Search Results (6)

In this study, we present the first attempt at a molecular phylogenetic analysis of the entire family of Cordulegastridae involving 60% of its known species. Our analysis is in favor of reclassification of the members of the family into four genera: (i) the monophyletic genus Anotogaster Selys, 1854, with the number of known species reduced by three synonymizations; (ii) the genus Cordulegaster Leach in Brewster, 1815 including all members of the boltonii group and, as a preliminary solution, the American species C. virginiae Novelo-Gutiérrez, 2018 and, very tentatively, C. diadema Selys, 1868. The bidentata group forms a genus of its own, for which we restored the name Thecagaster Selys 1854, stat. rev. Cordulegaster pekinensis McLachlan in Selys, 1886, currently considered as Neallogaster pekinensis, was placed by us in Thecagaster as well. The genus Neallogaster Cowley, 1934 needs further investigation involving all remaining species listed in it. The genus Zoraena Kirby, 1890, stat. rev., was recovered to accommodate the remaining American species of Cordulegaster. We synonymized three species of Anotogaster: Anotogaster gregoryi Fraser, 1923 = Anotogaster xanthoptera Lohmann, 1993, syn. nov.; Anotogasterkuchenbeiseri (Förster, 1899) = Anotogaster antehumeralis Lohmann, 1993, syn. nov.; Anotogaster kuchenbeiseri (Förster, 1899) = Anotogaster cornutifrons Lohmann, 1993, syn. nov., based on examination of the existing type specimens. The type of specimens of A. klossi Fraser, 1919 = A. flaveola Lohmann 1993 syn. confirm., were also examined, and their synonymy was confirmed. The isolated populations of A. sieboldii (Selys, 1854) from the archipelagos of Okinawa and Amami Oshima in Japan, respectively, should be regarded as separate species, which will be described elsewhere. Furthermore, we suggest the synonymization of Cordulegaster parvistigma Selys 1873 syn. nov. with Thecagaster brevistigma (Selys 1854) comb. restaur. Full article

People who drink naturally hardened water may experience longevity-enhancing effects. In this study, we investigated water hardness and longevity from both geological and epidemiological perspectives in Japan’s Amami islands, where drinking water is drawn from coralline or non-coralline bedrock. We investigated drinking water hardness, limestone bedrock occupancy, and the centenarian rate (number per 10,000 population) by municipality across four adjacent islands (Amami-Oshima (non-coralline), Tokunoshima, Okinoerabu, and Yoron (predominantly coralline)). Limestone was strongly correlated with water hardness (r = 0.99; p < 0.01), occupying more than 80% of the bedrock where the water was the hardest (Tokunoshima’s Isen municipality: 86.5%; Yoron: 82.9%) and being scarcely detectable in Amami-Oshima (0.0 to 0.2%), where the water was the least hard. The centenarian rate was also strongly correlated with water hardness (r = 0.84, p < 0.01), with the highest figures in Yoron (29.7) and Isen (29.2), and the lowest in Amami-Oshima (0.0 to 12.2). Therefore, we hypothesize a potentially beneficial effect of hard water on longevity when that water is drawn from coralline limestone. Water hardness is determined by the water content of calcium and magnesium and may plausibly influence life expectancy through a preventative effect against cardiovascular disease. Our findings are of interest to current debates about future global access to drinking water and its quality. Full article

Two previously unreported onnamide analogs, 2Z- and 6Z-onnamides A (1 and 2), were isolated from the marine sponge Theonella conica collected at Amami-Oshima Is., Kagoshima Prefecture, Japan. Structures of compounds 1 and 2 were elucidated by spectral analysis. Structure–activity relationships (SARs) for effects on histone modifications and cytotoxicity against HeLa and P388 cells were characterized. The geometry in the polyene systems of onnamides affected the histone modification levels and cytotoxicity. Full article

Despite all efforts and massive investments, the restoration of mangroves has not always been successful. One critical reason for this failure is the vulnerability of young mangroves, which cannot grow because of hydrodynamic disturbances in the shallow coastal water. For a comprehensive study bridging ecological and engineering principles, a portable community-based reef is proposed to shield mangroves from waves during the early stages of their growth. A series of field observations were conducted on Amami Oshima Island (Japan), to observe the growth of young mangroves and their survival rate under moderate wave conditions. The evolution of young mangroves was also observed in the laboratory under a controlled indoor environment. At the research site, it was confirmed that, after six months of germination, young mangroves could withstand normal high waves. Laboratory-grown plants were lower in height and had fewer leaves compared with the native mangroves on Amami. Based on these results, an economical reef system was designed. For this purpose, the Ahrens formula for the design of a low-crested reef breakwater was revisited. The results showed that a 50-cm-high reef constructed with 15-kg stones can protect mangroves that are a few months old and effectively promote early mangrove growth. Full article

Pufferfish of the family Tetraodontidae possess tetrodotoxin (TTX) and/or saxitoxins (STXs), but the toxin ratio differs, depending on the genus or species. In the present study, to clarify the distribution profile of TTX and STXs in Tetraodontidae, we investigated the composition and intra-body distribution of the toxins in Canthigaster valentini. C. valentini specimens (four male and six female) were collected from Amami-Oshima Island, Kagoshima Prefecture, Japan, and the toxins were extracted from the muscle, liver, intestine, gallbladder, gonads, and skin. Analysis of the extracts for TTX by liquid chromatography tandem mass spectrometry and of STXs by high-performance liquid chromatography with post-column fluorescence derivatization revealed TTX, as well as a large amount of STXs, with neoSTX as the main component and dicarbamoylSTX and STX itself as minor components, in the skin and ovary. The toxins were also detected in the other tissues, but in much lower amounts than in the skin and ovary. The TTX/STX ratio varied greatly, depending on the tissue, but TTX was the major toxin component in the whole body, and STXs accounted for 25% and 13% of the total toxin amount in males and females, respectively. Like the marine pufferfish of the genus Arothron, C. valentini should be considered a pufferfish with considerable amounts of both TTX and STXs present simultaneously. Full article

Male pufferfish (Torquigener albomaculosus) construct “mystery circles”, geometric circular structures with radially aligned peaks and valleys, on sandy seabeds for reproduction. We discovered an earliest-stage mystery circle composed of dozens of irregular depressions. The structure changed to a primitive circular form with radially aligned valleys and a circular depression in the central area on day 2. The number of valleys increased, and the radius of the structure was much smaller than that of the final structure. These features were observed from days 2 to 4, considered the early stage of construction. The mystery circle had radially aligned peaks and valleys with a central flat area, while the radius and the differences in elevation between the peaks and valleys were increasing. These features, which were observed from days 5 to 8, were considered the middle stage of construction. On day 9, the mystery circle was completed. An irregular pattern was formed in the central area, and the radially aligned peaks were decorated with shell and coral fragments. These are the first recorded observations of construction of a mystery circle from the earliest stage. Full article