Roccellina exspectata
Description : Thallus crustose at first, becoming swollen, bullate, the bullate parts readily separated from substratum, creamish yellow to creamish brown often with a greenish tinge, slightly pruinose or subglabrous, 0.7–1.5(–5) mm thick. Cortex well-developed with mixed and intertwined hyaline hyphae in an opaque brownish, granular, gelatinous matrix, 20–40 m thick. Photobiont Trentepohlia. Medulla white to rust-brown in upper parts and brown to brown-black in lower parts. Soralia laminal, punctiform to maculiform or capitate-globose, 0,1–2.5 mm diam. Apothecia not seen in New Zealand material.
Chemistry : Cortex K−, C+ red, KC+ red, Pd−; medulla upper part C+ red; containing lecanoric acid.
N: Northland (Three Kings Is; Black Rocks off Moturoa Is, Aorangi I., Poor Knights Is, Hen I.). On coastal rocks and cliffs, s.l. to 100 m. Also on Curtis I., Bass Strait, Australia (Tehler 1983; Tehler et al. 1991: 403–404; McCarthy 2003c, 2006). Associating on the Three Kings cliffs with Haematomma fenzlianum.
Australasian
Illustration : Tehler (1983: 48, fig. 30).
Roccellina exspectata is restricted to maritime rocks, and is characterised by the subcrustose, bullate, creamish brown to yellow-brown, sorediate, consistently sterile thalli that react C+ red (lecanoric acid). The medulla is slightly whitish-rusty to brownish in upper parts, the lower hypomedulla being brown to dark-brown.
