A new species of Novastoa Finlay, 1926 (Mollusca: Gastropoda: Vermetidae) from coral reefs of the Pacific Ocean

A new species of vermetid gastropod belonging to the genus Novastoa Finlay, 1926, N. rapaitiensis sp. nov., is described from French Polynesia and the Great Barrier Reef, based on morpho-anatomical and molecular data, increasing the recognized extant diversity of this genus from five to six species. The new species is characterized by the largest operculum in the genus to date, with a conspicuous spindle-shaped mammilla that readily distinguishes this species from its congeners. Based on available data, members of the studied populations of N. rapaitiensis sp. nov. are interpreted as a single species, although slight morphological and color differences exist between localities separated by up to 7000 km. The larval development of N. rapaitiensis sp. nov. is inferred to be direct, raising new questions about genetic connectivity and dispersal trajectories across a vast geographic range. Additional molecular data may prove helpful in refining our current knowledge on the morphological variability within this species and verifying the degree of cryptic diversity in this genus.

基于形态解剖学和分子数据的分析，新发现的属Novastoa Finlay，1926年描述的海洋软体动物门蜗牛类新物种N. rapaitiensis sp. nov.，源自法属波利尼西亚和大堡礁，此发现将本属已知现存物种多样性从五种增加至六种。该新物种以其迄今为止属内最大的贝壳而著称，其显著的长圆柱形乳头易于将其与其同属物种区分开来。根据现有数据，研究的新物种N. rapaitiensis sp. nov.的种群成员被解释为单一物种，尽管在相隔高达7000公里的不同地点之间存在轻微的形态和颜色差异。新物种N. rapaitiensis sp. nov.的幼虫发育过程推断为直接发育，这引发了关于跨越广阔地理范围的遗传联系和扩散轨迹的新问题。额外的分子数据可能有助于细化我们对该物种形态变异性当前知识的理解，并验证该属内隐秘多样性的程度。