Temporal and spatial distribution patterns of dipteran assemblages in common teasel (Dipsacus fullonum L.) phytotelmata: Insights from eastern Slovakia

The common teasel (Dipsacus fullonum L.) represents a unique and almost unknown aquatic ecosystem referred to as phytotelma, identified almost a century ago by Varga in 1928. The present study investigates the ecology of dipterans inhabiting the phytotelmata of the teasel in eastern Slovakia. The research, conducted from May to August (11.5.2016 – 16.8.2016), focused on the temporal and spatial distribution of organisms, mainly Dasyhelea spp. (Ceratopogonidae) and Metriocnemus eurynotus (Holmgren, 1883) (Chironomidae), in the phytotelmata. A total of 1429 dipteran individuals from six families were identified, with Dasyhelea spp. and M. eurynotus dominating the samples. The temporal and spatial dynamics of the larval and pupal stages were observed. M. eurynotus occurred mainly in the lower levels early in the season and Dasyhelea entered the higher levels during the M. eurynotus abundance decline. Unexpectedly, Dasyhelea pupae were observed actively moving out of the water on the plant stems between phytotelmata levels. The study highlights the simplicity and extremity of the teasel aquatic environment and provides insights into ecological processes, such as distribution, colonisation and species interactions within the teasel ecosystem. The results contribute to the broader understanding of phytotelma ecology and highlight the importance of the common teasel as a unique habitat for dipteran communities.