Examination of statocysts of scyphomedusae and cubomedusae to clarify phylogenetic relationships and to develop a method for the age determination of medusae

盘状水母(水母)和盒状水母(立方体水母)具有复杂的感觉器官(线虫)，其中含有无机晶体(定位石)。对一些物种的化学成分、结晶学和这些晶体的形态进行了研究，并在申请人Ilka Sötje博士的参与下，在几份出版物中显示了不同分类群之间的一些差异。持续的检查将有助于确定水母的分类关系，例如根口水母(根口水母)内的有争议的关系，这些关系尚未用分子方法加以澄清。对箱形水母和盘状水母的柱石进行对比检查。到目前为止，它们已经被分成两个不同的分类单元(纲)，但推测它们彼此之间的亲缘关系比目前认为的更密切。两个类群的成年动物的雕像具有非常不同的形态，但最近的研究表明，两组幼体标本的雕像形态相似；这一点应在本申请的背景下进行详细检查。对不同年龄组的水母中的雕像进行详细分析，将导致开发一种水母的年龄确定方法。水母的胶状身体正在缩小和生长，这取决于环境条件。因此，美杜莎身体的大部分部位不能用来确定年龄，但在美杜莎发育过程中，雕像的数量和大小的变化可以用来确定年龄。年龄的确定是研究种群动态的基础，对于阐明观察到的水母在世界范围内大量出现的原因至关重要。

Disc-shaped jellyfish (Scyphozoa) and box jellyfish (Cubozoa) have complex sense organs (rhopalia), which contain anorganic crystals (statoliths). The chemical composition, the crystallography and the morphology of these crystals in some species have been examined and some differences between the distinct taxa were shown in several publications with participation of the applicant, Dr. Ilka Sötje. Continuing examinations shall contribute to the identification of taxonomical relationships of jellyfish, for example the disputed relationships within the root-mouth jellyfish (Rhizostomeae), which have yet to be clarified with molecular methods. The statoliths of the box jellyfish and the disc-shaped jellyfish shall be examined in comparison. To date, they have been grouped into two different taxa (classes), but are presumably more closely-related to each other than is presently assumed. Statoliths of full-grown animals of both taxa have a very different morphology, but recent investigations have shown similarities regarding the statolith morphology in young specimens of both groups; this shall be examined in detail in the context of this application.The detailed analysis of statoliths in medusae of different age groups shall lead to the development of an age-determination method for jellyfish. The gelatinous body of jellyfish is shrinking and growing depending on environmental conditions. Therefore, most body parts of the medusa cannot be used for age determination, but changes in the number and size of the statoliths during medusa development can be used for age-determination. The determination of age is the basis for studies of population dynamics and is crucial for the elucidation of the reasons for the observed worldwide increase in mass occurrences of jellyfish.