BFNA Title: Myuroclada
Author: W. B. Schofield 
Date: November 15, 2007
Edit Level: R
Version: 1

Bryophyte Flora of North America, Provisional Publication
Missouri Botanical Garden

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Myuroclada - Brachytheciaceae



XX. MYUROCLADA Bescherelle, Ann. Sci. Nat. Bot. Ser. 7, 17: 379. 1893 * [the leafy stems have appearance of mousetails]

W. B. Schofield


Plants pale silvery green, glossy, creeping, irregularly branched; leafy branches often erect arcuate, strongly julaceous, sometimes attenuate to flagelliform, 1--5 cm, 0.5--1.5 mm wide; rhizoids confined mainly to creeping stem.  Pseudoparaphyllia orbicular-triangular. Leaves of stem and branches similar, crowded, imbricate, orbicular to broadly ovate, 0.5--2 mm, short-apiculate when young, blunt when mature; margins somewhat recurved near base, nearly entire; costa simple, ending at mid-leaf or slightly beyond; leaf cells smooth, short-rhombic to rhombic, 35--45 x 5--7 /um, alar cells smaller, not sharply differentiated.  Specialized asexual reproduction lacking.  Sexual condition dioicous.  [Seta smooth, red-brown, 15--30 mm.  Capsule inclined to horizontal, weakly curved, nearly black when old, oblong, 1.5--2.5 x 0.9 x 1.2 mm; annulus shed in fragments; operculum high-conic with oblique beak, 1--1.5 mm; peristome double, exostome teeth linear-lanceolate, often filiform, papillose distally, striolate and orange-brown proximally, endostome equal to exostome in length, segments filiform distally, perforated, cilia 2.  Calyptra smooth, cucullate.  Spores spherical, scabrous, 12--16 /um.]


Species 1 (1 in the flora): Alaska; e. Asia (Japan, Korea, Russia); introduced to Europe; a forest species, rock, logs, up tree bases and on tree trunks, terrestrial, also on walls in urban habitats.


SELECTED REFERENCES   Ignatov, M. S. and S. Huttunen. 2002. Brachytheciaceae (Bryophyta)---A family of sibling genera. (7. Myuroclada). Arctoa 11: 264--265.  Noguchi, A. 1991. Illustrated Moss Flora of Japan, Part 4: 938--941. Nichinan.  Steere W. C. and W. B. Schofield. 1956. Myuroclada, a genus new to North America.  Bryologist 59: 1--5.



1. Myuroclada maximowiczii (G. G. Borshchow) Steere & Schofield, Bryologist 59:1. 1956


Hypnum maximowiczii G. G. Borshchow in C. J. Maximowicz, Primit. Florae Amurensis. 467. 1859; Myuroclada concinna (Wilson) Bescherelle, Ann. Sci. Nat. Bot. VII, Ser 17: 379. 1893


Plants medium-sized, unbranched to weakly branched, sometimes without reclining stems, to 2 cm. Stems 0.5 mm wide or less.   


Sporophytes are lacking in North America. Mainly flood zones along rivers, usually terrestrial on silt, but also on tree bases; Alaska, e Asia, introduced to Europe.


Myuroclada maximowiczii is rare in the range of the flora. It resembles an overgrown Myurella julacea, but the smooth leaf cells and clearly costate leaves readily separate it.