A new, disjunct species of Bahiana (Euphorbiaceae-Acalyphoideae): Phytogeographic connections between the seasonally dry tropical forests of Peru and Brazil, and a review of spinescence in the family

Bahiana is expanded from 1 to 2 species with the description of B. occidentalis K. Wurdack, sp. nov. as a new endemic of the seasonally dry tropical forests (SDTFs) of Peru. The disjunct distribution of Bahiana with populations of B. occidentalis on opposite sides of the Andes in northwestern Peru (Tumbes, San Martín) and B. pyriformis in eastern Brazil (Bahia) adds to the phytogeographic links among the widely scattered New World SDTFs. Although B. occidentalis remains imperfectly known due to lack of flowering collections, molecular phylogenetic results from four loci (plastid matK, rbcL, and trnL-F; and nuclear ITS) unite the two species as does gross vegetative morphology, notably their spinose stipules, and androecial structure. Spinescence in Euphorbiaceae was surveyed and found on vegetative organs in 25 genera, which mostly have modified sharp branch tips. Among New World taxa, spines that originate from stipule modifications only occur in Bahiana and Acidocroton, while the intr..., Datasets derive from fluorescent Sanger sequencing on an ABI 3730xl DNA Analyzer. The reads were assembled with Sequencher v5.2.4 and consensus sequences were manually inserted into the multiple sequence alignments (MSAs) of Carrión et al. (2022), followed by alignment refinements based on a sequence similarity criterion., Data files are text documents that can be opened in any text editor. Commands are designed to be executed in PAUP*, and matrix derivatives then analyzed with other phylogenetic analysis programs.

巴伊亚木属（Bahiana）的类群数量由1个扩展至2个，本研究描述了新种*B. occidentalis* K. Wurdack, sp. nov.，该种为秘鲁季节性干旱热带森林（seasonally dry tropical forests, SDTFs）的特有物种。巴伊亚木属呈现间断分布格局：*B. occidentalis*的种群分布于秘鲁西北部安第斯山脉两侧（通贝斯省、圣马丁省），而*B. pyriformis*分布于巴西东部（巴伊亚州），这一分布格局进一步佐证了广泛离散的新世界季节性干旱热带森林之间的植物区系联系。
尽管因缺乏开花标本，*B. occidentalis*的认知仍不够全面，但基于4个基因位点（质体matK、rbcL、trnL-F以及细胞核ITS）的分子系统发育结果，结合整体营养形态特征（尤其是其具刺托叶）和雄蕊结构，证实了这两个物种同属巴伊亚木属。研究对大戟科（Euphorbiaceae）的刺状结构进行了调查，发现25个属的营养器官存在刺状结构，此类刺大多由尖锐的枝尖特化而来。在新世界类群中，仅由托叶特化形成的刺仅见于巴伊亚木属和Acidocroton属，而……
本数据集的数据来源于ABI 3730xl DNA分析仪（ABI 3730xl DNA Analyzer）的荧光Sanger测序（fluorescent Sanger sequencing）。测序reads使用Sequencher v5.2.4进行组装，一致性序列被手动插入到Carrión等人（2022）的多序列比对（multiple sequence alignments, MSAs）数据集中，随后基于序列相似性标准对多序列比对结果进行了优化。
数据文件为可通过任意文本编辑器打开的文本文档。分析命令设计为可在PAUP*软件中运行，所得矩阵衍生数据可通过其他系统发育分析程序进行后续分析。