Ostracods as a proxy for paleoclimatic change: An essential role of bioculture experiment taking Limnocythere inopinata (Crustacea: Ostracoda) as an example

Ostracods are favorable research materials for paleoclimatic reconstruction. Limnocythere inopinata, a commonly Holarctic species, is used frequently in paleoclimatic research. However, few ostracods bioculture data and its applications for paleoclimatic reconstruction have largely hindered deep understanding of the relationship between ostracods proxy and paleoclimatic change. Here we present the specific bioculture experiments on L. inopinata for the first time and statistically analyzed the survival curves of the experimental groups. The living specimens were collected from Lake Jiang co in northern Tibetan Plateau. Our results show that L. inopinata population living in Lake Jiang co prefers a narrow temperature range of 11–14 °C and a narrow salinity range of 3.50–6.50‰, respectively. The tolerance range is 11–17 °C for temperature and 0.50–9.50‰ for salinity. The results are apparently different from previous studies that this species has a very wide temperature (0.5–35.0 °C) and salinity range (0.18–18‰). Coupling with the records of other L. inopinata populations, it should be noted that L. inopinata populations living in different regions have adapted local aquatic environment, thus developed specific preference. This finding suggests that it is necessary to reassess the interpretation of L. inopinata valves in lacustrine sediments. As this example demonstrates, bioculture experiments on ostracods play an essential role in further realizing the relationship between ostracods proxy and paleoclimatic change.