- 著者
- Yoshihiro Akiyama Tomonari Okada Takeshi Yuhara
- 出版者
- Aquos Institute
- 雑誌
- 水生動物 (ISSN:24348643)
- 巻号頁・発行日
- vol.2022, pp.AA2022-13, 2022-07-04 (Released:2022-07-04)
We report the presence of mobile macro-epifauna on rafts of pumice generated by the Fukutoku-Oka-no-Ba volcano in 2021 in Oku Port, at the northern end of Okinawa Island. Most of the water surface in the harbor was covered by a thick pumice raft at the time of our observations. Grapsus crabs were the dominant species on the surface of the raft, and many crabs were visible near the quay. No crab was seen to burrow into the raft. These results show that mobile macro-epifauna can expand their distribution to the surface of a pumice raft. However, the presence of a raft is likely to make it difficult for crabs to move between land and water.
- 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.