Work

Genetic Diversity and Putative Origin of the Bait Polychaete, Diopatra aciculata Knox and Cameron 1971 (Annelida: Onuphidae), Occurring in South Africa

Year: 2026

Type: article

Abstract: ABSTRACT The bait polychaete Diopatra aciculata is commercially farmed in Australia and is collected as bait in several South African estuaries. Despite its widespread use, the species' geographic origin remains uncertain, hindering management efforts within sensitive estuarine ecosystems. Mitochondrial Cytochrome Oxidase subunit I (mt COI ) data and ddRAD‐generated single‐nucleotide polymorphisms (SNPs) were used to gain insight into the origin and genetic diversity of D. aciculata . A total of 204 individuals were collected from an aquaculture farm in Australia and the Knysna, Keurbooms, and Swartkops Estuaries in South Africa. The mt COI analyses supported the monophyly of D. aciculata and revealed lower genetic diversity in the South African population compared to the Australian population. Both marker sets revealed significant genetic differentiation between the continental populations that are naturally isolated by the Indian Ocean basin. The SNP dataset revealed low intrapopulation genetic diversity for both the Australian and South African populations. The discordant genetic diversity findings between the mt COI and SNP datasets may be attributed to the differences in the evolutionary rate of the two marker systems. In addition, the low genomic diversity observed in the SNP dataset is consistent with the effects of captive breeding in the Australian aquaculture population; consequently, the effect of sampling bias cannot be excluded. However, the mt COI signal of reduced diversity in South Africa is consistent with an introduced population and both mt COI and SNP‐based RASP analyses recovered Australian samples in a basal position, suggesting Australia as the plausible origin. This highlights the need for precautionary conservation efforts to prevent further spread.

Source: Ecology and Evolution

DOI: 10.1002/ece3.74520

Authors: Stephanie Schoeman, Conrad A. Matthee, Kelvin Hull, Carol A. Simon

Institutions: Stellenbosch University, University of Pretoria

Language: English

Topic: Genetic diversity and population structure

Subfield: Genetics

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

SDG: Life below water

Open Access status: gold

Estimated APC paid: $2,570