Research On The Biology,Phylogeny And Practice Of Heterocypris Salina

Heterocypris salina is a kind of microcrustacean which is a member of Heterocypris, Cypridae, Podocopa, Ostracoda. This paper does some primary research on H.salina including its biology, molecular identification based on18S rDNA and its role plays in aquaculture.H.salina can live for45days or so. Development time from hatching to adult is22(±2). In this process, appendages have a great change, but there is no change in carapace. At the same time, it also need to molt for8times. It can produce38(±3) eggs with the hatchability of87%or so. H.salina is eurythermal and euryhaline. The tolerance temperatures are8-44℃, while it usually lives in the area at16-38℃. The tolerance salinity is ranging from0-33%o, while the proper salinity for its living is0‰-19‰. It is omnivory, living on bacteria, fungus, algae, humus and so on. This paper provide foundation for further study on H.salina in the future.After DNA extractionn, PCR amplification and sequencing reactions, we got the DNA sequence of Heterocypris salina which is1729bp long. The dataset was analysed with the Neighbor-joining (NJ), Maximum-likelihood (ML), and the Minimum-evolution (ME) algorithms in MEGA5.0to resolve the phylogenetic relationships, and got the similar topologies. From the topologies, Heterocypris had had a radiation differentiation in early evolution. Heterocypris. incongruence and Heterocypris.sp form a clades, and the bootstrap value between them and H.salina is100%,99%and100%respectively, which shows a very close relationship between them. Early research on morphology, finding the shape and appearing time of appendages of H.salina is similar to other Cyprididae, but still have some differences.H.salina has a remarkable effect on removing COD in livestock wastewater. The study shows that H.salina can removing93%COD in livestock wastewater at most within21days when the density of H.salina is200ind/L-300ind/L. But ammonia nitrogen nitrite and nitrate grow higher dramaticlly.The effect of polyculture of H.salina and Daphnia magna, H.salina and Moina macrocopa, H.salina and Moinidae is much better than monoculture of H.salina (p<0.05). But there is no significant difference between the monoculture of H.salina and the polyculture of H.salina and Chydornus sphaericus.(p>0.05)...