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Distribution of two ecologically similar but usually spatially separate ectosymbionts, branchiobdellidans (Annelida) and scutariellids (Platyhelminthes), on atyid shrimp (Neocaridina spp.) is reported from 18 localities in five Provinces of southeastern China. Prevalence was determined for the branchiobdellidan, Holtodrilus truncatus, found at seven locations, the scutariellid, Scutariella japonica, present at every site, and where cohabitation occurred. Both ectosymbionts showed a microhabitat predilection for the host's branchial chambers and instances of cohabitation occurred at all seven locations where H. truncatus were collected, although not on every shrimp. On-site observations of live hosts supporting both ectosymbionts showed that neither H. truncatus nor S. japonica reacted aggressively or defensively towards the other when in close proximity. Instances of imported Chinese Neocaridina spp. into central Honshu Island, Japan, almost certainly came from areas in southeast China identified in this study. These imported populations are predicted to spread northwards into the area where endemic Japanese branchiobdellidans occur.

In the present study, ceramic injection moulding was used to fabricate SiC preform for pressureless infiltration. The influence of various binder compositions consisting of paraffin wax (PW), high density polyethylene (HDPE), polypropylene (PP) and stearic acid (SA) on the characteristics of injection moulded SiC feedstocks has been investigated over the 150–180°C temperature range and the 4–1259 s−1 shear range. The results show that all the feed stocks exhibit pseudoplastic flow behaviour. Compared with 65PW–15HDPE–5SA or 65PW–15PP–5SA, the wax based binder of multi polymer components (65PW–15HDPE–15PP–5SA) is a more suitable binder for SiC ceramic injection moulding due to its good comprehensive rheology and pyrolytic properties. Over a range of temperatures and shear rates, the feedstock made of 65PW–15PP–5SA binder has the lowest viscosity than the other two, which can be attributed to the low molecule weight of PP.