Coded Taxonomic Description
The Order Symphypleona Börner, 1901 shows some ambiguity in current
morphological methods, particularly when describing the head and body
chaetotaxy (Betsch 1997, Betsch & Waller 1994, Bretfeld 1990, 1999,
Christiansen & Bellinger 1998). The Order is composed by springtails
with globular body shape, as result of modification and fusion of
thoracic and abdominal segments I-IV, this condition hinders the direct
assignment of segments identity.
An approach that can reduce the ambiguity of the taxonomic descriptions,
is the description of body parts into coded morphological units,
straightforwardly representing the actual body segments and appendicular
whorls (Hopkin 1997, Jura et al., 1987, Nayrolles 1988, 1990a, 1990b,
1991, Tomizuka & Machida 2015), in such a way that any species can be
compared from the coded data base. This is in replacement to the
traditional descriptive text, many times with ambiguous terminology, and
often applying different and not directly comparable chaetotaxic
systems. The coded notation method would lead to a more comprehensive
analysis of the chaetotaxy, as well as a direct availability of the data
for comparative studies. Furthermore, a coded description can easily be
amended, molecular data can be added in the character list and matrix,
and new complementary morphological features can be inserted as new
information is available.
The qualitative description of the shape and size of the different
chaeta is also subject to a great deal of ambiguity and poor definition,
the adjectives are not standard and the very definition of what is a
macro, meso or microchaeta is not always clear. Therefore, a bank of
shapes with high quality images is imperative to discard all the
subjective descriptions. There are several chaetae banks published for
different groups of Collembola, including some with precise line
drawings(Betsch 1980, Christiansen 1966, Deharveng 1983, Nayrolles
1991), and some with SEM photography(Cipola et al., 2020, de Lima et
al., 2022, Lukić et al., 2010, Zeppelini et al., 2022, Zhang &
Deharveng 2015), it is a matter of time to have a fully reliable chaetal
shapes collection, so a specific chaeta can be addressed directly by its
reference in the bank, in the coded description.
A standard, fully coded method for species description may be an
improvement to the traditional descriptive text, it may allow to use
machine learning and high-quality imaging to enhance the efficiency of
species descriptions and diversity recognition, offering a powerful tool
to understanding of global processes, and face the diversity decline.