$1 DNA barcodes for reconstructing complex phenomes and finding rare species in specimen-rich samples

Area of Science:

• Taxonomy and Systematics
• Molecular Ecology
• Biodiversity Science

Background:

• Taxonomic challenges include small size, abundance, and rarity of species, hindering identification.
• Morphologically distinct life stages complicate species identification in mass samples.
• Limited taxonomists and difficulties in finding rare species impede biodiversity assessments.

Discussion:

• Next-generation sequencing (NGS) offers a cost-effective solution for processing large biodiversity samples.
• Molecular barcodes generated at <$0.40 USD per specimen enable rapid species identification.
• The protocol successfully generated molecular markers for 1015 tropical midge specimens.

Key Insights:

• Barcodes clustered into 52-61 molecular operational taxonomic units (OTUs) using Objective Clustering, GMYC, and PTP methods.
• Over half of the identified species were rare (<10 specimens).
• Larval and adult stages were successfully matched for 24 OTUs, linking different life forms.

Outlook:

• This protocol facilitates high-throughput processing of specimen-rich samples in biodiversity surveys.
• It aids in resolving taxonomic uncertainties for rare and morphologically cryptic species.
• Enables more comprehensive and cost-effective biodiversity assessments globally.