Microendoliths of the Shallow Euphotic Zone in open and shaded habitats at 30°N – Eilat, Israel – paleoecological implications

Abstract

This study examines microendolithic community patterns in experimental carbonate blocks in shallow waters between 0 m and 30 m adjacent to Eilat, Israel. We set up two different habitats per depth: one in full light and one shaded. After 6 months of exposure we observed 23 species of which five are unknown to science and herein described as forms. Differences in community patterns between open and shaded habitats were clearly visible at 0 m, indistinct between 6 m and 15 m and indiscernible at 30 m. Three modern producers of key ichnotaxa were confirmed in our experiments within their paleobathymetrical range: Hyella balani (Fascichnus acinosus), Conchocelis (Palaeoconchocelis starmachii), and Ostreobium quekettii (Ichnoreticulina elegans). For Fascichnus dactylus we found six possible producers. We dismiss Scolecia filosa, Eurygonum nodosum and Rhopalia catenata as potential key ichnotaxa because of the broad bathymetrical range of their producers.

New insights into Lithocodium aggregatum Elliott 1956 and Bacinella irregularis Radoičić 1959 (Late Jurassic–Lower Cretaceous): two ulvophycean green algae (?Order Ulotrichales) with a heteromorphic life cycle (epilithic/euendolithic)

“…The scarce literature dealing with this topic, however, points to increased nutrient concentrations, which could have stimulated blooms of the chlorophyte Lithocodium aggregatum Elliott. Furthermore, the associated calcimicrobial paleocommunity and the micro-/macroendolithic community patterns should show diVerences depending on the water depth where these crusts were formed, as observed in modern taxa (e.g., GolubiT et al 1975;Le Campion-Alsumard 1979;Budd and Perkins 1980;Günther 1990;Glaub 1994;Perry 1998;Glaub 1994;Radtke and GolubiT 2005;Gektidis et al 2006;Glaub et al 2007;Heindel et al 2008). Concerning the Lower Aptian Lithocodium-crusts in the western Maestrat Basin, the uncertainty of the taxonomic calcimicrobial and ichnotaxonomical composition does not allow a clear conclusion concerning the paleodepth.…”

Erratum to: New insights into Lithocodium aggregatum Elliott 1956 and Bacinella irregularis Radoičić 1959 (Late Jurassic–Lower Cretaceous): two ulvophycean green algae (?Order Ulotrichales) with a heteromorphic life cycle (epilithic/euendolithic)

“…The scarce literature dealing with this topic, however, points to increased nutrient concentrations, which could have stimulated blooms of the chlorophyte Lithocodium aggregatum Elliott. Furthermore, the associated calcimicrobial paleocommunity and the micro-/macroendolithic community patterns should show diVerences depending on the water depth where these crusts were formed, as observed in modern taxa (e.g., GolubiT et al 1975;Le Campion-Alsumard 1979;Budd and Perkins 1980;Günther 1990;Glaub 1994;Perry 1998;Glaub 1994;Radtke and GolubiT 2005;Gektidis et al 2006;Glaub et al 2007;Heindel et al 2008). Concerning the Lower Aptian Lithocodiumcrusts in the western Maestrat Basin, the uncertainty of the taxonomic calcimicrobial and ichnotaxonomical composition does not allow a clear conclusion concerning the paleodepth.…”

Earliest diagenesis in scleractinian coral skeletons: implications for palaeoclimate-sensitive geochemical archives

“…They occur in all parts of the coral skeleton, including the most recently deposited areas that are enveloped by living coral polyps, but are most concentrated in distinctive green to grey stained bands. Resin casts suggest that several microborers coexist, including Ostreobium quekettii, endolithic fungi, and the cyanobacterium Mastigocoleus testarum (Le Campion-Alsumard et al 1995a; Gektidis et al 2006). The majority of the microborings can be attributed to O. quekettii, which occurs in high densities in some samples.…”

“…f Thin-section photomicrograph of Porites lobata (03-10-75) at the growth tip of a septum with fungal hyphae having bored to with a few micrometer of the growth surface. The hypha displays a typical bulbous terminal swelling (e.g., Gektidis et al 2006) ᭣ ᭤ Fig. 10 Scanning electron microscope images and thin section photomicrograph of fungal protuberances within the coral skeleton.…”

“…Microbial borers identiWed from resin casts are typical of shallow marine carbonate environments (e.g., Holmes et al 2000;Vogel et al 2000;Perry and Macdonald 2002;Golubic et al 2005;Gektidis et al 2006). The green alga Ostreobium is ubiquitous in skeletons of live corals and is generally associated with Plectonema terebrans (Lukas 1974).…”