Flora of New Zealand Series

Description : Thallus inconspicuous, immersed, white to pale-grey, occasionally darker, smooth, continuous, with fine cracks radiating from the perithecia, delicately pitted, occasionally with a dark-brown prothallus. Perithecia 0.15–0.4 mm diam., almost entirely immersed, simple, black, apex 0.15–0.25 mm diam., subconvex. Ostiole depressed or inconspicuous. Involucrellum absent, the exciple being somewhat thickened near apex. Centrum obpyriform, 0.26–0.36 mm diam. Exciple medium-brown to brown-black, 15–22 μm thick. Ascospores 13–24 × 7–13 μm.

S: Canterbury (Milford). On limestone, associating with V. macrostoma, V. nigrescens and V. otagensis. Known also from throughout Eurasia, also from Ethiopia, North America, Cuba, and Australia (McCarthy 1991e, 2001j, 2003c: 182; Brodo et al. 2001).

Cosmopolitan

Illustrations : Zschacke (1934: 83, fig. 32); Ozenda & Clauzade (1970: 147, fig. 101); Brodo (1981: 60, fig. 27); Wirth (1995b: 959); Brodo et al. (2001: 727, pl. 896).

Verrucaria calciseda is an obligately calcicolous lichen having an inconspicuous, white to pale-grey endolithic thallus and simple, immersed perithecia, 0.15–0.4 mm diam., leaving a pit in the rock; ascospores 13–24 × 7–13 μm.