Flora of New Zealand Series

Holotype: New Zealand.Wellington, Kaitoke Waterworks Reserve, N of Wellington, on Beilshmiedia tawa leaves in Melicytus ramifloris – Dacrycarpus dacrydioides forest, 25.iii.1995, B. Polly 4753 – WELT. Isotypes – B, CBG, GZU, LG, M. STU, UPS, TNS, VBI, A. Aptroot (Baarn), K. Kalb (Neumarkt), H.T. Lumbsch (Essen), A. Vězda (Brno) [distributed in R. Lücking, Lichenes Foliicoli Exsiccati. Fasc. 6, No. 147 (1995)].

Description : Thallus subcuticular, semicircular, growing on leaf margins or on leaf scars, 0.5(–2)-cm diam., of small, rounded lobes at margins, bright-green to greyish green without a bluish tinge, smooth, glossy, without a prothallus, 10–15(–20) μm thick. Photobiont Cephaleuros, cells rectangular to ±rounded, 8–15 × 4–6 μm diam., yellow-green, in radiating rows and forming a horizontal plate within thallus. Perithecia abundant, black, hemispherical to subconical, solitary or appearing aggregated or fused by a conspicuous, black involucrellum covering 5–6 perithecia, but perithecia never fused, keeping their own ostiole; individual perithecia 0.4–0.5 mm diam., aggregating in groups to 1.3 mm diam. Involucrellum spreading between upper surface of host cells and thallus forming an irregular, subhorizontal plate around perithecia, 0.3–0.4 mm wide and to 150 μm thick; outer wall black, heavily carbonised. Exciple pale-brown, <10 μm thick. Centrum somewhat flattened, 240–250 × 140–160 μm diam. Paraphyses simple or sparingly branched. Asci cylindrical, 85–90 × 8–9 μm, lateral walls thin, apex distinctly thickened, with a small ocular chamber. Ascospores 8 per ascus, uniseriate, fusiform, the apices rounded, 1-septate, the distal end slightly larger than the proximal end, 1–3 oil droplets in each cell, slightly constricted at septum, not breaking in half, with small, cap-like or funnel-shaped gelatinous appendages at both ends, (12–)13–15 × 4.5–5.5 μm. Pycnidia of two kinds: (1) flat conical, black, glossy, 0.15–0.2 mm diam., conidiogenous cells ampulliform with a short, attenuated neck, 5 × 2 μm, producing numerous macroconidia subapically, narrowly ellipsoidal to bacillar or biclavate, 1-septate, distinctly narrower at septa, ends rather conical, with 1–2 oil bodies per cell, 9.5–10.5(–11) × 3–3.5 μm; (2) punctiform, black, 40 μm diam., producing bacillar to subellipsoidal microconidia, 2–3 × 1 μm.

N: Northland (Church Road Scenic Reserve near Kaitaia), Wellington (Kaitoke). On leaves of Beilschmiedia tawa.

Endemic

Illustrations : Sérusiaux & Polly (1996: 249, fig. 1; 250, figs 2–4); Malcolm & Malcolm (2000: 118).

Exsiccati : Lucking (1995c: No. 147).

Strigula kaitokensis is characterised by: the foliicolous habit; the large and expanding involucrellum joining several perithecia. Such an expanding involucrellum uniting several perithecia is known in several species of the related genus Phylloporis (q.v.); however, in this latter genus taxa are distinguished by the presence of Phycopeltis as photobiont, and by conical, acute perithecia that are very rarely aggregated.