis uncinata not known from CA

F. Margins plane; leaves not plicate .....Philonotis caespitosa
F. Margins recurved at least at base; leaves lightly plicate near base .....G

G. Leaves pentastichous, inserted on stem at more than a 30 angle, twisted around stem when dry .....Philonotis americana
G. Leaves imbricate, not twisted .....H

H. Leaf cells with central papillae .....Philonotis yezoana
H. Leaf cells prorate to nearly smooth .....I

I. Leaves mostly more than 2 mm long with costa more than 250 µm wide; cells at mid-leaf near costa with lumen:wall ratio more than 4:1; perigonial bracts acute .....Philonotis calcarea
I. Leaves mostly less than 1.5 mm long with costa more narrow; cells at mid-leaf near costa with lumen: wall ratio less than 2.5:1; perigonial bracts obtuse or broadly acute .....J

J. Leaves ovate; costa hardly excurrent .....Philonotis fontana
J. Leaves narrowly lanceolate to ovate-lanceolate; costa strongly excurrent .....Philonotis tomentella