Assemblages of adult Odonata were studied in four intermittent karst rivers encompassing macrophyte-rich (MRH) and macrophyte-poor habitats (MPH) in southern Europe, where temporary lotic habitats are the predominant freshwater type but are still understudied. With a total of 25 recorded species, the studied habitats support species-rich Odonata assemblages, as already shown for intermittent rivers in the Mediterranean. Aquatic macrophyte abundance, conductivity, and water velocity are the most significant determinants of Odonata assemblages in the studied IRES. MRH promote higher Odonata abundance and the taxonomic and functional diversity of their assemblages compared to the MPH. Odonata assemblages in MRH are characterized by higher values of body size and a higher share of species preferring lentic and temporary hydrological conditions. Moreover, their assemblages are characterized by various patterns of nymphal development and drought resilience strategies. In contrast, MPH are preferred by lotic species, with nymphal development all year round and with no specific drought-resisting strategies. Our results contribute to the knowledge of diversity and ecological requirements of dragonflies and damselflies in IRES habitats, which could provide scientific background for future conservation activities and bioassessment protocols of such habitats and their biota.

(2020). New national and regional bryophyte records, 62. Journal of Bryology. Ahead of Print.

A comprehensive survey of Croatian watercourses covering the whole of the national territory and investigating inherent watercourse heterogeneity was conducted to explore the ecological responses of the most frequent freshwater bryophytes with respect to water chemistry variables and land use within the catchment area. Direct multivariate ordination (CCA) of vegetation data paired with 18 environmental variables revealed that freshwater bryophytes and their assemblages were segregated along the gradients of water chemistry and the proportion of natural and urban area within the catchment. Generalized additive models (GAM) were employed to explore the ecological responses of individual species. The results showed that most of the investigated species preferred natural, clean, well-oxygenated watercourses, with low nutrient and organic matter content, as well as with low electrical conductivity. Species such as Palustriella falcata, Eucladium vertcillatum, Dichodontium flavescens and Jungermannia atrovirens had narrow ecological niches and were restricted to pristine watercourses, while the most frequent and widely distributed species, such as Fontinalis antipyretica, Rhynchostegium riparioides, Cratoneuron filicinum, Fissidens crassipes, Cinclidotus fontinaloides and C. riparius, had a wide ecological tolerance. Riccia fluitans and Leptodyctium riparium had wide ecological ranges, but with optima in hypereutrophic waters with high nutrient and organic content, as well as high electrical conductivity. Furthermore, these two species were frequently associated with a high share of intensive agriculture and a low share of natural land within the catchment.

Hornworts are globally the least diverse bryophyte group with respect to species number, with only eight species known from Europe. As for Croatia, only two species are listed in the available literature, with most recent record being more than 85 years old. Our study carried out in Central Croatia identified three new species for the hornwort flora, including two new genera – Notothylas Sull. ex. A. Gray and Anthoceros L. Our finding of very rare Natura 2000 species Notothylas orbicularis (Schwein.) A. Gray, reported hitherto only from four Central European countries, is the first in Southeast Europe and the southernmost in Europe. Furthermore, we recorded Anthoceros agrestis Paton and Phaeoceros carolinianus (Michx.) Prosk., which are either very rare or, more likely, overlooked and understudied in Southeast Europe.

Within the course of a recent, extensive bryophyte survey across the whole country, eight moss taxa have been recorded for the first time in Croatia: Conardia compacta (Drumm. ex Müll. Hal.) H. Rob., Cynodontium tenellum (Schimp.) Limpr., Dichodontium flavescens (Dicks.) Lindb., Fissidens fontanus (Bach. Pyl.) Steud., Orthotrichum philibertii Venturi, Rhabdoweisia crispata (Dicks.) Lindb., Schistidium trichodon (Brid.) Poelt var. trichodon and Tortella fasciculata (Culm.) Culm.. In addition, new localities of five rare taxa are presented: Didymodon tophaceus subsp. sicculus (M.J. Cano, Ros, García-Zam. & J. Guerra) Jan Kučera, Ephemerum serratum (Hedw.) Hampe, Mannia triandra (Scop.) Grolle, Oxystegus tenuirostris (Hook. & Taylor) A.J.E. Sm. and Sphaerocarpos michelii Bellardi. Ecological and chorological data are provided for each of the reported taxa. Concluding, at the current state of knowledge, Croatian bryoflora includes 705 taxa, out of which 541 mosses, 162 liverworts and two hornworts.