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 .