The pantropical plant family Sapotaceae currently includes 65–70 genera. Two genera, Beauvisagea and Boerlagella, were described in 1890s using incomplete material from West New Guinea (Bird's Head Peninsula) and Sumatra, neither of which has been collected since. Their systematic position has long been regarded doubtful and Boerlagella was once placed in its own family, Boerlagellaceae. We show here how useful and important it can be to obtain small leaf fragments from type specimens that are up to 150 years old for molecular analysis aiming to determine their phylogenetic position and clarify their taxonomic status. We used nuclear ribosomal DNA (ETS, ITS) and the nuclear gene RPB2 from 170 terminals to estimate phylogenetic relationships in a Bayesian framework using BEAST. The old type material yielded full length sequences of ETS and ITS from both genera (less successful with RPB2), revealing that both are firmly placed in Planchonella. Boerlagella is placed in synonymy with Planchonella and its type is accepted as Planchonella spectabilis, a species from Sumatra that possibly has gone extinct due to deforestation. Beauvisagea from the Bird's Head Peninsula of western New Guinea is likewise regarded as a synonym of Planchonella and its type, accepted as P. pomifera, is conspecific with Pouteria doonsaf (currently circumscribed to include material of at least two different species), not Planchonella maclayana as earlier believed. Our study also included Planchonella suboppositifolia, an odd species with a character combination in conflict with the current definition of the genus. Our results show that it is sister to a lineage comprising several genera, including Planchonella, and that it represents a distinct lineage constituting a monotypic genus that will be described in a subsequent paper. The most recent classification of subfamily Chrysophylloideae and the character combinations used to distinguish its constituent genera are supported, and our results confirm that taxa can reliably be assigned to a genus based on morphology alone.

中文翻译：

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解决神秘的虎耳草科Beauvisagea和Boerlagella的关系，以及对生的Planchonella suboppositifolia的位置

泛热带植物Sapotaceae目前包括65-70属。1890年代描述了博维萨热格（Beauvisagea）和博拉格拉（Boerlagella）两个属，它们使用的是来自新几内亚西部（伯德角半岛）和苏门答腊的不完整材料，此后均未收集。他们的系统地位长期以来一直令人怀疑，而Boerlagella曾经被安置在自己的家族Boerlagellaceae中。我们在这里显示了从长达150年的类型标本中获取小叶片碎片进行分子分析的重要性和实用性，这些分子标本旨在确定其系统发生位置并阐明其分类地位。我们使用了核糖核糖体DNA（ETS，ITS）和核基因RPB2从170个终端使用BEAST在贝叶斯框架中估计系统发育关系。旧类型的材料从这两个属中产生了ETS和ITS的全长序列（对于RPB2不太成功），表明它们都牢固地放置在Planchonella中。Boerlagella被放置在与同义Planchonella和其类型被接受为Planchonella壮观，从苏门答腊其可能已经灭绝由于森林砍伐的物质。来自新几内亚西部鸟头半岛的Beauvisagea同样被视为Planchonella的代名词，其类型被称为P. pomifera，与Pouteria doonsaf具有共性。（目前限制包括至少两个不同物种的物质），而不是早先认为的马来酸橙。我们的研究还包括了小亚种Planchonella suboppositifolia，这是一种奇特的物种，其字符组合与当前的属定义相冲突。我们的结果表明，它是包含几个属（包括Planchonella）的谱系的姊妹，并且它代表构成单型属的独特谱系，这将在后续论文中进行描述。支持最新的金科亚科分类和用于区分其组成属的字符组合，我们的结果证实，仅根据形态就可以将分类单元可靠地分配给属。