The western border region of Hungary, including Kőszeg and its surroundings, is a poorly documented region from an algal point of view. The first reason for this is that the major standing water bodies found here are all artificial and relatively young in age. However, in the absence of other natural water bodies, they are important as potential wetland habitats, as is the information needed to conserve them. The present paper is the first to describe the algal flora of Téglagyári-tó in Kőszeg in the context of the planned process of processing lakes and reservoirs in the area. Despite its small size and the distur­bance caused by its recreational use, Téglagyári-tó is a species-rich, highly diverse habitat in terms of algal diversity. The Chlorophyta division accounts for the majority of the species recorded, but the Charopyta, Euglenophyta and Heterocontophyta divisions also make a significant contribution. Its value is particu­larly enhanced by rare species (e.g. Stauridium privum, Cosmarium sinostegos var. obtusius), not to ment­ion the red-listed endangered species (Cosmarium anceps, Cylindrocystis brebissonii, Euastrum bidentatum, Euastrum denticulatum, Penium spirostriolatum, Staurastrum oxyacanthum, Staurastrum tetracerum). A special feature is the presence of desmids (Euastrum biverrucosum, Euastrum minimum, Staurastrum levanderi var. hollandicum), which are not yet recorded in the region, and which colonise the slightly alka­line mesotrophic environment of the lake, otherwise known from a more acidic eutrophic environment. As a curiosity, Entomoneis ornata should be mentioned, which was identified in an environment associa­ted with higher salinity waters and only moderately loaded with inorganic nutrients.

The paper discusses the bryophyte flora of 77 sites in the Mecsek Mountains, mainly in deeper valleys. It includes species that are new to the area’s flora and/or endangered in Hungary, as well as mosses that have become more widespread or locally abundant compared to data from 1968 and 1983. The names of the locations, their geographical centers (centroids), and the grid unit IDs of the Hungarian Flora Mapping Programme (HFMP), where the sites are located, are listed and refer­enced according to their number in the list. Some of the species are national rarities, such as Scleropo­dium touretii, newly recorded in the Mecsek in 2023. Its second known occurrence in Hungary is re­ported in the Enumeration. We detail the occurrences of several species new to South Transdanubia, including Dicranum spurium, Diplophyllum albicans, Hypnum jutlandicum, Isothecium myosuroides, Kindbergia praelonga, Rhynchostegiella curviseta, Riccardia palmata, and Sciuro-hypnum plumosum. Additionally, species newly recorded from the Mecsek Mountains include Fontinalis antipyretica, Lepto­don smithii, Plagiomnium ellipticum, Pseudocampylium radicale, and Tortula brevissima. For two taxa, we present data of importance not only for the Mecsek, but also for the North-Hungarian Mts: Riccardia palmata, new for the Tornai-karszt, and Dicranum spurium, for which we confirm a very old record in the Zemplén Mts. We also note the widespread, sometimes massive occurrence of some aquatic and subaquatic mosses, e.g. Rhynchostegiella teneriffae, Hygrohypnum luridum, which have been recorded only once in the mountains in the last 50 years. The taxonomically uncertain Hygroamblystegium fluvia­tile with similar habitat requirements can now be found widely throughout the mountains. New popu­lations of Palustriella commutata, considered endangered and declining in the country, have been found in the Mecsek. The expansion of (sub-)aquatic species is particularly surprising in the light of recent hydroecological studies indicating that the streams in the Mecsek are drying up. The situation is similar regarding Rhynchostegium rotundifolium, previously thought to be a Tilio-Acerion (slope and ravine forest) species, which is legally protected in Hungary and only had one record from the Mecsek in the last century. This forest species is now found in peri-urban, sub-urban, slightly to moderately disturbed and secondary habitats throughout the mountains. Similar to its preference in Germany, outside of semi-natural habitats it occurs mainly on built structures in forest edges, ruins, abandoned mine sites, often in stands mixed with black locust and contaminated with litter. Microeurhynchium pumilum, which prefers sub-Mediterranean and sub-Atlantic climate, shady and humid habitats, has become one of the most widespread and abundant forest bryophytes in the Mecsek, in contrast to its few records 60 years ago. Half (50%) of the new mosses in the flora of the Mecsek can be connected to the cooler bore­al biome, while 21% is associated with the milder Mediterranean-Atlantic biome. The average of MAT (mean annual daily mean air temperatures averaged over one year) and MAP (accumulated precipita­tion amount over one year) of the 14 new species according to BET (Bryophytes of Europe Traits) indi­cates areas with much lower temperatures (7.7°C) than in Hungary, but with precipitation conditions (749 mm) similar to those in the Mecsek. The vast majority of the new species are extremely rare in Hungary, and are inconsistent with current climate warming trends. In contrast to the mosses with striking increase in records, the detection of new species is likely due to chance, in addition to system­atic research at finer spatial scales, rather than to local expansion of the species. However, in the case of expanding and abundant species, it is still an open question whether their dynamics compared to 40-60 year old references are apparent or real: the result of sampling bias in previous surveys or a conse­quence of climate change. In any case, the abundance of the above mentioned bryophytes in the Mecsek is not consistent with their current Hungarian Red List threat classification, and this cannot be attribut­ed to changes in definitions since 2010. The detected distribution and abundance, as well as the in­crease in the number of new species in the country within a decade, highlights the need for an updated Red List of Hungarian bryophytes.

The study reports 26 new occurrences of Dryopteris borreri (Newman) Oberh. & Tavel, a member of the Dryopteris affinis group, from the Southern Nyírség region (eastern Hungary) and a few additional records from other regions. Some morphological characteristics are also discussed that facilitate field identification. Most of the specimens were found in pine plantations, but they also occurred in oak, poplar, and black locust stands. The species was frequently associated with D. filix-mas and often grew on anthropogenically disturbed soils. In addition, new chorological records are provided for several other fern species, including Gymnocarpium dryopteris, Polystichum aculeatum, P. setiferum, Asplenium adiantum-nigrum, and Cystopteris fragilis.

Previously unknown occurrences of Buglossoides rochelii (Friv.) Stoyanov, Mátis & Sennikov (≡ Lithospermum rochelii Friv.) have been identified in the Pannonian Plain, based on field investigations and a critical revision of the genus Buglossoides in the major herbarium collections of Hungary and Serbia. In both its eastern range and the Pannonian Basin, the species predominantly occurs as a psammophyte. This paper summarizes its historical distribution in Hungary and Serbia, and provides new data on the current status of its habitats and populations in Serbia.

This paper presents significant floristic records from recent years in the northern part of Pest County and the western part of Nógrád County. The 100 occurrences represent 54 species, of which three are pteridophytes and 51 are flowering plants. The occurrences are new at least at the microre­gional level or, in some cases, confirm old or uncertain records. Fifteen species are newly recorded or have significant new data for the North Hungarian Mountains. Most of the species are aliens or native plants showing secondary spread along roads. For several of them, a northward expansion of their distribution in Hungary has been identified.

In this compilation we present the first occurrences of 22 vascular plant species not previ­ously documented from the territory of Hungary. Fifteen of the species are casuals, while seven of them are already naturalised, at least locally. We report the mass appearance and naturalization of Sagina maritima and the emergence of Carduus pycnocephalus along roadsides, single sites of Chaenorhinum litorale and Solanum elaeagnifolium near railway lines, and the localities of Lepidium latifolium and Sisymbrium volgense in various disturbed habitats, and some occurrences of Acalypha virginica in ur­ban environments. The first record of Bacopa rotundifolia is from a rice field, while that of Hydrocotyle sibthorpioides is from an urban lawn, and Senna tora occurred on construction debris. Among the spe­cies that appeared spontaneously as a result of earlier planting, Celastrus orbiculatus forms a natural­ized population in a tree plantation, Hygrophila triflora and Pontederia cordata are present in artificial canals and lakes, and Cenchus longisetus has become naturalised and is spreading along the banks of the Danube in Szentendre. Most other species are associated with trampled or heavily disturbed habi­tats in built-up areas (pavement edges, fences, ruderal areas). Alnus cordata, Eryobotria japonica, Euon­ymus alatus, Paxistima canbyi, Pistacia terebinthus and Solanum pseudocapsicum are present as casuals, while Viola palmata has become naturalised in built-up environments. The naturalisation process of Allium aflatunense on a private property has also been documented.