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Genetic analyses can reveal a wealth of hitherto undiscovered cryptic biodiversity. For co-occurring and morphologically similar species, the combination of molecular, ecological and morphological analyses provides an excellent opportunity for understanding some of the processes that can lead to divergence and speciation. 

The Australian endemic brown macroalga Durvillaea potatorum (Phaeophyceae) was examined with a combination of genetic and morphological approaches to confifirm the presence of two separate species and to infer the processes that led to their divergence. A total of 331 individuals from 11 sites around coastal Tasmania were collected and measured in situ for a range of morphological and ecological characteristics. Tissue samples were also collected for each individual to allow genetic analyses using mitochondrial (COI) and nuclear (28S) markers. Genetic analyses confifirmed the presence of two deeply divergent clades. The signifificant morphological differentiation, despite high levels of intra-lineage variability, further supported their recognition as distinct species. 

We describe a new species, D. amatheiae sp. nov., which is characterised by a narrower and proportionately shorter stipe, shorter total length, and higher number of stipitate lateral blades and branches than D. potatorum (sensu stricto). The occurrence of both species in sympatry along Tasmania’s eastern and western coasts, as well as their contrasting patterns of haplotype diversity, supports a hypothesis of geographical isolation, allopatric speciation and subsequent secondary contact in response cycles. This research contributes to resolving thephylogenetic relationships, taxonomy and evolution of the ecologically keystone kelp genus Durvillaea.

基因分析可以揭示出大量迄今为止尚未被发现的神秘生物多样性。对于共生和形态相似的物种，分子、生态和形态分析结合的方法为理解一些可能导致分歧和物种形成的过程提供了一个极好的机会。

澳大利亚特有的大型褐藻海洋巨藻(Durvillaea Potatorum)，为了确认两种分化物种的存在并推断导致它们分化的过程，采用遗传和形态学相结合的方法进行了研究。对塔斯马尼亚海岸周围11个采样点的331个样本进行了原位采集和测定，以了解其形态和生态特征。采集每个个体的组织样本，通过线粒体(COI)和核(28S)基因标记进行遗传分析。基因分析证实了两种截然不同的类群的存在。显著的形态分化，高水平的种内变异，进一步支持它们被识别为不同的物种。

本文记述了一新种 D. amatheiae sp. nov.。其特点相比D. potatorum (sensu stricto)更狭窄，柄更短，总长度更短，和更多具柄的侧叶片和分枝数。这两种共生海藻沿塔斯马尼亚海东岸和西岸分布，以及它们的单倍型多样性的对比模式，支持了地理隔离、异源物种形成和对整个更新世冰期的海平面和海流变化的响应后二次接触假说。这项研究有助于解决生态系统关键大型褐藻( Durvillaea属)的系统发育关系、分类学和进化问题。

参考文献：A morphological and phylogenetic investigation into divergence among sympatric Australian southern bull kelps (Durvillaea potatorum and D. amatheiae sp. nov.)