The distribution and abundance of Lernaeocera lusci (Copepoda) on hake (Merluccius merluccius) and bib (Trisopterus luscus) (Teleostei).

Distribution patterns, mean intensity and prevalence of Lernaeocera lusci (Copepoda, Pennellidae) in its hosts Trisopterus luscus (Teleostei, Gadidae) and Merluccius merluccius (Teleostei Merlucciidae) were examined, together with parasitic abundance and aggregation in relation to the size of the host. The mean parasite abundance and variance to mean abundance ratio increased with host size, suggesting that the accumulation of this parasite had no noticeable impact on the structure of either host population. Merluccius merluccius being a newly colonized host in the Mediterranean, these results are discussed in relation to current ideas on the evolution of pathogenicity in heterospecific associations.

[Biosystematic study of two populations of teleosts (Sardina pilchardus) and their copepod parasites (Peroderma cylindricum) from the Tunisian coast]. / Etude biosystématique de deux populations de teléostéens (Sardina pilchardus) et de leurs copédodes parasites (Peroderma cylindricum) sur les côtes tunisiennes.

A genetic analysis realized, on Tunisian coasts, within and between two populations of a Teleostean (Sardina pilchardus) on one hand, and two populations of their parasitic Copepods (Peroderma cylindricum) on the other hand, reveal that: (l) the 14 loci analysed are monomorphic in the Teleostean populations; (II) 3 loci among 13 investigated are polymorphic in the Copepod populations. Statistical tests from deviations of Hardy-Weinberg equilibrium and genotypic homogeneity show the existence of strong gene flows within and between Copepod populations. Thus, it seems that the Teleostean (Sardina pilchardus) and the Copepod (Peroderma cylindricum) constitute at least on Tunisian coasts, two homogeneous taxinomic units.

[Parasitic copepods of fish from the coasts of Montenegro (South Adriatic)]. / Copépodes parasites des poissons des côtes du Montenegro (Adriatique Sud).

Twenty-five species of parasitic copepods are presented, collected on fishes living in the Montenegro sea coasts. Among these species, belonging to ten families and sixteen different genera, fifteen are new records for the Adriatic Sea.

Characterization of two species of Lepeophtheirus (Copepoda, Caligidae) from flatfishes. Description of Lepeophtheirus europaensis sp. nov.

In the eastern Mediterranean, the copepod Lepeophtheirus thompsoni Baird, 1850, has been reported to infest turbot, brill and flounder. By combining several methods, including enzyme electrophoresis, we show that this species is found only in turbot. By contrast, brill and flounder are infested by a species of Lepeophtheirus that corresponds to no other species reported in the literature. We propose that the species be designated as L. europaensis and we describe the characteristics of the gravid female. This study was extended to the Atlantic populations of flatfishes and includes an investigation of L. pectoralis (Muller, 1776), which infects flounder in the North Sea; we also confirmed the presence of L. thompsoni (Baird, 1850) over the whole geographic range of turbot. Lastly, we discuss the specificity and distribution of these species along the European coasts.

[Copepode parasites of fish from the Kerkennah Islands (Southern Tunisia)]. / Copépodes parasites de poissons des Iles Kerkennah (Tunisie méridionale).

Out of 29 species of fish from the Kerkennah Islands examined, 30 species of parasitic copepoda were collected which belong to seven families and nine different genera. Among them three new species have been found and ten were reported for the first time in Tunisia.

[Life cycle of Leranthropus kroyeri Van Beneden 1851, hematophagous branchial copepod of the sea bass Dicentrarchus labrax (Linné, 1758) in wild and experimental populations]. / Cycle évolutif de Lernanthropus kroyeri Van Beneden, 1851, Copépode branchial hématophage du loup Dicentrarchus labrax (Linné, 1758) dans des populations naturelles et en élevage.

The life cycle of Lernanthropus kroyeri Van Beneden, 1851, copepod (Siphonostomatoida) parasite of Dicentrarchus labrax is described. The cycle comprises two nauplii, one infective copepodid, four fixed copepodids and one preadult. All the attached stages are caracterised by the lack of the frontal filament. This is the first description of a life cycle lacking a chalimus for Siphonostomatoida Copepods parasitic on fish.

[Experimental realization of the life cycle of Ergasilus lizae Kroyer, 1853, parasitic Copepoda of the fish Mugilidae. First results of infestation]. / Réalisation expérimentale du cycle évolutif de Ergasilus lizae Kroyer, 1863, Copépode parasite de Poissons Mugilidés. Premiers résultats de l'infestation.

The life cycle of the parasitic Copepoda Ergasilus lizae with the infestation of a Mullet belonging to the species Liza aurata were obtained experimentally. The first results on the larval development process and the spreading over the branchial microbiotope by parasitic females are described.

[Colobomatoides splendidus n.g., n.sp. (Copepoda, Philichthyidae), a parasite of teleost fishes of the species Sparus (Sparidae) from the Tunisian coast]. / Colobomatoides splendidus n. g., n. sp. (Copepoda, Philichthyidae) parasite de poissons téléostéens du genre Sparus (Sparidae) des côtes de Tunisie.

After examination of the mucus ducts of the cephalic system in two species of teleostean fish from the coasts of Tunisia, Sparus ehrenbegi and Sparus caeruleostictus (Sparidae), a parasitic copepod belonging to the Philichthyidae, Colobomatoides splendidus n.g., n. sp. was found. The morphological study of this copepod is carried out.

[Lernaepodidae, copepod parasites of Tunisian Sparidae]. / Les Lernaeopodidés, Copépodes parasites de Sparidés du Tunisie.

On the gills and branchial arch of eleven sparidae species, from different tunisian lagoons and sea, nine lernaeopodidae species (copepods parasites) have been taked. These copepods are belonging to three genera. A study of their morphology, illustrated by plates is realised.

[Reproduction and sexuality of parasitic copepods of fishes. I. The reproductive apparatus of Chondracanthus angustatus Heller, 1865: anatomy, histology, and spermiogenesis (author's transl)]. / Reproduction et sexualité des copépodes parasites de poissons. I. L'appareil reproducteur de Chondracanthus angustatus Heller, 1865: anatomie, histologie et spermiogenèse.

The pygmy males of Chondracanthus angustatus are fixed on the genital segment of the female on two anterior-ventral tubercules. The genital system is formed by two dorsal testes, two broad vas deferens and two seminal vesicles each one containing a spermatophore. Two types of cells can be seen in the interstitial tram: the sexual (normal and abortive) and the somatic ones. The plasmic and nuclear membranes joined together on one end of the spermatid; on the opposite pole, the mitochondria penetrate into the cytoplasmic expansions. The non-motile starfish spermatozoa present neither di-ferentiated acrosome nor centrioles. The male gametes are stocked in the spermatophore and enveloped by many kinds of secretions. Spermatozoa are discharged into the female integument folds and they reach the seminal receptacle with the help of the villosities movement; they stay there till fertilization occurs.