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Seafood mislabeling threatens customer rights and causes economic loss worldwide. The information on seafood misrepresentation in Thailand is still lacking, and the investigation and monitoring program must be well established. This study investigated the mislabeling status of imported seafood in Thailand using the DNA barcoding technique. A total of 45 imported seafood products from five distributors were included. Scientific, common, local, and market names of seafood samples were obtained from FAO and Fishbase databases. DNA was extracted, and PCR was performed using a universal primer targeting the COI gene. Species of each sample were identified with over 98% similarity based on COI sequence analysis. DNA sequence revealed 11 mislabeled samples. Among substituted species, Pangasianodon hypophthalmus and Thunnus maccoyii were found to be endangered species according to IUCN status. Products obtained from Brand-C showed the highest mislabeling rate (42.85%). The phylogenetic analysis adopted with the TIM2+F+I+G4 model showed the sequenced DNA similar to the NCBI database reference sequence. Overall, mislabeled products of imported seafood were found at the rate of 24.44%, suggesting that strict surveillance for seafood substitution should be implemented in Thailand. [ABSTRACT FROM AUTHOR]

Several parts of rose myrtle, Rhodomyrtus tomentosa, exhibited profound antibacterial and anti-inflammatory activities, suggesting its potential in healthcare and cosmetics applications. During the past few years, the demand for biologically active compounds in the industrial sectors increased. Therefore, gathering comprehensive information on all aspects of this plant species is essential. Here, the genome sequencing using short and long reads was used to understand the genome biology of R. tomentosa. Inter-simple sequence repeats (ISSR) and simple sequence repeats (SSR) markers, and geometric morphometrics of the leaves of R. tomentosa collected across Thai Peninsula, were determined for population differentiation analysis. The genome size of R. tomentosa was 442 Mb, and the divergence time between R. tomentosa and Rhodamnia argentea, the white myrtle of eastern Australia, was around 15 million years. No population structure was observed between R. tomentosa on the eastern and western sides of the Thai Peninsula using the ISSR and SSR markers. However, significant differences in leaf size and shape of R. tomentosa were observed in all locations. [ABSTRACT FROM AUTHOR]

Four new species of troglomorphic Coecobrya Yosii, 1956 are described from caves located in the central and northeastern regions of Thailand. Coecobrya whitteni sp. nov. and C. troglobia sp. nov. are from Khon Kaen province, C. ellisi sp. nov. is from Phetchabun province and C. phitsanulokensis sp. nov. is from Phitsanulok province. They all exhibit remarkable troglobitic characters i.e. elongated antennae, legs and furca, slender claw complex and large body size. Coecobrya whitteni sp. nov. is similar to C. troglobia sp. nov. and they were found a distance of only 3.4 km from each other. However, they are mainly different in the number of An mac on dorsal head and number of chaetae of Th. II. Likewise, C. ellisi sp. nov. is similar to C. phitsanulokensis sp. nov. However, they differ in the number of An mac on the dorsal head, the number of central mac on Abd. II, central mac on Abd. IV, lateral mac on Abd. IV and the number of inner teeth of the claw. Moreover, C. ellisi sp. nov. has orange pigment dots on the body, a unique character, considering that all other troglomorphic Coecobrya species in Thailand are devoid of pigmentation. The results of the molecular approach based on two partial mitochondrial markers (COI and 16S rDNA) and a nuclear gene fragment (28S rDNA) supported the results of morphological species discrimination in separating the four nominal populations as valid species. An updated dichotomous key of Thai troglomorphic Coecobrya species is also given. [ABSTRACT FROM AUTHOR]

Wolbachia, intracellular endosymbionts, are estimated to infect about half of all arthropod species. These bacteria manipulate their hosts in various ways for their maximum benefits. The rising global temperature may accelerate species migration, and thus, horizontal transfer of Wolbachia may occur across species previously not in contact. We transinfected and then cured the alpine fly Drosophila nigrosparsa with Wolbachia strain wMel to study its effects on this species. We found low Wolbachia titer, possibly cytoplasmic incompatibility, and an increase in locomotion of both infected larvae and adults compared with cured ones. However, no change in fecundity, no impact on heat and cold tolerance, and no change in wing morphology were observed. Although Wolbachia increased locomotor activities in this species, we conclude that D. nigrosparsa may not benefit from the infection. Still, D. nigrosparsa can serve as a host for Wolbachia because vertical transmission is possible but may not be as high as in the native host of wMel, Drosophila melanogaster. [ABSTRACT FROM AUTHOR]

Wolbachia (Alphaproteobacteria) are the most widespread endosymbionts of arthropods, manipulating their hosts by various means to maximize the number of host individuals infected. Based on quantitative analyzes of the published literature from Web of Science® and of DNA sequences of arthropod-hosted Wolbachia from GenBank, we made plausible that less than 1% of the expected 100 000 strains of Wolbachia in arthropods is known. Our findings suggest that more and globally better coordinated efforts in screening arthropods are needed to explore the true Wolbachia diversity and to help us understand the ecology and evolution of these host-endosymbiont interactions. [ABSTRACT FROM AUTHOR]

Background: The Indo-Pacific region has the largest number of seagrass species worldwide and this region is considered as the origin of the Hydrocharitaceae. Halophila ovalis and its closely-related species belonging to the Hydrocharitaceae are well-known as a complex taxonomic challenge mainly due to their high morphological plasticity. The relationship of genetic differentiation and geographic barriers of H. ovalis radiation was not much studied in this region. Are there misidentifications between H. ovalis and its closely related species? Does any taxonomic uncertainty among different populations of H. ovalis persist? Is there any genetic differentiation among populations in the Western Pacific and the Eastern Indian Ocean, which are separated by the Thai-Malay peninsula? Genetic markers can be used to characterize and identify individuals or species and will be used to answer these questions., Results: Phylogenetic analyses of the nuclear ribosomal internal transcribed spacer region based on materials collected from 17 populations in the Western Pacific and the Eastern Indian Ocean showed that some specimens identified as H. ovalis belonged to the H. major clade, also supported by morphological data. Evolutionary divergence between the two clades is between 0.033 and 0.038, much higher than the evolutionary divergence among H. ovalis populations. Eight haplotypes were found; none of the haplotypes from the Western Pacific is found in India and vice versa. Analysis of genetic diversity based on microsatellite analysis revealed that the genetic diversity in the Western Pacific is higher than in the Eastern Indian Ocean. The unrooted neighbor-joining tree among 14 populations from the Western Pacific and the Eastern Indian Ocean showed six groups. The Mantel test results revealed a significant correlation between genetic and geographic distances among populations. Results from band-based and allele frequency-based approaches from Amplified Fragment Length Polymorphism showed that all samples collected from both sides of the Thai-Malay peninsula were clustered into two clades: Gulf of Thailand and Andaman Sea., Conclusions: Our study documented the new records of H. major for Malaysia and Myanmar. The study also revealed that the Thai-Malay peninsula is a geographic barrier between H. ovalis populations in the Western Pacific and the Eastern Indian Ocean.