Monographs Details: Fissidens pseudopallidus I.G.Stone
Authority: Buck, William R. 1987. Bryostephane Steereana: A Collection of Bryological Papers Presented to William Campbell Steere On The Occasion of His 80th Birthday. Mem. New York Bot. Gard. 45: 1-749.
Family:Fissidentaceae
Description:Latin Diagnosis - F. sufflato similis, diflfert tamen apice folii acuto vel acuminato, cellulis laminae majoribus, margine laminae vaginantis 4-5 cellularum baud (vel minime) suflflatarum, seriebus valde incrassatis praedito, a F. pallido cellulis marginalibus laminae apicalis diflfert (vide Figs. 39-61). Holotypus: I. G. Stone 19744 (mel).

Species Description - Plants laxly gregarious, procumbent on gritty soil in semi-shaded rainforest often mixed with other bryophytes. Stems (Fig. 39) similar to those of F. sufflatus. Leaves (Figs. 40-42) lanceolate, to 3.4 mm long, 0.5-0.6 mm wide, pellucid, green often tinged with red, loosely curled to circinately colled at tips when dry; apex (Fig. 43) acuminate or acute; lamina unistratose often slightly rugose; vaginant laminae half or less the leaf length (rarely more), slightly unequal, the free lamina often a little wider than the fixed lamina and joining between the margin and costa; dorsal lamina (Fig. 44) usually narrower than in F. sufflatus, rounded or somewhat tapered at base of leaf, sometimes slightly decurrent; margins of apical and dorsal laminae (Figs. 43-47) entire to weakly undulate (except in acuminate tip where irregularly denticulate), thick, consisting of a band of 3-4 cell rows with intramarginal cells larger than the small marginal row, in cross section club-shaped, unistratose with swollen thick walled cells much deeper than the rest of the lamina cells; margin of vaginant lamina (Figs. 48-50) in surface view consisting of a band of 4-5 cell rows composed of very thickly walled smooth flat cells, in cross section of one layer with the lumina no larger than those of the lamina cells. Costa (Figs. 47, 49) subpercurrent, 60-80 µm wide at base tapering above to 30 µm, similar in structure to that of F. sufflatus but with more stereid layers in region of vaginant lamina. Cells of apical and dorsal laminae (Figs. 43-45) chlorophyllose, incrassate, irregularly hexagonal with rounded corners, mamillose or slightly so, mainly 10-15 µm diameter, in the acuminate apex elongated to 30 µm long and highly refractive, at base of dorsal lamina to 20 µm long, 12-15 µm wide. Dioicous. Male and female plants similar in habit to those ofF. sufflatus, antheridia longer, 450-500 µm long; seta (Fig. 51) longer, to about 8 mm, similar in transverse section; u m (Fig. 52) ca. 1.2 mm; exothecial cells (Fig. 53) often shorter, stomata round-pored (Fig. 54); operculum and calyptra (Fig. 55) similar; peristome teeth (Figs. 56-61) similar but bases of teeth often higher, to 160-180 µm above capsule mouth, arms ca. 200 µm long, ventral and dorsal plates with similar ornamentation to F. sufflatus. Spores green, faintly papillose 12-15 µm diameter.

Discussion:

Holotype: AUSTRALIA. Queensland: Mt. Haig, Danbulla State Forest, altitude ca. 1000 m, on gritty earth, semi-shaded road bank in rainforest, 2 Jul 1982, I. G. Stone 19744 (mel); isotypes will be lodged in bm, bri and melu.

Fissidens sufflatus and F. pseudopallidus have been found at several localities in the wet tropical rainforests of north Queensland between latitudes 17°25' and 16°07' S and longitudes 145°50' and 145°03' E, on soils derived from granitic rock or on granite rocks at altitudes between 200 m and 1600 m with an average annual rainfall of 2500 mm to 3750 mm. The two species are closely related but are suflficiently diflferent to be specifically distinct. They diflfer in leaf shape, length of vaginant lamina, cell size and particularly in the margin of the vaginant lamina which in F. sufflatus is swollen and thickened for 1-2 rows of cells, but in F. pseudopallidus is incrassate for 4-6 rows but not usually swollen, producing a broad pale border in surface view. There are also sporophytic diflferences mainly in dimensions of seta, urn and spores.

No other moss with similarly swollen marginal cells is known from Australia and when first collected it was thought the two species might be closely related to F. nitens Rehm. ex Salm., a South African moss with a thickened border. The type specimen (SOUTH AFRICA. Natal: Inanda, Rehmann 289, bm) was compared but found to have a diflferent costal structure and, as reported by Salmon (1899) and others, the laminal cells have a hyaline dot and the margins are mostly bistratose, features not found in either F. sufflatus or F. pseudopallidus.

Fissidens holstii Broth, which is closely allied to F. nitens is often found associated with F. sufflatus and F. pseudopallidus. It is a common moss in Queensland and has been known under the name F. kurandae Broth, et Watts but examination of the types of both the African F. holstii (Hoist 9195, h) and F. kurandae (W. W. Watts 273, h) showed the two to be conspecific; therefore, F. kurandae must be reduced to the synonymy of F. holstii.