Caloplaca rosei
=Caloplaca litoralis Zahlbr., Denkschr. Akad. Wiss. Wien math.-naturwiss. Kl. 104: 370 (1941).
Caloplaca litoralis. Lectotype: New Zealand. Wellington, Lyall Bay, on greywacke at high-tide mark, H.H. Allan A99 – CHR 373795 [fide Galloway (1985a: 68)].
Description : Thallus closely attached, orbicular to irregularly spreading, 1–3 cm diam., often confluent and forming extensive swards to 10–30 cm diam., continuous, even to uneven, minutely wrinkled, papillate or irregularly crumpled to regularly areolate; areolae angular, irregular, 0.5–1(–1.5) mm diam., separated by narrow to slightly gaping deep cracks (exposing substratum), cracking most noticeable centrally but also occasionally to commonly extending to margins; surface apricot-orange to orange-yellow, matt or slightly glossy in parts; prothallus in a thin to thick, fibrous, marginal zone, concolorous with or slightly paler than thallus, continuous or interrupted here and there with cracks. Apothecia scattered to numerous, commonly developed centrally, sessile, rounded to contorted through mutual pressure, 0.1–0.8(–1.2) mm diam., disc plane to subconvex, deep orange (noticeably darker than thallus), matt; thalline margin not apparent, restricted to a thin collar around disc at base, concolorous with thallus; proper margin persistent, obscuring disc at first, entire, slightly raised, glossy, concolorous with disc or paler. Epithecium yellow or brownish-orange, granular, 10–18 μm thick. Hymenium colourless, without oil droplets, 70–70(–85) μm tall. Paraphyses slender, 1.5–2 μm thick, submoniliform at apices, apical cells swollen to 4–5 μm diam., sometimes furcate. Asci cylindrical, (50–)60–70 × (10–)12–15 μm, 8-spored. Ascospores broadly ellipsoidal, apices pointed, (10–)11.2–13.5 × 5–6.5(–7) μm; septum 2–3.5 μm thick.
Chemistry : Thallus and apothecia K+ reddish purple; containing parietin (major) and lesser amounts of emodin, teloschistin and fallacinal (Arup 1992:153).
N: Northland (Three Kings Is, Mokohinau Is, Muriwhenua I., Chicken Is), Wellington (Kapiti I., Paekakariki, Titahi Bay, Makara, Lyall Bay, Wellington Airport coast). S: Marlborough (Paparoa Point), Otago (Otago Harbour, Taieri Mouth, Kaka Point, the Nuggets), Southland (Howells Point). Ch: (Okawa Point, Tapuangi-Monau Reef, Ellice Point Waitangi). Ant: (Hut Cove). On hard maritime rocks (often on steeply inclined to vertical surfaces) at high-tide level. Associating with Amandinea otagensis, Caloplaca circumlutosa, C. cribrosa, C. papanui, C. sublobulata sp., Opegrapha diaphoriza, Pertusaria graphica and Xanthoria ligulata. Known also from the west coast of North America from British Columbia to Baja California (Arup 1992: 155, fig. 8).
Circum-Pacific
Illustrations : Arup (1992: 154, figs 4–7; 1995b: 135, fig. 21).
Caloplaca rosei is characterised by: the saxicolous (coastal rocks) habit; the orbicular to irregularly spreading, areolate thallus; the apricot-orange to orange-yellow, matt or slightly glossy surface; a thin to thick, fibrous prothallus in a well-defined marginal zone, concolorous with or slightly paler than thallus; scattered to numerous central apothecia, 0.1–0.8(–1.2) mm diam., the disc deep-orange noticeably darker than thallus; a hymenium without oil droplets, 70–70(–85) μm tall; cylindrical asci (50–)60–70 × (10–)12–15 μm; and broadly ellipsoidal ascospores with apices pointed, (10–)11.2–13.5 × 5–6.5(–7) μm; septum 2–3.5 μm thick. It is distinguished from C. circumlutosa by colour, texture of upper surface, size of apothecia, colour of prothallus, and size of ascospores.
