This work focuses on aspects of reproductive biology of Sardina pilchardus from the Atlantic coast of Morocco. The mean values of batch fecundity estimated for the species is 23 150 (±1301) oocytes for a mean size of 19.5 (±0.49) cm, the mean relative fecundity being 346 (±7.34) oocytes per gram of female without ovary. Batch fecundity increases with total length and body weight without ovary. Sizes at first sexual maturity (L 50 ) are reached for males and females at 15.8 (±0.29) cm and 15.8 (±0.35) cm, respectively. The spawning period for the population extends between October and July and the spawning peak occurs from October to February. However, the small sardines (14.5-17 cm) in their first reproduction spawn between November and June, whereas larger fish (17.5-25 cm) spawn between October and July. The factor of condition (K) increased in summer during the sexual resting phase. It is weak in winter during the period of reproduction. Regarding, the sex ratio, there was no significant difference in the number of males and females. To cite this article: K.

Two of these species are mainly distributed in Mediterranean (S. macrostigma) and Atlantic (S. pellegrini) river basins while the other two species are restricted to isolated lakes in the Atlas Mountains, one of them to Ifni Lake (S. akairos) and the other, probably extinct, to Sidi Ali Lake (S. pallaryi). Preliminary phylogenetic and regional studies based on molecular data have found high structuration of the populations of this genus in Morocco. These studies focused on allozymes, microsatellites and mitochondrial markers found genetic differences in populations from Isli Lake (Atlas Mountains) and the Draa Basin in southern Morocco. In this work we provide different morphological and genetic traits to distinguish these populations from Isli Lake and Draa Basin as two different species.

The genus Luciobarbus Heckel, 1843 is characterized by medium to large fish species occurring in large rivers and downstream zones with slow-moving waters. Remarkably also rheophilic Luciobarbus occur in Morocco, which are of small size and exhibit distinct morphological traits as well as different habitat requirements. These rheophilic species have traditionally been assigned to Luciobarbus nasus (Günther, 1874) and L. magniatlantis (Pellegrin, 1919), although some authors consider L. magniatlantis as a junior synonym of L. nasus. This lack of consensus on the taxonomy of rheophilic barbs is constrained by limited population studies that do not encompass their entire distribution range. Using molecular, morphometric, and osteological data we studied populations of rheophilic barbs of three drainage basins in which they are currently present: Tensift, Moulouya and Oum er Rbia. Our results clearly identified the rheophilic barbs of each basin as different species. The species Luciobarbus magniatlantis is a well-recognized species endemic to Tensift Basin. In contrast, the investigated populations from the Moulouya and Oum er Rbia basins could not be assigned to any previously described species. Consequently, we describe two new Luciobarbus species in the Moulouya and Oum er Rbia basins.

The genus Luciobarbus in Morocco presents high diversification, in contrast to the generally impoverished freshwater fish fauna from North Africa. Within Morocco the northern area is one of the least studied territories, due to both its historical background and the limited accessibility of many regions. Previous phylogenetic studies identified Luciobarbus populations that are morphologically and genetically differentiated, to the same extent as others already recognized as separate species. The aim of this work is to describe these populations as distinct species, based on morphological, meristic, and genetic traits.

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants generated primarily during the incomplete combustion of organic materials (e.g., coal, oil, petrol, and wood). Many PAHs have toxic, mutagenic, and/or carcinogenic functions. PAHs are highly lipid soluble which lead to a fast absorption by the gastrointestinal tract of marine mammals. They are immediately distributed in a vast variety of tissues with a notable tendency for localization in body fat. Metabolism of PAHs is obtained via the cytochrome P450-mediated mixed function oxidase system with oxidation or hydroxylation as the first step. PAHs are environmental contaminants that pose significant risk to health of fish. The effect of PAHs on fish is a topic of rising attention in a lot of countries. Different studies using the bile metabolites separated by high-performance liquid chromatography with fluorescence detection were presented. The aim is to compare the levels of PAH metabolites in fish from different areas and fish species. The major metabolite present in all fish was 1-hydroxypyrene. The data confirm the importance of 1-hydroxypyrene as the key PAH metabolite in fish bile and suggest that the European eel is an ideal species for monitoring PAHs.