Data from: Reinstatement of the Southern Andean genus Stenodraba (Brassicaceae) based on molecular data and insights from its environmental and geographic distribution

Stenodraba (Brassicaceae) included a group of eight species distributed along the Andes of South-Central Argentina and Chile. All of its species were subsequently transferred to other genera and are currently treated in Pennellia (Tribe Halimolobeae) and Weberbauera (Tribe Thelypodieae). However, the phylogeny of Stenodraba and its tribal placement were never analyzed using molecular data. The lack of such studies, as well as paucity of herbarium collections suggesting that some species are vulnerable and/or endangered, prompted us to address the molecular phylogeny of Stenodraba. For this purpose, we generated comprehensive molecular phylogenies using nuclear (ITS) and plastid (trnL-F and trnH-psbA) data, and conducted different niche comparisons in the environmental and geographic space using climate data processed both by ordination and species distribution modelling (SDM) techniques. The results demonstrated that Stenodraba belongs to the South American tribe Eudemeae and is related to the genera Aschersoniodoxa, Brayopsis, Dactylocardamum, and Eudema. Stenodraba species formed two, strongly supported clades, and although molecular data did not recover monophyly of the genus, this hypothesis was not significantly rejected. The main clades were differentiated in their climatic niches (both in the environmental and geographical spaces), and niche overlap was greater within than between clades. Systematic implications, including a key distinguishing Stenodraba from the remaining genera of Eudemeae and a synopsis of its species, are also provided.

十字花科（Brassicaceae）的Stenodraba属曾包含8个物种类群，分布于阿根廷中南部及智利境内的安第斯山脉沿线。其后该属的所有物种均被移至其他属，目前分别归入彭内拉属（Pennellia，Halimolobeae族）和韦伯鲍拉属（Weberbauera，Thelypodieae族）。然而，此前从未有研究利用分子数据对Stenodraba属的系统发育及其族级分类地位进行分析。鉴于此类研究的缺失，加之标本馆馆藏匮乏提示部分物种存在易危乃至濒危风险，本研究旨在开展Stenodraba属的分子系统发育研究。为此，本研究利用核基因组（ITS）及质体基因组（trnL-F、trnH-psbA）数据构建了全面的分子系统发育树，并通过排序分析与物种分布模型（SDM）技术处理的气候数据，在环境与地理空间中开展了多样的生态位对比研究。研究结果显示，Stenodraba属隶属于南美Eudemeae族，与Aschersoniodoxa属、Brayopsis属、Dactylocardamum属及Eudema属亲缘关系相近。Stenodraba属的物种形成了两个支持度极高的演化支，尽管分子数据未支持该属为单系群，但该假说并未被显著否决。两个主要演化支的气候生态位（包括环境空间与地理空间）存在显著分化，且演化支内部的生态位重叠度高于演化支之间。本研究还讨论了其分类学意义，包括区分Stenodraba属与Eudemeae族其余各属的检索表，以及该属物种的分类综述。