Pennantia, which comprises four species distributed in Australasia, was the subject of a monographic taxonomic treatment based on morphological characters in 2002. When this genus has been included in molecular phylogenies, it has usually been represented by a single species, P. corymbosa J.R.Forst. & G.Forst., or occasionally also by P. cunninghamii Miers. This study presents the first dated phylogenetic analysis encompassing all species of the genus Pennantia and using chloroplast DNA. The nuclear ribosomal 18S–26S repeat region is also investigated, using a chimeric reference sequence against which reads not mapping to the chloroplast genome were aligned. This mapping of off-target reads proved valuable in exploiting otherwise discarded data, but with rather variable success. The trees based on chloroplast DNA and the nuclear markers are congruent but the relationships among the members of the latter are less strongly supported overall, certainly due to the presence of ambiguous characters in the alignment resulting from low coverage. The dated chloroplast DNA phylogeny suggests that Pennantia has diversified within the last 20 My, with the lineages represented by P. baylisiana (W.R.B.Oliv.) G.T.S.Baylis, P. endlicheri Reissek and P. corymbosa diversifying within the last 9 My. The analyses presented here also confirm previous molecular work based on the nuclear internal transcribed spacer region showing that P. baylisiana and P. endlicheri, which were sometimes considered synonyms, are not sister taxa and therefore support their recognition as distinct species.

中文翻译：

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基于整个叶绿体基因组和核糖体18S-26S重复区域序列的Pennantia（Pennantiaceae）属的系统发育史。

Pennantia由四个分布在大洋洲的物种组成，2002年根据形态特征进行了专论分类学处理。当该属被包括在分子系统发育中时，通常由单个物种Corymbosa JRForst代表。＆G.Forst。，或偶尔也来自C. cunninghamii Miers。这项研究提出了首次过时的系统发育分析，涵盖了Pennantia属的所有物种并使用叶绿体DNA。还使用嵌合参考序列对核糖体18S–26S重复区域进行了研究，针对该参考序列对未映射至叶绿体基因组的读段进行了比对。脱靶读的这种映射被证明对于利用原本被丢弃的数据很有价值，但是成功却相当多。基于叶绿体DNA和核标记的树木是一致的，但总体而言，后者的成员之间的关系得到的支持较弱，这肯定是由于覆盖率低而导致的比对中存在歧义性状。过时的叶绿体DNA系统发育表明，Pennantia在最近的20 My内已经多样化，其中以P. baylisiana（WRBOliv。）GTSBaylis，P。endlicheri Reissek和P. corymbosa为代表的谱系在最后9 My内多样化。此处进行的分析还证实了先前基于核内转录间隔区的分子工作，显示了有时被认为是同义词的Baylisiana和endlicheri P.不是姐妹类群，因此支持它们被识别为不同的物种。