Shell morphology, morphometric relationships and relative growth of three topshell species (Gastropoda: Trochidae) from the Algarve coast (Southern Portugal)
Vasconcelos, P.; Santos, A.C.N.; Pereira, F.; Moura, P.; Carvalho, A.N.; Gaspar, M.B. (2022). Shell morphology, morphometric relationships and relative growth of three topshell species (Gastropoda: Trochidae) from the Algarve coast (Southern Portugal). Thalassas 38(1): 665-674. https://dx.doi.org/10.1007/s41208-021-00351-y
In: Thalassas. Universidad de Vigo: Vigo. ISSN 0212-5919; e-ISSN 2366-1674, more
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| Keywords |
Phorcus lineatus (da Costa, 1778) [WoRMS]; Phorcus sauciatus (F. C. L. Koch, 1845) [WoRMS]; Steromphala umbilicalis (da Costa, 1778) [WoRMS]
Marine/Coastal |
| Author keywords |
Phorcus lineatus; Phorcus sauciatus; Steromphala umbilicalis; Shell shape; Isometry; Allometry |
| Authors | | Top |
- Vasconcelos, P.
- Santos, A.C.N.
- Pereira, F.
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- Moura, P.
- Carvalho, A.N.
- Gaspar, M.B.
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| Abstract |
This study analysed the shell morphology, morphometric relationships and relative growth in three topshell species (Phorcus lineatus, Phorcus sauciatus and Steromphala umbilicalis) collected in the Algarve coast (southern Portugal). A total of 1382 individuals were sampled (465 P. lineatus, 447 P. sauciatus and 470 S. umbilicalis) and all species comprised individuals with broad size and weight ranges. Morphometric relationships were established between linear (shell height, width, spire height, aperture height, aperture width) and ponderal (total weight) variables, whose relative growth (isometry vs. allometry) was analysed to assess variation throughout the species ontogeny. All morphometric relationships were highly significant (P < 0.001) and displayed invariably high correlation coefficients (r = 0.828 to 0.977), presenting mostly negative allometries (77.8%), distantly followed by positive allometries (16.7%) and by isometric growth (5.5%). In addition, four morphometric indices (sphericity, conicity, aperture roundness and density) were calculated to further describe and discern variation in shell shape in these topshell species. Moreover, this study provides a useful compilation and comparison of morphometric relationships, indices and relative growth features, thus improving the knowledge currently available on these subjects for P. lineatus, P. sauciatus and S. umbilicalis. |
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