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31.
A new species of the rare arietellid genus Scutogerulus is described from deep hyperbenthic waters off Okinawa, southwestern Japan. This is the second species of the genus. Phylogenetically significant characteristics known only on the basis of the type species are confirmed by the discovery of the new congener, in particular: (1) the genital system of the female exhibits the most plesiomorphic condition of any arietellid genus; (2) the well developed setae on the endopodal segments of the maxillae and maxillipeds are modified into ‘shield‐like setae’ similar to the ‘button setae’ in another arietelloidean family, the Augaptilidae; (3) the outer distal spine on the first exopodal segment of leg 1 is absent.  相似文献   
32.
A new species of cyclopoid copepod, Diacyclops biceri sp. nov., is described from Lake Baikal. It was found in the interstitial water of a sandy beach at Buchta Peschanaya on the western shore of the central basin of Baikal. The new species is unique in possessing 2-segmented endopods in swimming legs 3 and 4. Swimming legs 2 to 4 have 3-segmented exopods. The slender body form, the lack of the antennal exopodal seta, and the presence of a secondary pseudosomite anterior to the genital double somite of the adult female are interpreted as adaptations to the interstitial habitat. The harpacticoid Epactophanes richardi Mrazek was found in the same interstitial habitat as D. biceri.  相似文献   
33.
The tantulus larva ofMicrodajus langi is redescribed using Scanning Electron Microscopy. Thoracopods 2–5 have poorly developed but fully armed endites. Thoracopods 1–5 are biramous, with each ramus represented by a minute segment. A new species,M. pectinatus, is described from a tanaid host collected in the Rockall Trough, off the west coast of Scotland. A system of homologies for the portopodal segments of the thoracopods of the tantulus larva is proposed. Some aspects of the musculature of the adult male are described for the first time.  相似文献   
34.
The existing systematics of the Chondracanthidae is based predominantly on female characters and divides them into two subfamilies: Chondracanthinae and Lernentominae. Phylogenetic analyses using maximum parsimony were performed using 186 male and female characters. Different trees were generated when male and female characters were analysed separately. Differential weighting showed that the female characters were dominant but not to a great extent and subsequent analyses were run with both partitions combined. Different trees were generated depending on the character setting (unordered, ordered and irreversible-up). Interestingly, a basal backbone comprising the same nine ingroup taxa was present in all of the trees, although the sequence of those taxa could differ. Constraining the two subfamilies to be monophyletic caused the tree length to be increased and the Templeton and Kishino–Hasegawa tests showed the constrained tree to be significantly different from the unconstrained. The two subfamilies are considered invalid and Lernentominae Oakley, 1927 is formally synonymized with Chondracanthinae Milne Edwards, 1840. The validity of the Pharodidae was tested similarly. Pharodes tortugensis , representing the family Pharodidae, was always recovered nested deep within Chondracanthidae. The Pharodidae Illg, 1948 is therefore synonymized with the Chondracanthidae Milne Edwards, 1840.  相似文献   
35.
Paramacrochiron thailandicum n. sp. (Copepoda: Cyclopoida: Macrochironidae) is described from the rhizostome medusa Rhopilema hispidum occurring in the Gulf of Thailand. The new species is distinguishable from other congeners mainly by detailed features of the fourth legs and the urosome in both sexes. Copepodid and adult stages of the genus Paramacrochiron seem to be host-specific to rhizostome medusae, but may spend periods free in the plankton or benthos during the absence of the host. A cladistic analysis shows that the Macrochironidae comprises two main lineages. Paramacrochiron is recovered as a monophyletic group, located on one lineage together with Pseudomacrochiron, which appears as a paraphyletic taxon with the limited character set used. The other main lineage comprises the genera Macrochiron and Sewellochiron, but the sole species of the latter genus, Sewellochiron fidens, is nested within Macrochiron. This analysis provides little support for maintaining Sewellochiron as a separate genus.  相似文献   
36.
A new species of parasitic copepod of the family Lernanthropidae is described from an immigrant population of the blotchfin dragonet Callionymus filamentosus Valenciennes (family Callionymidae) in the Eastern Mediterranean. Both sexes are described on the basis of material caught in Egyptian waters off the Alexandria coast at Abuqir. The new species shares with Lernanthropus breviculus Kabata, 1979 the possession of a small dorsal plate on the trunk that is so narrow at its origin that it does not overlap the bases of the fourth legs, which are therefore visible in dorsal view. These species differ in the shape of the cephalothorax and in the extent of the dorsal plate, which is shorter in the new species, revealing the caudal rami in dorsal view. Previous records of parasitic copepods utilising callionymids as hosts are reviewed: most belong to the families Pennellidae and Chondracanthidae.  相似文献   
37.
38.
Tripaphylus musteli (van Beneden, 1851) (Copepoda, Siphonostomatoida, Sphyriidae) is redescribed from an adult female collected from the branchial chamber of a starry smooth-hound, Mustelus asterias Cloquet (Carcharhiniformes, Triakidae), captured in the English Channel off Portland, UK. The new account of T. musteli is the first based on a complete adult female and highlighted the lack of a robust distinction separating Tripaphylus Richiardi, in Anonymous, 1878 and Paeon Wilson, 1919 prompting us to relegate Paeon to a junior subjective synonym of Tripaphylus. In the light of this synonymy the eight former species of Paeon are transferred to Tripaphylus as follows: T. ferox (Wilson, 1919) new combination, T. elongatus (Wilson, 1932) new combination, T. vassierei (Delamare Deboutteville & Nuñes-Ruivo, 1954) new combination, T. lobatus (Kirtisinghe, 1964) new combination, T. asymboli (Turner, Kyne & Bennett, 2003) new combination, T. versicolor (Wilson, 1919) new combination, T. australis (Kabata, 1993) new combination, and T. triakis (Castro Romero, 2001) new combination. Comparisons between terminology used in this report and that in the literature indicate that all transformed adult females of Tripaphylus probably possess a full complement of cephalic appendages and maxillipeds. All limbs, with the exception of the maxillae share a general morphological similarity to the corresponding appendages of conspecific males. The maxilla of the transformed adult female of Tripaphylus is a small digitiform protuberance associated with a swelling in some species.  相似文献   
39.
Systematic Parasitology - Lepeophtheirus lichiae Barnard, 1948 (Copepoda: Caligidae), a very rare and poorly known sea louse, is redescribed based on a single newly collected female. The specimen...  相似文献   
40.
Systematic Parasitology - Two new species of the genus Tripaphylus Richiardi in Anonymous, 1878 (family Sphyriidae) are described from elasmobranch hosts caught as bycatch within the Demersal and...  相似文献   
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