Flora of New Zealand Series

≡Gyalideopsis zeylandica Vězda & Malcolm, Australas. Lichenol. Newsl. 40: 20 (1997).

Holotype: New Zealand. Nelson, Pig Valley Road, 0.3 km W of Wairoa Gorge Road junction, 120 m, 41º27.3's, 173º4.8'E, NZMS 260 M27: 168727, on exposed siliceous rock of disturbed road cutting, 23.ix.1994, W. Malcolm2012 – CHR 487298. Isotypes – BM, CANB, DUKE, ESS, GZU, H, HO, M, PRM, TSB, UPS, VBI, Herb. K. Kalb, Herb. A. Vězda.

Description : Thallus crustose, smooth or cracked, ashen white, without setae, verrucae or soralia. Photobiont Chlorococcaceae. Hyphophores Aulaxina -type, straight, cylindrical, 0.5 mm tall, furnished at apices with hyaline hyphae, palmately stretching outward and forward, and bearing bundles of diahyphae. Diahyphae hyaline, septate, moniliform, and fused. Apothecia rounded, lecideine, 0.5–0.75 mm diam., constricted at base, broadly sessile; disc brown-black; margins entire, wide, black, persistently raised. Exciple strongly developed laterally, c. 100 μm thick, brown-black. Hypothecium and medulla hyaline. Hymenium 60 μm tall, brown-black in epithecial zone, otherwise colourless. Asci 8-spored (sometimes 4–6-spored and then ascospores rather larger). Ascospores ellipsoidal, transversely septate, rarely submuriform, strongly constricted at septa, 12–16 × 4.5–6 μm.

S: Nelson. Known only from the type locality. On rock of disturbed road cutting.

Endemic

Illustrations : Vězda & Malcolm (1997: 21, fig. 1a–d – as Gyalideopsis zeylandica).

Exsiccati : Vězda (1997a: No. 264 – as Gyalideopsis zeylandica).

Lithogyalideopsis zeylandica is characterised by: the saxicolous habit; its regular, adnate and rather large apothecia (0.5–0.75 mm diam.) with a thick and black margin that is not radially cracked; 3-septate ascospores; and complex hyphophores composed of hyphal tufts on long hyphal branches. It is similar to the species G. vivantii Sérusiaux (Sérusiaux 1998c: 397) from Guadeloupe, and from G. lecideina Kalb & Vězda lb & Vězda 1988b: 41–42), and G. poeltii Vězda (Vězda 1983a: 155–156), both described from Brazil. Since all of these taxa have a black, carbonised apothecial margin and grow directly on rocks, and when known (G. poeltii, G. vivantii, G. zeylandica) have hyphophores of Aulaxina -type, it is possible that they represent a monophyletic group needing a separate generic circumscription (Sérusiaux 1998c). A recent phylogentic study formalised this group of taxa as Lithogyalideospis (Lücking et al. 2005: 144, 165).