Unexpected abundance: Millepora corals in Late Pleistocene reefs of Egypt

<p>Coral reefs throughout the world are well known for the dominance of scleractinian corals. However, one group of hydrozoan corals can be very common in modern tropical coral reefs as well: <em>Millepora</em>, the fire coral. The modern Red Sea is particularly well known for its high abundances of <em>Millepora</em>, where the fire coral is dominant on current-exposed reefs. Yet, this hydrozoan has been described as rare in the fossil record throughout the world and the documented abundances in fossil reefs do not match the numbers from modern reefs. The main interpretation to explain this phenomenon so far has been a lower preservation potential of milleporids compared to scleractinians due to differences in skeletal structure.</p><p>During an investigation of six Eemian Egyptian reef sites (29 line intercept transects, typically of 20 m length) we found <em>Millepora</em> in 69% of the fossil reef transects. The abundances were comparable to the adjacent modern reefs (65.13% to 0.26%). Preservation of fossil <em>Millepora</em> was good to excellent and in some cases well-preserved pore characters allowed for identification to species level. Our findings seem to be in stark contrast to results and interpretations of earlier studies, which suggest that <em>Millepora</em> is very rare in the fossil record globally. To understand the reason for this mismatch, we compared the associated scleractinian fauna between fossil reefs with and without <em>Millepora</em> presence. Furthermore, as a differentiation between shallower habitats close to the reef edge and deeper habitats along the reef slope was possible, we were able to investigate habitat preferences. <em>Porites</em> abundances were higher in fossil reefs without <em>Millepora</em>. Based on a comparison with modern communities, this suggests that the exposure to water energy might be a decisive factor for <em>Millepora</em> presence in the fossil reef. Therefore, preservation and consecutive investigation of appropriate fire coral-habitats is a pre-requisite for valid comparisons.</p><p>Another factor for the mismatch between our results and earlier studies might be a difference in diagenetic conditions that allow preservation of hydrozoan skeletons in the fossil record. Preservation of the investigated Egyptian sites is favored by their young geological age and their geographic location in a desert climate, reducing dissolution by aggressive meteoric waters. Furthermore, the extremely high abundance of <em>Millepora</em> in modern Red Sea coral reefs may in part mitigate the lower preservation potential of the hydrozoan skeleton in comparison with that of scleractinian corals.</p>

BENTHIC FORAMINIFERA ASSOCIATED WITH THE ZOOXANTHELLATE CORAL CLADOCORA IN THE PLEISTOCENE OF THE KOS ISLAND (AEGEAN SEA, GREECE): SEA LEVEL CHANGES AND PALAEOENVIRONMENTAL CONDITIONS

A Pleistocene section, cropping out in the northern Kos Island has been selected for study. The main lithology (clayey sands, sandy marls) of the section is interrupted by a prominent Cladocora bank which allows a proper extraction of its faunal contents and identification at species level. The evaluation of benthic foraminiferal assemblages from this bank helps to determine the range of the environmental controls in sedimentation. The foraminiferal assemblage is related to a relatively high supply of organic material and rather strong current intensities in water depth of the coral growth. We suggest that the fossil reef of Cladocora grew in coastal waters characterised by a marked seasonality, with periodical inputs of terrigenous sediments, moderate turbidity and higher temperature than today. Such results, although preliminary, suggest that Cladocora together with benthic foraminifera could be reference species for future work on changing Mediterranean climate and sea level.

Sponges of the Guyana Shelf

Sponges collected on the Guyana Shelf, predominantly in Suriname offshore waters, by Dutch HMS ‘Snellius’ O.C.P.S. 1966, HMS ’Luymes’ O.C.P.S. II 1969, and HMS ‘Luymes’ Guyana Shelf 1970 expeditions are described in this study. Sponges were obtained by trawling, dredging or grabbing on sandy, muddy, shelly, and fossil reef bottoms at 88 stations between 19 and 681 m depth. A total of 351 samples were identified to species level, each consisting of one or more specimens of a given species from each individual station (together comprising 547 individuals and fragments). The collection yielded 119 species together belonging to all sponge classes, but in large majority are Demospongiae. All species are identified to species level, occasionally tentatively, and all are described and illustrated. A new subgenus is proposed, Tedania (Stylotedania) subgen. nov. and a previously synonymized genus, Tylosigma Topsent, 1894 is revived. Thirtysix species were found to be new to science, excluding the first Central West Atlantic record of the genus Halicnemia, not named at the species level because of lack of sufficient material. The new species erected are, in alphabetical order: Amphoriscus ancora sp. nov., Biemna rhabdotylostylota sp. nov., Callyspongia (Callyspongia) scutica sp. nov., Chelonaplysilla americana sp. nov., Cladocroce guyanensis sp. nov., Clathria (Axosuberites) riosae sp. nov., Clathria (Clathria) gomezae sp. nov., Clathria (Microciona) snelliusae sp. nov., Clathria (Thalysias) complanata sp. nov., Clathria (Thalysias) zeai sp. nov., Coelosphaera (Coelosphaera) lissodendoryxoides sp. nov., Craniella crustocorticata sp. nov., Diplastrella spirastrelloides sp. nov., Epipolasis tubulata sp. nov., Erylus rhabdocoronatus sp. nov., Erylus surinamensis sp. nov., Geodia pocillum sp. nov., Geodia sulcata sp. nov., Hemiasterella camelus sp. nov., Hymedesmia (Stylopus) alcoladoi sp. nov., Hymenancora cristoboi sp. nov., Penares sineastra sp. nov., Hymerhabdia kobluki sp. nov., Leucosolenia salpinx sp. nov., Petrosia (Strongylophora) devoogdae sp. nov., Placospongia ruetzleri sp. nov., Pyloderma tropicale sp. nov., Raspailia (Parasyringella) thamnopilosa sp. nov., Raspailia (Raspailia) johnhooperi sp. nov., Sphaerotylus bouryesnaultae sp. nov., Spirastrella erylicola sp. nov., Stelletta vervoorti sp. nov., Suberites crispolobatus sp. nov., Tedania (Stylotedania) folium subgen. nov. sp. nov., Timea tylasterina sp. nov., and Tylosigma ostreicola sp. nov. Two new combinations are proposed: Amphimedon nanaspiculata (Hartman, 1955) comb. nov. and Oceanapia ascidia (Schmidt, 1870) comb. nov. In addition, for two preoccupied combinations, new names, Coelosphaera (Coelosphaera) barbadensis nom. nov. and Hymedesmia (Hymedesmia) rowi nom. nov., are erected. The spatial distribution of the collected specimens over the Guyana Shelf was traced and the results were compared with existing information on bottom conditions. There was a convincing correlation between the location of fossil reefs and other hard substrates such as shell ridges with peaks in the occurrence of species diversity and specimen numbers. Stations made on sand and mud bottoms away from these zones of hard substrates were generally poor in species, but some were found to be rich in individuals of specialized soft bottom dwellers such as Tetilla pentatriaena, Tribrachium schmidtii, Fangophilina submersa, and Oceanapia species. The species composition of the Guyana Shelf was compared with that of neighbouring regions of the Caribbean and from North and East Brazil (Díaz in Miloslavich et al. 2010; Muricy et al. 2011). About 35% of the species encountered are widespread in the Central West Atlantic, occurring both to the north and to the south. Indications that the Guyana Shelf sponge fauna is clearly transitional are southernmost occurrences for Caribbean species (about 30%), and northernmost occurrences of Brazilian species (13%), with a high proportion (25%) of new species, which may be expected to have distributions extending to the Caribbean, to Brazil or both regions.

The landscape structure of the nature reserve “Medobory”

Tovtry is a complex of fossil reef Miocene buildings that creates one of the most picturesque scenery of the surrounding plains of Podillya region. Tovtry zone consists of main ridge (the late Baden barrier reef), isolated Tovtry hills (the late Baden bioherms, located east of the ridge), isolated tovtry (the early Sarmat bioherms, located west of the main ridge), the territories of the former channels, lagoons and passes between certain reef masses, the part of which is occupied with the modern rivers. These geological and geomorphological elements are the basis of the definition of Podillian Tovtry landscapes areas, and their combination is the basis of the individual landscapes. The great contribution to the study of Tovtry landscapes was made by K. Herenchuk (1949, 1979, 1980), who identified the main types of localities and individual landscapes. In addition to his distinguished achievements, the researches done by M. Chyzhov (1963), T. Kovalyshyn and I. Kaplun (1998), P. Shtoyko (2000), K. Moskalyuk (2011) and others could be mentioned. In Tovtry there are four landscapes: Mylno, Zbarazh, Medobory (Krasna) and Tovtry (Kamianets-Podilskyi). Natural Reserve “Medobory” (9 516.7 hectares) is located in the central part of Tovtry, mainly in Medobory landscape. The landscape map of nature reserve, covering the surrounding area, at a scale of 1: 25,000 has been done. Six landscaped areas and more than 70 kinds of tracts have been identified. The largest area is the area of elongated summit plains of main Tovtry ridge rocky hills, covered by beech hornbeam-oak forests on humus-carbonate soils. The territory with the buried reef formations, overlained by loess-like loams, with hornbeam-oak forests on humus-carbonate soils in combination with grey forest soils occupies large area. The area of grouped and isolated side tovtry, covered by rock and meadow-steppe vegetation, shrubs on humus-carbonate soils are fragmentary represented in the natural reserve. Outside the territory of natural reserve, there are areas of the extensive plains with chernozems. They were covered by meadow vegetation in the past and now they are the agricultural lands. Some areas of the reserve are covered by wavy interfluves of Husiatyn and Lanivtsi landscape, which are typical for stratal-tiered landscapes of Podillya. Wavy watersheds, composed of thick strata of loess loam, are mainly covered by hornbeam forests in place of oak on grey forest soils and podzolic chernozem. Along Zbruch and Gnyla the area of narrow river valleys with wide floodplains and low terraces fragments are very common. Floodplain is covered by grass-forb meadows, with alder and osier bed centres on meadow and meadow soils. The regional and local features of the landscape structure of the reserve have been defined. Enough representation of the main types of Tovtry areas, their altitude differentiation (landscape layering) and monolithic areas of Tovtry main ridge are the most important. Key words: Podillian Tovtry, main ridge, side tovtry hills, nature reserve “Medobory”, area of landscape.

The perspectives of geopark creation at Podillian Tovtry region

The possibilities of forming new international category of geoheritage preserving – geopark in Tovtry region has been discussed. The geology-geomorphologic structure of Podillian Tovtry has been described and the inventory of valuable geology-geomorphologic objects – the base of preplanned geopark creation, has been proposed. The list of geotouristic objects and the perspectives for development of educational forms of tourism in the Tovtry has been analyzed. Key words: geology-geomorphologic objects, geoheritage, geopark, Global Geoparks Network, European Geoparks Network, fossil reef, Podillian Tovtry.

Fishes on coral reefs: changing roles over the past 240 million years

Key morphological traits reveal changes in functional morphospace occupation of reef fish assemblages over time. We used measurements of key functional attributes (i.e., lower jaw length and orbit diameter) of 208 fossil fish species from five geological periods to create bivariate plots of functional morphological traits through time. These plots were used to examine possible function and ecological characteristics of fossil reef fish assemblages throughout the Mesozoic and Cenozoic. A previously unknown trend of increasing orbit diameter over time became apparent. The Teleostei are the principal drivers of this change. The Eocene appears to mark a dramatic increase in two previously rare feeding modes in fishes: nocturnal feeding and high-precision benthic feeding. Interestingly, members of the Pycnodontiformes had relatively large eyes since the Triassic and appear to be the ecological precursors of their later teleost counterparts and may have been among the earliest nocturnal feeding fishes. Our results highlight potential changes in the roles of fishes on coral reefs through time.