JOURNAL OF CRUSTACEAN BIOLOGY, 28(1): 82–127, 2008 REVISION OF PORTUNOIDEA RAFINESQUE, 1815 (DECAPODA: BRACHYURA) WITH EMPHASIS ON THE FOSSIL GENERA AND FAMILIES Hiroaki Karasawa, Carrie E. Schweitzer, and Rodney M. Feldmann (HK) Mizunami Fossil Museum, Yamanouchi, Akeyo, Mizunami, Gifu 509-6132, Japan ([email protected]); (CES, correspondence) Department of Geology, Kent State University Stark Campus, 6000 Frank Ave. NW, North Canton, Ohio 44720, U.S.A. ([email protected]); (RMF) Department of Geology, Kent State University, Kent, Ohio 44242, U.S.A. ([email protected]) ABSTRACT The superfamily Portunoidea including extinct lineages is herein evaluated via cladistic analysis of adult morphological characters and traditional systematics. Nearly every fossil species has been examined via type material, or if this was not possible, through illustrations and original descriptions. The analyses indicate that the superfamily is much more diverse at the family level than has previously been recognized, and three subfamilies, Catoptrinae, Carcininae, and Macropipinae, are herein elevated to family status. One new family, Longusorbiidae; two new genera, Euronectes and Viaophthalmus; and two nomen nova are named herein in addition to the recognition of seven new combinations. The fossil record of each of the resulting families is evaluated and summarized, indicating that the superfamily extends into the Cretaceous but that many of the families are indeed much younger lineages. KEY WORDS: Brachyura, Cretaceous, Neogene, Paleogene, Portunoidea, phylogeny, taxonomy INTRODUCTION proposing a phylogenetic hypothesis, the results of these Portunoidea embraces a diverse array of taxa known from studies are that the geological history of the group is ignored a broad spectrum of marine and non-marine habitats. Martin and fossil taxa that are demonstrated to be members of the and Davis (2001) included three extant families: Geryonidae group are simply ‘‘inserted’’ into the classification. One of Colosi, 1923; Portunidae Rafinesque, 1815; and Trichodac- the consequences of this approach is that generic taxa tylidae H. Milne Edwards, 1853. The genus, Sylviocarcinus known from the fossil record are placed within families on H. Milne Edwards, 1853, within the latter family is the basis of gross morphological similarity which can then restricted to non-marine habitats. To this list, the extinct foster misinterpretations of the geological history of taxa. marine Carcineretidae Beurlen, 1930, has typically been Recognizing the great breadth of taxa within Portunoidea; assigned to the superfamily (Glaessner, 1969). Other the long geological history of some of its members, authors, discussed below, have proposed other family-level extending into the Cretaceous; and the problems of clas- arrangements. A compilation as a part of a broad study that sification of both extant and extinct forms; the present study is underway to develop a phylogeny of the decapod has several objectives. Utilizing morphological data from crustaceans based upon morphological, molecular, and a broad array of extinct and extant genera, it is the primary paleontological evidence has resulted in the identification purpose of this study to develop a testable hypothesis to of approximately 88 genus-level taxa within the super- elucidate the phylogeny of Portunoidea. In so doing, a broad family, most assigned to Portunidae. Recognition of this spectrum of characters is employed, some of which are vast number of genera documents the wide range of rarely observable on fossil crabs, but all of which have been variation within the superfamily. In order to assure that utilized in classification schemes of extant forms. This these taxa are arrayed phylogenetically, it is necessary to re- approach permits framing a second hypothesis, that the examine the current classification scheme and test the phylogenetic scheme derived from study of extinct and homogeneity of the family groupings. An initial study of extant taxa will not differ significantly from one based extinct genera within Carcineretidae (Schweitzer et al., solely upon extant forms. Stated another way, we propose to 2007) resulted in the reduction of genera that could test whether or not the insertion of data from fossil forms, legitimately be assigned to the family from seven to three; with all the attendant problems of missing information, will the other genera were either assigned to other portunoid significantly perturb the resulting phylogenetic topology. families or were assigned to other superfamilies. This study Finally, having identified a reasonable phylogenetic array, clearly documented the need for a re-evaluation of the entire we intend to propose a systematic framework that embraces superfamily in a phylogenetic context. monophyletic groups based upon morphological analyses, In addition to the recognition that Portunoidea is an define a family and subfamily structure that reflects this extremely diverse group, it was also abundantly clear that arrangement, reassign generic-level taxa to their most the current classification scheme(s) are based almost solely appropriate family-level position, and refine the diagnoses on criteria derived from study of extant organisms. of the resultant families and subfamilies. Although this approach can be justified on the basis of The summation of the results of our work is that a very availability of material and the wide range of morphological stable tree topology emerged, one that was not substantially criteria that can be utilized in erecting a classification or perturbed by the addition of data from extinct taxa. Further, 82 KARASAWA ET AL.: REVISION OF PORTUNOIDEA 83 the morphology-based phylogenetic analysis resulted in an A. Milne-Edwards and divided the group into two sections, array of monophyletic groups that rather strongly supported Podophthalmidae and Portunidae with the subfamilies many aspects of existing systematic arrangements. Thus, the Lupinae, Thalamitinae, Carcininae, and Caphyrinae. Alcock present results offer a phylogenetic arrangement that can (1899) placed four subfamilies, Carcininae, Portuninae, be compared and contrasted to phylogenies derived from Caphyrinae, and Lupinae under Portunidae. Additionally, molecular studies. In addition, nearly every fossil species in his classification, each subfamily was subdivided into has been verified as to its generic placement either by ex- several alliances. amination of illustrations and descriptions in the literature, In the 20th century, Borradaile (1907) recognized eight or examination of type or referred material where possible. subfamilies: Carcinidinae, Portumninae, Catoptrinae, Car- Thus, this work represents the most comprehensive evalua- upinae, Portuninae, Caphyrinae, Thalamitinae, and Podoph- tion yet undertaken of the fossil record of Portunoidea. thalminae. Klunzinger (1913) divided Portunidae into eight subfamilies: Carcininae, Pirimelinae, Portuninae, Carupinae, Lupinae, Thalamitinae, Caphirinae [sic], and Podophthal- HISTORY OF CLASSIFICATION minae. Pirimelinae Alcock, 1899 was originally included Beurlen (1930) first recognized the superfamily (as his within Cancridae (Alcock, 1899), and subsequently Bouvier tribus) Portunoidea containing two families, Carcineretidae (1940) gave it full family status. Pirimelidae is usually Beurlen, 1930, and Portunidae Rafinesque, 1815, sensu treated as a family of Cancroidea (Guinot, 1978; Bowman Dana, 1851. Prior to Beurlen’s work, Ortmann (1893) es- and Abele, 1982; Martin and Davis, 2001). In a recent tablished his section Portuninea as the present superfamily- molecular work, Schubart and Reuschel (2005) suggested level name and he placed seven of his new families under that Pirimelidae should be assigned to Portunoidea. Beurlen the section: Platyonychidae, Polybiidae, Carupidae, Portu- (1930) included three extant subfamilies, Carcininae, nidae, Thalamitidae, Lissocarcinidae, and Podophthalmidae. Portuninae, and Lupinae, and one extinct family, Psammo- Until the work presented herein, these families had been carcininae Beurlen, 1930, within Portunidae. recognized as subfamilies of Portunidae. Subsequent to Sakai (1939) recognized six subfamilies under Portuni- Beurlen’s work (1930), most neontologists included only dae: Carcininae, Catoptrinae, Portuninae, Caphyrinae, one family, Portunidae, within Portunoidea (Sakai, 1976), Lupinae, and Podophthalminae. Balss (1957) divided the and paleontologists added the extinct family Carcineretidae families into nine subfamilies: Carcineretinae, Psammocar- to the superfamily (Glaessner, 1969; Guinot, 1978). cininae, Carcininae, Catoptrinae, Carupinae, Portuninae, Manning and Holthuis (1981) and Rice (1980) suggested Neptuninae (his replacement name of Lupinae), Caphyrinae, that Geryonidae had close affinities with Portunidae, and and Podophthalminae. The classification of Portunidae pro- subsequently, Bowman and Abele (1982) placed Geryoni- posed by Sakai (1939) was largely accepted by subsequent dae within Portunoidea. Since Rodrı´guez (1992) demon- workers (Edmondson, 1954; Stephenson and Campbell, strated that the freshwater crab family Trichodactylidae H. 1960; Stephenson, 1972; Sakai, 1976). After that, Stephen- Milne Edwards, 1853, was the sister to Portunidae based upon a cladistic analysis, Von Sternberg et al. (1999), Von son and Campbell (1960) proposed the replacement name, Sternberg and Cumberlidge (2001), and Martin and Davis Macropipinae Stephenson and Campbell, 1960, for the cur- (2001) placed Trichodactylidae within Portunoidea.