An Updated Classification of the Recent Crustacea

(1996a–c), Rodríguez (1982, 1986, 1992), and
Sternberg (1997), feel that there is ‘‘strong support
for the idea that the Pseudothelphusidae and Trichodactylidae
each form a natural group,’’ and
Spears and Abele (1999) have suggested that the
pseudothelphusids are deserving of superfamily status.
Christoph Schubart (pers. comm.) also agrees
that the former Potamoidea is polyphyletic, especially
as concerns the South American lineages
(families Pseudothelphusidae and Trichodactylidae).
Our classification is in keeping with most of
the above views.
Thus, excluding the trichodactylids, we recognize
three superfamilies of freshwater crabs: Potamoidea,
Pseudothelphusoidea, and Gercarcinucoidea.
Within the ‘‘potamoid’’ families (superfamily Potamoidea),
the families Sinopotamidae and Isolapotamidae
have been removed, as both are thought
to fall within the limits of the existing Potamidae
(Ng, 1988; Dai et al., 1995; Dai, 1997; Dai and
Türkay, 1997). Sternberg and Cumberlidge (1999)
have recently recognized the monogeneric Platythelphusidae
Colossi, 1920, as a distinct potamoid
family (see also Cumberlidge et al., 1999; Cumberlidge,
1999) and at the same time suggested that
the sister group of the platythelphusids is most likely
the East African family Deckeniidae. The Potamonautidae,
considered to belong to the Potamidae
by Monod (1977, 1980) and Guinot et al. (1997),
is recognized as an independent family following
the works of Ng (1988), Ng and Takeda (1994),
Stewart (1997), Cumberlidge (1999), and Sternberg
et al. (1999).
Thus, within the superfamily Potamoidea, we
recognize only four families here, all of them Old
World groups: Potamidae, Potamonautidae, Deckeniidae,
and Platythelphusidae.
Superfamily Gecarcinucoidea
Only two of the three families originally included
in this superfamily by Bott (1970a, b) are recognized
here: Gecarcinucidae and Parathelphusidae.
The family Sundathelphusidae has been removed,
as that family is now considered a junior synonym
of the Parathelphusidae (Peter Ng, pers. comm; see
also Ng and Sket, 1996; Chia and Ng, 1998). The
family Gecarcinucidae, although recognized as being
artificial as currently defined and in need of revision
(N. Cumberlidge, pers. comm.; and see Cumberlidge,
1987, 1991, 1996a, b, 1999; Cumberlidge
and Sachs, 1991), has been retained for now. Membership
of the family, as currently defined, is likely
to be altered radically in the near future (N. Cumberlidge,
pers. comm.). For example, it is possible
that the Gecarcinucidae will be shown to be restricted
to the Indian subcontinent, Asia, and Australasia
(see Cumberlidge, 1999; Martin and Trautwein,
in press), and it is not represented on the
African continent, despite reports to the contrary
(e.g., Bott, 1970a, b). Evidence for maintaining this
superfamily (Gecarcinucoidea) and for separating
these two families (Gecarcinucidae and Parathelphusidae)
from the four families in the Potamoidea
is weak and controversial. Nevertheless, we are recognizing
the distinctness of the Gecarcinucidae and
Parathelphusidae from the four potamoid families
until further evidence becomes available.
Superfamily Pseudothelphusoidea
Originally established by Bott (1970a, b) to include
two families, Pseudothelphusidae and Potamocarcinidae,
this New World superfamily is now restricted
to a single family. The family Potamocarcinidae
was removed by Rodríguez (1982), and its
species are now included among the Pseudothelphusidae
(see Sternberg et al., 1999). The monophyly
of the family Pseudothelphusidae appears
well established. As noted above, Sternberg et al.
(1999), citing the works of Magalhães and Türkay
(1996a–c), Rodríguez (1982, 1986, 1992), and
Sternberg (1997), feel that there is ‘‘strong support
for the idea that the Pseudothelphusidae and Trichodactylidae
each form a natural group.’’ Spears
and Abele (1999) also have suggested that the pseudothelphusids
may be deserving of superfamily status,
and most workers are in agreement that the
pseudothelphusids are a natural (monophyletic)
group (T. Spears, pers. comm.; C. Schubart, pers.
comm.; Sternberg and Cumberlidge, 1999; Sternberg
et al., 1999). We have retained this superfamily
and its single family Pseudothelphusidae.
Superfamily Cryptochiroidea
Finally in the Heterotremata, the correct name for
the superfamily and family of the coral gall crabs
(Cryptochiroidea and Cryptochiridae, both credited
to Paulson) was recognized by Kropp and Manning
(1985, 1987), who replaced the name Hapalocarcinidae
used previously for this group.
SECTION EUBRACHYURA, SUBSECTION
THORACOTREMATA
Superfamily Pinnotheroidea
C. Schubart (pers. comm.) believes that the Pinnotheridae
‘‘should remain in the Thoracotremata
based on evidence from DNA sequencing.’’ Placement
of the pinnotherids in the Thoracotremata
was also advocated by Števčić (1998) based on
morphological features. Thus, the pinnotherids are
moved to within the Thoracotremata, although the
author of the Thoracotremata does not agree with
this placement (Guinot, pers. comm.) and feels that
they fit better within the Heterotremata. Within the
Pinnotheroidea, it is possible that an additional
family will have to be erected to accommodate the
genera Dissodactylus and Clypeasterophilus, which
differ morphologically (larval characters) and genetically
from other pinnotherids (J. Cuesta, pers.
comm.).
Contributions in Science, Number 39 Rationale 55