Eulacophyllum

• Authority

  Ireland, Robert R. & Buck, William R. 1994. Stereophyllaceae. Fl. Neotrop. Monogr. 65: 1-49. (Published by NYBG Press)

• Family

  Stereophyllaceae

• Scientific Name

  Eulacophyllum

• Type

  Type. Hypnum cultelliforme Sullivant = Eulacophyllum cultelliforme (Sullivant) Buck & Ireland

• Description

  Genus Description - Plants small-sized, somewhat complanate, in thin, light-green to yellowish green, glossy mats. Stems creeping, simple or sparingly and irregularly branched; cortical cells small, thick-walled, central strand lacking; rhizoids smooth, in clusters below leaf insertions on ventral surface of stems; pseudoparaphyllia filamentous; axillary hairs with a single brown basal cell and two hyaline apical cells. Asexual propagula unknown. Stem and branch leaves similar, stiff, mostly distant, erect-spreading, complanate or slightly concave, scarcely altered when dry, smooth, often asymmetric, non-decurrent, oblong-lanceolate to oblong-ovate, sometimes lingulate, cultriform, acute to obtuse; margins plane, serrate to serrulate in upper half, serrulate to entire below; costa single, apical end of terminal cell projecting on dorsal surface as a small spine; cells firm-walled, upper cells long-rectangular to long-hexagonal with thickened, blunt ends, often appearing prorulose but smooth or nearly so, 10-15:1, becoming shorter near the leaf apex, not porose; alar regions usually distinctly differentiated, cells quadrate to rectangular, small, often many on one side of costa and few on other, sometimes few on both, collenchy-matous, usually extending over adaxial surface of costa. Autoicous, rarely producing sporophytes; perigonia scattered along stems, bracts lanceolate-ovate, short-acuminate, ecostate; perichaetia along stems, especially at the bases, leaves ovate-lanceolate, erosely shouldered, costate. Setae smooth, elongate, straight to somewhat flexuose, orange to red-brown; capsules cernuous, slightly asymmetric, orange, smooth, ellipsoidal to ovoid; exothecial cells thick-walled; annulus of 2-4 rows of small, thin-walled cells; opercula short-rostrate, sometimes oblique; peristome double, exostome teeth bordered, shouldered, outer surface cross-striolate below, papillose above, inner surface projecting; endostome smooth to finely papillose, basal membrane high, segments keeled, perforate, almost as long as the teeth, cilia often single, slightly shorter than the segments. Spores spherical, papillose, 9-13 |im in diam. Calyptrae cucullate, smooth, naked.

• Discussion

  This is a monotypic genus recently segregated from Entodontopsis by Buck and Ireland (1985). It differs from that genus by its areolation, the leaf cells are blunt with thickened ends giving the impression of prorulosity, by the thick-walled exothecial cells, and by the thin-walled annular cells. Eulacophyllum is further distinguished by the small, somewhat complanate plants, stems to 2 cm long, by the leaves scarcely altered when dry, with mostly obtuse apices, margins densely serrate in the upper half, and by the small, very unequally distributed quadrate to rectangular alar cells.

• Distribution

  Eulacophyllum occurs most often on sandstone or limestone, in semi-dry tropical regions of the New World.