Sarmatian and Pannonian mollusks from Pécs-Danitzpuszta, southern Hungary: a unique local faunal succession

As the almost 200-year palaeontological research revealed, the geographical distribution of various fossil mollusk faunas in deposits of the late Neogene Lake Pannon displays a regular pattern. The lake basin was filled by lateral accretion of sediments, resulting in condensed sedimentary successions in the distal parts of the basin and successively younger shallow-water deposits from the margins towards the basin center. Exposed intra-basin basement highs, however, broke this strict pattern when they acted as sediment sources during the lake’s lifetime. The Mecsek Mts in southern Hungary was such an island in Lake Pannon during the early late Miocene. Deposition of the 200 m thick Sarmatian–Pannonian sedimentary succession in Pécs-Danitzpuszta at the foot of the Mecsek Mts was thus controlled by local tectonic and sedimentary processes, resulting in a unique succession of facies and mollusk faunas. A typical, restricted marine Sarmatian fauna is followed by a distinct freshwater or oligohaline interval, which, according to micropalaeontological evidence, still belongs to the Sarmatian. Although poor preservation of fossils does not allow firm conclusions, it seems that freshwater Sarmatian snails were the ancestors of the brackish-water-adapted early Pannonian pulmonate snail taxa. The successive “Sarmatian-type” dwarfed cockle fauna is similar to those widely reported from the Sarmatian–Pannonian boundary in various parts of the Pannonian Basin; however, a thorough taxonomic study of its species is still lacking. The bulk of the sedimentary succession corresponds to the sublittoral to profundal “white marls,” which are widespread in the southern Pannonian Basin. In Croatia and Serbia, they are divided into the Lymnocardium praeponticum or Radix croatica Zone (11.6–11.4 Ma) below, and the Congeria banatica Zone (11.4–9.7 Ma) above; this division can be applied to the Pécs-Danitzpuszta succession as well. Sedimentation of the calcareous marl, however, ceased at Pécs-Danitzpuszta at about 10.5–10.2 Ma ago (during the younger part of the Lymnocardium schedelianum Chron), when silt was deposited with a diverse sublittoral mollusk fauna. Similar faunas are known from the Vienna Basin, southern Banat, and other marginal parts of the Pannonian Basin System, but not from Croatia and Serbia, where deposition of the deep-water white marls continued during this time. Finally, the Pécs-Danitzpuszta succession was capped with a thick, coarse-grained sand series that contains mollusk molds and casts representing a typical littoral assemblage. This littoral fauna is well-known from easternmost Austria, northern Serbia, and northwestern Romania, but never directly from above the sublittoral L. schedelianum Zone. The fauna is characteristic for the upper part of the Lymnocardium conjungens Zone and has an inferred age of ca. 10.2–10.0 Ma. The Pécs-Danitzpuszta succession thus allows to establish the chronostratigraphic relationship between mollusk faunas that have not been observed in one succession nor in close proximity to each other in other parts of the Pannonian Basin.

FAUNA AND DISTRIBUTION OF GASTROPOD AND BIVALVE MOLLUSKS (MOLLUSCA: GASTROPODA, BIVALVIA) IN THE LITTORAL ZONE OF THE FAR EAST MARINE BIOSPHERE RESERVE (PETER THE GREAT BAY, SEA OF JAPAN)

Aim. The littoral fauna of the Far East Marine Reserve was studied at the end of the last century; however, the monitoring studies of the malacofauna are relevant because of the increased recreational load and the threat of new species introduction. The aim of the work is to update the data on species composition and distribution of gastropods and bivalves on the littoral zone of the reserve.Methods. The material was collected during the monitoring studies in 2012-2014. The compilation of the collections and identification of the species were carried out according to standard methods. For the definition, conventional determinants and atlases were used.Results. As a result of the research, 49 species and taxa of mollusks were found, including 33 gastropods and 15 species and 1 hybrid of bivalves. New for the littoral fauna of the reserve were 13 species of Gastropoda, 3 species and 1 hybrid Bivalvia. It was established that the introduction of Atlantic mussel Mytilus galloprovincialis into benthic communities occurs through its hybridization with native species.Conclusion. The data obtained allows us to present a more complete picture of the biodiversity and distribution of the littoral malacofauna of the reserve, an integral part of Peter the Great Bay.

Niche sharing and spatial distribution in intertidal decapods on the rocky shores of Easter Island

The coastal marine ecosystems on Easter Island have been poorly studied, and the main studies were isolated species records based on the collections of scientific (primarily faunistic/floristic) expeditions. The aim of the present study was to apply a niche-sharing null model analysis on field observations of intertidal marine decapods on the rocky shores of Easter Island. The dominant species found were the decapods Planes minutus and Leptograpsus variegatus. The results of the null model analysis revealed that the species reported did not share an ecological niche, obviously corresponding to the absence of within-niche competition, and for P. minutus showed an aggregated pattern and negative binomial distribution, whereas L. variegatus had a uniform pattern and a binomial distribution. These results would agree with other, similar information about the littoral and sub-littoral fauna on Easter Island.

Palaeoecology, facies and stratigraphy of shallow marine macrofauna from the Upper Oligocene (Palaeogene) of the southern Pre-North Sea Basin of Astrup (NW Germany)

The 22 meter thick marine carbonate Upper Oligocene series of Astrup (NW Germany) is correlated with the Chattian type section of Doberg. It indicates a more constrained palaeogeographical and biostratigraphical position ranging from the biozones of Chlamys (C.) decussata (upper Chattian A) to Chlamys (C.) semistriatus (lower Chattian C). The macrofauna can be subdivided into three main benthic communities: A. the „coarse gravel spondylid beach fauna“ of the shore zone with „pebble beach facies“ dominated by sessile brachiopods, large balanids, spondylids, oysters or small regular echinoids. Borings are common in pebbles; B. the „glauconite fine gravel brachiopod-bryozoan littoral fauna“ of the shallow subtidal zone where a terebratulid/lithothamnid dominated fauna/flora is present. The rhodophyceans were most possibly anker stones and substrates for cirripeds and serpulids; C. the „glauconite carbonate sand phytal fauna“ of the shallow subtidal zone with a rich benthic mollusc dominated fauna. Indirect evidence for seagrass and macroalgae occurs on the attachment negatives of balanids and oysters, and also on Cibicides foraminifera or bryozoans like Cellepora. The facies types along the Wiehengebirge Island and Teutoburger Wald Peninsula coasts of the southern Pre-North Sea Basin differ with respect to their benthic communities to that of the siliciclastic Leipziger and the Rhenish Bay facies.

Benthic macroinvertebrate fauna of two alpine lakes over the last century: The value of historical data for interpreting environmental changes

Data on benthic macroinvertebrate assemblages of two alpine lakes in the Tatra Mts (Slovakia) collected in 1914, 1933, 1979–1982, 1993–1997, and 2000 were collated and analysed in an attempt to define their relationship to major environmental events affecting these alpine lakes over the last century. The oldest data were considered an important background before the onset of acidification in one of the lakes in the 1950s, while the most current contain possible information on biological recovery. Results show that data from the 1910s are insufficient to characterize the macroinvertebrate fauna. Deep zone assemblages of both studied lakes have remained stable since the 1930s. Changes in the density of dominant species over time were found in the acidified lake, suggesting a connection between an increase in phosphorus and chlorophyll-a concentration. The composition of the littoral assemblages in the acidified lake in the 1930s indicates that the lake was not strongly acidified at that time. A stable composition since the 1980s reflects the ongoing acid stress. Incomplete species data on the non-acidified lake did not allow us to detect possible changes in the littoral fauna related to acidification. Single findings of species indicating a recovery process need longer-term data to confirm such a trend. Results from this study suggest that historical datasets consist of valuable information that can supplement palaeolimnological analyses in the reconstruction of lake ontogeny.

Literature analysis and present state of knowledge of benthic Medusozoa (Cnidaria) from the Bay of Biscay and nearby areas (northeastern Atlantic), with emphasis on biodiversity

The literature on benthic Medusozoa (Cnidaria) from the Bay of Biscay and nearby areas (roughly between 42º–48º30’ N and 2°–10º W) is reviewed. Some 213 papers have been inventoried and classified in 17 groups based on their main contents. The present state of knowledge is analyzed, and papers covering each administrative territory of both adjacent countries, Spain and France, are listed. Around 2000, the accumulative curve of new papers and new records reached its ceiling. Some 205 species are known, with the suborder Conica (class Hydrozoa, order Leptothecata) accounting for the highest number of species (110), while the Proboscoida (Hydrozoa: Leptothecata), Filifera and Capitata (both Hydrozoa: Anthoathecata) account for much fewer species (21, 32 and 27 respectively). Only a few species are referable to the remaining subtaxa of Medusozoa, i.e. four to class Staurozoa, six to class Scyphozoa, four to subclass Trachylina (Hydrozoa), and one to order Limnomedusae (Hydrozoa). Species of suborders Capitata and Filifera (Hydrozoa, order Anthoathecata) will probably monopolize new discoveries of species. Knowledge of biodiversity is uneven amongst the different administrative provinces, with Guipúzcoa having the highest number of reported species (111 species, 54% of those known from the whole study area). Little information is available for certain areas, especially the French coasts. The fauna of every Spanish province has been the subject of MSc or PhD taxonomy-targeted research, but no such studies have been undertaken along the French coast. In Spain, the littoral fauna of Cantabria merits more intensive study because it represents an interface between the “cold” southwestern (from Asturias to Pontevedra) and “warm” southeastern (from Vizcaya to Gironde) areas of the Bay of Biscay.

The Dolichopodidae (Diptera) of the Galapagos Islands, with notes on the New World fauna

The Dolichopodidae (Diptera) of the Galápagos Islands (Ecuador) are reviewed. The fauna comprises 17 species, which are described, illustrated, and keyed. Further, relevant New World taxa are discussed, with information on diagnostic characters, species groupings and new synonyms. Nine species are newly described: Amblypsilopus depilis, Medetera galapagensis, Paraclius desenderi, Chrysotus baerti, Asyndetus wigginsi, A. maelfaiti, A. cavagnaroi, A. mystacinus, and A. bursericola. The following synonyms are newly established: Condylostylus longicornis (Fabricius) (=C. detitaticauda Van Duzee), Chrysotus brevicornis Van Duzee (= C. brevispina Van Duzee, = C. latifacies Van Duzee, = C. mexicanus Robinson), and Asyndetus tibialis (Thomson) (= A. ridiculus Parent). The ecology and origin of the Galápagos Dolichopodidae are discussed, and the fauna is regarded as an extension of the New World mainland coastal and littoral fauna. New distributional records from North and South America are included, and the systematic relationships of Galápagos species are discussed.