An Updated Classification of the Recent Crustacea

ored to credit the person or persons who first used
that name in its new (higher) context when this information
was known to us. In other instances
where we were unsure or where we could not personally
check the original literature, we have employed
the oldest known name and date, more in
keeping with the suggestion by Holthuis (pers.
comm.) to extend ICZN 50.3.1 to higher categories.
Thus, the present classification, like many others
before it, is something of an unfortunate mix of
‘‘rules’’ used to credit authors and dates with the
establishment of taxa. M. Grygier (pers. comm.) informs
us that the above discussion is slightly misinformed
in that the term ‘‘family group’’ explicitly
includes superfamilies (ICZN article 35.1), such
that the real difficulty should be only at the level of
suborder (or any level above that of superfamily).
One of the specific suggestions we received from
several workers was a plea to credit Latreille (1803)
for a large number of higher level crustacean taxa
(we had used the date 1802 in earlier editions of
the classification). These taxa include Ostracoda,
Malacostraca, Gammaridae (and thus Gammaridea),
Oniscidea (and thus Oniscoidea), Astacidea
(and thus Astacoidea), Palinura, Paguroidea, Brachyura,
Squilloidea, and many more. Our choice of
1802 instead of 1803 is based on the following information
quoted from a letter we received from L.
Holthuis (pers. comm., 13 July 1998) referring to
an earlier draft of our classification:
Some of Latreille’s names proposed in his Histoire naturelle
générale et particulière des Crustacés et des Insectes,
vol. 3 . . . have been cited with the year 1802
. . . others have the year 1803. The year of publication
of vol. 3 of Latreille’s work was studied by the best
authority on Latreille, namely C. Dupuis, who in 1975
(Bulletin of Zoological Nomenclature, 32: 4) stated
that this vol. 3 was published after April 1802 and before
6 November 1802, thus definitely in 1802. Therefore
all the author’s names ‘Latreille, 1803’ should be
changed to ‘Latreille, 1802.’
Similarly, unless we had fairly convincing evidence
to the contrary, in those cases where we were
faced with a choice of different dates (which usually,
although not always, meant also different authors,
such as White, 1850 vs. Dana, 1853 vs. Harger,
1879, all suggested to us by different workers
as the correct author/date of the isopod family Limnoriidae)
for the establishment of a taxon, we went
with the earliest date. In this particular example, at
least, it proved the correct choice, as White (1850)
is indeed the author of the family Limnoriidae (G.
Poore, pers. comm.).
Finally, we wish to caution readers that we have
not been able to research each name to the degree
that we would have liked, and we have depended
instead upon the many contributors (not all of
whom were in agreement). Consequently, we would
advise any user of this (or any other) classification
to take the time necessary to research carefully the
history of each taxonomic name for his- or herself,
which, because of the sheer number of names involved
in this project, we simply were not able to
do.
CLADISTICS AND CLASSIFICATION OF THE
CRUSTACEA
Ideally, a classification should accurately reflect the
phylogenetic history of the group. We are very
much in favor of following rigorous cladistic analyses
wherever possible, and some of the newly proposed
classification reflects phylogenetic hypotheses
based on cladistic analysis of morphological and/or
molecular data. However, saying that we favor
classifications based on rigorous cladistic methods
is not the same as saying that any cladistic analysis
is more correct than every preceding hypothesis of
crustacean phylogeny. We wish to state this more
clearly so that there can be no mistaking our meaning:
A phylogeny is not correct simply because it
was generated using cladistics. This somewhat obvious
point is quite often overlooked. The advantage
that cladistics imparts is the objective use of
synapomorphies to define clades. Cladistics is a
powerful tool, and, like all such tools, it must be
wielded carefully. And, as with any other tool, there
is never any guarantee that the result is ‘‘correct.’’
We received numerous suggestions that we employ
a ‘‘more cladistic’’ approach to our new classification.
For many crustacean assemblages, there have
been no proposed phylogenies, cladistic or otherwise.
For other groups, although cladistic methods
may have been used, there are no published or accessible
data for confirmation of the results, and/or
the proposed phylogenies are in stark contrast with
large literatures on fossil, morphological, developmental,
or molecular studies of these taxa, making
them, at least to us, suspect. Two taxa that demonstrate
this problem are the Maxillopoda and the
Decapoda, for which some of the most vocal proponents
of cladistic approaches gave us quite different
suggestions for the classification, all supposedly
based on rigorous cladistic analyses of ‘‘good’’
data. Similar frustration concerning recent attempts
to cladistically analyze fossil arthropods is expressed
by Fryer (1999c). More troubling still is
that there are other cladistic analyses of which we
are aware, and that appear to be based on solid
evidence, that we could not follow completely because
to do so would have orphaned large numbers
of families. For example, we do not doubt the revelation
by Cunningham et al. (1992) that king crabs
of the family Lithodidae are actually nested within
one clade of hermit crabs (but see McLaughlin and
Lemaitre, 1997, 2000, for a dissenting opinion).
But there are other clades of hermits and other species
of lithodids that were not part of this study,
and we hesitated to make sweeping changes before
all evidence is in. Another example concerns dromiacean
crabs, traditionally placed among the lower
Brachyura but whose larvae appear distinctly anomuran.
The molecular analysis of Spears et al.
(1992) grouped at least one dromiid with the An-
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