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A rare ascaridoid species, Mawsonascaris australis (Johnston & Mawson, 1943), is reported from the Taiwan Strait for the first time, and the brown guitarfish Rhinobatos schlegelii Müller & Henle (Rhinopristiformes: Rhinobatidae) represents a new fish host. The detailed morphology of M. australis was studied using light and scanning electron microscopy (SEM) based on the newly collected specimens. The results revealed some important, but previously unreported or erroneous, morphological features, including the lateral alae starting well posterior to the base of the ventrolateral lips, the presence of one pair of double paracloacal papillae and a single, small precloacal median papilla on the anterior margin of the cloaca. In addition, in order to determine whether the morphometric difference in the relative lengths of the right and left spicules represents intraspecific or interspecific variation, specimens of M. australis were characterized using molecular approaches by sequencing and analysing the ribosomal internal transcribed spacer (ITS) and mitochondrial cox 1 genes. The results indicate that this morphometric difference represents intraspecific variability. [ABSTRACT FROM AUTHOR]

The starry batfish Halieutaea stellata (Vahl) is a small, benthic fish found in Indo-West Pacific Oceans. However, our present knowledge of the helminth parasites of this fish is still fragmentary. In this study, a total of 29 fish collected from the East and South China Sea were examined to determine the prevalence, intensity and species composition of helminth parasites in H. stellata. Using morphological and molecular approaches, four species of nematodes were found parasitic in this fish host, including the adults and fourth-stage larvae of Raphidascaroides nipponensis Yamaguti 1941; adults and third-stage larvae of Raphidascaris lophii (Wu 1949), third- and fourthstage larvae of Hysterothylacium larval type IV-A of Shamsi, Gasser & Beveridge 2013 and thirdstage larvae of Hysterothylacium amoyense (Hsu 1933). Halieutaea stellata represents a new host record for the three last-named nematodes. Raphidascaroides nipponensis with the highest prevalence (82.5%) and intensity (mean = 13.5) of infection was considered as the dominant parasite species in H. stellata. The detailed morphology of the different developmental stages of the four nematode species was studied using light and scanning electron microscopy. All nematode species were also genetically characterized by sequencing and analysing the internal transcribed spacer (ITS) of the ribosomal DNA. This study provides further data on the occurrence of nematode parasites in H. stellata and also contributes to facilitate an accurate and rapid diagnosis of the infection by these little-known nematodes. [ABSTRACT FROM AUTHOR]

The Chinese Mollisol region is affected by soil erosion. Soil and water conservation (SWC) measures are effective in preventing these phenomena. However, few studies have systematically reviewed soil erosion and SWC measures in this region. The objectives of this paper were to analyze soil erosion and identify typical SWC measures on hillslopes in this Mollisol region. A literature review and analysis were conducted. Soil erosion is widespread in this region and is dominated by snowmelt and wind erosion in winter and spring, rainfall in summer and wind erosion in autumn. The A-horizon thicknesses and organic matter content of the Mollisol decreased with an increase in the number of years of cultivation. Therefore, controlling soil erosion is a means to protect this precious Mollisol resource. The characteristics of 39 SWC measures used on hillslopes were summarized. Among these measures, the contour ridge, large ridge, minimal tillage with residue mulching, no-tillage, straw returning, slope terrace, ridge belt, and agricultural protection forest approaches were the most typical SWC measures. Furthermore, the new tillage measure of half-ridge planting needs to be examined in future studies. In conclusion, it is of practical significance to select suitable SWC measures for different hillslopes in the Mollisol region. [ABSTRACT FROM AUTHOR]