Specimen #3: Leucobryum glaucum

Collection #: 3

Scientific Name: Leucobryum glaucum

Phylum: Bryophyta; Bryopsida

Order: Dicranales

Family: Leucobryaceae

Common Name: pincushion moss

Location: Camp Asbury, Hiram

Habitat: In the middle of a wet muddy trail

Date of collecting: August 30th

Collector: Cornelia

Notes: like a fluffy little animal

How did I key this out:

Fig.1 Group picture                                                                              Fig.2 Single plant

As you can see in the picture (Fig.2), it is pretty clearly that this plant is in the acrocarp growth form just like it's close relative Leucobryum albidum for my specimen #2, and the group of the plant also looks pretty alike except for the size of it (Fig.1). The leaf picture (Fig.3) shows that this specimen is with lance-shaped leaves without a midrib. By knowing these features, we could now go to the key: KEY II: Acrocarps with Lance-shaped Leaves.

Fig.3 Picture of a single leaf


The following steps is how I went through the keys:
1. (A) Plants gray or whitish green (dry) to light green (wet) (see fig.1 for this fact.); shoots very densely packed together forming domed mounds (see fig.2 for this fact.); leaves tubular in upper half and seemingly without midrib. (See fig.3 and fig.4 for this fact.) (2)
2. (A) Stems 1-9 cm tall; leaves 4-8 mm long; rarely with capsules. (Leucobryum glaucum, P123)

 Fig.4 Cell structure

Description of the species:
Appearance: Upright plants form dense, usually round cushions on the ground, like white-green sea urchins, brighter green when wet. Densely packed stems are 1-9 cm high, covered in leaves that are held stiffly straight or very slightly curved away from stem. When teased apart, upper stems are opaque pale green and previous growth below is dead-looking brown. 
Leaves: Lance shape, 4-8 mm long, with a flat, dear, egg-shaped base (with air bubbles inside visible v 1 a hand lens) from which extends an opaque blade with in-rolled edges, forming a trough or tubular stocky needle shape. Midrib is lacking, edges are smooth. 
Capsules: Cylindrical, 2 mm long, curved over, with a small bump at base and a long-beaked lid. Stalk is rust-colored, 9-17 mm tall. Capsules are infrequently produced; the plants reproduce vegetatively from bits of branches or leaves that break off. 
Habitat: Forest soil, often over mounds in the ground that are the remains of nearly decomposed logs, or growing on more recently fallen logs. 
Microscopic Features: Thick fleshy leaves are composed mainly of midrib, which consists of green, cholorphyll-containing cells sandwiched between layers of large, colorless cells (Fig.4). Actual leaf blade is reduced to a narrow band of dear cells on either side of midrib. 

Collecting and keying story:

August 30th was before the class actually started. It was an pre-class field trip about mushrooms when I collected this sample. I could still remember how cute the plant was, the group was a really small one and it just lays in the middle of the muddy trail. I picked it up and couldn't help myself but fondled it before I put it into the plastic bag. It was just so cute.


Phylum, order and family name cited from:
http://plants.usda.gov/core/profile?symbol=LEGL19

Keys cited from:

  Common Mosses of the Northeast and Appalachians by Karl B. McKnight, Joseph R. Rohrer, Kirsten McKnight Ward and Warren J. Perdrizet. This book is in the series of the Princeton Field Guides and was published by Princeton University Press with copyright @ 2013.