Verrucaria adguttata
Verrucaria adguttata is a species of crustose lichen in the family Verrucariaceae. It was first discovered growing on coastal rocks at Rangitoto Island near Auckland, where it tolerates the harsh conditions of salt spray and tidal influence. The species is be endemic to New Zealand's offshore islands.
Taxonomy
Verrucaria adguttata was formally described as a new species in 1941 by the German lichenologist Alexander Zahlbruckner. The type was collected by the New Zealand botanist Harry Allan.Description
The thallus grows on rock and forms scattered, rounded patches that are tightly adherent to the surface. Patches are very thin, smooth, and up to about 10 mm across, with slightly undulating margins. The colour is dark brown to nearly black and almost opaque; when wetted the surface becomes faintly gelatinous. No distinct is present. The is thin and brownish, made of densely interwoven fungal hyphae. The photosynthetic partner consists of bright-green, spherical algal cells 8–10 μm in diameter, arranged more or less in vertical series. Standard spot tests are negative.Fruiting bodies are small,, and glossy black, to about 0.25 mm in diameter, sitting free on the thallus and typically convex, with the pore only slightly depressed. The pale is capped by a sooty, hemispherical that is closely appressed almost to the base; it does not flare outwards and is truncate beneath. The internal tissue is colourless with confluent paraphyses; an iodine stain gives wine red to yellowish tones. Asci are plentiful, club-shaped, 8-spored, measuring to about 40 × 9–10 micrometres. Spores are hyaline,, straight, narrowly oblong-cylindrical with rounded ends, 9–11.5 × about 3 μm, generally arranged in two rows within the ascus. Asexual propagules are produced in small, half-immersed pycnidia with a shiny black top, 60–65 μm in diameter and a relatively wide pore. The conidia are very short, rod-shaped, straight to nearly straight, 2–3 μm long.