An update of phylogenetic reconstructions, classification and morphological characters of extant Portunoidea Rafinesque, 1815 (Decapoda, Brachyura, Heterotremata), with a discussion of their relevance to fossil material

Abstract

An update of phylogenetic reconstructions, classification and morphological characters of extant Portunoidea Rafinesque, 1815 (Decapoda, Brachyura, Heterotremata), with a discussion of their relevance to fossil material Posodobitev filogenetske rekonstrukcije, klasifikacije in morfoloških znakov recentnih rakovic Portunoidea Rafinesque, 1815 (Decapoda, Brachyura, Heterotremata) z razpravo o njihovi pomembnosti za fosilni material Abstract The classification of extant Portunoidea has recently been significantly rearranged on the basis of morphological revision and molecular phylogenetic reconstructions. There is an urgent need to reach compatibility of fossil portunoid taxa with this new classification. Furthermore, several genera with a variety of both Recent and fossil representatives, e.g., the genus Portunus (sensu lato), have been split into other genera, but referring fossil species to these is still problematic. In order to facilitate the development of an integrated system that includes both extant and extinct portunoid taxa, a review of recent results regarding the phylogeny of portunoid crabs, an update of their extant taxa classification and a reappraisal of important morphological characters that can be used for assessment of both fossil and contemporary species are presented. A new subfamily, Parathranitiinae, is established within the Carcinidae and within the Portunidae, another new subfamily, Achelouinae, is introduced. Integration of palaeontological data and the evolutionary classification of extant Portunoidea is a challenging task that requires further development of comparative morphological, ecological and molecular genetic studies of modern species. Izvleček Razvrstitev recentnih portunoidnih rakovic je bila v zadnjem času bistveno preurejena na podlagi revizije morfologije in molekularnih filogenetskih rekonstrukcij. Potrebno je zagotoviti združljivost fosilnih portunoidnih taksonov z novo klasifikacijo. Več rodov z živečimi in fosilnimi predstavniki, na primer rod Portunus (sensu lato), je bilo razdeljenih na druge rodove, zato je uvrščanje fosilnih vrst vanje problematično. Da bi zagotovili razvoj integriranega sistema, ki vključuje obstoječe in izumrle portunoidne taksone, je potreben pregled novih spoznanj o filogeniji portunoidnih rakov, posodobitev njihove obstoječe klasifikacije in ponovna ocena pomembnih morfoloških znakov, ki jih je mogoče uporabiti za določanje fosilnih in recentnih vrst. V okviru družine Carcinidae je ustanovljena nova poddružina Parathranitiinae, znotraj Portunidae pa nova poddružina, Achelouinae. Vključevanje paleontološkega materiala in evolucijske klasifikacije recentnih portunoidnih rakovic je zahtevna naloga, ki zahteva nadaljnji razvoj primerjalno morfoloških, ekoloških in molekularno genetskih raziskav obstoječih vrst.

Libystes A. Milne-Edwards, 1867 (Crustacea: Decapoda: Portunidae): re-establishment of L. nitidus A. Milne-Edwards, 1867, reinstatement of L. alphonsi Alcock, 1900 and a description of a new species from the Red Sea

“…Libystes A. Milne-Edwards, 1867: 285;Nobili, 1906: 297;Alcock, 1900: 304-305;Tesch, 1918: 177-178;Balss, 1922: 133;Sakai T., 1939: 372;1976: 324;Stephenson, Campbell, 1960: 85-86;Crosnier, 1962: 13-14;Serène, 1966: 992;Guinot, 1967: 253;Stephenson, 1972: 29;Dai et al 1986: 181;Dai, Yang, 1991: 200;Apel, Spiridonov, 1998: 174;Ng et al, 2008: 217 (list); Naderloo, 2017: 189;Spiridonov, 2020: 140. Lybistes [sic] Cano, 1889bSakai T., 1939: 371 (key).…”

“…Libystes A. Milne-Edwards, 1867 is considered to be a strongly morphologically modified portunid crab genus [Schubart, Reuschel, 2009;Spiridonov et al, 2014;Evans, 2018;Spiridonov, 2020] because these crabs are poorly adapted for or incapable of swimming [Steudel, 1998]. Currently, six Libystes species are recognized [Ng et al, 2008]: L. edwardsi Alcock, 1900, L. lepidus Miyake et Takeda, 1970, L. nitidus A. Milne-Edwards, 1867, L. paucidentatus Stephenson et Campbell, 1960, L. vietnamensis Tien, 1969, and L. villosus Rathbun, 1924.…”

A revision of the swimming crabs of the Indo – West Pacific Xiphonectes hastatoides (Fabricius, 1798) species complex (Crustacea: Brachyura: Portunidae)

“…Even with the substantial systematic revisions proposed by Schubart & Reuschel [2009], Spiridonov et al [2014], Evans [2018] and Spiridonov [2020], the Portunoidea is still considered a heterogeneous superfamily. In particular, the subgeneric system widely used for Portunus Weber, 1795, has been questioned.…”

New insights into the evolution of portunoid swimming crabs (Portunoidea, Heterotremeta, Brachyura) and the brachyuran axial skeleton

“…To answer this question, a robust phylogenetic hypothesis is necessary, which to date, has not been achieved. Previous phylogenetic analyses of Portunoidea are still controversially, at least in parts (Karasawa et al 2008, Schubart & Reuschel 2009, Spiridonov et al 2014, Evans 2018, Spiridonov 2020). In the present study, a new phylogenetic hypothesis is deduced by combing available gene sequences (with some new data of species in which to date, sequences were missing) with new morphological data of inner anatomy, together with newly conceptualized characters of external structures, which for the most part is based on Karasawa et al (2008).…”

“…In the present study, a new phylogenetic hypothesis is deduced by combing available gene sequences (with some new data of species in which to date, sequences were missing) with new morphological data of inner anatomy, together with newly conceptualized characters of external structures, which for the most part is based on Karasawa et al (2008). Statements by Evans (2018) and Spiridonov (2020) is also considered in our character conceptualization. To understand the evolution of morphological traits, the ancestral states of characters are reconstructed based on parsimony (Swofford & Maddison 1996, Rieppel 1999, Schuh 2000.…”