Orcularia elixii Kalb & Giralt, sp. nov. Mycobank MB 563559

Sicut O. insperata, sed ascosporis minoribus differt.

Type:— Australia, New South Wales, Patonga, eastern side of Patonga Creek, ca. 40 km N of Sydney, on Avicennia marina at the edge of a mangrove forest; 33°33’S, 151°16’E, K. & A. Kalb 26226 & A. & P. Archer (CANB — holotype; hb. Kalb—isotype) .

Etymology:—The new species is named after our good friend and colleague John (Jack) Elix (Canberra) in honour of his many contributions to Austral lichenology.

Thallus corticolous, grey to dark-brownish grey because of a brown lichenicolous fungus growing on it, very thin, up to 80 µm thick, smooth to slightly warty. Prothallus absent. Algae chloroccoid 8–13 µm diam. Apothecia 0.15–0.25(–0.3) mm diam., lecideine, adnate to sessile, dark brown to black; disc dark brown or black, epruinose, concave to flat; proper margin thin, persistent. Proper exciple poorly developed, 25–40 µm thick, inner part colourless, outer part brown. Hypothecium 30–50(–70) µm high, brown. Hymenium 60–70 µm high, not inspersed. Epihymenium brown. Apical cells of the paraphyses 2–4 µm broad, brown. Asci 8- spored, Bacidia- type. Ascospores 1-septate, (10–)12–15(–16.5) × (5–)6–7.5(–8.5) µm, Orcularia - type, olive, later pale brown, spore wall smooth, young ascospores with lumina connected by a long isthmus; mature ascospores with a short isthmus or without isthmus connecting the lumina. Pycnidia and conidia not seen. Chemistry: Spot tests all negative, no lichen substances detected by TLC.

Notes:—The species is mainly characterized by the small apothecia and the small uni-septate ascospores. It is morphologically very close to O. insperata but differs by the smaller ascospores which further when mature have larger lumina (lateral inner walls less thickened).