C. Capapé

Production, maturity, reproductive cycle and fecundity of small-spotted catshark, Scyliorhinus canicula (Chondrichthyes: Scyliorhinidae) from the northern coast of Tunisia (Central Mediterranean)

Small-spotted catshark Scyliorhinus canicula (Linnaeus, 1758) is confronted since 2000 to a drastic decline of captures in Tunisian northern areas where it formerly was quantitatively and qualitatively very abundant. A study conducted in the area showed that males and females sexually matured between 400–478 mm and 364–471 mm total length (TL), respectively. The largest male and female were 521 mm and 531 mm TL, respectively and weighed 449 and 445.5 g, respectively. There was a not significant relationship total mass vs. TL between males and females. Conversely, the relationship of liver mass vs. TL significantly differed between sexes. Both HSI and GSI values did not present significant differences between males and females. There was a not significant relationship total mass vs. TL between males and females. Both male and female HSI reached high values in adults, significantly higher than those of sub-adults. Both male and female GSI values increased with TL of specimens; additionally, they showed significant differences between juveniles and sub-adults and also between sub-adults and adults. The OSI values were significantly different between juvenile and sub-adult females, and also between sub-adult and adult females. Monthly mean values of adult male and female HSI did not significantly vary throughout the year. Significant monthly changes were recorded in mean values of adult male however no significant changes were observed in monthly mean of GSI and OSI for adult females. Vitellogenic activity and production of egg cases permanently occurred throughout the year. The diameter of largest yolky oocytes ranged from 20.1 to 23.0 (mean = 21.43 ± 1.07) and weighed from 0.64 to 0.90 g (mean = 0.78 ± 0.09). Some measurements were taken on egg cases: length with horns ranged 42.5-55.7 mm with mean = 48.9 ± 2.9, width ranged 13.6–19.7 mm with mean = 16.50 ± 0.9, while the total mass of complete egg case ranged between 1.8 and 4.6 g, with mean = 2.4 ± 0.4. An annual fecundity estimation based on production of egg cases and oocytes during one year counted in adult females, enabled us to consider it between 40 and 240.

A CASE OF HERMAPHRODITISM IN TORTONESE'S STINGRAY, DASYATIS TORTONESEI (ELASMOBRANCHII: RAJIFORMES: DASYATIDAE) FROM THE LAGOON OF BIZERTE, TUNISIA

A normal hermaphrodite Tortoneses stingray, Dasyatis tortonesei Capape, 1975, captured in the brackish L agoon of Bizerte (north-eastern Tunisia) is described in this note. It was a large specimen measuring 685 mm total length, 350 mm disk width, and 2190 g of the total body mass. The specimen externally presented medial cuspidate tooth rows on both jaws, and two claspers were present, that were rigid and calcified although shorter than those observed in normal specimens. The dissection of the abdominal cavity revealed on each side, an ovary normally developed that contained y olked oocytes, a complete genital tract and an uterus less developed than in normal adult. Conversely the testes were rudimentary, both Leydigs glands were developed and a com- plete, slightly convoluted, male duct existed on the left side only. In all, 13 cases of normal (4) and abnormal (9) hermaphroditism, including the Tunisian D. tortonesei, have been found in batoid species, to date, confirming that the phenomenon is very rare among these chondrichthyan fishes.. K eywords: Dasyatis tortonesei, normal hermaphrodite, Lagoon of Bizerte, Tunisia, central Mediterranean

First record of the west African goatfish, Pseudupeneus prayensis (Actinopterygii: Perciformes: Mullidae), off the Tunisian coast (central Mediterranean)

Two specimens of the west African goatfish, Pseudupeneus prayensis (Cuvier, 1829), were found for the first time off the Tunisian coast, in northern area. They constituted the third Mediterranean record of this fish. Both specimens were studied and described, and some biological observations were reported. Same taxonomic charac- ters were concomitantly determined on two west African goatfish caught off the coast of Senegal, for comparison. The occurrence of Pseudupeneus prayensis in the area and the Mediterranean Sea is discussed and commented.

First records of barracudina Sudis hyalina (Osteichthyes: Paralepididae) off the Syrian coast (eastern Mediterranean)

Records of 9 barracudinas Sudis hyalina Rafinesque, 1810 off the Syrian coast are reported in this note, constituting the first records in the area and confirming the eastern extension range of the species in the Mediterranean. The occurrence of the species is commented and discussed, in the region where a sustainable population is probably established.

First case of albinism recorded in striped panray Zanobatus schoenleinii (Chondrichthyes: Platyrhinidae) from the coast of Senegal (eastern tropical Atlantic)

This paper gives the description of a striped panray Zanobatus schoenleinii (Müller and Henle, 1841) presenting the first case of albinism recorded in this species. The specimen was an adult male captured at low depth off the coast of Senegal (eastern tropical Atlantic). Comments on albinism in fishes are provided in this paper, especially all cases reported in batoid species.

FOOD AND FEEDING HABITS OF THE RED MULLET, MULLUS BARBATUS (ACTINOPTERYGII: PERCIFORMES: MULLIDAE), OFF THE NORTHERN TUNISIAN COAST (CENTRAL MEDITERRANEAN)

Of the three mullid species recorded to date in Tunisian waters, two are commonly recorded the red mullet, Mullus barbatus L., and the surmullet (or striped red mullet), M. surmuletus L. (see Bradai et al. 2004). Both species are abundantly captured throughout the year; the mean production reached 4434.7 t between 2004 and 2008 (Anonymous 2008). The third species is the Por’s goatfish, Upeneus pori Ben-Tuvia et Golani, 1989, one the Lessepsian migrant fish species, considered as successfully established in the eastern Mediterranean Sea (Golani et al. 2002). This latter species was firstly found in southern Tunisia by Ben Souissi et al. (2005), then, it migrated toward northern area, and was recorded in the brackish Lagoon of Bizerte by Azzouz et al. (2010). A second alien species was recorded only recently; it was identified as a specimen of the west African goatfish, Pseudupeneus prayensis (Cuvier, 1829), according to Azzouz et al. (2011). Food and feeding habits of Mullus barbatus formed the object of several studies conducted from specimens ACTA ICHTHYOLOGICA ET PISCATORIA (2011) 41 (2): 109–116 DOI: 10.3750/AIP2011.41.2.06

Food and feeding habits of black scorpionfish, Scorpaena porcus (Osteichthyes: Scorpaenidae) from the northern coast of Tunisia (Central Mediterranean)

Food and feeding habits of black scorpionfish Scorpaena porcus Linnaeus, 1758 were carried out from 715 specimens collected off Ras Jebel, city located in northern Tunisia. Diet was studied in relation to fish size, sexes and seasons. The relationship total length (TL) versus total body mass (TBM) showed a positive allometry, suggesting that S. porcus found favourable environmental parameters and available preys in its habitat. Vacuity index (VI) values were high for the total sample and also related to size classes, sexes, and seasons. Stomach contents of S. porcus revealed a very large diversity of preys; a total of 79 taxa were recorded, 3 osteichthyan, 69 crustacean, 2 annelid and 2 gastropod species, while angiosperma, alga, were rare. Crustaceans were the most abundantly found followed by osteichthyes. The troph value of S. porcus from the north-eastern coast of Tunisian reached 3.48 ± 0.58. S. porcus did not display significant changes in the diet related to sizes and/or seasons. S. porcus should be included among the carnivorous species which play a major role in regulation of marine food webs.

First record of nakedband gaper Champsodon nudivittis (Osteichthyes: Champsodontidae) off the Syrian Coast (Eastern Mediterranean)

This paper reports the first record of nakedband gaper Champsodon nudivittis from the Syrian coast. This record confirms the occurrence of the species in the Levant Basin and its eastern extension range in he Mediterranean Sea. Additionally, this additional capture of C. nudivittis in the eastern Mediterranean supports that a sustainable population is at present probably established in the same Mediterranean region.

First record of Red Sea goatfish Parupeneus forsskali (Osteichthyes: Mullidae) from the Syrian coast (Eastern Mediterranean)

This paper reports the first record of Red Sea goatfish Parupeneus forsskali (Fourmanoir and Guézé, 1976) from the Syrian coast. This record confirms the occurrence of the species in the Levant Basin. However, no sufficient data were carried out to date to support that a population is at present substantially established in the same area.

Maturity, reproductive cycle and fecundity of common torpedo, Torpedo torpedo (Chondrichthyes, Torpedinidae) from the Lagoon of Bizerte (Northeastern Tunisia, central Mediterranean)

Common torpedo Torpedo torpedo (Linnaeus, 1758) is widely distributed in the Mediterranean Sea, especially in southern and northern regions. The species is known throughout the Tunisian coast and entered brackish areas, such as the northeastern Lagoon of Bizerte, where it is commonly captured. Investigations conducted in this latter area showed that males and females sexually matured between 234–285 mm and 245–280 mm total length (TL), respectively. The largest male and female were 403 mm and 435 mm TL, respectively and weighed 721.5 and 1273.5 g, respectively. There was a not significant relationship total mass versus TL between males and females. Conversely, the relationship of liver mass versus TL significantly differed between sexes. The diameter of the largest yolky oocytes ranged between 43 and 47 mm (mean 45.08 ± 0.98)}, while the mass ranged between 29.5 and 37.4 g (mean 31.79 ± 2.20). Near term embryos ranged from 19.34 to 31.28 mm TL (mean: 24.60 ± 4.12) and weighed from 3.9 to 9.0 g (mean 5.97 ± 1.41). Ovarian fecundity ranged from 4 to 36 (mean = 11.60 ± 5.96). Uterine fecundity or litter size ranged from 3 to 13 (mean = 6.36 ± 2.67). Both fecundities showed a positive relationship with TL of females. A chemical balance of development based on mean dry masses of yolky oocytes and near-term embryos was 0.75 and suggested that T. torpedo could be considered as a pure lecithotrophic species. Hepatosomatic index (HSI) and gonadosomatic index (GSI) calculated for females presented significant higher values than those of males. HSI values of males significantly differed differences between juveniles, sub-adults and adults, and in females, HSI values were not significantly different between juveniles and sub-adults and significantly different between sub-adults and adults. The values of male GSI increased with TL of specimens; additionally, they showed significant differences between juveniles and subadults, but not between sub-adults and adults. Monthly mean values of adult male and female HSI significantly varied throughout the year. Monthly mean of females GSI showed significant changes especially from January to April, due to a high vitellogenic activity, GSI decreased from May to August, during this period all yolky oocytes were ovulated, then GSI increased progressively from September. The reproductive cycle lasted one year approximately and gestation period 4 months, while near-term females were captured in August. Vitellogenesis did not proceed in parallel with embryonic development: during ovarian vitellogenic activity, the uteri were empty and in an appearent resting phase, conversely during gestation, the ovaries did not exhibit an appearent activity, by contrast other specimens exhibited a vitellogenic activity during gestation. With special regard to the latter case, it remains difficult to state if these small yolky oocytes were not ovulated, or if they were new oocytes produced immediately after ovulation, both hypothesis remaining suitable.