A new genus and species, Avitocaligus assurgericola gen. et sp. n., of the family Caligidae is established based on an ovigerous female collected from a razorback scabbardfish, Assurger anzac (Alexander), caught off New Caledonia. This is the first record of any parasitic copepod from this fish. The new genus is placed in the Caligidae since it possesses the caligid cephalothorax incorporating the first to third pedigerous somites. It also exhibits biramous first and fourth swimming legs but lacks dorsal plates on the fourth pedigerous somite. This combination of characters serves to differentiate the new genus from existing genera. In addition, it possesses loosely coiled, uniseriate egg sacs, concealed between the middle lamellar plates on the genital complex and the ventral plates on the abdomen. Preliminary phylogenetic analysis with a restricted matrix suggests that the new genus represents the earliest offshoot from the main caligid lineage since it does not exhibit the dominant exopod on the fourth swimming leg found in all other members of the Caligidae, including the genus Euryphorus. It strongly supports the newly recognized monophyletic status of the Caligidae, incorporating the genera formerly placed in the Euryphoridae.
A new genus, Alanlewisia, of the family Caligidae is established to accommodate a sea louse species originally, but tentatively, placed in the genus Lepeophtheirus by Lewis (1967). The type species is Alanlewisia fallolunulus (Lewis, 1967) comb. n., which is redescribed in detail based on new material collected from bluespine unicornfish, Naso unicornis (Forsskål), caught off New Caledonia in the South Pacific. This species was originally described by Lewis (1967) under the binomen Lepeophtheirus? fallolunulus from the same host species collected in Hawaii. This species was subsequently transferred to the genus Anuretes by Ho and Lin (2000). Lewis was uncertain of the generic placement primarily because of the possession, in the females only, of paired lunule-like structures on the ventral surface of the modified frontal plates. In both sexes the first swimming leg is biramous, with a well-developed endopod bearing 2 long, sparsely-plumose setae, and the third leg has a 2-segmented exopod. This combination of characters serves to differentiate the new genus from existing genera. Preliminary phylogenetic analysis suggests that the new genus represents an early offshoot from the main caligid lineage, basal to the Paralebion-Tuxophorus-Caligus clade identified by Boxshall and Justine (2005).
Over a 7-year period, parasites have been collected from 28 species of groupers (Serranidae, Epinephelinae) in the waters off New Caledonia. Host-parasite and parasite-host lists are provided, with a total of 337 host-parasite combinations, including 146 parasite identifications at the species level. Results are included for isopods (5 species), copepods (19), monogeneans (56), digeneans (28), cestodes (12), and nematodes (12). When results are restricted to those 14 fish species for which more than five specimens were examined and to parasites identified at the species level, 109 host-parasite combinations were recorded, with 63 different species, of which monogeneans account for half (32 species), and an average of 4.5 parasite species per fish species. Digenean records were compared for 16 fish species shared with the study of Cribb et al. (2002); based on a total of 90 parasite records identified at the species level, New Caledonia has 17 new records and only seven species were already known from other locations. We hypothesize that the present results represent only a small part of the actual biodiversity, and we predict a biodiversity of 10 different parasite species and 30 host-parasite combinations per serranid. A comparison with a study on Heron Island (Queensland, Australia) by Lester and Sewell (1989) was attempted: of the four species of fish in common and in a total of 91 host-parasite combinations, only six parasites identified at the species level were shared. This suggests strongly that insufficient sampling impairs proper biogeographical or ecological comparisons. Probably only 3% of the parasite species of coral reef fish are already known in New Caledonia.