- 著者
- Takeshi Yuhara Hajime Ohtsuki Jotaro Urabe
- 出版者
- The Plankton Society of Japan, The Japanese Association of Benthology
- 雑誌
- Plankton and Benthos Research (ISSN:18808247)
- 巻号頁・発行日
- vol.18, no.2, pp.106-109, 2023-05-31 (Released:2023-05-30)
- 参考文献数
- 29
- 被引用文献数
- 1
Ghost crabs (genus Ocypode spp.) found on sandy beaches are susceptible with the loss of an ecotone, making them useful as indicators of anthropogenic alteration, such as seawall construction. On the sandy beaches of Sendai Bay on the Pacific coast of the Tohoku region of northern Japan, three Ocypode species have been sympatrically observed in recent years: O. stimpsoni, O. ceratophthalmus, and O. sinensis. However, these three Ocypode species only occur sympatrically from late summer to autumn, immediately after new recruitment. Since they are all juveniles at that period, it is difficult to identify them by morphological characteristics. Thus, we have developed a method for identifying these three Ocypode species. By using two restriction enzymes of AciI and BfaI, we can perform polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis on the 12S-rRNA region of the mitochondrial DNA. As a result, our PCR-RFLP analysis is able to identify all three Ocypode species. Therefore, this method will be a helpful tool for understanding population dynamics and evaluating the sandy beach ecosystem in cases where the three Ocypode species occur sympatrically but identification by morphological features is difficult.
- 著者
- Takehiro Kazama Seiji Ishida Satoshi Shimano Jotaro Urabe
- 出版者
- The Plankton Society of Japan, The Japanese Association of Benthology
- 雑誌
- Plankton and Benthos Research (ISSN:18808247)
- 巻号頁・発行日
- vol.7, no.3, pp.111-125, 2012-08-25 (Released:2013-06-18)
- 参考文献数
- 57
- 被引用文献数
- 7 6
Tintinnid ciliates have been traditionally classified according to morphological and morphometric features of the lorica. To examine if the morphological characteristics of loricae reflect the phylogenetic relationships, we collected 23 tintinnid morphospecies (11 genera) and reconstructed phylogenetic trees based on 84 partial sequences of nuclear small subunit rRNA (SSrRNA) gene fragments of 44 morphospecies from a total of eight families (55 sequences from this study, and 29 sequences from the literature). We found that tintinnid ciliates could be classified into six clades consisting of five major clades. While one clade consisted of one family, each of the other five clades consisted of more than two families. Although two families were found only in one clade, the remaining six families were found in more than two clades. In addition, each of six morphospecies was found in more than two major clades, indicating that they are polyphyletic. Principal coordinate analysis showed that morphology of the lorica overlapped substantially between the clades. These results imply that most of the morphological and morphometric traits of marine tintinnid species do not reflect SSrRNA genetic distances even at family levels. It is necessary to identify new characteristics that reflect phylogenetic relationships robustly.