Common Name: Nitrogen Moss

Habitat: Found on old dung of carnivores (fox, wolf, and dog); locally on owl pellets among Sphagnum under a tree in an open peatland. In North Wales, Tetraplodon is most abundant beneath dangerous mountain crags where there is a steady supply of sheep carcasses. Under ideal conditions, these mosses are so successful that in central Alberta, uncolonized droppings are rare.

Distribution: Northern and central Europe; Japan; Greenland and Newfoundland across the continent to Alaska, south to British Columbia, the Great Lakes.

Gametophyte: Perennial, found in dense cushions, matted, with rhizoids below. Stems often bear club hairs in upper leaf axils. Leaves somewhat larger at stem tips, concave, oblong lanceolate to ovate, gradually or abruptly slenderly long-tapered. Leaf margins erect, entire or toothed above. Costa usually vanishing in the subula. Cells short-rectangular to oblong hexagonal and firm above, laxer and oblong below.

Sporophyte: The seta is short to elongate, stout. Capsules are differentiated into a small, short-cylindric urn, not shrinking after dehiscence, and a narrowly pear-shaped hypophysis usually somewhat broader and longer than the urn and the same color or darker. Columella not or rarely somewhat exerted. Annulus mostly absent. Operculum hemispheric to bluntly conic. Peristome teeth deeply inserted, joined in groups of four, reflexed when dry, inflexed when moist. Calyptra small, conic and undivided, eventually split on one side, not constricted above the base, smooth and naked.

Species: 18 species, subspecies and varieties.** T. mnioides (entire-leaf nitrogen moss), T. pennsylvanicum, T. paradoxus (paradox nitrogen moss), T.pallidus (pale nitrogen moss), T. angustatus (toothed-leaf nitrogen moss), T. urceolatus (urceolate nitrogen moss), T. tomentosus, T. itatiaiae, T. caulescens, T. blyttii, T. ampustatum, T. bryoides, T. crosseanus, T. fuegianus, T. lamii, T. pectinatum, T. stenophysatus

More Information:
Family: Splacnaceae
Genus name refers to peristome teeth arranged in groups of four.
The spores are dispersed by flies. The spore capsules give off a scent of rotting animal which is attractive to flies. They pick up the spores and deposit them on the next rotting animal they visit.*

References:
Crum, Howard, Mosses of the Great Lakes Forest, 4th ed., University of Michigan: Ann Arbor.
Shaw, A. Jonathan, Bryophyte Biology, Cambridge University Press.
* www.p2007/08/tetraplodon-mnioides.html
**zipcodezoo.com/Plants/T/Tetraplodon_paradoxus.asp

Written by Patricia Contreras 2008