AN UPDATED KEY TO THE GENERA OF CALIGIDAE (COPEPODA: SIPHONOSTOMATOIDA).

Members of the copepod family Caligidae are some of the most common parasites of marine fishes. There are 503 recognized species divided into about 30 genera, with 75% of species belonging to the 2 largest genera, Caligus and Lepeophtheirus. More than 30 caligid species are known to cause serious pathologic changes as ectoparasites in marine teleost aquaculture.

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The parasitic copepod Kollar, 1835, infects the freshwater bream, , a key species in European freshwater ecosystems. Despite its widespread occurrence and potential to cause skin hemorrhages, scale erosion and perforation, and fish mortality, species-level identification within the genus has been problematic due to insufficient diagnostic traits. This study refines identification criteria by integrating morphological and genetic approaches.

A SYSTEMATIC REVISION OF KROYERIA (COPEPODA: SIPHONOSTOMATOIDA): FIVE NEW SPECIES, 11 REDESCRIPTIONS, AND A MORPHOLOGICAL PHYLOGENETIC ANALYSIS OF THE GENUS.

This study focuses on the taxonomy and systematics of Kroyeria, a genus of ectoparasitic copepods found on the gills of sharks. Members of the genus Kroyeria exhibit species-specific appendage ornamentation, including denticles, membranes, and setules, in addition to the setae and spines typical of most copepods. The taxonomy and systematics of Kroyeria have been hampered by the lack of observation of these fine morphological details.

Copepod phylogenomics supports Canuelloida as a valid order separate from Harpacticoida.

Copepods are small crustaceans that are ubiquitous in aquatic environments. They are particularly abundant in marine and freshwater plankton, marine sediments, and as parasites or commensals of other aquatic organisms. Despite their abundance and importance, phylogenetic relationships among copepods are poorly resolved.

Two new species of planktonic Caligus O.F. Müller 1785 (Copepoda: Caligidae) from Türkiye with an updated review and checklist of planktonic caligids.

Two new species of caligid sea lice, Caligus izmiriensis sp. nov., and Caligus sarosensis sp.

Caligus minimus Otto, 1821 (Copepoda: Caligidae): A commercially important but poorly described parasite of cultured European Sea Bass, Dicentrarchus labrax (Linnaeus, 1758).

Caligus minimus Otto, 1821 has been known for over two centuries and it is the second oldest of the approximately 275 species of Caligus O. F. Müller, 1985.

A new genus of Herpyllobiidae (Copepoda: Cyclopoida) from a deep-living annelid (Polychaeta: Sigalionidae).

A taxonomic study of deep-sea polychaetes collected at a depth of 2,805 m off the northern coast of California revealed a scaleworm of the family Sigalionidae with an attached parasitic copepod. The copepod represents an undescribed genus of the family Herpyllobiidae, comprising mesoparasitic copepods chiefly recorded from polychaetes of the family Polynoidae. Blakerius gen.

Ectoparasites of the Critically Endangered green sawfish Pristis zijsron and sympatric elasmobranchs in Western Australia.

This study reports the metazoan ectoparasite fauna of juvenile Critically Endangered green sawfish, Pristis zijsron, and sympatric elasmobranchs in Western Australia. Five parasite taxa were found on 76 screened P. zijsron: Caligus furcisetifer (Copepoda: Caligidae), Dermopristis pterophila (Monogenea: Microbothriidae), Branchellion plicobranchus and Stibarobdella macrothela (Hirudinea: Piscicolidae), and praniza larvae of an unidentified gnathiid isopod.

MicroCT illuminates the unique morphology of Shiinoidae (Copepoda: Cyclopoida), an unusual group of fish parasites.

The copepod family Shiinoidae Cressey, 1975 currently comprises nine species of teleost parasites with unusual morphology and a unique attachment mechanism. Female shiinoids possess greatly enlarged antennae that oppose a rostrum, an elongate outgrowth of cuticle that originates between the antennules. The antennae form a moveable clasp against the rostrum which they use to attach to their host.

Resolving taxonomic and nomenclatural problems in the genus Caligus O.F. Mller, 1785 (Copepoda: Caligidae).

Supplementary descriptions are provided for six poorly known species of Caligus, based on a study of type and other material carried out by the late Roger F. Cressey but never published. As part of that study new illustrations were produced by Hillary Boyle Cressey who has kindly made these previously unpublished drawings available to this paper.

Exploring evolutionary trends within the Pennellidae (Copepoda: Siphonostomatoida) using molecular data.

The family Pennellidae comprises ecto- and mesoparasitic copepods on marine fishes. Although a preliminary scheme of phylogenetic relationships of pennellids based on morphological characters exists, it is difficult to objectively define character states because of their highly modified bodies and reduced appendages. This molecule-based study analysed phylogenetic relationships among seven genera and 12 species of pennellids, using 18S and 28S ribosomal DNA sequences in order to infer evolutionary trends within the family.

A synthesis tree of the Copepoda: integrating phylogenetic and taxonomic data reveals multiple origins of parasitism.

The Copepoda is a clade of pancrustaceans containing 14,485 species that are extremely varied in their morphology and lifestyle. Not only do copepods dominate marine plankton and sediment communities and make up a sizeable component of the freshwater plankton, but over 6,000 species are symbiotically associated with every major phylum of marine metazoans, mostly as parasites. Unfortunately, our understanding of copepod evolutionary relationships is relatively limited in part because of their extremely divergent morphology, sparse taxon sampling in molecular phylogenetic analyses, a reliance on only a handful of molecular markers, and little taxonomic overlap between phylogenetic studies.

Sea lice (Copepoda: Caligidae) from South Africa, with descriptions of two new species of Caligus.

Thirteen species of sea lice (family Caligidae) are reported from a range of elasmobranch and actinopterygian fishes caught off South Africa or obtained from public aquaria in South Africa. Two new species of Caligus Müller, 1785 are described: C. linearis n.

The cephalothoracic sucker of sea lice (Crustacea: Copepoda: Caligidae): The functional importance of cuticular membrane ultrastructure.

Sea lice adhere to the body surface of host fish with a cephalothoracic sucker. Caligus adheres to this substrate using legs 2 and 3, and the action of cephalothoracic muscles. Lunules, small, paired, anterior sucker-like structures, have a vital function in the initial step of adhering and contain a unique endocuticule containing elements that may behave like active matter and serve as the actuating mechanism.

Caligus tunisiensis n. sp. (Copepoda: Caligidae) parasitic on the painted comber Serranus scriba (L.) (Perciformes: Serranidae) from the Mediterranean Sea, off the Tunisian coast.

A new species of parasitic copepod, Caligus tunisiensis n. sp. (Caligidae), is described based on two female specimens collected from the gills of the painted comber, Serranus scriba (L.

Caligus madeirensis sp. nov. (Copepoda: Caligidae) Parasitic on Pompano, Trachinotus ovatus (Linnaeus, 1758), from Eastern Atlantic Waters, Surrounding the Madeira Archipelago, Portugal.

Introduction: A new species of the genus Caligus is described based on specimens collected from pompano, Trachinotus ovatus (Linnaeus), caught in eastern Atlantic waters, near the Madeira archipelago.

Methods: Pompano (n = 21) were purchased from the local fish market and examined for parasitic copepods. Morphological features of the copepods were examined and drawn using an Olympus BX51 equipped with a drawing tube.

Two new species of the genus (Crustacea, Copepoda, Siphonostomatoida) from the Sea of Japan, with a note on the establishment of a new species group.

Two new species of are described from the Japanese coast of the Sea of Japan. is based on a male specimen found in a plankton sample, whereas was collected from the body surface of the host flathead sp. These two new species can be assigned to a distinct species group, the group newly named and defined by the morphology of the genital complex in both sexes, and by the structure and armature of legs 2 and 4.

Re-description of Azygokeras columbiae Koeller amp; Littlepage, 1976 (Calanoida: Aetideidae) and musculature of the male grasping antennule.

Azygokeras columbiae from Bute Inlet, British Columbia, Canada, is re-described, correcting some details and adding information not available in the original description. Azygokeras columbiae is unique amongst male Aetideidae in having the right antennule modified for grasping but without a true knee joint (geniculation) between segments XX and XXI nor a hiatus in the musculature at this joint, typical of taxa with a geniculate male antennule. Male Azygokeras have wide pivot points and arthrodial membranes between segments XXI and XXII, XXIII and XXIV and XXV and XXVI that allow greater movement in several planes than in homologous segments of Euaugaptilus and Heterorhabdus.

The discovery of Lepeophtheirus lichiae Barnard, 1948 (Copepoda: Caligidae) parasitic on leerfish, Lichia amia (Linnaeus) in the Mediterranean Sea.

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 was collected from the dorsal body surface of the leerfish, Lichia amia (Linnaeus) caught in north-eastern Mediterranean waters off the Turkish coast. The original and only available description of L.

Two new species of parasitic copepods from the genera and (Cyclopoida: Bomolochidae) from Australian waters.

A 2016 collaborative survey of commercial fish parasites in Moreton Bay, Queensland, Australia led to the discovery of two new species of parasitic copepods belonging to the family Bomolochidae. Females of n. sp.

A new species of Clausidium Kossmann, 1874 (Copepoda: Cyclopoida) associated with ghost shrimps from the Persian Gulf, including female-male interlocking mechanisms and remarks on host specificity.

A new clausidiid copepod was found associated with the ghost shrimp Neocallichirus jousseaumei (Nobili) in the Persian Gulf, on the Iranian coast. The new species shares the armature formula of swimming legs 2 to 4 with C. persiaensis, but can be easily distinguished from its congeners by unique characteristics of the females: the prominent spine on endopodal segment 1 of the antenna, the armature of the maxilliped, and the elongated basis of the swimming legs.

The re-discovery of Caligus lichiae Brian, 1906 (Copepoda: Caligidae) parasitic on two carangid fishes in the Mediterranean Sea, and the recognition of Caligus aesopus Wilson C. B., 1921 as a junior subjective synonym.

The caligid copepod Caligus lichiae Brian, 1906 is redescribed based on new material collected from the type-host, Lichia amia (Linnaeus), and from a second carangid, Seriola dumerili (Risso), both caught in the Gulf of Iskenderun, Turkey. Key diagnostic characters of both sexes are reported, supported by drawings and scanning electron microscopy images. Despite the commercial importance of its type-host, L.

A new species of Peniculus (Copepoda: Siphonostomatoida) parasitizing mesopelagic myctophid fish: first discovery of colonization of the genus in deep water.

Peniculus hokutoae n. sp. is described on the basis of an ovigerous adult female parasitizing the caudal fin of the myctophid fish Symbolophorus evermanni (Gilbert, 1905), collected from Suruga Bay, Japan.

Caligus mulli n. sp. (Copepoda: Caligidae) parasitic on two Mullid fishes from the eastern Mediterranean and adjacent Atlantic waters.

A new species of caligid copepod, Caligus mulli n. sp., is described based on specimens collected from surmullet Mullus surmuletus Linnaeus from Atlantic waters off the Azores, Portugal, and from red mullet Mullus barbatus barbatus (Linnaeus) caught in the Mediterranean Sea, off the south-eastern coast of Turkey.

The discovery of Lepeophtheirus acutus Heegaard, 1943 (Copepoda: Caligidae) from two new elasmobranch hosts in the Mediterranean Sea, and a comparative redescription of Lepeophtheirus rhinobati Luque, Chaves et Cezar, 1998.

In this study, supplementary information on the morphology of the siphonostomatoid copepod Lepeophtheirus acutus Heller, 1865 is given based on new material collected from the ventral body surface and mouth cavity of common guitarfish, Rhinobatos rhinobatos (Linnaeus) and from the branchial cavity of bull ray, Aetomylaeus bovinus (Geoffroy Saint-Hilaire) caught in Iskenderun Bay, Turkey. This is the first report of L. acutus from Mediterranean waters.