Acarospora versicolor Bagl. & Carestia, 1863

Westberg, Martin, Timdal, Einar, Asplund, Johan, Bendiksby, Mika, Reidar Haugan,, Jonsson, Fredrik, Larsson, Per, Odelvik, Goeran, Wedin, Mats & Millanes, Ana M., 2015, New records of lichenized and lichenicolous fungi in Scandinavia, MycoKeys 11, pp. 33-61 : 36-37

Acarospora versicolor Bagl. & Carestia, 1863

Acarospora versicolor Bagl. & Carestia. Comm. Soc. Critt. Ital. 1: 440. 1863.

Type.

ITALY. Piemonte. F. Baglietto s.n. (the location of the type is unknown according to Knudsen et al. in press).

Distribution.

New to Norway. Acarospora versicolor is widespread on both siliceous and calcareous rocks in Europe and western Asia and is in the Nordic countries known from one locality in Finland and one unconfirmed report from Denmark ( Alstrup et al. 1990, Knudsen et al. in press).

Acarospora versicolor belongs to the morphological group of brown Acarospora species lacking secondary metabolites. There are many names and many taxonomical problems in this group but A. versicolor was recently discussed and described in detail by Knudsen et al. (in press). Acarospora versicolor is identified by its white pruinose thallus and the negative C-reaction of the cortex. The thallus in A. versicolor is areolate and can become somewhat squamulose when well developed. It is mostly recognized by the presence of a white pruina on at least parts of the thallus (Fig. 3 ), but the pruina is sometimes lacking completely. The apothecia usually have a distinct margin and both the disc and the margin are typically darker than the thallus, sometimes almost black. It may then remind of a small form of A. badiofusca but the apothecia are not sessile as the mostly are in that species and there are several other character separating these species.

The Norwegian specimens reported here all grow calcareous rocks in sun-exposed habitats in the southern parts of the country. It is as far as we know the only one in this group of species in Scandinavia growing on calcareous rocks. However, elsewhere in Europe it also grows on non-calcareous rocks ( Knudsen et al. in press).

Specimens examined.

NORWAY. Buskerud: Hole, west side of the island Storøya, 60,04685°N, 10,2376°E. 8 June 2008, Westberg 08-092 ( S F268460); Oppland: Dovre, Hjelle, 62°03.21'N, 9°08.40'E, alt. 650 m. 10 Aug. 2010, Timdal 11757 ( O L-163814, filed under Lecidea degeliana ); Vågå, c. 300 m NE of the farm Viste, 61,86671°N, 9,02391°E. 13 June 2008, Westberg 08-198, 08-203, 08-205 ( S F268461, F268462, F268463).

Figures

Figure 3. Acarospora versicolor (S F 268463). Scale: 1 mm.