| Biomarker | Biological and/or environmental interpretation | References |
|---|
| Hopanoids |
|---|
| C30-hopanes | diverse bacterial lineages, few eukaryotic species (e.g. some cryptogams, ferns, mosses, lichens, filamentous fungi, protists) | Rohmer et al., 1984 |
| extended C31 to C35 hopanes (a.k.a. homohopanes) | diagnostic for Bacteria, biosynthesis appears to be restricted to lineages that are not strictly anaerobic (with a possible exception (Thiel et al., 2003) | Ourisson and Albrecht, 1992, Rohmer et al., 1984 |
| extended C32 to C36 2a-methylhopanes | diagnostic for cyanobacteria and prochlorophytes | Bisseret et al., 1985, Summons et al., 1999 |
| extended C32 to C36 3b-methylhopanes | diagnostic for some microaerophilic proteobacteria (certain methylotrophs, methanotrophs, acetic acid bacteria) | Zundel and Rohmer, 1985a, Zundel and Rohmer, 1985b, Zundel and Rohmer, 1985c, Summons and Jahnke, 1992 |
| 28,30-dinorhopane, 25,28,30-trinorhopane (TNH) | often prominent in sediments from euxinic environments | Grantham et al., 1980, Peters and Moldowan, 1993 |
| Steroids |
|---|
| 24-norcholestane (C26) | possible diatom origin, high concentrations relative to 27-norcholestane indicate Cretaceous or younger crude oil | Holba et al., 1998a, Holba et al., 1998b |
| Cholestane | in aquatic sources probably almost exclusively derived from diverse eukaryotes | Volkman, 2003 |
| in organic matter from terrestrial sources (e.g. paleosols) input from soil bacteria of the order Mxyococcales conceivable | Bode et al., 2003, Kohl et al., 1983 |
| Ergostane, stigmastane | exclusively eukaryotic, but usually no distinct sources discernible | Volkman, 2003 |
| 24-n-propylcholestane | pelagophyte algae, a biomarker for marine conditions with few exceptions | Moldowan et al., 1990 |
| 24-isopropylcholestane | sponges and possibly the sponge-related stromatoporoids | McCaffrey et al., 1994b |
| 2- and 3-alkylsteranes | ubiquitous in bitumens of all ages, possibly heterotrophic alteration products of sedimentary steroids | Summons and Capon, 1991 |
| 4-Methycholestane and 4,4-dimethylcholestane | diverse eukaryotic sources, high concentrations likely indicate a dinoflagellates origin | Summons et al., 1994a |
| if strongly depleted in 13C indicative for methylotrophic bacteria (Methylococcaceae) | Volkman, 2003 |
| 4-methylergostane, 4-methylstigmastane | diverse eukaryotic sources, high concentrations likely indicate a dinoflagellate origin | Volkman, 2003 |
| Dinosterane | in the Mesozoic and Cenozoic specific for dinoflagellates (with possible minor diatom contribution), in Paleozoic and Neoproterozoic samples probably derived from protodinoflagellates | Moldowan and Talyzina, 1998, Robinson et al., 1984, Volkman et al., 1993 |
