Community Structure of Terrestrial Invertebrates Inhabiting a Tidal Marsh Islet in the Mediterranean Sea (Gulf of Gabes, Tunisia)

The Gulf of Gabès on the southern coasts of Tunisia in the central part of the Mediterranean is a very shallow basin, characterized by semidiurnal tides, attaining a range of 2.3 m during spring tides. The intertidal zone was covered by extended Zostera (Zosterella) noltei Hornemann, 1832 beds mainly developed around the Kneiss Islands while tidal channels ensured the water circulation in this sub-tropical environment with very low freshwater input and high summer temperature. In spite of protected conventions, the area remained under high human pressures: overfishing, and the impact of the pollution of the phosphate industry. Intensive sampling in both intertidal and shallow subtidal zones during annual cycles permitted to identify a rich macrofauna which increase considerably the species known in this eastern part of the Mediterranean Sea. More than 50 species are added for the Tunisian fauna. Moreover, patterns of diversity are analysed with the sediment types, presence or absence of Zostera noltei seagrass bed, and human pressures. The list of the collected species are compared with those of surrounding areas in both Western and Eastern Mediterranean Sea.

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Allopodocotyle tunisiensis sp. nov. (Digenea, Opecoelidae), a parasite of Solea aegyptiaca (Teleostei, Soleidae) off Tunisia

Acta Parasitologica ◽

10.2478/s11686-009-0054-y ◽

2009 ◽

Vol 54 (4) ◽

Cited By ~ 3

Author(s):

Hela Derbel ◽

Lassad Neifar

Keyword(s):

New Species ◽

Mediterranean Sea ◽

Seminal Vesicle ◽

Ventral Sucker ◽

Anterior Margin ◽

Gulf Of Gabes ◽

Gulf Of Gabès ◽

The Status ◽

The Mediterranean

AbstractAllopodocotyle tunisiensis sp. nov. is described from the intestine of Solea aegyptiaca Chabanaud collected from the Gulf of Gabès in the Mediterranean Sea off Tunisia. The new species belongs to the group C of Allopodocotyle Pritchard, 1966 species (sensu Bray 1987). It differs from its congeners in this group by the shape of the seminal vesicle and the anterior extend of the vitellarium which varies between just posterior to the ventral sucker and anterior margin. A key to the Allopodocotyle species of group C is presented. The status of the genera Allopodocotyle and Macvicaria (Gibson and Bray 1982) are briefly discussed.

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Distribution and Morphometric Characters of the Mediterranean Brown Ray, Raja Miraletus (Chondrichthyes: Rajidae) in the Gulf of Gabes (Tunisia, Central Mediterranean)

American Journal of Agriculture and Forestry ◽

10.11648/j.ajaf.20140202.15 ◽

2014 ◽

Vol 2 (2) ◽

pp. 45 ◽

Cited By ~ 1

Author(s):

Hasna Kadri

Keyword(s):

Central Mediterranean ◽

Gulf Of Gabes ◽

Morphometric Characters ◽

Gulf Of Gabès ◽

The Mediterranean

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High diversified benthic habitats in a tidal Mediterranean sub-tropical environment: the case of the Gulf of Gabès (Tunisia)

10.7287/peerj.preprints.26537v1 ◽

2018 ◽

Author(s):

Abir Fersi ◽

Nawfel Mosbahi ◽

Ali Bakalem ◽

Jean-Philippe Pezy ◽

Alexandrine Baffreau ◽

...

Keyword(s):

Mediterranean Sea ◽

Eastern Mediterranean ◽

Tropical Environment ◽

Gulf Of Gabes ◽

Annual Cycles ◽

Gulf Of Gabès ◽

Zostera Noltei ◽

Sediment Types ◽

The Mediterranean ◽

The Impact

The Gulf of Gabès on the southern coasts of Tunisia in the central part of the Mediterranean is a very shallow basin, characterized by semidiurnal tides, attaining a range of 2.3 m during spring tides. The intertidal zone was covered by extended Zostera (Zosterella) noltei Hornemann, 1832 beds mainly developed around the Kneiss Islands while tidal channels ensured the water circulation in this sub-tropical environment with very low freshwater input and high summer temperature. In spite of protected conventions, the area remained under high human pressures: overfishing, and the impact of the pollution of the phosphate industry. Intensive sampling in both intertidal and shallow subtidal zones during annual cycles permitted to identify a rich macrofauna which increase considerably the species known in this eastern part of the Mediterranean Sea. More than 50 species are added for the Tunisian fauna. Moreover, patterns of diversity are analysed with the sediment types, presence or absence of Zostera noltei seagrass bed, and human pressures. The list of the collected species are compared with those of surrounding areas in both Western and Eastern Mediterranean Sea.

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Allometry, condition factor and growth of the swimming blue crab Portunus segnis in the Gulf of Gabes, Southeastern Tunisia (Central Mediterranean)

Mediterranean Marine Science ◽

10.12681/mms.14515 ◽

2019 ◽

Vol 20 (3) ◽

pp. 566

Author(s):

OLFA BEN ABDALLAH-BEN HADJ HAMIDA ◽

NADER BEN HADJ HAMIDA ◽

HOUDA CHAOUCH ◽

HECHMI MISSAOUI

Keyword(s):

Carapace Length ◽

Condition Factor ◽

Growth Parameters ◽

Carapace Width ◽

Central Mediterranean ◽

Gulf Of Gabes ◽

Gulf Of Gabès ◽

Significant Difference ◽

The Mediterranean ◽

Portunus Segnis

The blue swimming crab Portunus segnis (Forskål, 1775) is one of the earliest Lessepsian invaders of the Mediterranean Sea, and is recorded since decades in various areas of the Mediterranean. Its presence in the southeastern Tunisian coasts (Gulf of Gabes) is, however, very recent. Allometry, condition factor and growth of P. segnis were studied along the Gulf of Gabes coasts. Sampling was performed by artisanal fishing gears as well as trawl net during a one-year period (October 2015 to September 2016) as processed 4971 crabs were collected. The crab carapace width (CW) ranged from 45 to 168 mm for males and 50 to 159 mm for females. The crab carapace length (CL) was 22.02-89.20 mm and 38.70-85.28 mm, respectively for males and females. The carapace width-carapace length, carapace width- front, carapace width-carapace height and carapace width-weight relationships were studied in separate sexes of crab. The covariance analysis indicates a significant difference between the two sexes with respect to the carapace width-carapace length and the carapace width-weight relationships. The condition factor ranged between 0.0042 and 0.0118 with a mean of 0.0078. The condition factor decreased with increasing crab size. The Von Bertalanffy growth parameters CW∞, K and t0 were estimated on the basis of Length-frequency modal progression analysis methods. The mean values of L∞ (mm), K (year-1) and t0 would be, respectively, 206.48 mm, 1.34 and -0.130 for males; 183.89 mm, 1.42 and -0.127 for females and, 190.60 mm, 1.02 and -0.177 for combined sexes.

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Space-time variation of ciliates related to environmental factors in 15 nearshore stations of the Gulf of Gabes

Mediterranean Marine Science ◽

10.12681/mms.792 ◽

2014 ◽

Vol 16 (1) ◽

pp. 162 ◽

Cited By ~ 4

Author(s):

J. ELLOUMI ◽

Z. DRIRA ◽

A. HAMZA ◽

H. AYADI

Keyword(s):

New Records ◽

Longitudinal Distribution ◽

Biotic Factors ◽

Phytoplankton Abundance ◽

Gulf Of Gabes ◽

Size Classes ◽

Gulf Of Gabès ◽

Size Groups ◽

Abiotic And Biotic Factors ◽

High Diversity

Diversity and structure of ciliate communities in the Gulf of Gabes (Tunisia) were investigated based on a survey of 15 nearshore stations along 237 Km, by monthly sampling over a 1-year. Ciliated protozoa were identiﬁed to genus and/or species level and enumerated. Statistic tools were used to explain the ciliates assemblage. High ciliates species richness from 133 taxa was recorded, including new records of 76 species. This study showed a longitudinal distribution of ciliate communities, which are organized in northern stations (from Tabia to Harbor of Gabes) and southern stations (from Zarrat to Jabiat Haj Ali). The number of taxa increased significantly in northern stations but decreased in the southern. This distribution was mainly influenced by the salinity and phytoplankton abundance. Ciliate taxa were grouped into fives size-classes: 15-30 µm, 30-50 µm, 50-100 µm, 100-200 µm and >200 µm. In terms of abundance, most abundant size groups were small ciliates (15-30 μm) accounted from 15 to 79 %, while the greatest biomass contribution came from the 50-100 μm size classes. We thus conclude high diversity of ciliates communities that showed a geographical distribution influenced by abiotic and biotic factors along the coast of Gulf of Gabes.

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Amphipods from tidal channels of the Gulf of Gabès (central Mediterranean Sea)

Mediterranean Marine Science ◽

10.12681/mms.15913 ◽

2018 ◽

Cited By ~ 3

Author(s):

ABIR FERSI ◽

JEAN CLAUDE DAUVIN ◽

JEAN PHILIPPE PEZY ◽

LASSAD NEIFAR

Keyword(s):

Species Richness ◽

Mediterranean Sea ◽

Native Species ◽

High Energy ◽

Tidal Channels ◽

Central Mediterranean ◽

Gulf Of Gabes ◽

Seagrass Meadows ◽

Gulf Of Gabès ◽

The Mediterranean

The spatial and temporal species richness, abundance and assemblage structure of amphipods from four tidal channel of the Gulf of Gabès were studied at 26 stations and during four seasons from March 2016 to January 2017. This led to the identification of 4,278 individuals, 45 species and 21 families. The four mostly diversified families are the Ampeliscidae (6 species), the Caprellidae (5) and the Aoridae and Maeridae (4 species both), while three families account for ~ 75% of the individuals: Aoridae (45.5 %), Corophiidae (20.5%) and Dexaminidae (7.2%). The species richness and abundance were higher in winter than at other seasons. The fauna is dominated by a small number of species characteristic of areas with detritus accumulation and seagrass meadows, including Microdeutopus anomalus, Monocorophium acherusicum, Dexamine spinosa, Microdeutopus gryllotalpa, Cymadusa filosa and Elasmopus rapax, which are commonly recorded in lagoons and coastal shallow waters of the Mediterranean Sea. The amphipod structure is linked to the location of tidal channels in the Gulf of Gabès. Abundances are low in the Kerkennah channel compared with other channels, especially the Maltine channel with high winter accumulation of organic matter. There are also low abundances in high-energy hydrodynamic zones with gravel sediment; conversely, the presence of macrophytes, mainly in the seagrass meadows, increases amphipod diversity. As a result of this study, five new species can be added to the inventory of the Tunisian marine amphipod fauna, including a non-native species for the Mediterranean Sea, Paracaprella pusilla.

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