About 10% of aphid species show host alternation. These aphids migrate between primary and secondary host plant species in spring and autumn. Host alternation has not been observed in subfamily Lachninae, although it has been suggested on the basis of circumstantial evidence that Stomaphis japonica (Takahashi) may alternate its host between Quercus serrata (Murray) and Quercus acutissima (Carruth). However, a molecular phylogenetic study has indicated that the Stomaphis individuals feeding on these two plant species belong to two different lineages and aphids feeding on Q. acutissima and Pinus densiflora (Sieb. & Zucc.) belong to the same lineage. Here, we examined host alternation in Stomaphis species by comparing molecular phylogenetic identities, morphological features, and life cycles. The molecular analysis and morphological examination showed that aphids feeding on Q. acutissima were the same as those feeding on P. densiflora, whereas aphids feeding on Q. serrata were different from those feeding on Q. acutissima or on P. densiflora. Furthermore, winged aphids were observed on both Q. acutissima and P. densiflora in autumn, but we did not observe winged aphids on Q. serrata. These results indicate that Stomaphis (Walker) individuals feeding on Q. serrata and Q. acutissima belong to two species, one that feeds year-round on Q. serrata, and another, heteroecious species that feeds on P. densiflora as a primary host and on Q. acutissima as a secondary host. This study documents host alternation in subfamily Lachninae for the first time and discusses the acquisition of host alternation by Stomaphis from evolutionary and ecological perspectives.

中文翻译：

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季节性迁移蚜属Stomaphis（半翅目：蚜科）：在亚科Lachninae木本植物主机之间交替的发现

大约10％的蚜虫物种显示出寄主轮换。这些蚜虫在春季和秋季在主要和次要寄主植物之间迁移。尽管根据间接证据表明日本气孔鲈（高桥）可能在锯齿栎（Murray）和尖吻栎（Carruth）之间轮替其宿主，但尚未在Lachninae亚科中观察到寄主交替。然而，一项分子系统发育研究表明，以这两种植物为食的气孔虫个体属于两个不同的谱系，以食蚁Q和松果为食的蚜虫（Sieb。＆Zucc。）属于同一血统。在这里，我们通过比较分子系统发育身份，形态特征和生命周期，检查了气孔菌物种中的宿主轮换。分子分析和形态学检查表明蚜虫喂养麻栎的相同。在这些馈送赤松，而蚜虫喂养枹来自这些馈送不同麻栎或赤松。此外，秋天在Acutissima和P. densiflora上都观察到有翅的蚜虫，但在锯缘的Q. serrata上没有观察到有翅的蚜虫。。这些结果表明，Stomaphis喂养（沃克）个人在枹和麻栎属于两个物种，一个在饲料全年枹，和另一个，heteroecious种上饲料赤松作为主要主机和在acutissima上作为次要宿主。亚科Lachninae此研究文件主机交替首次和讨论收购主机交替通过Stomaphis从进化和生态的观点。