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drill hole,
Asterichnus
to describe the stellate shape of a trace, and so on. Unfor-
tunately, as Frey recognized in private, this has led to stylistically awkward but
unavoidable phrases like “ichnogenus
Teichichnus
”, and perhaps it is time to
become more creative.
One cannot simply put two Latin words together to make a new Latin word.
In general, the first word should be reduced to its root, that is, the part without
the ending. If the first root ends in a consonant and the second begins in a
consonant, usually a connecting vowel -
i
- is inserted, for example,
Arenicolites,
because few consonant clusters are allowed in Latin, unlike German, for
instance. The usual connecting vowel for Greek roots is -
o
-, for example,
Asterosoma, Diplocraterion,
and
Ophiomorpha
.Itisd
´
class
´
to mix unlati-
nized Greek and Latin in the same word, though it is permissible to mix latinized
Greek with Latin, for example,
Stelloglyphus, Ancorichnus
.
7.4 Diagnosis and Description
The naming of new trace fossils, to paraphrase T. S. Eliot, is a difficult matter.
It may seem trivial to mention this, but the first step is to observe the trace fos-
sils. The initial description may be followed by a tentative identification, which
may suggest further morphological details to seek out. In practice, description is
partly informed by the process of identification, and it is often necessary to
return to an outcrop or a museum drawer to gain new information.
How can one find out if the new trace fossil is really new? There is no one
source that includes descriptions of all ichnotaxa; identification may require
access to a large library. The most extensive key for invertebrate ichnogenera
is that of
Knaust (2012)
. Brief descriptions and illustrations of many ichnogenera
are available in the second edition of the “Trace Fossils and Problematica” part of
the
Treatise on Invertebrate Paleontology,
a posthumous work by
H¨ntzschel
(1975)
. This is the closest we have to a compendium of trace fossils thought
to be of invertebrate origin; every such ichnogenus known at that time was
listed alphabetically. However, it was never intended as an identification man-
ual. Other, more specialized works that may be of use in identification are
summarized briefly in
Table 3
.
The
Treatise
is a very useful work, but the researcher should be aware of some
additional problems with using it as a source. H¨ntzschel's research was
incomplete at the time of his death (
Teichert, 1975:
vi), and some well-defined
ichnogenera were relegated to a waste pile entitled “Unrecognized and Unrecog-
nizable Genera” from which a few good names (e.g.,
Ptychoplasma
)havesince
been salvaged, usually after investigation of type specimens. Another problem
with this work is the fact that many trace fossils were already described in other
parts of the
Treatise
and the editor evidently did not want to duplicate them under
“Trace Fossils”. Many of the genera listed as medusae (
Harrington and Moore,
1956
) or worms (
Howell, 1962
) are trace fossils. Moreover, some genera of fossil
“boring animals” are now considered as ichnogenera of fossil borings, a
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