Morphometric Distribution of Java Eel Anguilla sp. Caught from Different Estuaries of Central Java

Abstract Morphometric analysis is one of the procedures that can be used for identifying organism species. Determination of the long and shortfin eel (Anguilla sp.) is usually based on the specific measurements of the dorsal and anal fin. This study aims to evaluate a variety of pre-dorsal (PD/TL %), pre-anal (PA/TL %), and ano-dorsal ratio (AD %) in the different eel size classes and variation of sizes among Central Java estuaries. Samples (148 eels) were taken from riverine, marshes, and impounding seawater of Central Java estuaries in July 2019. The results show that the widest ranges of PD/TL, PA/TL, and AD ratios (%) were 12.98 – 48.18 %, 19.03 – 50.78 %, and -6.56 to 32.88 %, respectively, which were found in Gatel riverine of Nusawungu. Those values overlap with the species of Anguilla interioris, A. megastoma, A. nebulosa nebulosa, A. labiata, A. marmorata, A. bicolor bicolor, and even A. b. pacifica. Percentage value in a certain ranges of A-D were dominated by 0 - 3.6 % (96.3 %) and 14.1 – 19.3 % (3.7 %). This can be concluded that during the months of July, the short-fin eel (known as A. b. bicolor) had been dominated to be caught from Southern Central Java Estuaries than a long-fin eel.