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In the framework of an ongoing extensive phylogenetic evaluation of the Ceratonotus group (Copepoda, Harpacticoida, Cletodidae), Poropsyllus menzelae gen. et sp. nov. from the sublittoral of south-western Cyprus (eastern Mediterranean Sea) and Paratouphapleura aaroni gen. et sp. nov. from the western Weddell Sea (Antarctica) are described. Both new species fit the autapomorphies of the Ceratonotus group but cannot be assigned to any of the genera so far known. Instead, each new species presents a set of derived characters that justify their placement in new genera, Poropsyllus gen. nov. and Paratouphapleura gen. nov., respectively. Furthermore, a comparison of the species placed in Ceratonotus Sars revealed that because of exclusive morphological deviations, Ceratonotus concavus Conroy-Dalton, C. steiningeri George, C. tauroides George, and C. vareschii George should be excluded from Ceratonotus and transferred to a new monophylum, Tauroceratus gen. nov. Likewise, Polyascophorus monoceratus George, Wandeness & Santos is characterized by several apomorphies that justify its transfer from Polyascophorus to a new taxon, Pseudopolyascophorus gen. nov. The Ceratonotus group is therefore increased to 31 species assigned to 13 genera. The systematic modifications conducted and resulting phylogenetic consequences are discussed in detail.
The finding of Breviconia andrei sp. nov. in the Russian Bering Sea enabled the clear-cut phylogenetic characterization of the former monotypic genus Breviconia Conroy-Dalton & Huys, 2000 as a monophylum. Comparison of the new species with B. australis (George, 1998) and other members of the subfamily Ancorabolinae Sars, 1909 yielded four autapomorphies that unambiguously support the monophyletic state of Breviconia: (1) an elongated and approximately 90°-curved mandibular gnathobase, (2) reduction of the maxillar endopod, (3) maxillar endites carrying 2 instead of 3 setae, and (4) loss of the minute seta on the maxillipedal claw. For B. andrei sp. nov., two autapomorphies could be detected, namely, (1) the development of dorsal tubercles on the P5-bearing body somite and (2) the remarkable elongation of the first endopodal segment of the first swimming leg that is twice as long as the whole exopod. Of particular interest is the presence of a 3-segmented endopod in the third swimming leg of the male of B. andrei sp. nov. It disproves the current assumption that the Ancorabolinae are characterized by (among others) the derived presence of an only 2-segmented endopod in the male’s third swimming leg.
It appeared necessary to undertake a redescription of Laophontodes typicus T. Scott, 1894, but with the absence of the type specimen, several additional individuals collected from a number of regions were studied. The specimens chosen were from the western coast of Sussex and the Scottish Firth of Forth (UK), the Skjerstad fjord (Norway), the Patagonian continental slope (Chile) and the Great Meteor Seamount (subtropical north-eastern Atlantic Ocean). All specimens examined had been previously determined as L. typicus and deposited in the collections of renowned research institutions.
However, detailed morphological comparison revealed that only the Sussex material can be assigned to L. typicus; the remaining specimens represent distinct species whose original assignment to L. typicus was erroneous, due to a morphological ambiguity. Thus, the current status of L. typicus must be regarded as a species complex. The Sussex material enabled a detailed redescription of L. typicus. Additionally, five new species are described, namely L. scottorum sp. nov., L. sarsi sp. nov., L. gertraudae sp. nov., L. monsmaris sp. nov. and L. norvegicus sp. nov. They exhibit some morphological similarity, but equally present discrete characters justifying their establishment as distinct taxa. The descriptions are
accompanied by a detailed discussion that explains the justification of the splitting of L. typicus.