An Updated Classification of the Recent Crustacea

accommodate some of the former gonodactyloid
taxa (Ahyong, 1997; Ahyong and Harling, 2000;
Cappola and Manning, 1998). Cappola and Manning
(1998) also suggested that a new superfamily
and family (Eurysquilloidoidea, Eurysquilloididae)
should be established to accommodate the former
eurysquillid genus Eurysquilloides. We have followed
the classification suggested by Ahyong and
Harling (2000). According to their scheme, the
families Eurysquillidae and Parasquillidae, formerly
treated as members of the Gonodactyloidea, are
each deserving of superfamily status, and thus they
established the superfamilies Eurysquilloidea and
Parasquilloidea to accommodate them. The Gonodactyloidea
has been reconfigured and now contains
the Alainosquillidae, Hemisquillidae, Gonodactylidae,
Odontodactylidae, Protosquillidae,
Pseudosquillidae, and Takuidae. The family Heterosquillidae
established by Manning (1995) has
been removed, as it was suggested to be a synonym
of Tetrasquillidae (see Ahyong and Harling, 2000).
In the most recent treatment, Ahyong (2001) synonymized
the Harpiosquillidae Manning with the
Squillidae; thus the Harpiosquillidae is not in our
list.
Hof (1998b) recognized two main clades of extant
stomatopods. One clade included most of the
gonodactyloid families but excluded the alainosquillids
and the eurysquillids. The second clade
contained the remaining extant families and indicated
possible affinities between the squilloids and
lysiosquilloids and also between the bathysquilloids
and erythrosquilloids. Hof (1998b) points out that,
although his results are preliminary, the fact that
fossils should be included when at all possible in
any cladistic analysis is clear and obvious from his
work. A cladistic analysis of the hoplocarids that
incorporated Paleozoic taxa was presented by Jenner
et al. (1998), but it did not resolve relationships
within the sole extant order (their Unipeltata). In
the most recent treatment, Ahyong and Harling
(2000) have also suggested that the recent stomatopods
have evolved ‘‘in two broad directions from
the outset,’’ corresponding roughly to the smashing
and spearing types.
SUBCLASS EUMALACOSTRACA
The concept of the Eumalacostraca as a monophyletic
assemblage has not been seriously challenged,
with the exception of the question of whether hoplocarids
belong (see above discussion under Hoplocarida
for arguments as to their inclusion or exclusion).
Our classification is roughly similar to
that of Bowman and Abele (1982) in recognizing
the Eumalacostraca and its constituent groups, although
there have been several significant rearrangements
within and among those groups, as noted
below (see also Richter and Scholtz, in press).
Schram (1984a) reviewed characters that defined
the various eumalacostracan groups recognized at
that time and presented alternatives to more traditional
classifications.
SUPERORDER SYNCARIDA, ORDERS
BATHYNELLACEA AND ANASPIDACEA
Monophyly of the Syncarida appears to be fairly
well accepted (e.g., Schram, 1984b; Richter and
Scholtz, in press). Within the Bathynellacea, we
have removed the family Leptobathynellidae, as
this was synonymized with the Parabathynellidae
by Schminke (1973:56). Schram (1984b) credits
both names (Bathynellidae, Bathynellacea) to
Chappuis (1915), whereas Lopretto and Morrone
(1998) credit the Bathynellidae to Grobben (as did
Bowman and Abele, 1982) and the Bathynellacea
to Chappuis. We have not been able to locate a
paper by Grobben describing bathynellids and so
have followed Schram’s (1984b, 1986) lead, crediting
both taxa to Chappuis (1915). The Anaspidacea
remains unchanged, with four extant families.
Thus, our classification of the Syncarida and its
two orders (Anaspidacea and Bathynellacea) is the
same as that presented by Lopretto and Morrone
(1998), where all known syncarid genera are also
listed, and is essentially the same as the classification
suggested earlier by Schram (1984a:196) based
on a phylogenetic analysis of fossil syncarids (excluding
the entirely fossil order Paleocaridacea).
SUPERORDER PERACARIDA
We continue to recognize the Peracarida, treating it
as a superorder that contains nine orders. This is
mostly in keeping with Bowman and Abele (1982)
and most major treatments since that time (see especially
Hessler and Watling, 1999; Richter and
Scholtz, in press). However, there have been suggestions
made to abandon the Peracarida or at least
significantly revise it (e.g., Dahl, 1983a), and the
relationships among the various peracarid groups
(and of peracarids to other groups of crustaceans)
are very controversial. Schram (1986) advocated
eliminating the Peracarida of earlier workers, feeling
that it united groups that were only superficially
similar. Other workers (e.g., Pires, 1987; Brusca
and Brusca, 1990; Wagner, 1994; Hessler and Watling,
1999; Richter and Scholtz, in press) recognize
the group, but the treatments occasionally differ as
to which orders are included. Hessler and Watling
(1999) review major attempts to phyletically order
the peracarids, including Schram (1986), Watling
(1983), Wills (1997), and Wheeler (1997), all of
which have appeared subsequent to the Bowman
and Abele (1982) classification. There is little agreement
among these various schemes. Mysidaceans in
particular are sometimes treated as one order,
sometimes as the separate orders Lophogastrida
and Mysida within the Peracarida, and sometimes
suggested to fall outside of the Peracarida altogether.
As examples, Watling (1998, 1999b) argues that
mysids should fall outside the Peracarida and that
32 � Contributions in Science, Number 39 Rationale