BFNA Title: Anastrepta
XX. ANASTREPTA (Lindberg) Schiffner, Hepat. in A. Engler & G. Prantl, Nat. Pflanzenfam. 1(3): 85. 1893 * [Greek ana-, throughout, and strept-, turn, alluding to leaf tips facing the same direction]
Jungermannia sect. Anastrepta Lindberg in Lindberg & Arnell, Kongl. Svenska Vetensk.. Handl., n.s. 23(5): 40. 1889
Dale H. Vitt
Plants ca 2--8(--12) cm long, 0.6--3.5 mm wide, reclining to erect. Stem transverse section with 3--4 cortical cells and 15--25 medullary cells; rhizoids short, colorless to pale brown. Leaves subtransversely-obliquely inserted, often strongly asymmetric, weakly and usually unequally 2-lobed, sinus obsolete or to 1/6 leaf length or less, often unlobed, asymmetric; cells with thin or somewhat thickened walls, trigones small to large and convex; oil bodies 3--16 per cell, homogeneous or faintly granular; underleaves absent. Sexual condition dioicous. Specialized asexual reproduction by gemmae. Androecia apical becoming intercalary with age, antheridial stalk 2-seriate, female bracts leaf-like, undulate and somewhat crispate, 2--5-lobed, bracteoles 1--2-lobed. Perianth ellipsoidal to obovoid, suddenly narrowed to a dentate-ciliate mouth. Sporophytes unknown in flora area.
Species 1 (1 in the flora): widely scattered in oceanic and mountainous areas, nw N. Amer. Europe, Asia, Pacific Ocean Islands (Hawaii).
SELECTED REFERENCES: Paton, J. A. 1999. The Liverwort Flora of the British Isles. Harley Books, Essex, England.
1. Anastrepta orcadensis (Hooker) Schiffner, Hepat. in A. Engler & G. Prantl, Nat. Pflanzenfam. 1(3): 85. 1893
Jungermannia orcadensis Hooker, Brit. Jungermann, pl. 71. 1815
Plants loose, slender, unbranched, growing among other bryophytes, dull green to olive-green to reddish brown. Leaves shallowly notched, erect to squarrose and reflexed toward to the ventral side of the shoot, about 1.8 mm long and wide, concave at base, otherwise plane or antically recurved, leaf cells 18--23 /um wide.
Among other bryophytes on peaty banks and humus on and around cliffs; sea level to subalpine; B.C.; Alaska; Europe; Asia (China, Japan, Russia).
The very shallowly bilobed, convex leaves are characteristic of Anastrepta orcadensis. Additionally, the postical portion of the leaves is strongly recurved, and there are no underleaves.