Bryoerythrophyllum P.C.Chen

The following generic description is modified from Zander (1993).

Plants usually green above and often brick-red below, forming turves or tufts on soil or rock. Stems occasionally branched, in cross-section central strand present, sclerodermis usually present (weak in N.Z. species), hyalodermis usually absent. Leaves erect-spreading to spreading when moist, ± erect-twisted when dry, ovate to lanceolate or lingulate, rounded-obtuse to acute (in N.Z. species); margins recurved or plane, entire or crenulate-papillose and often dentate above; upper laminal cells obscure, subquadrate (in N.Z. species) to short-rectangular, pluripapillose with complex papillae; upper marginal cells not differentiated or ± oblate in 1–2 rows; lower laminal cells usually thin-walled, hyaline and rectangular. Costa failing a few cells before apex to short-excurrent, in cross-section with 2 stereid bands. Laminal KOH colour reaction orange-red to red.

Dioicous or occasionally monoicous. Perichaetia terminal, with leaves usually larger than vegetative leaves and sheathing in their lower half. Perigonia terminal, bulbiform. Setae elongate. Capsules ellipsoid to cylindric, sometimes arcuate; annulus well developed. Operculum short-conic to short-rostrate. Peristome well developed (in N.Z. species), rudimentary or none. Spores 8–18 µm, smooth or papillose.

An essentially cosmopolitan genus of some 27 species, only two of which are found in N.Z.

N.Z. species of Bryoerythrophyllum may be recognised by a suite of leaf characters: lower leaves often brick-red, upper laminal cells densely pluripapillose and sometimes with a conspicuous single-celled hyaline apiculus terminating the acute leaf apex, a prominent area of lax, hyaline, thin-walled cells in the lower lamina, and an orange-red to red laminal KOH reaction. In addition, a few teeth are sometimes present on the upper laminal margin.

Bryoerythrophyllum species have been confused with members of several other genera. Hyophila leaves may have a brick-red coloration, but broadly acute to obtuse leaf apices that lack a hyaline apiculus. Trichostomopsis australasiae is superficially similar to both N.Z. species of Bryoerythrophyllum, and also has hyaline, thin-walled lower laminal cells. However, the leaf margins in T. australasiae are bistratose above and the leaf apex is usually narrowly obtuse, and lacking both a hyaline apiculus and teeth. In addition, the brick-red colour of Bryoerythrophyllum does not occur in T. australasiae. Both Streblotrichum convolutum and Syntrichia phaea may have a similar hyaline leaf apiculus. S. convolutum can be distinguished by its lower laminal cells being little differentiated from those above (vs strongly differentiated lax, hyaline, thin-walled lower laminal cells in Bryoerythrophyllum) and a yellow laminal KOH reaction (vs orange-red to red in Bryoerythrophyllum). Syntrichia phaea differs in colour, being very dark green or even black (vs mid-green above, often brick-red below in species of Bryoerythrophyllum).

Bryoerythrophyllum alpigenum (Vent.) P.C.Chen.

Records for N.Z. (Gangulee 1969–1972, p. 741; Zander 1993, p. 292) are presumed to stem from the acceptance by Dixon (1923, p. 125) of Didymodon rubellus var. dentatus Schimp. as a N.Z. moss, and the subsequent synonymy of that taxon with B. alpigenum, proposed by Chen (1941). The type of B. alpigenum has not been seen for this study, but comparison of descriptions and illustrations for the taxon provided by Chen (1941, p. 258) indicate that leaf margin recurvature is more extensive in N.Z. material (confined to the middle ⅓ or ½ of the leaf length in Chen’s illustrations of B. alpigenum) and toothing much less (conspicuous teeth present on the distal ½ of the leaves in B. alpigenum). B. alpigenum is thus not accepted for the N.Z. flora.