Urban Microplastic Pollution Revealed by a Large-Scale Wetland Soil Survey.

Microplastics (MPs), as a new persistent pollutant, can be emitted and accumulated in urban environments, but there is no detailed information on the driving factors of MP pollution. In this study, through a large-scale wetland soil survey, the features of MPs were characterized in each urban area. The results showed an average abundance to be 379 n/kg in wetland soil. Polypropylene, fiber or fragment, and black color were common composition, shape, and color, respectively. The spatial distribution information showed that MP abundance was significantly relevant to the distance from the urban economic center. Furthermore, the correlation and regression analysis revealed that MP abundance was related to soil heavy metal and atmospheric particle (PM10 and PM2.5) concentrations (P < 0.05), while the promotion of socioeconomic activities (urbanization level, population density, etc.) may aggravate the pollution degree. Additionally, by using structural equation modeling, it was found that the urbanization level was the dominant factor driving the MP pollution degree, with a total effect coefficient of 0.49. Overall, this work provides multi-sided environmental information regarding MP pollution in urban ecosystems, which is significant for follow-up studies of MP pollution control and restoration.

Stenorynchoacrum xijiangensis, a new genus and a new species of Labeoninae fish from Guangxi, China (Teleostei: Cyprinidae.

Stenorynchoacrum xijiangensis, a new genus and a new species of Cyprinidae, is described from a tributary of the Zhujiang River (Pearl River) in Guangxi Province, China. It can be distinguished from other genera of Labeoninae by the following characters: middle part of rostral cap undeveloped, narrow, only covering the base of the upper jaw, both sides of rostral cap well developed and extending upward, rostral cap connected the lower lip with free lateral margin, the median part of lower lip protruded to form a round fleshy pad, whose posterior margin continuous with the mental region.

Taxonomic revision of the Southeast Asian brook barb genus Poropuntius Smith, 1931 (Teleostei, Cyprinidae) with description of a new species from Vietnam.

Molecular data from samples encompassing 22 nominal species of Poropuntius indicate that the species-level diversity in the genus has been vastly overestimated, likely due to inadequate taxon and geographic sampling and reliance on morphological characters that vary intra-specifically. The latter includes discrete mouth morphologies related to alternate feeding strategies (ecomorphs) within populations. One new species is described, Poropuntiusanlaoensis Hoàng, Pham & Tran, sp. nov., and 17 synonyms of six valid species names of Poropuntius, P.krempfi, P.alloiopleurus, P.huangchuchieni, P.laoensis, P.kontumensis, and P.deauratus, are recognised. Additional taxonomic changes in this widespread and generally poorly known genus are likely as more molecular and morphological data become available.

Time-dependent effects of microplastics on soil bacteriome.

Microplastic threats to biodiversity, health and ecological safety are adding to concern worldwide, but the real impacts on the functioning of organisms and ecosystems are obscure owing to their inert characteristics. Here we investigated the long-lasting ecological effects of six prevalent microplastic types: polyethylene (PE), polypropylene (PP), polyamide (PA), polystyrene (PS), polyethylene terephthalate (PET), and polyvinyl chloride (PVC) on soil bacteria at a 2 % (w/w) level. Due to the inertia and lack of available nitrogen of these microplastics, their effects on bacteriome tended to converge after one year and were strongly different from their short-term effects. The soil volumes around microplastics were very specific, in which the microplastic-adapted bacteria (e.g., some genera in Actinobacteria) were enriched but the phyla Bacteroidetes and Gemmatimonadetes declined, resulting in higher microbial nitrogen requirements and reduced organic carbon mineralization. The reshaped bacteriome was specialized in the genetic potential of xenobiotic and lipid metabolism as well as related oxidation, esterification, and hydrolysis processes, but excessive oxidative damage resulted in severe weakness in community genetic information processing. According to model predictions, microplastic effects are indirectly derived from nutrients and oxidative stress, and the effects on bacterial functions are stronger than on structure, posing a heavy risk to soil ecosystems.

A review of the Cypriniform tribe Yunnanilini Prokofiev, 2010 from China, with an emphasis on five genera based on morphologies and complete mitochondrial genomes of some species.

The loach tribe Yunnanilini from China is reviewed here using morphological characters and complete mitochondrial genomes of select species. Molecular data suggest that the tribe Yunnanilini is not monophyletic and can be divided into three clades. Species of the Yunnanilus nigromaculatus group form an independent genus and are placed in Eonemachilus. In the phylogenetic tree, Y. jinxiensis clusters with Paranemachilus genilepis, and Y. pulcherrimus clusters with Micronemacheilus cruciatus, indicating that Y. jinxiensis and Y. pulcherrimus belong to Paranemachilus and Micronemacheilus, respectively. Based on morphological data, Y. bailianensis and Y. longibarbatus are placed in Heminoemacheilus, while Y. jinxiensis and Y. pulcherrimus, are placed in Paranemachilus and Micronemacheilus, respectively. Yunnanilus niulanensis and Y. qujinensis are treated as junior synonyms of Eonemachilus caohaiensis. Eonemachilus, Micronemacheilus, and Yunnanilus are show short separation between anterior and posterior nostrils. The genera can be distinguished from each other by mouth structure, lateral line and cephalic lateral-line canals, and papillae on median part of both lips. The anterior and posterior nostrils of Heminoemacheilus and Paranemachilus are closely set. Paranemachilus and Micronemacheilus are distinguished by cheeks covered with scales and lips with papillae, respectively. Our phylogenetic tree and morphological characters support Traccatichthys as a valid genus, which can be distinguished from Micronemacheilus by anterior and posterior nostrils closely set (vs. clearly separated). Four species are placed in Traccatichthys.

Two new species of loaches from the Irrawaddy River basin, Chin State, Myanmar (Teleostei: Cypriniformes: Nemacheilidae).

Schistura falamensis, a new species of nemacheilid loach, is described from the main channel of the Manipur River in the Irrawaddy River basin, Chin State, western Myanmar. It differs from other congeners of the genus Schistura by a combination of the following characters: 5-8 vertical bars on body; indistinct bars in front of dorsal-fin origin; bars on posterior part of body regular, twice as wide as interspace; black caudal basal bar dissociated, short, not reaching ventral extremity; males with suborbital flap; lateral line complete; and processus dentiformis weak. Schistura altuscauda is a new species described from the Htin stream, Mindat Town, Chin State, Myanmar. It can be distinguished from other congeners by a combination of the following characters: high caudal peduncle (14.0-20.3% SL), strong processus dentiformis on upper jaw; 7-19 bars on flank of body, bars in front of dorsal fin obviously thinner than those behind, sometimes fused in front of dorsal fin; lateral line complete; males with prominent suborbital flap; and pelvic lobe present.

Opsarius putaoensis, a new species of subfamily Danioninae (Actinopterygii, Cyprinidae) from the Irrawaddy River basin in northern Myanmar.

Opsarius putaoensis, new species, is described from the Mali Hka River, a tributary of the Irrawaddy River in northern Myanmar. For convenience of identification, Opsarius sensu Rainboth (1991) in Southeast Asia and India can be divided into two species groups based on the number of anal-fin rays: (1) the O. gatensis species group with more than 12 branched anal-fin rays, and (2) the O. barna species group with fewer than 11 branched anal-fin rays. The remaining species of the O. barna species group can be divided into two species subgroups by the presence or absence of barbels: (1) the O. chatricensis species subgroup without barbels, and (2) the O. barnoides species subgroup with one or two pairs of barbels. Opsarius putaoensis sp. nov. is a member of the O. chatricensis species subgroup together with O. chatricensis, O. arunachalensis, and O. barna. Opsarius putaoensis is most similar to O. chatricensis in overall appearance, including the number of vertical bars and color pattern, but it differs from O. chatricensis by the following characters: insertion of dorsal not reaching posterior end of pelvic fin base vs. reaching, vertical bars 6-7 vs. 7-8, vertical bars extending to the lateral line vs. not, branched anal-fin rays 9 vs. 10, branched pelvic-fin rays 7 vs. 8, branched pectoral-fin rays 12, rarely 11 vs. 11, circumpeduncular scales 12 vs. 14, and scale rows between dorsal-fin origin and lateral line 7-8 vs. 6. It is distinguished from all other species of the genus Opsarius by a combination of the following characters: barbels absent, dentary with parallel rows of tubercles, snout much shorter than eye diameter, mouth gape below anterior edge of orbit, body deep with depth 25.6-33.3% SL, pectoral and pelvic axial scales lobate, lateral line completely perforated with 35-38 scales, scale rows between dorsal-fin origin and lateral line 7-8, predorsal scales 15, circumpeduncular scales 12, branched dorsal-fin rays 7, branched anal-fin rays 9, branched pelvic-fin rays 7, insertion of dorsal not reaching pelvic-fin base, body with 6-7 vertical bars, extending to lateral line, and distal edge of dorsal fin black.

[Description of two new species and revision of Schizothorax distributed in the Irrawaddy drainage area in China].

The Irrawaddy River crosses international borders throughout South-Eastern Asia, though several heads of different streams connected to the river are found in China. In the present study, two species never previously described were identified during taxonomic works on Schizothorax species distributed in the Irrawaddy drainage area in China, and were named Schizothorax leukus sp. nov. and Schizothorax heteri sp. nov. Schizothorax leukus can be distinguished from its congeners by a combination of the following characters: surface of lower lip covered with papilla, posterior edge of lower lip straight; low jaw developed, almost full the oral cavity, anterior edge of low jaw covered with horny sheath; breast and belly before pectoral-fin tip scaleless; barbels equal to eye diameter; last un-branched dorsal fin ray soft, lower third of the ray enlarged with posterior edge serrated; lateral line scales 94-105, scales between dorsal-fin origin to lateral line 26-34, scales between pelvic-fin origin to lateral line 21-27; outer side of the first gill arch with 16-20 gill rakers; body dark brown, without dark spots. Schizothorax heteri can be distinguished from its congeners by a combination of the following characters: rostral fold equal to upper lip; lower lip developed, trilobed, the median lobe minute, its width equal to diameter of the rostral barbel base; postlabial groove continuous; low jaw without horny sheath; breast and belly before pectoral-fin tip scaleless; barbels equal to eye diameter; last un-branched dorsal fin ray strong, posterior edge serrated; dorsal-fin origin posterior to pelvic-fin origin; lateral line scales 89-104, scales between dorsal-fin origin to lateral line 24-33, scales between pelvic-fin origin to lateral line 19-29; body light brown, without any spots. Likewise, we discuss the validation of S. rotundimaxillaris and the questionable records of S. molesworthi, S. griseus and S. paoshanensis. In total, eight valid species of Schizothorax were found and recorded from the Chinese Irrawaddy drainage area, with a key for identification is provided.

[Sinocyclocheilus xichouensis, a new species of golden-line fish from the Red River drainage in Yunnan, China (Teleostei: Cypriniformes)].

In the present study, a new species of the genus Sinocyclocheilus Fang 1936, Sinocyclocheilus xichouensis, was described from the Ganhaizi tributary of Chouyang River, Red River drainage, located in southeast Yunnan, China. This species has normal eyes and a strong dorsal spine with serrations on the lower 3/5 part. In general, this species is similar in morphology to S. macrophthalmus, S. guishanensis, S. angustiporus, S. lateristritus, S. qiubeiensis, S. grahami, S. qujingensis, S. maculatus and S. purpureus distributed in the Nanpanjiang River, and S. qiubeiensis distributed in the Red River. It is distinguished from S. macrophthalmus by possessing fewer than 9 gill rakers. However, S. xichouensis can be distinguished from S. guishanensis by its interorbital width/SL of 8.1~9.9%, rostral barbels extended to posterior margin of eye and maxillary barbels extended to posterior preopercular. It is distinct from S. lateristritus by dorsal-fin origin opposite of pelvic fin origin, with no a black stripe along the lateral line. It is distinguished from S. grahami by 74~88 lateral-line scales, 20 scale rows above the lateral line, and 16 scale rows below the lateral line. It is distinguished from S. qujingensis by a curved lateral line, 74-88 lateral-line scales, 48 circumpeduncular scales. It can be distinguished from S. yimenensis by the ratio of predorsal length, dorsal-fin base length, preanal length, anal fin length, prepectoral length, caudal-peduncle length and lower jaw length to SL, 47.1%-53.7%, 12.8%-15.8%, 66.0%-71.0%, 13.7%-17.1%, 26.0%-29.5%, 19.3%-24.7%, 4.7%-7.0%, respectively. It is distinguished from S. maculatus and S. purpureus by possession of lateral line and scaled body and distinguished from S. angustiporus and S. qiubeiensis by 35~39 predorsal scales, 6 gill rakers, and interorbital width/SL of 8.1%-9.9%.

[Artificial propagation and embryonic development of Neolissochilus benasi].

From 2009 to 2011, luteinizing hormone releasing hormone analogue (LHRH-A2) mixed with domperidon (DOM) was successfully applied during the artificial propagation of Neolissochilus benasi. Totally, 60 females and 100 males were injected with the hormone mixture, resulting in 47 (78.3%) females and 92 (92.0%) males being successfully spawned. A total of 1,986-5 854 eggs were spawned per female with an egg diameter varying between 2.2-2.8 mm, and an average nucleus deviation rate of 73.2%. Sperm density, vitality and life span were 16.32±2.89×10(9)/mL, 60.6±3.2% and 70.2±5.3 s, respectively. On the whole, the embryonic development of N. benasi was similar to that of zebra fish-albeit relatively slower-lasting approximately 120 hours. The development itself can be divided into six discrete stages: zygote, cleavage, blastula, gastrula, segmentation and hatching. Results showed that the average hatching rate was 32.4%, with 86.5% of larvae surviving 45 days after hatching. During embryonic development, deformities commonly occurred on the mouth, chest, ocular region, especially in the spinal column. To try to attempt improving future breeding efforts, we provided a survey of the embryonic developmental difficulties of N. benasi using LHRH-A2 followed by several potential solutions, including providing suitable breeding conditions and minimizing capture stresses.