Heterodermia spathulifera
Description : Thallus irregular to orbicular, to 3 cm diam. Lobes narrow, to 1 mm diam., plane not widening at apices, discrete to adjacent, firmly adnate, with marginal rhizines visible from above. Upper surface white or creamish, glossy, epruinose, sorediate. Soralia labriform, sometimes becoming large, to 5 mm tall, and spathulate, in humid sites developing into squamules aggregating centrally. Lower surface ecorticate, whitish at margins darkening to pale-brown centrally. Rhizines sparse, simple, 1–2 mm long, white or creamish, appearing as cilia on margins. Apothecia not seen.
Chemistry : Cortex K+ yellow, medulla K+ yellow, C−, KC−, Pd−; containing atranorin, zeorin and an unidentified compound ["spathulin"].
N: Northland (Kerikeri). On mangroves (Moberg 1999: 8). Known also from the Azores, (the Sonoran Desert in southern California/Mexico, the Caribbean, Asia, East and South Africa, and eastern Australia (Moberg & Purvis 1997; Moberg & Nash 2002; Moberg 2004a, 2004b: 265–266 – a map of the world distribution of this species is given on p. 265, fig. 1).
?Pantropical
Exsiccati : Moberg (1999: No. 270).
Illustration : Moberg & Purvis (1997: 192, fig. 2).
Heterodermia spathulifera is characterised by: the corticolous habit; the narrow, shiny, firmly attached lobes with pale rhizines; spathulate, large soralia; and a chemistry containing an unidentified compound "spathulin" appearing reddish in UV above zeorin after acid charring treatment.
