Radiation of Sacoglossa (Opisthobranchia, Gastropoda) as a function of long term retention of chloroplasts, and usage of their metabolites

纽鳃亚纲和藻类分类群共生之间的共生关系是已知的，尽管这种共生的有效性和可靠性很难被研究。在纽鳃亚纲中，容纳和使用虫黄藻的能力似乎是在不同的时期单独进化的，因为这种现象发生在支枝亚纲的其他家族中。然而，必须强调的是，许多关于共生关系的记录都是通过组织学手段记录下来的，只有极少数物种的光合作用活性得到了测量。在叶绿藻属中，一些物种是众所周知的虫黄藻的宿主，其中一个物种的光合作用活性的原位测量被记录在案。在这项研究中，我们想要研究共生藻类在这种风化属植物可能的辐射中的作用，叶状藻是从热带水域中已知的约18种，被描述为进化出了对虫黄藻住房的特殊形态适应。

Symbiotic relationship between members of the Nudibranchia and the algal taxon Symbiodinium are known, although efficiency and reliability of the symbiosis is hardly investigated for the Nudibranchia. Ability to house and use zooxanthellae seems to have evolved separately different times within the Nudibranchia, since this phenomenon occurs in other familie of the clade Cladobranchia. Nevertheless it has to be emphasized, that many records of the symbiotic relationship have been documented by histological means, and photosynthetic activity has been measured in only very few species. Within the genus Phyllodesmium serveral species are well known to house zooxanthellae, and for one species, in situ measurements of the photosynthetic activity is documented. In this study we want to investigate the role of symbiotic algae in the possible radiation of this aeolid genus, Phyllodesmium, which is known from the tropic waters by about 18 species and which is described to have evolved special morphological adaptations to the housing of zooxanthellae.