Filamentous micro-organisms in Upper Cretaceous amber (Martigues, France)

Filamentous micro-organisms, inorganic inclusions and pseudo-fossils in the Miocene amber from Totolapa (Chiapas, Mexico): taphonomy and systematics

“…Bacterial and fungal contents of these microfloras is exemplified by Mid-Cretaceous, Upper Cretaceous, and Eocene ambers, and by modern resin. Studied Mid-Cretaceous colonizers of resins were mainly cyanobacteria and sheathed bacteria (Breton, 2007;Girard, 2010, Girard et al, 2009a; Upper Cretaceous and Eocene were actinomycetes (Breton, 2010;, Breton et al, 2013Saint Martin et al, 2012;, whilst modern resins are largely settled by fungi (Breton, 2011;. The Miocene amber of Totolapa provides us insight on Miocene settlers, until now an unexplored period.…”

“…Large areas of the surface of the exudate can be colonized, either by a network of filaments parallel to the surface, or growing centripetally (filamentous bacteria and fungi) or by a turf of clumps with a centripetal growth (some actinomycetes) (Breton, 2011(Breton, , 2012. The early colonization of fossil resin exudates by such filamentous micro-organisms has also been described, for instance in Cretaceous or Eocene amber (Girard et al, 2009a,d;Breton, 2010Breton, , 2011Girard, 2010;Saint Martin et al, 2012;Breton, 2012;Saint Martin et al, 2013;Breton et al, 2013). Among the taxa described herein, Melanothrix mexicana, Thermomonosporopsis chiapasensis, the actinomycete gen. A sp.…”

“…Palaeocolteronema cenomanensis has dichotomic branching, its sheath is hyaline, devoid of granulations and of a smaller diameter; it can bear hormogonias. All three taxa, as well as other unnamed sheathed filaments are to be found in French and Spanish Cretaceous ambers (Breton and Tostain, 2005;Girard, 2010;Saint Martin et al, 2012;Breton, 2012;Breton et al, 2013;Saint Martin et al, 2013).…”

“…Paleontologists used to pay more attention to macrofauna preserved in amber, especially insects, than to micro-organisms (see for instance Poinar, 1992Poinar, , 1994 although pollen, fungi mycelia, algal filaments, bacteria or spores have been known for a long time (Göppert and Berendt, 1845;Göppert and Menge, 1883;Galippe, 1920;Blunck, 1929). The excellent preservation of micro-organisms has allowed, more recently, descriptive and analytic studies of this type of material (Waggoner and Poinar, 1992;Poinar et al, 1993;Waggoner, 1993Waggoner, , 1994aWaggoner, , b, 1996Kohring, 1995;Waggoner, 1996, Breton et al, 1999Schmidt et al, 2004;Breton and Tostain, 2005;Schmidt and Schäfer, 2005;Schmidt, 2006;Schmidt et al, 2006;Breton, 2007;Schmidt and Dilcher, 2007;Schmidt et al, , 2008Girard, 2009;Girard et al, 2009a, b, c, d;Breton, 2010;Girard, 2010;Breton,2012;Girard, 2012;Saint Martin et al, 2012;Breton et al, 2013;Saint Martin et al, 2013). The latest studies have shown that many of these micro-organisms were resinicolous organisms that grew in resin, and soon after its production, colonized the exudate and embedded themselves within resin in a quite different way than trapped micro-organisms (pollen for instance) or macro-organisms (insects for instance).…”

“…Schmidt and Schäfer, 2005;Girard et al, 2009a), Upper Cretaceous (e.g. Saint Martin et al, 2012Martin et al, , 2013, and Eocene amber (e.g. Breton, 2012) and in modern resins (e.g.…”