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

裸鳃亚目的成员和藻类分类群共生藻之间的共生关系是已知的，虽然共生的效率和可靠性几乎没有调查裸鳃亚目。在裸鳃类中，安置和使用虫黄藻的能力似乎是在不同的时期分别进化而来的，因为这种现象发生在枝鳃类的其他家族中。然而，必须强调的是，许多共生关系的记录已被记录的组织学手段，和光合作用的活性已被测量只有极少数物种。众所周知，在Phyllodesmium属中，有几种物种可以容纳虫黄藻，其中一种物种的光合活性的原位测量结果被记录在案。在这项研究中，我们要调查的共生藻类的作用，在可能的辐射，这是已知的热带沃茨的Phyllodesmium，约18种，并已演变成特殊的形态适应住房的zooxanthropium。

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.