Protologue Description: Orthotrichum kellmanii Norris, Shevock, & Goffinet sp. nov.(Fig. 1). TYPE: USA, California: Santa Cruz Co.:Near Basin Trail and China Grade about 1.5 miles north of Highway 236, Big Basin Redwoods State Park, 37º 12'40" N; 122º 12'42"W, Elev: 685 m, 21 Jan 2001, Kellman 1251. Holotype CAS; isotypes: CONN, H, MO, NY, UC. Paratypes: USA, California: San Mateo Co.:Butano Fire Road about 0.25 mile beyond the Boy Scout Camp, Big Basin Redwoods State Park, 37º 12'44"N. 122º 14'41"W, Elev: 650 m, 25 Feb 2001, Kellman 1325 (CAS).)

Planta subaladocarpa, axe sporophytico distincte altiore quam gametophytico. Folia et perichaetialia et subperichaetialia lanceolata, vegetativa elliptica, perbrevioria. Sporophyton immersum maturitate sulcatum; dentes exostomiales valde cribosi, in aspectu ut videtur 32; endostomium fagax, breve.

Plants in dark green to almost black in low and tangled crescent-shaped mats with prostrate and microphyllous axes from which arise short vegetative axes strongly overtopped by the very different high fertile axes. Main axes to 30 mm long with vegetative axes to 2 mm high and with sporophyte-bearing axes to 10 mm high. Leaves of vegetative axes spreading to erect-spreading, often with inflexed apices when moist but closely appressed when dry, elliptic to somewhat ligulate, broadest near mid-leaf, with obtuse to broadly rounded apices, to 1.4 mm long, about 4: 1. Leaves strongly keeled in proximal 1/2 but essentially without a keel distally. Median laminal cells bistratose throughout, low papillose with papillae salients about 1/8 of lumen depth, 10-12 µm wide, arranged in regular rows, isodiametric with rounded lumens. Lumens of the median cells rounded due to the strong corner thickenings. Basal marginal cells to 10 µm wide, quadrate to short rectangular with thin walls and without significant porosity, pellucid and smooth or papillose, not conspicuously auriculate at immediate base. Basal juxtacostal cells smooth, short-rectangular with oblique end-walls, neither strongly incrassate nor porose, with lumen: wall ratio more than 6: 1, to 10 µm wide, 2-3: 1, pale to hyaline. Cells on adaxial surface of costa similar to adjacent laminal cells or more nearly smooth. Margins entire to crenulate, often somewhat erose, usually recurved on at least a portion of one side. Costa placed in a deep channel almost throughout, ending within a few cells of apex. Costa cross section 3 cells thick, with up to 10 on abaxial but only 2-4 of adaxial surface, without stereids, less than twice as thick as the adjacent lamina. Leaves of sporophyte-bearing axes rigidly erect when moist or dry, ovate-lanceolate to broadly lanceolate, broadest near the base, with acuminate apices, to 2.5 mm long, about 3.5-4.5: 1. Axillary hairs inserted near costa uniformly hyaline with bulging lateral walls, not at all offset from leaf insertion, to 8 cells and 200 µm long, mostly of similar size and shape throughout but with basal cell of narrowed diameter. Axillary hairs lateral to costa insertion somewhat shorter than those of median insertion. Rhizoids arising from adaxial lines of leaf insertion, brown to red-brown, densely produced at base of plant, to 15 µm in diameter at insertion, smooth and pachydermous with lumen: wall ratio nearly 1; 1, sparingly to rather closely branched. Stem cross-section rounded pentagonal, without a central strand, mostly with leptodermous and hyaline inner corticals and with almost no differentiation of an outer stereome. Autoicous with perigonia obvious as golden-brown buds in leaf axils close to the perichaetia. Perichaetial bracts only gradually differentiated from vegetative leaves of sporophyte- bearing axis, closely sheathing capsule, to 3.5 mm long, elliptic-lanceolate, about 4: 1, acuminate distally. Capsule basally only gradually expanded from the yellow to yellow-brown seta, immersed on a yellow to yellow brown, with seta smooth and rigidly erect, to 1 mm long. Urn pale-brown, to 1.5 mm long, 2.5-3.5: 1, erect, sulcate with 8 ribs when dry and old, not strangulate. Operculum conic-apiculate to very short rostrate. Annulus falling in fragments. Outer exothecial cells in cross-section mammillose-bulging with outer and transverse cell walls very thick but with inner wall thin and collapsing. Exothecial cells at capsule mouth to 12 µm wide, quadrate to transversely elongate, highly incrassate with angular lumens in 5-8 rows. Exothecial cells at middle of urn in regular rows, short rectangular to isodiametric, 1-2: 1, to 35 µm broad, with thin-walls and with transverse walls mostly oblique. Stomata cryptoporous, abundant on proximal 1/2 of urn, with subsidiary cells well-defined. Exostome teeth inserted somewhat below mouth of capsule, narrowly triangular, erect to weakly spreading when dry, so deeply cribrose as to appear on casual observation as numbering 32, pale to light brown, to 200 µm long, densely spiculate-papillose. Endostome segments shorter than exostome and often difficult to locate, nearly smooth, of only one row of cells. Calyptra with constituent cells smooth, strongly plicate, campanulate and sheathing all of capsule, sparsely covered with papillose hairs. Spores somewhat bimodal in size with largest ones to 12 µm but smallest to 8 µm, lightly papillose.