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Ahmed Kerfouf

  • Biodiversity Journal, 4 (2): 269-274

    Lyamine Mezedjri, Ahmed Kerfouf & Ali Tahar
    Reproductive cycle of the European anchovy Engraulis encrasicolus (Linnaeus, 1758) (Clupeiformes Engraulidae) in the gulf of Skikda (Algerian East coasts)

    ABSTRACT
    A study on the sexual cycle of the European anchovy, the pelagic fish Engraulis encrasicolus (Linnaeus, 1758) (Clupeiformes Engraulidae), was carried out in Algerian East coasts over a year (July 2008-June 2009). Annual sex-ratio (SR) showed that females dominate with an average male sex-ratio of 39.35%. The European anchovy spawning period ranges from April to October with peaks in the warmest months, strictly dependent on temperature. The gonado-somatic index was updated monthly which allowed us to divide the entire cycle into four successive phases: (i) a phase of slow maturation which occurs between the end of winter and the beginning of spring; (ii) a phase of significant sexual activity; (iii) a phase of emission of the sexual products which corresponds to the warmest months; and, finally, (iv) a phase of sexual rest occurring in the coldest months. Monthly variation of either hepato-somatic index or mesenteric fat reserves informed us about the origin of the energetic deposits, particularly important for the development of the gonads. In both sexes, the first sexual maturity is reached at a fish total length (Lt) of 12.5 cm.

  • Biodiversity Journal, 3 (3): 173-178

    Maya Meriem Hassani, S. Ahmed Kerfouf & Nawel Amel Brahim Tazi
    Metoncholaimus sp. (Nematoda Oncholaimidae) pseudoparasite of Mullus surmuletus (Linnaeus, 1758) (Perciniformes Mullidae) in the western Algerian Sea

    ABSTRACT
    This study was carried out between October 2009 and July 2010 to determine nematode parasites of the red stripped mullet, Mullus surmuletus (Linnaeus, 1758), in the gulf of Oran (western Algeria), located at 35°43’ N - 0°37’ W. A total of 100 fishes caught from the local fishermen by gill-net were investigated. Our investigation revealed the presence of three nematodes (one female and two males) located in the intestine of two infected fishes, these nematodes were alive and not attached to the mucosa of the fish host. The examination of the nematodes recovered showed that they belong to the genus Metoncholaimus Filipjew 1918 (Oncholaimidae Oncholaiminae). These nematodes are free living mostly in the coastal marine sediment; Mullus surmuletus might acquire them accidentally while either feeding on them or along with other food items taken from the bottom.

  • Biodiversity Journal, 13 (3): 0483-0494

    Fayza Belmokhtar, Rahma Belmokhtar, Ahmed Kerfouf & Mohammed Bey Baba Hamed
    Morphometric analysis of three Mediterranean limpets Patella caerulea Linnaeus, 1758, P. rustica Linnaeus, 1758 and the endangered P. ferruginea Gmelin, 1791 (Gastropoda Patellidae) from the Algerian West Coast
    https://doi.org/10.31396/Biodiv.Jour.2022.13.3.483.494

    ABSTRACT
    The characterization of Patella caerulea Linnaeus, 1758, P. rustica Linnaeus, 1758 and P. ferruginea Gmelin, 1791 (Gastropoda Patellidae) has been a source of debate and controversy since they were proposed as species. This was due to the high shell variability, and some of them display intermediate characteristics. In the present work, samples of three species of Patella were examined and compared using several morphometric characters describing the shell and soft parts. 575 individuals of P. caerulea, 132 individuals of P. rustica, and 45 of P. ferruginea were sampled from Algerian West Coast. The biometry of the three species has been studied: length (L), width (Wi), height (H) of the shell and the weight (W) of every individual. A strong positive correlation was noted between these parameters for all three species. These parameters were used also for the Principal Component Analysis (PCA). The three Patella species showed substantial morphology variability. P. rustica was easily recognized due to small brown spots near the shell apex. P. ferruginea (lamarckii form, rouxii form) were well identified from the other Patella species but for P. caerulea, a high morphological variability was noted between us in studied localities.