|A spreading colony of Rhynchostegium serrulatum. All
photos by Robert A.Klips, Ohio Moss and Lichen Association.
|Leaves are notably toothed and the midrib peters out before
the tip. Cells are long and worm-like.
|Spore capsules are strongly arched, with
a swollen tip.
From it's bent spore capsules and spreading leafy stems, this species could be mistaken for the common Isopterygium tenerum. Even the elongate, worm-shaped leaf cells are similar. But the most obvious difference is the presence of a midrib here, which is lacking in Isopterygium and the greater number of teeth along the leaf margin. The capsules of Rhynchostegium are also more slender and more bent, almost into a U-shape, but with the tip enlarged and more cone-shaped. Differences between the Brachystegiaceae and the Hypnaceae, to which Isopterygium belongs, are obscure and technical.