Floristic diversity and vegetation patterns along disturbance gradient in arid coasts in southern Mediterranean: Case of the Gulf of Gabès, southern Tunisia

Age, growth and reproductive parameters were estimated for Raja radula from the Gulf of Gabes (southern Tunisia, central Mediterranean Sea), collected monthly during 2007 from commercial fisheries. In total, 550 females (18.5–80.0 cm TL) and 400 males (13.4–65 cm TL) were examined to study the reproductive cycle. A subsample of 272 specimens (140 females and 132 males, ranging from 15.5 to 80 cm in total length, TL) was used for age and growth estimation derived from vertebral centra. The marginal-increment and edge analysis showed annual deposition of growth bands. The oldest female in the study was 12 years old and 80 cm in TL, whereas the oldest male was 9 years old and 65 cm in TL. The von Bertalanffy growth parameters were L∞ = 76.36 cm, K = 0.22 year–1 and t0 = –0.16 years for males. There was no significant difference in growth between the sexes. The size-at-maturity was 47.05 cm for males and 56.48 cm for females. The age-at-maturity was estimated to be 4.47 and 5.89 years, respectively, for males and females. There was no significant difference of size- and age-at-maturity between the sexes. Females carrying egg cases occurred throughout the year. Variations in the gonadosomatic and hepatosomatic indices showed a continuous reproductive cycle throughout the year.

Download Full-text

Reproductive cycle and size at first sexual maturity ofHexaplex trunculus(Gastropoda: Muricidae) in the Gulf of Gabès (southern Tunisia)

Invertebrate Reproduction & Development ◽

10.1080/07924259.2010.9652335 ◽

2010 ◽

Vol 54 (4) ◽

pp. 213-225 ◽

Cited By ~ 15

Author(s):

KAMEL ELHASNI ◽

MOHAMED GHORBEL ◽

PAULO VASCONCELOS ◽

OTHMAN JARBOUI

Keyword(s):

Reproductive Cycle ◽

Sexual Maturity ◽

Gulf Of Gabes ◽

Gulf Of Gabès ◽

Southern Tunisia

Download Full-text

Hypocreadium caputvadum sp. nov. (Digenea, Lepocreadiidae), an intestinal parasite of the grey triggerfish, Balistes capriscus (Teleostei, Balistidae) from the Gulf of Gabès, Mediterranean Sea

Acta Parasitologica ◽

10.2478/s11686-011-0060-8 ◽

2011 ◽

Vol 56 (3) ◽

Cited By ~ 1

Author(s):

Hichem Kacem ◽

Hela Derbel ◽

Lassâd Neifar

Keyword(s):

New Species ◽

Mediterranean Sea ◽

Intestinal Parasite ◽

Gulf Of Gabes ◽

Gulf Of Gabès ◽

Balistes Capriscus ◽

Southern Mediterranean

AbstractHypocreadium caputvadum sp. nov. (Digenea, Lepocreadiidae) is described from the intestine of Balistes capriscus Gmelin collected from the Gulf of Gabès (Tunisia) in the southern Mediterranean Sea. This new species can be distinguished by a combination of characteristics shared by no other described species of Hypocreadium Ozaki, 1936. These characteristics include the presence of a distinct anterior notch, the follicular vitellarium confluent in the forebody, the presence of a muscular sphincter at the level of the anterior third of the metraterm and the size and the position of the cirrus-sac.

Download Full-text