Fish diversity of a spring field in Hopong Town, Taunggyi District, Shan State, Myanmar (the Salween River Basin), with genetic comparisons to some "species endemic to Inle Lake".

Hopong, a small town in the Salween (Thanlwin) River Basin, Myanmar, is located 35 km northeast of Inle Lake, a famous ancient lake with numerous endemic fish species. We surveyed the fish fauna of a spring pond in Hopong in 2016, 2019 and 2020 and identified 25 species. Of these, seven, including Inlecyprisauropurpureus and Sawbwaresplendens, had been considered endemic to Inle Lake and at least three species were genetically unique. Eight were suspected or definite introduced species, including Oreochromisniloticus and Gambusiaaffinis. We were unable to identify a nemacheilid species of the genus Petruichthys, which would need a taxonomic examination. The Hopong area is being developed rapidly and, hence, it is crucial to conserve its native fish species and the freshwater ecosystems.

A dataset of fishes in and around Inle Lake, an ancient lake of Myanmar, with DNA barcoding, photo images and CT/3D models.

BACKGROUND: Inle (Inlay) Lake, an ancient lake of Southeast Asia, is located at the eastern part of Myanmar, surrounded by the Shan Mountains. Detailed information on fish fauna in and around the lake has long been unknown, although its outstanding endemism was reported a century ago. NEW INFORMATION: Based on the fish specimens collected from markets, rivers, swamps, ponds and ditches around Inle Lake as well as from the lake itself from 2014 to 2016, we recorded a total of 948 occurrence data (2120 individuals), belonging to 10 orders, 19 families, 39 genera and 49 species. Amongst them, 13 species of 12 genera are endemic or nearly endemic to the lake system and 17 species of 16 genera are suggested as non-native. The data are all accessible from the document "A dataset of Inle Lake fish fauna and its distribution (http://ipt.pensoft.net/resource.do?r=inle_fish_2014-16)", as well as DNA barcoding data (mitochondrial COI) for all species being available from the DDBJ/EMBL/GenBank (Accession numbers: LC189568-LC190411). Live photographs of almost all the individuals and CT/3D model data of several specimens are also available at the graphical fish biodiversity database (http://ffish.asia/INLE2016; http://ffish.asia/INLE2016-3D). The information can benefit the clarification, public concern and conservation of the fish biodiversity in the region.

Processing insect abundance: trading and fishing of zazamushi in Central Japan (Nagano Prefecture, Honshu Island).

BACKGROUND: This article presents the links between technique, commerce and consumption in fishing for zazamushi, a mixture of aquatic insect larvae sold as food souvenirs in Japan. Since zazamushi are mainly collected for economic reasons, we suggest that demand for them has incited technical development among collectors in order to fish more insects. METHODS: Several fishermen and traders were interviewed in semi-directed interviews about their practices and knowledge. To understand the passage from a faunal composition to a commercial composition, our research follows a fishing session closely, as well as the selection of insects that follows it. The insects collected were separated from inanimate matter, then identified, counted and weighed at each stage of the process. RESULTS: Our results suggest that the current technique corresponds to an evolution in subsistence and recreational collecting towards a more systematic fishing of the insects, the aim of which is commercial. In their response to trade issues, the collectors have moved away from the banks to fish the insects in the river current, thus increasing the amount of one species captured compared to another. Although the technique is efficient (and similar to other harvesting techniques), it requires the thorough sorting of organic debris and insects (in our example, the catch contains approximately 78 % of inanimate matter and 22 % of insects, of which 3.29 % are retained for consumption, i.e., less than 2 out of 100 insects). The selection of insects to be consumed takes place mainly during cleaning. This stage depends on traders and reflects the different compositions sold as souvenirs. CONCLUSIONS: Our research shows that the consumption of insects is not explained just by ecological factors that are favourable or unfavourable, but also by technological and economic factors related to their commerce. It suggests that the traders have gradually established the insects that are currently sold as zazamushi and that this commercial development may have had an influence on the preference for insects consumed. It also shows that the cleaning of the insects constitutes an important stage prior to their consumption, one that should not be underestimated.

Isolation and characterization of 39 microsatellite loci in the endangered Japanese loach Leptobotia curta.

A microsatellite-enriched genomic library was obtained for the endangered Japanese loach Leptobotia curta, and 39 dinucleotide markers were successfully isolated and characterized. These markers had between one and nine alleles, with expected heterozygosity ranging from 0 to 0.839, in a population from the Lake Biwa-Yodo River system of Japan. Linkage equilibrium was observed in most loci, and only one locus showed significant deviation from Hardy-Weinberg equilibrium. These microsatellite markers will be useful for genetic diversity studies of wild and captive L. curta populations.

Biomagnification of trace elements in the aquatic food web in the Mekong Delta, South Vietnam using stable carbon and nitrogen isotope analysis.

In the present study, we report the concentrations of 21 trace elements (V, Cr, Mn, Co, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Sn, Sb, Cs, Ba, Hg, Tl, Pb, and Bi), as well as the results of the analysis of stable carbon and nitrogen isotopes, of the various biota that make up the food web in the main stream of the Mekong Delta near Can Tho, South Vietnam. A significant trophic level-dependent increase was found in concentrations of Se, Rb, and Hg with increasing delta(15)N, indicating that an overall biomagnification of these elements occurred. However, the increase of Hg concentration per trophic level was lower than in previous studies. In contrast, the concentration of Mn showed an opposite trend in the food web of the Mekong Delta. In addition to these overall trends, the present study revealed that the biomagnification profiles of trace metals differ between crustaceans and fishes; concentrations of Mn, Cu, Zn, As, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Tl, and Pb were significantly higher in crustaceans, whereas fishes showed higher concentrations of Cr, Rb, and Hg (trophic level determined by delta(15)N). The differences in the biomagnification profile between the major taxa might be attributed to differences in metal accumulation and in detoxification abilities such as possessing a metal-binding protein, e.g., metallothionein (MT).

Embryonic development of the Pacific lamprey, Entosphenus tridentatus.

Embryonic development of the Pacific lamprey, Entosphenus tridentatus, from Japan is described. Egg sizes averaged 1.249 mm (longest axis) and 1.145 mm (shortest axis), the time required for hatching being 11 days at 18 degrees C, shorter than previously reported for a lower water temperature (19 days at 15 degrees C). Early development in E. tridentatus proceeded at a similar rate to that in other lampreys, in spite of different rearing water temperatures for the latter, indicating possible specific differences in basic developmental rates.