Nuengruetai Yoknoi, Jes Kettratad, Nittharatana Paphavasit, and Prasert Tongnunui

DOI: 10.14456/sjst-psu.2017.32

pp. 293 - 301

Abstract

This study aimed to describe development patterns and define length at juvenile of two co-occurring terapontid
fishes. Terapon jarbua (n=366, 1.49-48.24 mm) and Pelates quadrilineatus (n=314, 1.64-54.13 mm) were collected from coastal
area, Trang Province, Thailand. Specimens were divided into five developmental stages: preflexion larvae, flexion larvae,
postflexion larvae, transforming larvae, and juvenile by study of morphometric character, meristic character and pigmentation
pattern. The length at juvenile was defined by using a multivariate analysis of morphometric characters. The length at juvenile
stage of T. jarbua and P. quadrilineatus began at 23.16 mm and 18.24 mm in standard length, respectively. All morphometric
characters were significantly different (P<0.05) between transforming larvae and juvenile stage in both species. An understanding in development patterns can aid in the explanation of their ontogenetic niche shifts. Due to the actual timing of
switches in diet and habitat, it usually relates to changes in morphology of fish. The increase of mouth and jaw were significant in the ontogenetic dietary shift. The increase of body depth, fin length and eye size were also important to the mobile
ability and feeding habitat shift in terapontid fishes.