Flora of New Zealand Series

Description : Thallus bright bluish, crustose, effuse, gelatinous, swelling when wet, cracking into areolae, up to 3 mm diam., on drying. Lobes, flattened, star-like, confluent, narrow, closely appressed to substratum. Thallus not markedly layered, appearing homoimerous, though with a thin cellular cortex. Photobiont Nostoc in curled chains, cells small, bright-blue to 5 μm diam. Apothecia abundant, to 2 mm diam., pale pinkish, sessile to immersed with a whitish proper exciple and occasionally with a secondary thalline exciple. Hymenium 100–120 μm tall, I+ reddish brown. Asci narrowly elongate, thin-walled with an indistinct apical ring structure. Proper exciple to 75 μm wide, of hyaline, conglutinate, unorientated hyphae. Subhymenium subparaplectenchymatous, to 40 μm thick. Ascospores ellipsoidal, 12–15 × 6–7 μm, with several unequal oil droplets. Pycnidia globose, semi-immersed, 80–100 μm diam., pinkish, with darker ostiole, Umbilicaria -type (Vobis 1980). Conidiophores short-celled. Conidia pleurogenous, bacillar, slightly thickened centrally, 3.5–5 × 1 μm.

Chemistry : TLC−, all reactions negative.

N: Northland (Three Kings Is, Tasman Valley, Te Huka, Church Road Scenic Reserve near Kaitaia), South Auckland (Waipapa Scenic Reserve, Waikato River). In northern, lowland coastal vegetation (Leptospermum scoparium, Vitex lucens) in humid, shaded habitats, among mosses on bark. Still rather poorly known in New Zealand. Known also from New South Wales in Australia (Jørgensen 1998b: 535–536; 2001b: 137; McCarthy 2003c, 2006).

Australasian

Illustrations : Jørgensen (1998b: 536, fig. 1A); Henssen (2000: 63, fig. 4).

Santessoniella pulchella is readily distinguished from all other species in the genus by its bright colours, a bluish thallus with beautifully (hence the epithet) contrasting pinkish apothecia. It differs from the brownish S. polychidioides (from Chile) in having a nearly crustose, not subfruticose thallus and immersed, flattened apothecia, occasionally with a secondary thalline margin.