Molecular confirmation of the occurrence of Anguilla interioris (Actinopterygii: Anguilliformes) in North Maluku of Indonesia and mitochondrial DNA haplotype diversity among existing specimens

Nineteen species of Anguilla Schrank, 1798 are globally distributed in the world, however knowledge on the biogeography, species diversity and ecology of the 13 species of tropical anguillids in the Indo-Pacific region is highly limited. This study examined the diversity of tropical anguillids found in North Maluku of East Indonesia, which is known to have unique and highly heterogeneous habitats, complex oceanography, high biodiversity, and representativeness of Asian and Australian fauna. By means of molecular identification, two tropical anguillid eels, A. marmorata Quoy & Gaimard, 1824 and A. interioris Whitely, 1938, were confirmed to be distributed in North Maluku. This study also examined the mitochondrial DNA haplotype diversity of A. interioris, as it could contribute to our understanding of the biogeography and life history of this eel species. Our molecular analyses showed the presence of the same haplotypes along the different locations in the Indo-Pacific region. Although more samples and DNA markers are required to provide more support, the results suggest that the larvae of A. interioris from potentially different spawning sites in the Indian and Pacific oceans could be mixed together due to the complexity of oceanic currents, and when these migrating larvae reach maturity, they would likely spawn with the local eels.

First record of cannibalism in the giant mottled eel Anguilla marmorata (Actinopterygii: Anguilliformes) as revealed by DNA barcoding

ABSTRACT Although the giant mottled eel, Anguilla marmorata Quoy & Gaimard, 1824, is widely distributed in the Indo-Pacific region, few ecological studies have been conducted on the species. We investigated the stomach contents of A. marmorata visually and used the DNA-barcode region of the mitochondrial cytochrome c oxidase subunit 1 (CO1) to confirm the species identification. The stomach content analysis revealed that teleosts and crustaceans are the major prey items of A. marmorata. Interestingly, the stomach content of one of the specimens, which was 1029 mm in total length (TL), contained an eel-like fish identified as A. marmorata measuring 510 mm in TL. This study is the first to record cannibalism in the diet of A. marmorata. Although the diet of anguillid eels is generally selective for a single prey species, larger eels are more likely to adopt a diverse feeding habit that includes cannibalism in the tropical river ecosystems.

First record of cannibalism in the giant mottled eel Anguilla marmorata (Actinopterygii: Anguilliformes) as revealed by DNA barcoding

Although the giant mottled eel, Anguilla marmorata Quoy & Gaimard, 1824, is widely distributed in the Indo-Pacific region, few ecological studies have been conducted on the species. We investigated the stomach contents of A. marmorata visually and used the DNA-barcode region of the mitochondrial cytochrome c oxidase subunit 1 (CO1) to confirm the species' identification. The stomach content analysis revealed that teleosts and crustaceans are the major prey items of A. marmorata. Interestingly, the stomach content of one of the specimens, which was 1029 mm in total length (TL), contained an eel-like fish identified as A. marmorata measuring 510 mm in TL. This study is the first to record cannibalism in the diet of A. marmorata. Although the diet of anguillid eels is generally selective for a single prey species, larger eels are more likely to adopt a diverse feeding habit that includes cannibalism in the tropical river ecosystems.(AU)

First record of cannibalism in the giant mottled eel Anguilla marmorata (Actinopterygii: Anguilliformes) as revealed by DNA barcoding

Although the giant mottled eel, Anguilla marmorata Quoy & Gaimard, 1824, is widely distributed in the Indo-Pacific region, few ecological studies have been conducted on the species. We investigated the stomach contents of A. marmorata visually and used the DNA-barcode region of the mitochondrial cytochrome c oxidase subunit 1 (CO1) to confirm the species identification. The stomach content analysis revealed that teleosts and crustaceans are the major prey items of A. marmorata. Interestingly, the stomach content of one of the specimens, which was 1029 mm in total length (TL), contained an eel-like fish identified as A. marmorata measuring 510 mm in TL. This study is the first to record cannibalism in the diet of A. marmorata. Although the diet of anguillid eels is generally selective for a single prey species, larger eels are more likely to adopt a diverse feeding habit that includes cannibalism in the tropical river ecosystems.(AU)