BFNA Title: Hypopterygiaceae
Author: R. H. Zander
Date: October 6, 2010
Edit Level: R
Version: 1

Bryophyte Flora of North America, Provisional Publication
Missouri Botanical Garden

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Richard H. Zander

Plants medium-sized to large, mat-forming, primary stem stoloniform, creeping, secondary stems often dendroid, often much-branching. Stems brownish green, hyalodermis and sclerodemis not differentiated, central strand commonly strong. Branches complanate-foliate, dorsiventral. Leaves dimorphic, the dorsal or lateral larger, in two rows, somewhat asymmetric, the ventral smaller, symmetric; leaves ovate, oblong or lingulate, commonly bordered with differentiated cells; margins serrulate or entire, occasionally dentate or ciliate; costa single, sub-percurrent; laminal cells rounded-rhombic to hexagonal, papillae absent [lumens 1-papillose]. Sexual condition dioicous, sometimes autoicous or heteroicous. Seta elongate [short], straight or curved, smooth. Capsule cylindric [subglobose, ovoid], usually inclined; operculum rostrate; peristome teeth 16, double [exostome occasionally absent], exostome usually cross-striolate, medially furrowed or with a zigzag line, trabeculae well developed; cilia well developed or absent. Calyptra cucullate or conic-cucullate [mitrate].


Genera 4(--8), species 9(--26) (1 genus, 1 species in the flora): worldwide in tropical and warm temperate regions, apparently introduced in Europe.


SELECTED REFERENCES  Kruijer, J. D. 2002. Hypopterygiaceae of the World. Blumea Suppl. 13: 1--388. Lawton, E. 1971. Moss Flora of the Pacific Northwest. Nichinan. (Moss Fl. Pacif. N.W.)


1. HYPOPTERYGIUM Bridel, Bryol. Univ. 2: 709. 1827 * [Greek hypos, below, and pterygium, small wing, alluding to underleaves]


Plants pale green, pinnate, flabellate, palmate, or umbellate; terminal cell of axillary hairs of equal throughout plant. Stem branched, lacking rudimentary branches; stipe cavities absent. Specialized asexual reproduction absent. Leaves with acute or acuminate apices; margins entire to dentate, never ciliate, bordered by 1--2 rows of long-rhomboidal cells; costa of lateral frond leaves ending before the apex; laminal cells rhomboidal, prosenchymatous, walls thin or weakly incrassate. Sexual condition autoicous. Seta elongate, smooth. Capsule horizontal.


Species 19(--55) (2 in the flora): North America, Central America, South America, Europe, Asia, Africa, Pacific Islands (including New Zealand), Indian Ocean Islands, Australia.


1. Dorsal frond leaves present on basal portion of stipe, stipe and basal frond leaves in 8 rows; paraphyses absent . . . 1. Hypopterygium flavolimbatum


1. Dorsal frond leaves lacking on stipe, stipe and basal frond leaves in three or eleven or more rows; paraphyses present . . . 2. Hypopterygium tamarisci



1. Hypopterygium flavolimbatum Müller Hal., Syn. Musc. Frond. 2: 10. 1850


Hypopterygium canadense Kindberg; H. fauriei Bescherelle


Plants 1--2.5(--3) cm. Leaves of stipe and basal fronds in eight rows, to 0.9 mm; dorsal frond leaves present on basal portion of stipe; distal stipe leaves 1.2--1.7(--2) mm, often asymmetric, entire to evenly serrate in distal 1/4--1/2; ovate to very short-acuminate; costa short or reaching to 4/5\x leaf length. Perichaetia lacking paraphyses. Seta 1--1.5(--2.5) cm, smooth or weakly papillose distally. Capsule 1--1.5 mm; operculum rostrate, 1.2--1.5 mm.


Limy humus, limestone, outcrops, cliffs, small cavern, moist, shady forests, Pacific coastal islands; 0--100 m; B.C.; Alaska; Asia.


Hypopterygium flavolimbatum is a small but striking moss, with erect, bright green fronds of neatly arranged dimorphic leaves.


2. Hypopterygium tamarisci (Swartz) Bridel ex Müller Hall., Syn. Musc. Frond. 2: 8. 1850


Hypnum tamarisci Swartz, Fl. Ind. Occid. 3: 1825. 1806


Limestone sink; 0 m; Fld.; Mexico; West Indies; Central America; South America, c Africa, se Asia; Indian Ocean Islands; Pacific Ocean Islands.


Plants 2.5--4 cm. Leaves of stipe and basal fronds in 3 or 11 or more rows, 1--1.5 mm; dorsal frond leaves absent from stipe; distal stipe leaves 0.8--1 mm, asymmetric, serrate in distal 1/2; ovate; costa short or reaching 1/2--2/3\x leaf length. Perichaetia with paraphyses. Seta ca. 1.5 cm, smooth. Capsule ca. 1 mm; operculum long-rostrate, ca. 1.5 mm.


Hypopterygium tamarisci, of pan-tropical distribution, was reported once from Alachua County, Florida (M. W. Diddel and E. M. Shields 1943), in a lime sink about 7 km southeast of Newberry (NY!). It differs from H. flavolimbatum in lacking dorsal frond leaves on basal stipe, stipe and basal frond leaves in three or eleven or more rows, and paraphyses present. This taxon has apparently been extirpated from the flora region, according to J. D. Kruijer (2002). The next closest station is in Cuba. The relationships of this species were investigated by H. Kruijer and R. Blöcher (2007) and T. Pfeiffer (2000).


SELECTED REFERENCES Diddel, M. W. and E. M. Shields. 1943. A moss new to Florida. Bryologist 46: 22--23. Kruijer, H. and R. Blöcher. 2007. Reevaluation of the phylogeny of the Hypopterygiaceae (Bryophyta) based on morphological and molecular data. In: A. E. Newton and R. S. Tangney. 2007. Pleurocarpous Mosses: Systematics and Evolution. Systematics Association Special Volumes 71: 65--109. Pfeiffer, T. 2000. Systematics of the Hypopterygium tamarisci complex  Hypopterygiaceae, Bryopsida): Implications of molecular and morphological data. J. Hattori Bot. Lab. 89: 55--70.