<![CDATA[Microplastic pollution is recognized as a threat to marine ecosystems, yet its impacts on early life stages of mesopelagic fishes remain poorly understood. This study investigated the occurrence and characteristics of microplastic ingestion in fish larvae of the families Myctophidae and Gonostomatidae from the Banggai Sea, Indonesia. Morphometric measurements and microplastic content were analyzed in 40 larvae (20 per family). Gonostomatidae larvae, despite being smaller in total length, exhibited significantly larger mouth widths and ingested more microplastic particles (mean = 3.90 ± 0.72 particles) than Myctophidae (mean = 3.40 ± 0.38 particles). Correlation analysis showed no significant relationships between morphometric traits and microplastic abundance. Transparent and purple particles dominated ingestion profiles, while red and black particles were detected only in Myctophidae. Fiber-shaped particles composed predominantly of polyethylene terephthalate (PET) were the most abundant in both taxa. Statistical analyses (Mann–Whitney U, chi-square, and correspondence analysis) revealed significant differences in particle color composition between families (χ² = 23.73, p = 0.001; Cramér’s V = 0.403) but not in particle shape. These findings highlight that species-specific traits may influence microplastic exposure during early developmental stages, providing new insights into pollution pathways affecting oceanic food webs in the Indo-Pacific deep-sea environment.]]>
