Thursday, July 20, 2017

Mosses of Central Florida 24. Anomodon minor

Anomodon minor has creeping  primary stems with short, scale-like leaves
and semi-erect branches with larger, tongue-shaped leaves. Photo from dried
herbarium specimen: Merner s.n. 15 June 1979 (USF)
Anomodon minor (Hedwig) Lindberg (Anomodontaceae) is a creeping moss occurring on bark at the bases of trees.  It is distributed widely in North America, extending south to Hillsborough and Polk Counties in central Florida. It has
Capsules of Anomodon minor are erect (unbent) and symmetrical.
Photo courtesy Robert A. Klips, Ohio Moss and Lichen Association.
two orders of leafy stems.  The primary stems creep horizontally along the substrate, and bear relatively short, scale-like leaves, while branch stems are semi-erect to spreading, with larger, tongue-shaped leaves. Branch leaves are broadly rounded at the tip with a short, hard point, have a distinct midrib, and the cells are small, roundish, and papillate (with hard, translucent bumps). When dry, the leaves fold against the stem. Capsules are erect and essentially symmetrical.  In habit and leaves, it somewhat resembles members of the Thuidiaceae, into which this genus is sometimes placed, but in that family, primary stem leaves are larger than the scale-like branch leaves, in both types of stems there are leaf-like paraphyllia between the true leaves, and capsules are asymmetric and bent to the side.


Within the Anomodontaceae, Anomodon is distinguished from the only other genus, Herpetineuron, by the shape and other features of the leaves. In Herpetineuron, leaves gradually taper to a point and the cells are smooth, without papillae.  Three other species of Anomodon occur in Florida.  A. tristis appears to form thinner mats, occurs higher up on tree trunks, and is found only in the northern part of the state. A. attenuatus forms denser mats, with more frequently branched stems that lay more-or-less flat, and taper at the ends with increasingly smaller leaves.  In A. rostratus, leaves are long and taper to a fine, hair-like point.
Leaves of Anomodon minor are elongate, tongue-shaped and with a rounded
tip with small hard point. Cells are tiny, roundish and equipped with papillae.
Lighter streak in the center is the midrib. 

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