Metabarcoding dietary analysis of coral dwelling predatory fish demonstrates the minor contribution of coral mutualists to their highly partitioned, generalist diet

Understanding the role of predators in food webs can be challenging in highly diverse predator/prey systems composed of small cryptic species. DNA based dietary analysis can supplement predator removal experiments and provide high resolution for prey identification. Here we use a metabarcoding approach to provide initial insights into the diet and functional role of coral-dwelling predatory fish feeding on small invertebrates. Fish were collected in Moorea (French Polynesia) where the BIOCODE project has generated DNA barcodes for numerous coral associated invertebrate species. Pyrosequencing data revealed a total of 292 Operational Taxonomic Units (OTU) in the gut contents of the arc-eye hawkfish (Paracirrhites arcatus), the flame hawkfish (Neocirrhites armatus) and the coral croucher (Caracanthus maculatus). One hundred forty-nine (51%) of them had species-level matches in reference libraries (>98% similarity) while 76 additional OTUs (26%) could be identified to higher taxonomic l...

在由隐秘小型物种构成的高度多样的捕食者-猎物系统中，解析捕食者在食物网中的作用颇具挑战。基于DNA的饮食分析可作为捕食者移除实验的补充手段，并能为猎物鉴定提供高分辨率的技术支持。本研究采用宏条形码（metabarcoding）技术，首次揭示了栖息于珊瑚生境、以小型无脊椎动物为食的掠食性鱼类的饮食组成及其功能角色。研究样本采集自法属波利尼西亚的茉莉雅岛，当地的BIOCODE项目已为大量珊瑚伴生无脊椎动物物种生成了DNA条形码（DNA barcode）。焦磷酸测序（Pyrosequencing）数据显示，在弧眼鹰䱵（Paracirrhites arcatus）、火焰鹰䱵（Neocirrhites armatus）以及斑珊瑚匍匐䱵（Caracanthus maculatus）的肠道内容物中，共检出292个操作分类单元（Operational Taxonomic Units, OTU）。其中149个（占比51%）在参考数据库中获得了物种级别的序列匹配（相似性≥98%），另有76个OTU（占比26%）可鉴定至更高的分类阶元（原文未完整）