When conventional methods fall short: identification of invasive cryptic Golden Apple Snails (Pomacea canaliculata; P. maculata) using environmental DNA

Cryptic invasions are difficult to distinguish and easily overlooked by conventional identification methods, creating false biodiversity information. Molecular markers represent the only reliable method to distinguish cryptic species to date but require individual tissue samples, which is time-inefficient and difficult during low abundance or early colonization. Newly developed Environmental DNA (eDNA) methods may provide a solution. We compared conventional methods (morphological, physicochemical) and molecular methods (DNA and eDNA) to distinguish two putative species of Pomacea, with the aim to develop an early taxon-specific detection method for effective invasive species management. Novel eDNA methods were assessed in semi-natural (mesocosm) and natural waterbodies across Taiwan for species identification. Morphological characters and physicochemical analysis of P. canaliculata and P. maculata shells demonstrated overlapping qualitative and quantitative measures, which were unable to differentiate species. However, DNA-based barcoding (COI gene) differentiated P. canaliculata, and P. maculata and revealed their distribution. Our eDNA analysis demonstrated overall detection rate of P. canaliculata was significantly higher than P. maculata. Importantly, we detected the active presence of P. maculata in Taiwan, although further studies investigation needed to differentiate pure and hybrids individuals. This pioneering eDNA study quickly and effectively detected P. canaliculata and P. maculata, which could revolutionize tracking two immensely invasive and economically destructive species.</p

When conventional methods fall short: identification of invasive cryptic Golden Apple Snails (Pomacea canaliculata; P. maculata) using environmental DNA

Cryptic invasions are difficult to distinguish and easily overlooked by conventional identification methods, creating false biodiversity information. Molecular markers represent the only reliable method to distinguish cryptic species to date but require individual tissue samples, which is time-inefficient and difficult during low abundance or early colonization. Newly developed Environmental DNA (eDNA) methods may provide a solution. We compared conventional methods (morphological, physicochemical) and molecular methods (DNA and eDNA) to distinguish two putative species of Pomacea, with the aim to develop an early taxon-specific detection method for effective invasive species management. Novel eDNA methods were assessed in semi-natural (mesocosm) and natural waterbodies across Taiwan for species identification. Morphological characters and physicochemical analysis of P. canaliculata and P. maculata shells demonstrated overlapping qualitative and quantitative measures, which were unable to differentiate species. However, DNA-based barcoding (COI gene) differentiated P. canaliculata, and P. maculata and revealed their distribution. Our eDNA analysis demonstrated overall detection rate of P. canaliculata was significantly higher than P. maculata. Importantly, we detected the active presence of P. maculata in Taiwan, although further studies investigation needed to differentiate pure and hybrids individuals. This pioneering eDNA study quickly and effectively detected P. canaliculata and P. maculata, which could revolutionize tracking two immensely invasive and economically destructive species.Conservation BiologyEnvironmental Biolog

A Study on the Rearrangement of Dialkyl 1-Aryl-1-hydroxymethylphosphonates to Benzyl Phosphates

The phospha-Brook rearrangement of dialkyl 1-aryl-1-hydroxymethylphosphonates (HPs) to the corresponding benzyl phosphates (BPs) has been elaborated under solid–liquid phase transfer catalytic conditions. The best procedure involved the use of triethylbenzylammonium chloride as the catalyst and Cs2CO3 as the base in acetonitrile as the solvent at room temperature. The substrate dependence of the rearrangement has been studied, and the mechanism of the transformation under discussion was explored by quantum chemical calculations. The key intermediate is an oxaphosphirane. The one-pot version starting with the Pudovik reaction has also been developed. The conditions of this tandem transformation were the same, as those for the one-step HP→BP conversion

Comparative Assessment and Merit Appraisal of Thermally Assisted Machining Techniques for Improving Machinability of Titanium Alloys

Computer vision is presently a very relevant and important tool in both industrial manufacturing and mobile robots. As human vision is the most relevant sense to feed the brain with environmental information for decision making, computer-vision is nowadays becoming the main artificial sensor in the domains of industrial quality assurance and trajectory control of mobile robots