Lower Devonian bryozoan faunas are rich and diverse worldwide; however, our knowledge is often restricted due to outdated taxonomy and patchy descriptions. In North America, Lower Devonian bryozoans have been mainly reported from New York State and Maryland, whereas contemporary faunas from other states have remained unstudied. The present paper describes eight cryptostome bryozoan species belonging to six genera from the Birdsong Shale of the Ross Formation (Lower Devonian, Lochkovian) of Tennessee, USA. They include Callotrypa unispina (Hall, 1874), Orthopora ovatipora (Hall, 1879), O. rhombifera (Hall, 1874), Bactropora aequalis sp. nov. and B. parva sp. nov., as well as three new combinations: Ensipora lirata (Hall, 1874) n. comb., Lepidotrypa rhomboidea (Hall, 1881) n. comb., and Hagemanella granatula (Hall & SimpSon, 1887) n. comb. Two genera are new: Lepidotrypa gen. nov. and Hagemanella gen. nov. The studied fauna is restricted to the Lower Devonian of North America. The bryozoan growth forms present are characteristic of quiet and shallow environments of the inner to middle shelf. Morphological and nomenclatural problems of cryptostome bryozoans are discussed.
An overview of a newly collected, rich Middle Miocene Muricidae assemblage from the Pannonian Basin (Letk & eacute;s, Hungary) is presented. Extended palaeogeographical distributions of several muricids are reported, and five new Muricidae species are described as new for science: Ocenebra inzanii n. sp., Attiliosa juditae n. sp., Coralliophila janosi n. sp., Flexopteron agnesae n. sp., and Phyllocoma letkesensis n. sp. The study area with 78 species is characterized by an exceptional high diversity of the Muricidae in the Miocene Central Paratethys.
Here we describe the new genus and species of Blattinopsidae, Palatinopsis daliamarquesae, from the Rotliegend Group (early Permian; Asselian) of the Saar-Nahe Basin (Rhineland-Palatinate, Germany). It can be separated from the other genera of this family by the numerous branches of RP, M and the presence of a posterior branch of CuA situated opposite to the base of RP.
Larger symbiont-bearing benthic foraminifera (LBF) are among the most important carbonate-producing protists in tropical and subtropical shallow-marine ecosystems. Their distribution is governed by a complex interplay of environmental factors that directly affect host physiology, calcification, and the performance of their photosynthetic endosymbionts. Understanding the environmental envelopes occupied by modern LBF is therefore essential not only for predicting their responses to ongoing climate change but also for interpreting fossil assemblages and reconstructing past marine environments. This study presents a comprehensive global analysis of environmental tolerance ranges in 74 species of modern LBF based on more than 4,760 occurrence records collected from tropical and subtropical oceans worldwide. Occurrence data were integrated with environmental datasets including sea-surface temperature, phosphate, nitrate, salinity, current velocity, chlorophyll-related productivity proxies, and diffuse attenuation coefficients to identify the realized environmental limits and ecological niches occupied by extant taxa. Temperature emerged as one of the strongest determinants of LBF distribution. Species occupied environments spanning absolute thermal extremes from 8.5 degrees C to 34.4 degrees C, although substantial differences were observed among species, genera, families, and symbiont types. Peneroplid taxa hosting rhodophycean symbionts exhibited the broadest thermal envelopes, whereas several calcarinid and a few other LBF taxa displayed narrow stenothermal niches indicative of strong specialization to stable tropical conditions. Importantly, minimum temperature thresholds varied far more strongly among taxa than maximum temperatures, suggesting that cold-season conditions exert a stronger influence on largescale biogeographic distributions than episodic warm extremes. Nutrient-related parameters revealed similarly pronounced ecological differentiation. Phosphate and nitrate tolerances varied widely among taxa and demonstrated that niche differentiation is largely controlled by lower nutrient thresholds rather than upper limits. Many LBF species are capable of surviving under extremely oligotrophic conditions, reflecting the efficiency of host-symbiont nutrient recycling systems. Nevertheless, several genera exhibited surprisingly broad nutrient tolerances and persisted under elevated phosphate and nitrate concentrations, indicating substantial ecological plasticity. Diatom-bearing taxa generally displayed the broadest nutrient niches, whereas dinoflagellate-and chlorophyte-bearing taxa tended to occupy narrower nutrient regimes associated with stable carbonate platform environments. Diffuse attenuation coefficients highlighted the importance of light availability as a major ecological constraint on photosymbiotic foraminifera. Species hosting diatoms and rhodophycean symbionts occupied the broadest attenuation ranges and extended into deeper or more turbid habitats, whereas chlorophycean-bearing taxa were largely restricted to shallow or highly transparent waters. These patterns demonstrate that symbiont identity strongly influences the ability of LBF to exploit different positions along the light gradient and contributes substantially to niche differentiation among taxa. Salinity tolerances revealed additional ecological partitioning. While many species occupied relatively stable oceanic salinity conditions, several taxa displayed remarkable euryhalinity and were able to persist across large salinity gradients characteristic of lagoons, reef flats, and nearshore environments. Family-level analyses demonstrated that Amphisteginidae and Nummulitidae exhibit particularly broad salinity tolerances, whereas other lineages are more restricted to fully marine conditions. Current velocity emerged as an additional factor contributing to ecological differentiation among larger benthic foraminifera. Species occupied environments ranging from very low-energy lagoonal settings to high-energy reef-front and platform-margin environments characterized by strong water movement. Taxa associated with elevated current velocities generally exhibited broad ecological tolerances and frequently occurred in habitats where enhanced water circulation promotes nutrient exchange, oxygen supply, removal of sediment particles, and efficient dispersal of propagules. Conversely, several species were largely restricted to low-energy settings where reduced hydrodynamic stress favors stable substrate conditions and minimizes physical disturbance. Differences among species, families, and symbiont groups indicate that hydrodynamic conditions constitute an important component of the multidimensional environmental niche occupied by larger benthic foraminifera. The ability to tolerate varying flow regimes further contributes to the ecological success of some taxa and helps explain their broad geographic distributions across diverse shallow-marine environments. Taken together, the results demonstrate that LBF distributions are structured by a multidimensional environmental niche in which temperature, nutrient availability, light penetration, salinity, chlorophyll-a and hydrodynamic conditions interact to determine species occurrence. The analyses further reveal that environmental tolerances are strongly influenced by phylogenetic history and symbiont identity, producing distinct ecological strategies ranging from highly specialized stenotopic taxa to broadly adaptable environmental generalists. Importantly, the minimum and maximum values reported here should not be interpreted as optimum habitat conditions. Rather, they represent the environmental extremes encountered within the global distributions of the species and therefore define realized tolerance limits that may only be experienced seasonally or episodically. Consequently, the central portions of these environmental envelopes likely provide a more accurate representation of typical living conditions. The resulting dataset provides one of the most comprehensive actualistic frameworks currently available for modern larger benthic foraminifera. Beyond improving predictions of future responses to ocean warming and environmental change, these modern ecological relationships offer a powerful tool for paleoenvironmental reconstruction. Because fossil larger foraminiferal assemblages preserve taxonomic, functional, and symbiotic signals linked to environmental conditions, the ecological patterns documented in modern oceans can be used to infer past temperatures, nutrient regimes, water transparency, and salinity conditions with increased confidence. The study therefore establishes a robust foundation for both modern ecological forecasting and interpretation of the geological record.
Bajocian crinoids are described for the first time from the Mecsek Mountains, Hungary. The assemblage comprises Cyrtocrinida indet., Lonchocrinus sp., Phyllocrinus malbosianus, Ph. stellaris, Balanocrinus inornatus, and is assigned to the uppermost Bajocian Bomfordi/Dimorphus Subzone of the Parkinsoni Zone based on the co-occurring ammonite Dimorphinites dimorphus. The crinoid assemblage was deposited in a shallow bathyal environment and contains a mixture of shallow- and deeper-water faunal elements affected by transport and taphonomic reworking. It shows close similarities to the lower Bathonian crinoid fauna from the nearby Hidasi Valley (Mecsek microcontinent) exhibits affinities with the crinoid faunas of the northern shelf regions of the Western Tethys. Despite its low taxonomic diversity, the assemblage provides important insight into the distribution of latest Bajocian crinoids and the palaeoenvironmental conditions along the northern margin of the Western Tethys.
