Comparative morphological descriptions of interior shell patterns of the Venerid bivalves: Meretrix lyrata, Mercenaria mercenaria and Venerupis philippinarum using Landmark-based Geometric Morphometric Analysis

• Published in: Aquaculture, Aquarium, Conservation & Legislation Vol. 7; no. 5; pp. 386 - 395
• Main Authors: Moneva, Carlo Stephen O, Baquiano, Paolo Miguel L, Blasco, Julito O, Borlaza, Kaia Marie E, Burias, Dan Matthew E, Flores, Kimberly A, Fuentes, Gleda Russelle E, Pancho, Annalyn Grace E, Sanchez, Rafael Ryno G
• Format: Journal Article
• Language: English
• Published: Cluj-Napoca Bioflux SRL 12.10.2014
• Subjects: Adaptation; Animal morphology; Aquaculture; Biodiversity; Biology; Bivalvia; Clams; Clustering; Colour; Ecological monitoring; Ecology; Evolution & development; Landmarks; Lesions; Mathematical morphology; Mercenaria mercenaria; Meretrix lyrata; Mollusks; Morphology; Morphometry; Multivariate analysis; Muscles; Orientation; Paleontology; Phenotypic variation; Phenotypic variations; Shells; Species; Studies; Tapes philippinarum; Variance analysis; Veneridae; Venerupis; Venerupis philippinarum; British Columbia Canada; Canada; Southeast Asia; Japan; Philippines
• ISSN: 1844-8143; 1844-9166

The shell is the most distinct feature of bivalves, which exhibits a large degree of variation in terms of morphology. Recognition of bivalve variability is important for the effective culture of these organisms. Traditional approach has been made to study shell morphology using differences in length and color. However, conventional methodology can be strengthened by applying additional quantitative tools. A more recent and advanced approach in investigating morphological shell shape patterns were incorporated in the present study. Using Geometric Morphometric (GM) Analysis, the right and left valve interiors of the three species of bivalves from family Veneridae - Lyrate asian hard clam (Meretrix lyrata), Quahog or little neck (Mercenaria mercenaria), and Manila clam (Venerupis philippinarum) from Tubod, Lanao del Norte, Philippines were explored for phenotypic variations. Fifteen (15) anatomical landmark test was performed - covering characteristics of the umbo, hinge, muscle scars, pallial line and pallial sinus. Multivariate Analysis of Variance (MANOVA)/Canonical Variance Analysis (CVA) scatter plot was used to graphically present the clustering of each species. Moreover, Relative Warp Analysis (RWA) and Kruskal-Wallis Test, was used to obtain consensus morphology of the three species and their variations along the negative and positive axes, and to test if there are significant differences on the anatomical landmark of the three species, respectively. Results in MANOVA yielded significant differences in the three species, CVA showed a distinct clustering of species population, and Kruskal-Wallis supported this clustering by obtaining significant results. The analyses showed that the umbo position, orientation of the muscle scar, relative deepness of the pallial sinus, and pallial line length are significantly different in M. lyrata, M. mercenaria and V. philippinarum. The morphological differences on their anatomical landmarks are consequences adaptation to their specific environmental preferences. The results of the present study can provide more information about the ecology and characteristics of the three species and use this information to devise techniques that can manipulate production yield without the expense of the life of other animals and the whole biodiversity.