BFNA Title: Echinophyllum
HELODIACEAE – ECHINOPHYLLUM
XXX. ECHINOPHYLLUM T. J. O’Brien, Bryologist 103: 513. 2000 • [Greek echinos, sea-urchin or hedgehog, and phyllon, leaf]
Terry J. O’Brien
Plants small to medium sized, in mats, green or yellowish green. Stems prostrate, 1-pinnate or less commonly irregularly 2-pinnate; paraphyllia polymorphous, commonly branched-filiform, less commonly unbranched or narrowly lanceolate, distal cells oblong, smooth or papillae present over end walls, terminal cell lanceolate, smooth, crowned with a bluntly conic cell wall thickening; pseudoparaphyllia lanceolate (or ovate-lanceolate), with ciliate or serrate margins, proximal cells subquadrate and commonly centrally papillose. Stem leaves distant, spreading, deeply 2--4-plicate, broadly ovate, rarely elliptical, abruptly narrowed to a subulate, flexuose or circinate acumen; proximal margins plane or recurved, fimbriate with paraphyllia-like appendages; distal margins spinose-serrate; acumen margins smooth or distantly serrulate; laminal cells with a single bluntly conic papilla on abaxial surface and smooth or papillose on adaxial surface; cells of the acumen smooth, oblong or linear. Branch leaves slightly overlapping, spreading or spreading-erect, ± catenulate when dry, differentiated from stem leaves, broadly ovate and concave, abruptly narrowed to an acute tip; distal medial cells irregular and rhombic, oblong or subquadrate, walls incrassate, terminal cell lanceolate, smooth, with a distal bluntly conic wall thickening. Sexual condition dioicous.
Species 1: nw North America, Asia (e China; Japan; Korea; e Russia).
SELECTED REFERENCES: O’Brien, T. J. and D. Horton. 2000. Bryochenea (Musci; Thuidiaceae) is Cyrto-hypnum (Thuidiaceae), but B. sachalinensis is Echinophyllum (Thuidiaceae), a new genus from the Pacific Rim. Bryologist 103: 509--517. O’Brien, T. J. 1993. Bryochenea sachalinensis (Thuidiaceae) new to North America in south-central Alaska. Bryologist 96: 205--209.
1. Echinophyllum sachalinense (Lindberg) T. J. O’Brien, Bryologist 103: 513. 2000
Thuidium sachalinensis Lindberg, Contributio ad Floram Cryptogamam Asiae Boreali-Orientalis 244. 1872; Bryochenea sachalinensis (Lindberg) C. H. Gao & K. C. Chang; Helodium sachalinense (Lindberg) Brotherus
Stems with branches spirally attached; paraphyllia abundant on stems and branches; axillary hairs with a brown, short basal cell and 2--4 hyaline, oblong distal cells. Stem leaves with costa single, ending at base of or before acumen, adaxial surface with paraphyllia attached along base, smooth or irregularly serrate distally; proximal cells irregular, oblong or subquadrate with incrassate walls, sporadically porose walls; cells at midleaf irregular and incrassate, rhombic, oblong or subquadrate. Branch leaves with margins plane or recurved proximally, plane and serrate or serrulate distally; costa single, about 1/2--2/3 the leaf length. Specialized asexual reproduction absent. Perichaetia lateral; perichaetial leaves differentiated from stem leaves, outermost with an oblong base rather abruptly narrowed to a finely acuminate, flexuose tip, plicate; costa ending in acumen, margins entire proximally and serrate at base of acumen; distal cells linear or oblong-linear, smooth, walls thin or incrassate and sporadically porose. Seta 2--3 cm, twisted when dry, smooth. Capsule inclined, curved and asymmetric or straight, cylindric; annulus revoluble; operculum convex-conic, rostellate or rostrate; peristome hypnoid; exostome teeth 16, lanceolate, yellowish, connate and cross-striolate proximally, papillose distally; endostome hyaline, basal membrane high, distal segments alternating with 3--4 long, appendiculate cilia. Calyptra not observed. Spores globose or subglobose, 10--16 µm, minutely papillose.
Usually on humus over soil or rock, also bark of conifers and hardwoods, rotting logs, moist coniferous forest or mesic tundra; B.C.; Alaska.
Echinophyllum sachalinensis is best distinguished from similar species by the combination of stem leaves with slender, recurved tips; coarsely serrate-dentate leaf margins often with cilia attached proximally; one massive papilla per leaf cell; branch leaves with a smooth, lanceolate terminal cell; paraphyllia with smooth, lanceolate terminal cells; and lanceolate, papillose pseudoparaphyllia. This species is known from five localities in North America along the northern Pacific Rim, all discovered since 1992. Specimens from four of the localities are reported by T. J. O’Brien and D. Horton (2000); a fifth locality is near Mother Goose Lake in Alaska (W. B. Schofield, personal communication).