Piętka, J., Byk, D. and Byk, A. 2021. Octopus stinkhorn Clathrus archeri (Berk.) Dring, an alien stinkhorn fungus (Phallaceae), in north-eastern Poland. Baltic Forestry 27(2): 174–179

    Distribution of an alien fungus, octopus stinkhorn Clathrus archeri, has been studied in north-eastern Poland. The closest earlier known localities of this species, situated north of the new ones, were reported near the village of Dymnica (Lębork County) in Poland and near the town of Kartena in Lithuania. Field research was conducted in May–November in 2019–2020 and information from naturalists and foresters was verified, to map this species and draw attention to the problem of appearance of alien fungal species in forests. In the locality, where the largest number of basidiomata was found, they were measured every day from 12 October till 2 November 2020: height and width of young ones at the egg phase, height of mature ones, and length of their longest arms. Additionally, arms of individual basidiomata were counted. We have documented 7 localities of C. archeri, including 5 situated in forests and 2 in other habitats. In total, we found 63 basidiomata of this species. In the localities outside forests, basidiomata of C. archeri appeared in places where timber was stored, and the soil was covered with sawdust and pieces of bark. The other 5 localities were situated in broadleaved forests with a small proportion of coniferous species. It seems that C. archeri, when moisture level is suitable, finds favourable living conditions in fertile broadleaved forests of north-eastern Poland. It is sometimes moved from forest areas, e.g. with wood, to open and urbanized areas. Considering the observed climate change, we can expect a further spread of C. archeri to the north-eastern of Poland and an increase in the number of its localities in the Baltic Sea region. Spore dispersal of this species is facilitated not only by humans but also by insects. No negative impact of C. archeri on wooded habitats was noticed.

Keywords: Phallaceae, Clathrus archeri, octopus stinkhorn, alien species, ecology, distribution, forest, Poland