Genomic analyses suggest strong population connectivity over large spatial scales of the commercially important baitworm, Australonuphis teres (Onuphidae)

Abstract

Barriers to dispersal can disrupt gene flow between populations, resulting in genetically distinct populations. Although many marine animals have potential for long-distance dispersal via a planktonic stage, gene flow among populations separated by large geographic distances is not always evident. Polychaetes are ecologically important and have been used as biological surrogates for marine biodiversity. Some polychaete species are used as bait for recreational fisheries, with this demand supporting commercial fisheries for polychaetes to service the retail bait market. However, despite their ecological and economic importance, very little is known about the life history or population dynamics of polychaetes, and few studies have used genetic or genomic approaches to understand polychaete population connectivity. Here, we investigate the population structure of one commonly collected beachworm species used for bait on the eastern coast of Australia, namely, Australonuphis teres, by using genome-wide single-nucleotide polymorphism data. We sampled A. teres from hierarchical nested spatial scales along 900km of the coast in New South Wales. We identified six genetic groups, but there was no clear geographic pattern of distribution. Our results suggest that there is considerable gene flow among the sampled populations. These high-resolution genomic data support the findings of previous studies, and we infer that oceanographic processes promote genetic exchange among polychaete populations in south-eastern Australia.

The Current State of Eunicida (Annelida) Systematics and Biodiversity

“…A study on the deep-sea Hyalinoecia longibranchiata McIntosh, 1885 based on two mitochondrial markers revealed significant population structure between the worms inhabiting several deep-sea sites west of New Zealand, which was hypothesized to be a result of complex current regimes that operate in the area as well as the potential limited ability for larval dispersal [482]. In contrast, the study of Single Nucleotide Polymorphism (SNP) in Australian beach worms, Australonuphis teres, showed no population structure along the eastern coast of Australia, possibly due natural disturbance events, changes in currents and temperature regimes, and/or anthropogenic disturbance [483].…”

Same places, same stories? Genomics reveals similar structuring and demographic patterns for four Pocillopora coral species in the southwestern Indian Ocean

“…mating, gene flow) are cryptic, such as for marine benthic species, population genetics appears useful to infer population structure and connectivity, but also evolutionary histories (e.g. Maggioni et al., 2020; Padovan et al., 2020). Gathering such data appears crucial to assess evolutionary potential and long‐term conservation of species under ongoing changing environments (Gray, 1997).…”

Genetic diversity and restricted genetic connectivity in an endangered marine fish (

“…The successful management of aquatic biodiversity, including endangered species, requires an understanding of the factors that influence range and connectivity (Waples and Punt 2008;Lowe and Allendorf 2010;Beheregaray et al 2017;Padovan et al 2020). Obtaining this knowledge is challenging for many aquatic species, because of habitats that lack physical barriers, varying dispersal potentials of different life stages, ecological differences among species and populations and logistical difficulties of tracking or tracing individuals both spatially and temporally (Ward et al 1994;Avise 1998;Waples 1998;Bargelloni et al 2000;Lowe and Allendorf 2010;Junge et al 2019).…”