Pseudocyphellaria crocata (L.) Vainio

Gullprikklav

World distribution: Pseudocyphellaria crocata occurs in humid forests over most of the world. According to Degelius (1935) it is known from Europe, Africa, Asia, North America, South America, and Australia, as well as from many oceanic islands. It is probably most common in the southern hemisphere where it seems to have a broader ecological amplitude (cf. Galloway 1988, 1992). In Europe, it has an atlantic distribution and is known from Portugal (including the Azores and Madeira; Clauzade & Roux 1985; Hafellner 1992), the British Isles (Seaward & Hitch 1982, Purvis 1992f), and Norway (Ahlner 1948)

Ecology: Results. Indicated substrates include Picea abies (104), Sorbus aucuparia (45), moss covered rock walls (15), Alnus incana (13), Salix caprea (11), Salix aurita (3), Fraxinus excelsior (2), Populus tremula (2), Quercus sp. (1), and Betula sp. (1). Habitats are recorded at 142 localities. The majority are in coastal spruce forests (125; mostly in small brook ravines on marine sediments, along rivers, or in north- or east-facing slopes), but mixed deciduous forest (6), mixed coniferous/deciduous forest (5), old pasture with rock outcrops (3), north-facing maritime rocks (2), and a narrow canyon with deciduous trees (1) were also recorded as habitats. Although it has been recorded at altitudes up to 230 m, the majority of localities are situated below 100 m. Discussion. Pseudocyphellaria crocata favours humid and shaded habitats like north-facing moss covered rock walls and damp, sheltered woodlands (cf. Degelius 1935, Ahlner 1948). In forests, it seems to be confined to areas with long canopy continuity, such as fire- and storm-free refugia. It is usually accompanied by other oceanic foliose lichens, i.e. Degelia plumbea, Lobaria spp., Pannaria spp., and Sticta spp., and the Pseudocyphellaria crocata often indicates a species-rich environment with several rare lichens. The western and central Norwegian populations show somewhat different ecological characteristics. In central Norway P. crocata is almost exclusively an epiphytic lichen, most often growing on Picea abies, while in western Norway it occurs on moss covered rock walls and on deciduous trees. Ahlner (1948) emphasizes that Picea abies is the primary substrate for Pseudocyphellaria crocata in Trøndelag and that it is secondarily spreading onto neighbouring deciduous trees. In our opinion, however, it seems that the opposite is often true, particularly in the westernmost parts of Trøndelag were it is almost exclusively found on trunks of deciduous trees. Picea abies is a late immigrant to Trøndelag (Hafsten 1992), and it seems likely that the lichen was present here before the immigration of spruce. The largest known populations (1620, 1624, 3553) are on spruce. The populations on spruce are usually within or close to small brook ravines on marine sediments. The large foliose lichens referred to the 'Lobarion' are sensitive to low bark pH (Gauslaa 1985). It is possible that spruce growing on marine sediments have higher bark pH than trees growing in similar habitats, but on other sediments

Threats: Results. Recorded threats are forestry by clearcut logging (97), land development including road construction (10), collecting (8), agricultural expansion (6), overgrazing by elk (4), shading from dense spruce plantations (4), and pollution (2). Discussion. The strong decline of this species in the last fifty years seems mostly to be due to modern forestry, at least in central Norway. In western Norway effects of air pollution are difficult to estimate, and may be a major cause of the decline. In most of the localities the populations are rather small, consisting of a few individuals only

Status: 99 of the old localities were investigated. The species was found in 29 (often as rather small populations), regarded as extinct from 64, and of uncertain status in 6. Twenty-three new localities were discovered, primarily in Trøndelag. Three of the localities are within forest reserves (1496, 1623, 1624), but with a fairly large population only at Dølaelva (1624). In western Norway it has declined dramatically and is today known with certainty from only 4 localities, of which the largest consists of only 4 thalli (1484)

Specimens in other herbaria, litterature, etc.