Morphometric Relationship of Otolith With Body Length and Weight of Bonylip Barb (Osteochilus Vittatus Valenciennes, 1842) in The Rivers of Magelang Regency

Abstract

The bonylip barb (Osteochilus vittatus) is a freshwater fish species commonly found in the rivers of Magelang Regency and is captured by the fishermen as a source of protein. The purpose of this study is to determine the relationship between the morphometric and the somatic body size of the bonylip barb. Samples were collected from the catch of fishermen in the river waters of Magelang Regency from September to December 2025. The total number of fish samples used in this study was 105 individuals (62 male fish and 43 female fish). The fish body was measured for length and weight, then dissected, and the otolith was removed for otolith morphometric measurements (otolith length, width, area, perimeter, and mass). Morphometric parameters of otoliths were measured using ImageJ, and otoliths were weighed on an analytical balance. The results of the otolith shape index analysis of bonylip barb, based on otolith morphometrics, indicate that oval-shaped otoliths tend to be elongated and irregularly surfaced. The relationships between male and female otoliths and between right and left otoliths were tested separately using t-tests. Statistical analysis of otoliths by gender showed no significant differences in length, width, or area, whereas circumference and weight differed significantly. The statistical test of the right and left otoliths showed no significant differences in any otolith parameters, indicating that the otoliths are symmetrical. The relationship between the length and weight of the bony lip barb is reflected in the linear regression equation y(i) = a + bx. The analysis results show a positive relationship between fish somatic size and otolith size, indicating that the otolith can serve as an indicator of fish growth.