Pennellia yalaensis (Brassicaceae: Halimolobeae), a new species from the Andes of Northern Argentina

Pennellia yalaensis, a new species of Brassicaceae from Jujuy Province in Argentina, is described and illustrated, and its phylogenetic relationships with nearest relatives are discussed. This novelty is morphologically related to P. boliviensis and P. brachycarpa, which also grow in Central Andes of Argentina. However, P. yalaensis clearly differs from both species by the plant height, inflorescence type, and petal length. In addition, trichomes of the basal leaves distinguish the new species from P. boliviensis, and fruit length and number of ovules/seed from P. brachycarpa. Phylogenetic analyses, based on DNA sequences of nuclear ITS and plastid trnL-F regions, confirmed these affinities.

本文记述了采自阿根廷胡胡伊省的十字花科（Brassicaceae）新种亚拉芹叶荠（Pennellia yalaensis），并对其进行了形态描述与图解，同时探讨了其与近缘类群的系统发育关系。该新种在形态上与同样分布于阿根廷中部安第斯山脉的玻利维亚芹叶荠（P. boliviensis）和短果芹叶荠（P. brachycarpa）近缘。但亚拉芹叶荠可通过植株高度、花序类型以及花瓣长度与二者明确区分。此外，基生叶的毛状体特征可将该新种与玻利维亚芹叶荠区分开，而果实长度、胚珠/种子数量则可用于区分其与短果芹叶荠。基于细胞核内转录间隔区（Internal Transcribed Spacer，ITS）与质体trnL-F区的DNA序列开展的系统发育分析，验证了上述亲缘关系。