Earth, Environment & Biological Sciences School, Science & Engineering Faculty, Queensland University of Technology, Brisbane, QLD 4001, Australia.
Mol Phylogenet Evol. 2012 Oct;65(1):163-73. doi: 10.1016/j.ympev.2012.05.034. Epub 2012 Jun 7.
Despite their ecological significance as decomposers and their evolutionary significance as the most speciose eusocial insect group outside the Hymenoptera, termite (Blattodea: Termitoidae or Isoptera) evolutionary relationships have yet to be well resolved. Previous morphological and molecular analyses strongly conflict at the family level and are marked by poor support for backbone nodes. A mitochondrial (mt) genome phylogeny of termites was produced to test relationships between the recognised termite families, improve nodal support and test the phylogenetic utility of rare genomic changes found in the termite mt genome. Complete mt genomes were sequenced for 7 of the 9 extant termite families with additional representatives of each of the two most speciose families Rhinotermitidae (3 of 7 subfamilies) and Termitidae (3 of 8 subfamilies). The mt genome of the well supported sister-group of termites, the subsocial cockroach Cryptocercus, was also sequenced. A highly supported tree of termite relationships was produced by all analytical methods and data treatment approaches, however the relationship of the termites+Cryptocercus clade to other cockroach lineages was highly affected by the strong nucleotide compositional bias found in termites relative to other dictyopterans. The phylogeny supports previously proposed suprafamilial termite lineages, the Euisoptera and Neoisoptera, a later derived Kalotermitidae as sister group of the Neoisoptera and a monophyletic clade of dampwood (Stolotermitidae, Archotermopsidae) and harvester termites (Hodotermitidae). In contrast to previous termite phylogenetic studies, nodal supports were very high for family-level relationships within termites. Two rare genomic changes in the mt genome control region were found to be molecular synapomorphies for major clades. An elongated stem-loop structure defined the clade Polyphagidae + (Cryptocercus+termites), and a further series of compensatory base changes in this stem-loop is synapomorphic for the Neoisoptera. The complicated repeat structures first identified in Reticulitermes, composed of short (A-type) and long (B-type repeats) defines the clade Heterotermitinae+Termitidae, while the secondary loss of A-type repeats is synapomorphic for the non-macrotermitine Termitidae.
尽管白蚁（Blattodea：Termitoidae 或 Isoptera）作为分解者具有生态意义，并且作为膜翅目以外最具多样性的社会性昆虫群体具有进化意义，但白蚁的进化关系尚未得到很好的解决。先前的形态学和分子分析在科一级上存在强烈冲突，并且骨干节点的支持度很差。本文制作了白蚁的线粒体（mt）基因组系统发育，以检验已识别的白蚁科之间的关系，提高节点支持度，并检验在白蚁 mt 基因组中发现的稀有基因组变化的系统发育实用性。对 9 个现存白蚁科中的 7 个科的完整 mt 基因组进行了测序，并对两个最具多样性的科 Rhinotermitidae（7 个亚科中的 3 个）和 Termitidae（8 个亚科中的 3 个）的每个代表进行了补充。还对支持度很高的白蚁姐妹群——半社会性蟑螂 Cryptocercus 的 mt 基因组进行了测序。通过所有分析方法和数据处理方法都产生了白蚁关系的高度支持树，但白蚁+Cryptocercus 进化枝与其他蟑螂谱系的关系受到白蚁相对于其他直翅目生物强烈核苷酸组成偏差的高度影响。该系统发育支持先前提出的超科白蚁谱系 Euisoptera 和 Neoisoptera，后来衍生的 Kalotermitidae 是 Neoisoptera 的姐妹群，以及一个单系的湿木白蚁科（Stolotermitidae、Archotermopsidae）和收获白蚁科（Hodotermitidae）。与先前的白蚁系统发育研究相比，白蚁科内的关系节点支持度非常高。在 mt 基因组调控区发现了两个罕见的基因组变化，它们是主要进化枝的分子synapomorphies。一个伸长的茎环结构定义了 Polyphagidae +（Cryptocercus+termites）进化枝，并且这个茎环中的进一步系列补偿碱基变化是 Neoisoptera 的 synapomorphy。首次在 Reticulitermes 中鉴定出的复杂重复结构，由短（A型）和长（B 型）重复组成，定义了 Heterotermitinae+Termitidae 进化枝，而 A 型重复的二次丢失是非Macrotermitinae Termitidae 的 synapomorphy。
