1. Dichelyma capillaceum (Dicks.) Myr. (Bryopsida:Fontinalaceae)

Abstract

Dioicous, male and female plants similar (Fig. 1). Plants medium-sized, irregularly pinnately or irregularly and sometimes sparsely branched, green or brownish green, not or very weakly glossy when dry. Stem leaves inserted in three distinct or sometimes indistinct rows, when moist slightly to moderately strongly falcato-secund, when dry slightly twisted, otherwise little changed, lanceolate, somewhat keeled (± V-shaped in transverse section), gradually narrowed to very long, ,narrowly acuminate apex, 3.26-6.12 mm long and 0.26-0.63 mm wide, upper 26-46% of leaf consisting entirely of the excurrent nerve, neither plicate nor transversely undulate; nerve single, longexcurrent, 42.0-77.5 Jlm wide near insertion, in transverse section plano-convex, 4-6stratose, cells ± homogeneous, surface cells on both adaxial and abaxial sides linear, similar to adjoining lamina cells, lateral sides of nerve near apex denticulate or usually coarsely denticulate or dentate; margin of lamina and lower part of excurrent nerve very weakly and obtusely denticulate to ± entire, plane, marginal 1-3(-4) cell rows of leaf lamina frequently bistratose, but otherwise not differentiated from other lamina cells; median lamina cells 48.3-252.0 x 5.0-8.8 Jlm, linear and slightly flexuose, with tapering or longly tapering ends, thin-walled or slightly incrassate, eporose, smooth; basal lamina cells shorter and slightly wider than mid-leaf cells, slightly to strongly incrassate, eporose or slightly porose; alar cells not different from other basal cells; in the ontogeny of the leaf lamina the basal cells are the last leaf cells to differentiate, and all basal cells differentiate ± simultaneously; shortly and narrowly decurrent; apical lamina cells linear, but usually somewhat shorter than mid-leaf cells, slightly incrassate, eporose. Branch leaves similar to stem leaves but slightly smaller, proximal branch leaves ovate and acute or shortly acuminate. Protonema often found on old leaves, especially on the nerve or sometimes on leaf margin, more rarely on other leaf portions, consisting of uniseriate, mostly unbranched threads of rectangular or shortly rectangular and slightly incrassate cells. Pseudoparaphyllia foliose, broadly ovate or broader than wide, with obtuse or rounded apex. Paraphyllia absent. Rhizoids inserted below leaf insertions, often on the branches, red-brown, not or hardly branched, smooth. Axillary hairs 2-3 in each axil, strictly axillary, with 2-4 upper cells, 7.8-10.5 Jlm wide, hyaline, and basal cells 1-2, rectangular to shortly linear, pale brown. Stem without central strand, cortex (including epidermis) of 3-4 layers of small and incrassate cells, basic tissue of large, thin-walled o~ slightly incrassate cells, no hyalodermis, flattened or slightly flattened. Perigonia lateral on stems and branches, perigonial leaves ovate, suddenly narrowed to obtuse,