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A specimen of Physiculus dalwigki Kaup, 1758 measuring 218 mm in total length, 190 mm in standard length, and weighing 90 g was caught off the northern Tunisian coast. This capture constitutes the first record of this fish from the Tunisian coast. The specimen is described including morphological measurements, meristic counts, and color. Due to a lack of records, the real status of the species in the Tunisian waters still remains questionable. Physiculus dalwigki occurs only off northern Spain and south to the Strait of Gibraltar in the waters surrounding Madera and the Azores Islands, and in the Mediterranean Sea from Nice (southern France) to the Tunisian coast. Therefore, it appears that P. dalwigki is displaying a disjoint distribution with the exclusion of a large western region of the Mediterranean Sea.

The first record of the little sleeper shark, Somniosus rostratus (Risso, 1827), from the Tunisian coast, is presented in this note. It was an adult female measuring 990 mm total length and weighing 4500 g. The capture occurred off Ras Jebel located in north-eastern Tunisia at a depth of 120 m. The specimen is herein described including morphological measurements, color, and dental formula. Due to a lack of records, the real status of the species in the Mediterranean Sea remains questionable. Somniosus rostratus is rarely caught in this sea because it lives in deep bottoms poorly exploited by commercial vessels. However, recent captures of specimens and occurrence of nursery grounds suggest that a viable population of S. rostratus is probably established in this sea.

The authors report in the present note the first confirmed record of Guinean amberjack, Seriola carpenteri Mather, 1971 in Tunisian waters, based on available specimens, captured in northern Tunisia, off Ras Jebel. The specimens are shortly described including morphometric measurements and meristic counts. Species distribution in the central Mediterranean Sea is commented and discussed. These new collected specimens indicate that a viable population of Seriola carpenteri is probably established in the area.

The authors present in this paper a new Mediterranean record of undulate skate Raja undulata Lacépède, 1802. The specimen was an adult male caught between Sète and Palavas, off the Languedocian coast (southern France); it measured 820 mm total length, 425 mm disc width and weighed 3750 g. The specimen is herein described with morphometric measurements, meristic counts and external morphology of claspers. The occurrence of this threatened species in the area and the Mediterranean Sea is discussed and commented. It appears that the origin of the Mediterranean specimens of R. undulata remains still questionnable.

The authors present in this paper the second Mediterranean record of milk shark Rhizoprionodon acutus (Rüppell, 1837) which is also the first record from the Tunisian coast. The specimen was captured off Zarzis in southern Tunisia, it is described together with a specimen caught off the Senegalese coast, used as reference for identification. The occurrence of the species in the area and the Mediterranean Sea is discussed and commented. It appears that the origin of the Mediterranean specimens of R. acutus remains still questionnable.

A Monrovian surgeonfish, Acanthurus monroviae Steindachner, 1892, was found for the first time off the Tunisian coast, in the Gulf of Tunis, northern Tunisia. The specimen is described with morphometric measurements, meristic counts and some biological observations. The occurrence of A. monroviae in the area and the Mediterranean Sea is discussed and commented.

The sandbar shark, Carcharhinus plumbeus, is landed in fishing sites located along the coast of Senegal (Eastern tropical Atlantic). The smallest mature male was 165 cm in total length (TL) and weighed 14 kg while the largest male reached 193.5 cm TL and weighed 32 kg. The smallest adult female was 179 cm TL and weighed 25 kg while the largest female was 225 cm TL and weighed 64 kg. Parturition occurred from April to June. The gestation period was estimated at twelve months, at most. Females appeared to reproduce every two years. Size and mass at birth were based on near-term embryos and neonates; it probably occurred between 58 and 65 cm TL (mean: 60.3 cm ± 1.55) and between 0.92 and 1.52 kg (mean: 1.08 kg ± 0.133). Litter sizes ranged from 4 to 12. Embryos and post-partum males did not significantly outnumber the females.

Reproduction of the sawback angelshark Squatina aculeata is presented with specimens captured off Tunisia (central Mediterranean) and off Senegal (eastern tropical Atlantic). The smallest adult male and adult female were 120 and 137 cm total length (TL), respectively, and weighed 12.7 and 22.0 kg, respectively. Above 122 cm TL for males and 143 cm TL for females, all the observed specimens were adult. The largest male and the largest female were 152 and 175 cm TL and weighed 24.0 kg and 32.0 kg, respectively. Males and females presented similar total length versus total mass relationships, although the latter were considerably heavier than the former. Size at birth was between 30.3 and 35.0 cm TL and mass at birth between 276 and 325 g. The two ovaries and the two uteri were functional. Ripe ovarian follicles ready to be ovulated ranged between 76 and 85 mm in diameter and weighed between 200 and 237.6 g. Gestation lasted one year approximately, but ovarian follicles growth blocked at the beginning of gestation. However, ovarian follicles growth started again before embryos were at mid-term gestation. This is a new case of semi-delayed vitellogenesis typical of Squatina spp. A biannual reproductive cycle remains a suitable hypothesis. A calculated chemical balance of development based on dry masses of ripe follicles and full-term embryos was # 0.66 and showed that S. aculeata is a purely lecithotrophic species as other studied squatinid species. Ovarian fecundity ranged from 12 to 22 and is higher than uterine fecundity, which ranged from 8 to 12. Both categories of fecundity were slightly related with females size. The sex-ratio was 1: 1 in embryos. The subadult males significantly outnumbered the female ones. This was not the case for juveniles, adults and for the total sample.

The Atlantic weasel shark, Paragaleus pectoralis (Garman, 1906), is the only species of the genus Paragaleus to be recorded off the western coast of Africa. It is commonly landed at the fishing sites along the Senegalese coast. Adult males and females are mostly captured in spring and summer. The smallest male and female adults were 810 mm and 900 mm total length (TL), respectively. The largest male and the largest female adults were 1.32 m and 1.38 m TL, respectively, and weighed 7.55 kg and 11 kg, respectively. There was no significant difference for total mass and TL relationship between males and females. Mating occurred from March to May, and parturition in May and June. Gestation lasted approximately one year. Females had biennial or triennial reproductive cycle. Vitellogenesis did not occur while females were pregnant. Diameter of the largest yolky oocytes ranged from 25 to 31 mm (mean: 28.6 ± 2.6) and their mass from 8.8 to 9.9 g (mean: 9.4 ± 0.5). Both uteri were compartmentalized into chambers, with a single embryo in each chamber. Size and mass at birth, based on near-term embryos were between 390-500 mm TL and 214-407 g, respectively. A chemical balance of development based on mean dry masses of the largest yolky oocytes and the fully developed embryos was 14.8. Ovarian fecundity was slightly higher than uterine fecundity. There was a slight positive correlation between uterine fecundity and female TL, not between ovarian fecundity and female TL. Litter sizes ranged from two to seven (mean: 4.6 ± 1.6) with males outnumbering females.

The blacktip shark, Carcharhinus limbatus, is commonly captured along the west coast of Africa and rarely in the Mediterranean, where it was recorded in the Gulf of Gabès (southern Tunisia). Following competition pressure from its sympatric species, the sandbar shark, C. plumbeus and the spinner shark, C. brevipinna, it migrated northward into the Gulf of Tunis and off the Algerian coast. Adult males and females reached over 167 cm and 178 cm total length (TL), respectively. The largest male and the largest female were 216 cm and 245 cm TL, respectively. They were no significant differences of relationship of mass versus TL between males and females. C. limbatus is a placental viviparous elasmobranch. Adult females had a single ovary and two functional uteri, in which encapsulated eggs and embryos were not equally distributed. Mating occurred in Spring or in early Summer, with parturition in July. Gestation lasted approximately one year. There is perhaps a biannual reproductive cycle. In some specimens, vitellogenesis proceeded in parallel with gestation. Diameter of the largest yellow yolked oocytes ranged from 23 to 25 mm (mean: 23.95 ± 0.80) and their mass from 5.9 to 8.4 g (mean: 7.48 ± 0.92). Both uteri were compartmentalised into chambers and a single embryo developed in each chamber. Size and mass at birth, based on fully developed embryos, and the smallest free-swimming specimens (neonates) were between 61-65 cm TL and 0.935-1.375 kg respectively. A chemical balance of development based on mean dry masses of the largest yellow yolked oocytes and the fully developed embryos was # 69. It was the highest value ever computed in a viviparous elasmobranch, and confirmed that C. limbatus is a matrotrophic species. Ovarian fecundity was slightly higher than uterine fecundity. There was a slight relationship between the two categories of fecundity and the females TL. Litter sizes ranged from 6 to 8. Among the embryos and the free-swimming specimens the females outnumbered the males ones. This was not the case for the adults.