The diadematid sea urchin Centrostephanus rodgersii occurs in Australia and New Zealand and has undergone recent southward range extension in Australia as a result of regional warming. Clarifying the population genetic structure of this species across its New Zealand range would allow a better understanding of recent and future mechanisms driving range changes in the species. Here, we use microsatellite DNA data to assess connectivity and genetic structure in 385 individuals from 14 locations across the Australian and New Zealand ranges of the species. We detected substantial genetic differentiation among C. rodgersii populations from Australia and New Zealand. However, the population from Port Stephens (located north of Newcastle), Australia, strongly clustered with New Zealand samples. This suggests that the New Zealand populations recently originated from this area, likely via larval transport in the Tasman Front flow that arises in this region. The weak population genetic structure and relatively low genetic diversity detected in New Zealand (global F_st = 0.0021) relative to Australia (global F_st = 0.0339) is consistent with the former population’s inferred history of recent climate-driven expansion. Population-level inbreeding is low in most populations, but were higher in New Zealand (global F_is = 0.0833) than in Australia (global F_is = 0.0202), suggesting that self-recruitment is playing an increasingly important role in the New Zealand region. Our results suggest that C. rodgersii is likely to spread southwards as ocean temperatures increase; therefore, it is crucial that researchers develop a clearer understanding of how New Zealand ecosystems will be reshaped by this species (and others) under climate change.

diadematid 海胆Centrostephanus rodgersii出现在澳大利亚和新西兰，由于区域变暖，最近在澳大利亚经历了向南延伸的范围。阐明该物种在其新西兰范围内的种群遗传结构将有助于更好地了解驱动该物种范围变化的近期和未来机制。在这里，我们使用微卫星 DNA 数据来评估来自该物种澳大利亚和新西兰范围内 14 个地点的 385 个人的连通性和遗传结构。我们在C. rodgersii 中检测到显着的遗传分化来自澳大利亚和新西兰的人口。然而，来自澳大利亚史蒂芬斯港（位于纽卡斯尔以北）的人口与新西兰样本密切相关。这表明新西兰种群最近起源于该地区，可能是通过该地区出现的塔斯曼前流中的幼虫运输。 相对于澳大利亚（全球F _st  = 0.0339），新西兰（全球F _st = 0.0021）检测到的弱种群遗传结构和相对较低的遗传多样性与前种群推断的近期气候驱动扩张历史一致。大多数种群的种群水平近交率较低，但新西兰的种群水平较高（全球F_为 = 0.0833) 而不是澳大利亚（全球F_是 = 0.0202），这表明自我招聘在新西兰地区发挥着越来越重要的作用。我们的结果表明，随着海洋温度的升高，C. rodgersii可能会向南扩散；因此，研究人员更清楚地了解新西兰生态系统将如何在气候变化下被该物种（和其他物种）重塑至关重要。