Entosthodon subnudus (Taylor) Fife

Plants yellow- or brown-green. Stems red-brown, 2–5 mm, branching once by subperigonial innovation, beset with red-brown rhizoids. Leaves erect-spreading, obovate to oblong-obovate, occasionally widest below mid leaf and ± oblong-ovate, tapered in upper ⅓ to a broadly acute, acuminate, cuspidate, aristate, or rarely obtuse apex, (1.3–)1.5–2.5 × 0.6–0.8 mm, variably concave, entire or rarely bluntly dentate in upper ½; upper laminal cells oblong-hexagonal, (24–)30–69(–80) × 15–18(–25) µm, becoming larger, more oblong, and laxer below; marginal cells not differentiated; apical cell length variable, (45–)60–165 (rarely –210) µm; alar cells few, moderately inflated. Costa highly variable, ending below apex, percurrent to long excurrent (often variable within a population or even a single plant), (30–)36–45(–60) µm wide near base. Axillary hairs present.

Autoicous. Perigonia and perichaetia as per genus. Setae variable in length, 4–22(–30) mm, weakly dextrorse throughout, pale red-brown, weakly hygroscopic; capsules erect, symmetric, obovoid-cylindric or obovoid (in var. gracilis), or occasionally narrowly pyriform (in var. subnudus), (1.3–)1.5–2.0 mm (in var. gracilis; to 2.5 mm in var. subnudus) with a neck c. ⅓ the capsule length (to c. ½ in var. subnudus), usually strongly constricted below mouth when dry; mouth equal the capsule diameter, transverse; exothecial cells elongate, 45–55(–75) µm, with obscure lumina in surface view, in cross-section with anticlinal walls strongly cuneate, c. 6–8 rows oblate at mouth; operculum plano-convex. Peristome double; exostome teeth variably developed, straight, red-brown, usually ± irregular in outline and with sinuose margins, (150–)180–225 × 45–60 µm, tapered to a slender or bilobed and often ± perforate apex, striate, weakly trabeculate, not appendiculate; endostome variable, rudimentary to well developed, rarely with fragments adhering to the upper inner surface of teeth or seemingly absent. Spores (27–)31–39(–41) µm, finely verrucate or lirate-murate (rarely gemmate), lacking a trilete scar.

The var. subnudus in accepted only from Australia; the report of this variety in N.Z. by Fife & Seppelt (2001) is based on a misidentification. Only the single (but variable) variety, var. gracilis, occurs in N.Z.

Too many intermediate specimens in Australian material occur between the typical variety and var. gracilis to permit the latter’s recognition at the specific level. The features noted in the key should allow placement for all but a small fraction of intermediate and/or aberrant specimens.