Essai d’analyse critique des principales hypothèses concernant la phylogenie des Malacostracés (Crustacea, Malacostraca) (2éme partie)

. A revised classification of Malacostraca based on a phylogenetic analysis is presented. For this purpose 68 morphological characters were cladistically treated using the parsimony programme Paup 4.10. The system here proposed is a reflection of the cladistic tree produced by TABACARU & DANIELOPOL (2011). The following aspects are in the present contribution developed: (1) We consider, in accordance with a widely held opinion of carcinologists, that Phyllocarida (Ord. Leptostraca) displays essential synapomorphies with Malacostraca, namely tagmosis 5+7+8+telson, fixation of the gonopore on the 6th female thoracic-segment and on the 8th male-thoracic segment. Based on this assertion Phyllocarida belongs to the Class Malacostraca. Hence we do not share either the ancient view of H. MILNE EDWARDS (1840), who included Nebalia into the Ordo Phyllopodes, Legio Branchiopodes Latreille, or the more recent opinions of SCHRAM (1986), WHEELER (1997) and WILLS (1998) who consider Phyllocarida as belonging to Phyllopoda; (2) the Class Malacostraca is dichotomously separated into Subclasses, Phyllocarida and Eumalacostraca. This is due to the fact that Hoplocarida shares essential synapomorphies with the Eumalacostraca, namely loss of 7th somite of the pleon, thoracic endopod built as stenopod and pleopods of the 6th somite of pleon differentiated as uropods. This opinion is in contradiction with those of other carcinologists who, presupposing a distinct origin of Hoplocarida, consider the Class Malacostraca separated in three Subclasses: Phyllocarida, Hoplocarida and Eumalacostraca (SCHRAM, 1978, 1981; MCLAUGHLIN, 1980; BOWMAN & ABELE, 1982; KUNZE, 1983; DAHL, 1983; AHYONG, 1997; MARTIN & DAVIS, 2001; WELLS & HOUSTON, 2002; FOREST, 2004 ); (3) in our opinion the Superorder Syncarida Packard, 1885 (including the orders Bathynellacea Chappuis, 1915 and Anaspidacea Calman, 1904) does not represent a monophyllum. We accept the view of SERBAN (1972) following which Bathynelacea represents a separate taxon called Podophallocarida (SERBAN, 1970). This decision is based especially on the absence in this group of a cephalotorax and maxillipeds, the lack of petasma, the telson with furcal rami and the 8th thoracopod transformed into a penis. For the sister group of the Podophallocarida we propose a new Infraclass, Cephalothoracarida (nov.). This latter taxon is defined by the first thoracomer fused to the cephalon and forming the cefalothorax, the 1st thoracopod differentiated as maxilliped and the telson without furca. Therefore Anaspidacea remains the solely order within th