In providing the full name of a trace fossil, the ichnogenus is followed by the
ID: 803138 • Letter: I
Question
In providing the full name of a trace fossil, the ichnogenus is followed by the ichnospecies (e.g. Skolithos linearis). Note that both terms in the name are italicized and only the ichnogenus is capitalized. In this lab, we will be dealing with ichnogenus names only (e.g. Skolithos). The identification of a trace fossil is based on its description. The following must be noted when a trace fossil is described: The position of the trace fossil relative to the sediment/fluid interface. For this purpose, terminology developed for the preservation or toponomic classification of trace fossils is used (Figure 1). The terminology developed by Seilacher (1964) (full relief, semirelief, epi and hyporelief) is used in this lab. Trace fossils completely enclosed within a bed are called full reliefs whereas those at the contact between beds are called semireliefs. Semireliefs are further subdivided into epireliefs (those that occur on the upper surface of a bed) and hyporeliefs (those that occur on a lower surface of a bed; just as in sedimentary structures). Note whether or not epireliefs and hyporeliefs are concave or convex.Explanation / Answer
Ichno genus is identified only from trace fossils, the traces such as footprints, coprolites or nests and other biomarks.
Rhizocorallium is one of the oldest known trace fossils distributed in the age Phanerozoic period. Commonly represents spreiten burrows obliquely to the bedding plane. Rhizocorallium jenense and Rhizocorallium commune are the only identified ichnospecies of Rhizocorallium. Palaeozoic and Mesozoic Rhizocorallium commune are restricted to the Cruziana ichnofacies of shallow-marine environments, while in Cenozoic time similar forms are also found in deep-marine deposits. Mainly these are epireliefs sometimes these represents full reliefs. These ichnofossils indicated the palaeoenvironments. Rhizocorallium is used to describe sequence tratigraphical surfaces and fluctuations in salinity and also oxygen.