DNA metabarcoding of spider egg sacs uncovers novel insights into host parasitoid complexes and trophic networks.

DNA metabarcoding is a rapid tool for sequencing a multitude of samples at once, to identify associated organisms. This pioneering study, using DNA metabarcoding of spider egg sacs, establishes a framework for investigating host-parasitoid associations. While traditional rearing methods identified ten arthropod taxa, DNA metabarcoding aided in resolving the identity of 28 arthropod molecular operational taxonomic units (MOTUs), 14 of which represented host-parasitoid associations. The study provides the first documented occurrence of the genus Aphanogmus Thomson (Hymenoptera: Ceraphronoidea: Ceraphronidae) within spider egg sacs. This research also emphasizes the importance of studying lesser-known associations to gain insights into the complexity of ecological networks and trophic interactions within arthropod communities. However, a well-curated DNA reference library and a comprehensive understanding of the functional roles of the studied taxa are essential prerequisites for accurately characterizing these complex trophic networks.