Porina constrictospora
Description : Thallus epilithic or epiphloeodal, continuous to rimose, medium to dark-green to greenish black, matt, smooth, 25–40 µm thick, ecorticate; prothallus not apparent. Photobiont Trentepohlia; cells 9–18 × 8–15 µm. Perithecia superficial, subglobose or bilaterally flattened, 0.32–0.56 mm diam., black; apex usually rounded; ostiole inconspicuous or in a papilla 30–50 µm wide. Involucrellum contiguous with or arching away from the exciple, sometimes incurved beneath, 50–70 µm thick, K+ reddish brown. Exciple 25–40 µm thick, dark-brown. Centrum 0.2–0.26 mm wide. Asci elongate-cylindrical, 80–115 × 7–12 µm. Ascospores elongate, usually with a medial constriction, entwined in the asci, 7-septate, 40–59 × 2–3.5 µm; perispore usually not apparent. Pycnidia semi-immersed, 70–100 µm diam., black. Conidia bacillar to ±filiform, 3–5 × 0.7 µm.
S: Nelson (Pakawau Creek Road, Golden Bay). On smooth-barked shrubs. Known also from Tasmania where it grows mainly in cool temperate rainforest, rarely in minute quartzite fissures or on twigs in exposed subalpine–alpine habitats (McCarthy & Kantvilas 1993b; McCarthy 2001f: 122; 2003c; 2003d).
Australasian
Illustration : McCarthy & Kantvilas (1993b: 139, fig. 1).
Porina constrictospora is characterised by: the corticolous habit; the long, very narrow ascospores with gradually tapering ends and with a distinctive median constriction, hence the name of the specific epithet.
