Stock structure analysis of ‘Aristeus alcocki Ramadan, 1938 (Decapoda: Aristeidae)’ in the Indian coast with truss network morphometrics

Abstract

The Arabian red shrimp (Aristeus alcocki Ramadan, 1938) is a deep-sea penaeoid shrimp that forms a major commercial fishery in the Indian coast. However, the spawning population of this species along the Indian coast is poorly known. To study this, stock structure of A. alcocki using truss morphometry was employed. A total of 1842 matured specimens were collected from five geographical locations (Tuticorin (SET), Chennai (SEC), Nagapattianam (SEN), Sakthikulangara (SWS), and Kalamuku (SWK)) along the Indian coast. Thirty-nine truss distances were extracted from each specimen and analyzed by multivariate methods (i.e., principal component analysis (PCA), discriminant functions (DF), and hierarchical cluster analysis). The results of the PCA indicated that the first two components cumulatively explained >70% (female: 72.1%; male: 71.5%) of the total morphometric variation. Stepwise DF analysis indicated that abdominal variables significantly discriminated the populations at different locations. The results clustered the five samples into a minimum of two groups: samples from SWK clustered in group I, whereas rest of the samples clustered in group II. Morphometric variation between the groups was significant for each sex. Significant differences between the groups may be attributed to geographical and environmental conditions, suggesting separate management strategies for resource sustainability.