Morphological identification
According to the morphological characters obtained by the in-situ visual examination and stereomicroscope microscopic examination, the 1200 samples collected in Henan province included 9 species from 2 orders, 4 families and 6 genera(Some of the samples could not be identified morphologically due to damage or missing of distinguishing morphological characters). Among them, the individual morphological variation ofN.denticulate , N.davidi (Bouvier, 1904),M.maculatum and M.nipponense is obvious, especially the morphology of their frontal angles (FIG.S1). The morphological variation of them may be caused by its widely distributed and geographical separation. In addition, consistent with the general distribution trend of freshwater shrimp, freshwater shrimp in this province are mainly composed of Macrobrachium and Neocaridina , among whichM.nipponense is the dominant, followed by N.denticulateand N.davidi .