Data from: A new generic system for the pantropical Caesalpinia group (Leguminosae)

The Caesalpinia group is a large pantropical clade of ca. 205 species in subfamily Caesalpinioideae (Leguminosae) in which generic delimitation has been in a state of considerable flux. Here we present new phylogenetic analyses based on five plastid and one nuclear ribosomal marker, with dense taxon sampling including 172 (84%) of the species and representatives of all previously described genera in the Caesalpinia group. These analyses show that the current classification of the Caesalpinia group into 21 genera needs to be revised. Several genera (Poincianella, Erythrostemon, Cenostigma and Caesalpinia sensu Lewis, 2005) are non-monophyletic and several previously unclassified Asian species segregate into clades that merit recognition at generic rank. In addition, the near-completeness of our taxon sampling identifies three species that do not belong in any of the main clades and these are recognised as new monospecific genera. A new generic classification of the Caesalpinia group is presented including a key for the identification of genera, full generic descriptions, illustrations (drawings and photo plates of all genera), and (for most genera) the nomenclatural transfer of species to their correct genus. We recognise 26 genera, with reinstatement of two previously described genera (Biancaea Tod., Denisophytum R. Vig.), re-delimitation and expansion of several others (Moullava, Cenostigma, Libidibia and Erythrostemon), contraction of Caesalpinia s.s. and description of four new ones (Gelrebia, Paubrasilia, Hererolandia and Hultholia), and make 75 new nomenclatural combinations in this new generic system.云实类群（Caesalpinia group）是豆科（Leguminosae）云实亚科（Caesalpinioideae）中一个泛热带分布的大型支系，共计包含约205个物种，其属级分类界定长期处于显著的变动状态。本研究基于5个质体标记与1个核核糖体标记开展全新的系统发育分析，类群采样覆盖度极高，囊括了该类群84%（172个）的物种，且包含云实类群此前所有已发表属的代表类群。系统发育分析结果表明，当前将云实类群划分为21个属的分类系统亟需修订。其中，Poincianella、Erythrostemon、Cenostigma以及Lewis于2005年界定的云实属（Caesalpinia sensu Lewis, 2005）等多个属并非单系群；另有若干此前未被分类的亚洲物种可形成独立支系，具备属级分类等级的认定价值。此外，本次近乎全面的类群采样发现了3个不属于任何主要支系的物种，本研究将其认定为全新的单型属。本研究提出了云实类群全新的属级分类系统，内容涵盖属级鉴定检索表、完整的属级特征描述、所有属的图解资料（含手绘插画与实物照片版），以及针对绝大多数属的物种分类学名称转接，即将原物种名称调整至其正确归属的属中。本研究共认可26个属：恢复了2个此前已发表的属（Biancaea Tod.、Denisophytum R. Vig.）；对Moullava、Cenostigma、Libidibia以及Erythrostemon等多个属进行了重新界定与范围扩展；收缩了狭义云实属（Caesalpinia s.s.）的分类范围；发表了Gelrebia、Paubrasilia、Hererolandia以及Hultholia共4个全新的属；并在这一新的属级分类系统中完成了75个全新的分类学组合。