Parasite Syrrhopodon Moss

In dry plants of Syrrhopodon parasiticus, the abaxial surface of the costa is often very conspicuous, an aid to identification in the field. In the northern portion of its range plants are mostly small and inconspicuous, but in southern Florida the plants are often robust, tufted, and conspicuous. Plants with sporophytes are restricted to south of Highlands County, Florida. Robust plants in southern Florida often have teniola-like intramarginal fetures in the proximal parts of the leaves.

Syrrhopodon parasiticus is easy to recognize by its characteristic habit and habitat, and by its pointed leaves with narrow acute cancellinae and filamentous gemmae adaxially along the costa at midleaf. Although the extent of the hyaline border and the abaxial ornamentation of the leaf cells are variable, this is a well-defined species. Even though the plants are rarely or never conspicuous in the field, they can usually be found by careful searching in appropriate habitats. Twigs and branches of trees in humid sites are especially characteristic habitats for S. parasiticus.

Plants solitary, gregarious, or tufted, dark green to brownish, to 2 cm but mostly much shorter. Leaves dimorphic; vegetative 2-4 mm, loosely contorted when dry; distal lamina somewhat reflexed above shoulders, often somewhat folded when wet, oblong to broadly lanceolate, apex acute; margins mostly bordered entirely or in part with hyaline cells at least on some leaves, entire; medial cells distinct, 8-10 µm, bulging adaxially, smooth to 1-papillose abaxially; cancellinae ending in acute angles distally; gemmiferous leaves often aggregated into splash-cup comae at stem tips, tightly appressed when dry, spreading-ascending when wet, oblong-deltoid, acute. Gemmae filamentous, smooth, abundant, adaxial along costa of distal lamina. Seta single or 2-3 per perichaetium, 2-3 mm. Capsule emergent to exserted, 1-1.5 mm; peristome vestigial.

Plants small, ca. 1 cm high, green to blackish, solitary, loosely gregarious, or in tufts of a few plants. Stems short, rhizoids reddish brown, scanty. Leaves often dimorphic, involute and falcate when dry, mostly folded and spreading when wet, curved, vegetative leaves narrowly lance-acuminate, grading into the deltoid and often comose gemmiferous leaves, mostly 3–4 mm long, axillary hairs inconspicuous; cells of upper laminae pellucid, isodiametric to short-rectangular, smooth to sharply unipapillose abaxially, bulging adaxially; margins of upper laminae narrowly bordered entirely or in part with hyaline cells, border sometimes more or less lacking or only in traces here and there, entire or irregularly with small, remote denticulation, margins of lower laminae entire, with or without border of hyaline cells; cancellinae ending in narrow acute angles distally. Gemmae common, filamentous, borne adaxially along costa at midleaf, gemmiferous leaves narrow, similar to vegetative leaves or short, broad, deltoid, and forming comae at stem tips. Sporophytes not seen.

Distribution: pantropical.

Habitat: evidently infrequent but easily overlooked; solitary, tufted, or in small thin colonies on tree trunks, twigs, and branches, often along streams, often high up in trees, in more or less open forests at medium elevations.

Bryum parasiticum Bridel, Muscol. Recent. 2(3): 54. 1803; Calymperes filigera Austin; Calymperopsis parasitica (Bridel) Brotherus; Syrrhopodon filigerus (Austin) R. S. Williams

Calymperopsis involuta P.-J. Lin, Acta Phytotax. Sin. 17(1): 92. 1979. Type. China: Hainan, P. C. Chen et al. 518c (holotype IBSC). Paratypes. China: Hainan, P. C. Chen et al. 497b (IBSC); Yunnan, Xi-shuang-ban-na, W.-X. Xu 6166 (YUKU).