Flora of New Zealand Series

Thallus dimorphic. Primary thallus crustose, evanescent, rarely seen. Podetia repeatedly and intricately branched, dying at base, new growth initiated at apices, in matts or patches 2-200 cm diam., slender, not cupforming, lacking squamules or isidia, rarely sorediate, true cortex lacking, outer medullary layer with scattered to contiguous areolae or warts containing algae and forming a persistent or disintegrating pseudocortex. Photobiont green, Trebouxia. Inner medullary or cartilaginous layer well-developed. Apothecia small, pale to brown, peltate, in clusters at tips of branches. Pycnidia black, globose to cylindrical at the tips of terminal branchlets.

Although Cladina is considered by many authors to be a subgenus of Cladonia, [Martin T.R.S.N.Z. (Bot.) 85: 603-631 (1958); Ahti Annls Bot. Soc. Zool.-Bot. fenn. Vanamo 32 (1): 1-160 (1961); Thomson "The lichen genus Cladonia in North America". Univ. Toronto Press. pp. 172 (1968)], there is an increasing tendency to accord it generic status [Hale and Culberson Bryologist 73: 499-543 (1970); Brodo Bryologist 79: 385-405 (1976); Follmann Philippia 4: 34-37 (1979); Ahti Annls bot. fenn. 16: 228-236 (1979)] a view which is followed here. Cladina is a cosmopolitan genus of c. 40 species (the so-called "Reindeer lichens") being common in the circum-polar, coniferous belt of the Northern Hemisphere and in Nothofagus - dominated regions of the Southern Hemisphere, as well as in ice-free areas of tundra vegetation in both the Arctic and Antarctic. Cladina is also found in lowland, temperate areas and may be locally common in both subtropical and tropical regions. Ecological requirements of species appear to be ± uniform and they grow on organic and inorganic, acidic soils rather than on exposed rock surfaces, bark or rotten wood. The most detailed account of the distribution, habitats, morphology and taxonomy of Cladina is that of Ahti ( loc. cit., 1961). Two species occur in New Zealand.