Sticta lacera (Hook.f. & Taylor) Müll.Arg.
Cetraria lacera J.D. Hook. et Taylor, Hook. Lond. J. Bot. 3: 646 (1844).
Sticta filix var. parvula Nyl., J. Linn. Soc. Lond. Bot. 9: 247 (1866).
Lectotype: New Zealand, Sine loco. Mr Logan, BM!
S. filix var. parvula. Lectotype: New Zealand, Nelson, Tarndale. A. Sinclair, E!
Thallus 1-2(-3) cm tall, thin, fragile, easily fragmented when dry, erect or decumbent, spreading, lobate, stalked, attached by small, often proliferating root-like holdfasts, often forming extensive swards on bark or rocks. Lobes narrow, laciniate, ± strap-like 0.3-2 mm wide, highly dissected, margins entire, often minutely lobulate or phyllidiate, dichotomously to irregularly branched. Upper surface bright to pale green, olive to suffused-brownish, stalk darker, ribbed, flattened or ± terete, yellow-brown below, becoming distinctly orange- yellow on storage. Lower surface pale greenish to yellow-brown centrally and basally, white at margins, glossy, glabrous, minutely wrinkled, with a ± raised midrib to lobes. Cyphellae minute, pock-like, scattered, without a raised margin. Apothecia rather rare, sessile, solitary, towards lobe apices, 0.4-1.8 mm diam., disc plane to subconvex, matt, smooth, pale red-brown with a pale, waxy margin, thalline exciple massive, smooth to slightly verrucose-areolate. Ascospores fusiform, brown, 1-septate, 35-40(-95) × 7-10 µm.
N: Bay of Islands to Wellington. S: Nelson westwards to Jackson Bay, and Fiordland, eastwards from Banks Peninsula to Taieri Mouth. St: C: Among mosses on tree trunks in moderate shade in forested areas, on soil on rocks in humid sites, rarely on rocks in tussock grassland (Campbell I.), s.l. to 1000 m, coastal and inland.
Endemic
S. lacera is a small, fragile, highly dissected plant which has a small, often proliferating stalk, a character immediately distinguishing it from corticolous forms of S. martinii. The orange-yellow to ochre-brown pigmentation of the stalk and midrib (often more noticeable on storage) is characteristic as are the glabrous lower surface and the minute, pinprick-like cyphellae. The plant often forms extensive swards among mosses on tree bark or on stones on the forest floor.
