Have a personal or library account? Click to login
Seasonal changes in the reproductive cycle and condition index of the surf clam Mactra stultorum (Mollusca: Bivalvia) in the Gulf of Gabes, Tunisia Cover

Seasonal changes in the reproductive cycle and condition index of the surf clam Mactra stultorum (Mollusca: Bivalvia) in the Gulf of Gabes, Tunisia

Oceanological and Hydrobiological Studies
Volume 52 (2023): Issue 3 (September 2023)
By: Abdelkarim Derbali  
Open Access
|Oct 2023

Figures & Tables

Figure 1

Map of the study area. The location of sampling transects is indicated
Map of the study area. The location of sampling transects is indicated

Figure 2

Mactra stultorum: Variation of sexual proportion (%) and sex ratio (F:M) according to individuals size (SL, 6 mm classes). The dotted line illustrates an unbiased sexual proportion (F:M = 1:1). * Size classes with unbalanced sex ratio (χ2test, p < 0.05).
Mactra stultorum: Variation of sexual proportion (%) and sex ratio (F:M) according to individuals size (SL, 6 mm classes). The dotted line illustrates an unbiased sexual proportion (F:M = 1:1). * Size classes with unbalanced sex ratio (χ2test, p < 0.05).

Figure 3

Mactra stultorum: Relationship between percentage of mature individuals and total shell length
Mactra stultorum: Relationship between percentage of mature individuals and total shell length

Figure 4

Mactra stultorum: Monthly variations in water temperature and salinity recorded during the study period (2017) in the Skhira region (south of Tunisia)
Mactra stultorum: Monthly variations in water temperature and salinity recorded during the study period (2017) in the Skhira region (south of Tunisia)

Figure 5

Mactra stultorum: Monthly variations in the condition index A (supplemented with data for shell length) and B, and tissue weight rate as percentage of total weight (C) in the Gulf of Gabes (Tunisia). Values expressed as mean ± IC. The number of females and males are 477 and 462, respectively.
Mactra stultorum: Monthly variations in the condition index A (supplemented with data for shell length) and B, and tissue weight rate as percentage of total weight (C) in the Gulf of Gabes (Tunisia). Values expressed as mean ± IC. The number of females and males are 477 and 462, respectively.

Figure 6

Mactra stultorum: Relationship between the monthly frequency distribution of gonadal development stages in females (A) and males (B) during the study period (2017)
Mactra stultorum: Relationship between the monthly frequency distribution of gonadal development stages in females (A) and males (B) during the study period (2017)

Mactra stultorum_ Size at first maturity corresponding to being 25, 50 and 75% mature (L25, L50 and L75) in the Gulf of Gabes (Tunisia)

ParametersMalesFemalesCombined sexes
a0.9871.1381.025
R2 (correlation)0.9930.9970.998
L50 (mm)20.43 ± 0.1922.10 ± 0.1321.28 ± 0.11
L25 (mm)19.3221.1320.21
L75 (mm)21.5423.0722.35
DOI: https://doi.org/10.26881/oahs-2023.3.01 | Journal eISSN: 1897-3191 | Journal ISSN: 1730-413X
Journal RSS Feed
Language: English
Page range: 264 - 272
Submitted on: Apr 12, 2023
Accepted on: Jun 2, 2023
Published on: Oct 9, 2023
Published by: University of Gdańsk
In partnership with: Paradigm Publishing Services
Publication frequency: 4 issues per year
Keywords:
reproductive cycle,
sex ratio,
size at maturity,
condition index,
Gulf of Gabes,
Tunisia
Related subjects:
Chemistry,
Chemistry, other,
Geosciences,
Geosciences, other,
Life sciences,
Life sciences, other

© 2023 Abdelkarim Derbali, published by University of Gdańsk
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Volume 52 (2023): Issue 3 (September 2023)Next article