Leaves of lower stem triangular-lanceolate, appearing rigid, c. 1.0–1.2 × 0.25–0.3 mm, erect-spreading; mid laminal cells firm-walled and oblong-rectangular, smooth, c. 24–39 × 9–12 μm, those in the basal corners gradually becoming short-rectangular or quadrate, c. 10–15 × 12 μm and extending up the leaf margins in 2–4 rows; costa stout, occupying ⅓ or more of leaf base, percurrent or ± filling the upper ⅓ of leaf and short excurrent, in cross-section lacking stereids or other differentiated cells; leaves of innovations sometimes longer (c. 1.4–1.5 mm) and more wide-spreading.

Perichaetial leaves c. 1.2 × 0.25 mm, triangular-lanceolate or lanceolate from a ± ovate base, plane or weakly recurved, entire.

Distribution NI: N Auckland (Ahipara, Moturoa I. and associated Black Rocks); Ch (Ōtauwae Covenant).

At Black Rocks the best documented collections came from damp or waterlogged depressions on an exposed basalt platform on the Northwest Crater Rim (one of the Black Rocks), where it was associated with Campylopus introflexus and Ceratodon purpureus†and the flowering plants Disphyma australe and Astelia banksii.

de Lange) was a “dark brown wispy moss” growing “extremely exposed to southerly storms”.

At Ahipara “most of the likely habitat is now invaded by kikuyu grass Pennisetum clandestinum and it is possible [that A elatum] is no longer present at the type locality” (J.E.

Recognition Unfortunately known only from non-fruiting material, this species is exceedingly inconspicuous and possibly overlooked at other coastal sites.

It is best recognised by its formation of numerous innovative branches, the zig-zag appearance of its stems, its ± wide-spreading, strongly costate leaves, and its occurrence on coastal rocks.

Strips of stem cortical cells typically adhere to the costal base when leaves are removed.

long, erecto-patent above, more widely spreading below, from a widened base lanceolate-subulate, concave, entire or indis-tinetly crenulate towards the apex; margins plane or rather narrowly recurved.

This species, probably the most robust of the genus, was collected by H. B. Matthews on coastal rocks at Ahipara, Northland, and has not been rediscovered.