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Global eutrophication and climate warming exacerbate production of cyanotoxins such as microcystins (MCs), presenting risks to human and animal health. Africa is a continent suffering from severe environmental crises, including MC intoxication, but with very limited understanding of the occurrence and extent of MCs. By analysing 90 publications from 1989 to 2019, we found that in various water bodies where MCs have been detected so far, the concentrations were 1.4–2803 times higher than the WHO provisional guideline for human lifetime exposure via drinking water (1 µg/L) in 12 of 15 African countries where data were available. MCs were relatively high in the Republic of South Africa (averaged 2803 μg/L) and Southern Africa as a whole (702 μg/L) when compared to other regions. Values were higher in reservoirs (958 μg/L) and lakes (159 μg/L) than in other water types, and much higher in temperate (1381 μg/L) than in arid (161 μg/L) and tropical (4 μg/L) zones. Highly significant positive relationships were found between MCs and planktonic chlorophyll a. Further assessment revealed high ecological risk for 14 of the 56 water bodies, with half used as human drinking water sources. Recognizing the extremely high MCs and exposure risk in Africa, we recommend routine monitoring and risk assessment of MCs be prioritized to ensure safe water use and sustainability in this region.

Both eutrophication and salinization are growing global environmental problems in freshwater ecosystems, threatening the water quality and various aquatic organisms. However, little is known about their interactive effects on theses stressors and the role of lake depth on these interactions. We used field surveys to compared zooplankton assemblages over four seasons in eight Yunnan Plateau lakes with different trophic states, salinization levels, and water depths. The results showed that: 1) the species number (S), density (DZoop), and biomass (BZoop) of zooplankton exhibited strong seasonal dynamics, being overall higher in the warm seasons. 2) Data collected over four seasons and summer data both revealed highly significant positive relationships of S, DZoop, and BZoop with total nitrogen (TN), total phosphorus (TP), and phytoplankton chlorophyll a (Chl a). 3) S, DZoop, and BZoop displayed a unimodal relationship with salinity, peaking at 400–1000 μS/cm (conductivity, to reflect salinity). 4) The two large-sized taxa (cladocerans and copepods) generally increased at low-moderate levels of TN, TP, Chl a, and Cond and was constant or decreased at high levels. The average body mass (biomass/density) of crustaceans decreased with increasing TN, TP, Chl a, and conductivity. Our findings indicate that zooplankton may be more vulnerable in deep lakes than in shallow lakes when exposed to conductivity stress even under mesotrophic conditions, and the overall decrease in size in zooplankton assemblages under the combined stress of eutrophication and salinization may result in a lowered grazing effect on phytoplankton.

Eutrophication and salinization are serious global environmental problems in freshwater ecosystems, occasionally acting jointly to exert harmful effects on aquatic ecosystems. To elucidate the interactive effects of nutrients and salinity on phytoplankton assemblages, we conducted a four-season study during 2020–2021 of eight lakes from Yunnan Plateau (Southwest China) with a wide range of conductivities (Cond, reflecting degree of salinization), eutrophic states, and water depths and used General Additive Modeling (GAM) of the data. We found that: (1) species number (SN), density (DPhyt), and biomass (BPhyt) of phytoplankton showed stronger seasonal dynamics in shallow lakes than in deep lakes, all being, as expected, higher in the warm season; (2) annual and summer data revealed highly significant positive relationships between SN, DPhyt, and BPhyt with total nitrogen (TN) and total phosphorus (TP), which became weaker at high TP occurring when the N:P ratio was low, indicating N limitation; (3) SN, DPhyt, and BPhyt showed a unimodal relationship with salinity, peaking at 400–1000 μS/cm (Cond); (4) the two dominant taxa (cyanobacteria and chlorophyta) showed different patterns, with chlorophyta generally dominating at low TN and cyanobacteria at high TN and Cond, suggesting the synergistic effect of nitrogen and Cond on cyanobacterial dominance.

Key to the species of Oxyporus of Yunnan Province 1 Body entirely black; known from Baoshan ......................................................................................................... O. femoratus Zheng - Body bicolor...................................................................................................................................................................................... 2 2 Head black to brownish black…………………............................................................................................................................... 3 - Head yellow to reddish yellow.......................................................................................................................................................... 8 3 Maximum length more than 9 mm................................................................................................................... ……………….........4 - Maximum length no more than 9 mm............................................................................................................................................... 5 4 Pronotal disc without transverse depression; known from Lijiang ...................................................................... O. germanus Sharp - Pronotal disc with 1 deep, transverse depression located just before middle; known from Mojiang .............. O. wangae sp. nov. Li 5 Abdomen brownish yellow, with two longitudinal black fasciae on tergites 3–7; known from Binchuan ....... O.bifasciarius Zheng - Abdomen without black longitudinal fasciae.................................................................................................................................... 6 6 Abdominal tergites 3–4 or 3–5 yellow to reddish yellow; known from Dali ......................................................... O. riparius Zheng - Abdominal tergites 3–4 or 3–5 black................................................................................................................................................ 7 7 Elytra with black area in basal part of suture; pronotal disc bearing 2 vague longitudinal depressiions in middle just behind the transverse depression; know from Lijiang ....................................................................................... O. transversesulcatus Bernhauer - Elytra without black area in basal part of suture, pronotal disc bearing 3 vague longitudinal depressiions in middle just behind the transverse depression; known from Kunming ......................................................................................................... O. kunmingius Li 8 Abdominal segments 3–5 black; known from Lijiang............................................................................................. O. yulong Zheng - Abdominal segments 3–5 brownish yellow to reddish yellow.......................................................................................................... 9 9 Posterior portion of gula and metasternum brownish yellow; known from Puer............................................................ O. lii Zheng - Posterior portion of gula and metasternum reddish yellow............................................................................................................. 10 10 Pronotal anterior without macula, disc with 2 deep, transverse depressions before middle; known from Puer ............ O. puerius Li - Pronotal anterior 1/2 bearing a black small subquadrate macula, disc with 1 deep, transverse depressions before middle; known from Mojiang .......................................................................................................................................................... O. bingshengae Li

Key to the species of Oxyporus of Yunnan Province 1 Body entirely black; known from Baoshan ......................................................................................................... O. femoratus Zheng - Body bicolor...................................................................................................................................................................................... 2 2 Head black to brownish black���������������������............................................................................................................................... 3 - Head yellow to reddish yellow.......................................................................................................................................................... 8 3 Maximum length more than 9 mm................................................................................................................... ������������������.........4 - Maximum length no more than 9 mm............................................................................................................................................... 5 4 Pronotal disc without transverse depression; known from Lijiang ...................................................................... O. germanus Sharp - Pronotal disc with 1 deep, transverse depression located just before middle; known from Mojiang .............. O. wangae sp. nov. Li 5 Abdomen brownish yellow, with two longitudinal black fasciae on tergites 3���7; known from Binchuan ....... O.bifasciarius Zheng - Abdomen without black longitudinal fasciae.................................................................................................................................... 6 6 Abdominal tergites 3���4 or 3���5 yellow to reddish yellow; known from Dali ......................................................... O. riparius Zheng - Abdominal tergites 3���4 or 3���5 black................................................................................................................................................ 7 7 Elytra with black area in basal part of suture; pronotal disc bearing 2 vague longitudinal depressiions in middle just behind the transverse depression; know from Lijiang ....................................................................................... O. transversesulcatus Bernhauer - Elytra without black area in basal part of suture, pronotal disc bearing 3 vague longitudinal depressiions in middle just behind the transverse depression; known from Kunming ......................................................................................................... O. kunmingius Li 8 Abdominal segments 3���5 black; known from Lijiang............................................................................................. O. yulong Zheng - Abdominal segments 3���5 brownish yellow to reddish yellow.......................................................................................................... 9 9 Posterior portion of gula and metasternum brownish yellow; known from Puer............................................................ O. lii Zheng - Posterior portion of gula and metasternum reddish yellow............................................................................................................. 10 10 Pronotal anterior without macula, disc with 2 deep, transverse depressions before middle; known from Puer ............ O. puerius Li - Pronotal anterior 1/2 bearing a black small subquadrate macula, disc with 1 deep, transverse depressions before middle; known from Mojiang .......................................................................................................................................................... O. bingshengae Li, Published as part of Li, Guo-Feng, Wang, Chun-Mei, Li, Hua-Feng, Li, Zhi-Gang & Huang, Pu-Ze, 2017, A new species of the genus Oxyporus Fabricius (Coleoptera: Staphylinidae: Oxyporinae) in Yunnan Province, China, pp. 588-592 in Zootaxa 4268 (4) on page 591, DOI: 10.11646/zootaxa.4268.4.10, http://zenodo.org/record/581006

Oxyporus (Oxyporus) wangae sp. nov. (Figs. 1 A���B, Figs. 2 A���E) Type material. Holotype: CHINA: Yunnan Province.: ♂, Mojiang County, Tuan tian village, alt. 1857m, 23��36���N, 101��17���E, 23���31-July-2016, Wang Chun-mei leg. Paratypes: CHINA: Yunnan Province: 1♂, same data as the Holotype (YFTC). Description. BL: 10.18 mm, FBL: 3.18 mm, ML: 1.64 mm, HL: 1.64 mm, HW: 2.22 mm, TL: 0.84 mm, AL: 1.71 mm, LW: 0.83 mm, PL: 1.50 mm, PW: 1.98 mm, ELL: 2.05 mm, ELW: 2.83 mm, EYL: 0.78 mm. Body moderately stout, surface almost smooth and glossy. Color reddish yellow, with mandibles, head, pronotum, scutellum, abdomen (except segments 3���4 and sides of segments 5���6) black, each elytra bearing subtriangular black marking at outer apical angle extending from the posterior 1/2 of lateral margin to middle of posterior margin and ending near suture by narrow black fascia along posterior margin.. (Figs. 1 A). Male: Head oval, wider than long (ratio 1.35), broader than pronotum (ratio 1.12), slightly widened posteriad behind eyes, posterior angles obtuse. Mandibles as long as head, moderately broad, inner edges evenly curved to acute apices. Labrum broadly and deeply emarginate at middle. Clypeus broadly and shallowly emarginate at middle. Maxillary palpi with first segment shortest, second longer than third, third slightly wider than last and almost equal in length, and apical segment of labial palpi slightly wider than length of an eye (ratio 1.06). Frons broadly, shallowly bi-impressed between antennal insertions; Antennae slightly longer than head (ratio 1.04); segments 1���4 elongate, 5���10 transverse, slightly asymmetrical and flattened, apical segment narrower than preceding segment, each segment with long setae near apex, and segments 5���10 glabrous medially and covered with fine setae laterally, the relative length of segments from base to apex as 0.25: 0.13: 0.18: 0.15: 0.14: 0.15: 0.13: 0.14: 0.14: 0.13: 0.20. Eyes large and convex. Vertex nearly smooth, two setiferous punctures near inner margin of eye, one anteriad and one posteriad. Temples slightly longer than eyes seen from above (ratio 1.08). Pronotum subhexagonal, slightly transverse, wider than long (ratio 1.35), shorter (ratio 0.73) and narrower (ratio 0.70) than elytra, lateral margins arcuate at about anterior 1/3 and subarcuately narrowed posteriad, widest at about anterior 1/3; disc almost impunctate, devoid of microsculpture, with 1 deep, transverse depression located just before middle, which is widened to both sides, and additionaly, surface bearing 2 vague longitudinal depressions in middle just behind the transverse depression, which does not reach to posterior margin, and each lateral side with 1 fovea in the middle; 8 setiferous punctures bearing at anterior margin, 4 ones at each lateral margin. Scutellum impunctate, rounded at apex, surface almost smooth. Elytra wider than long (ratio 1.38), slightly widened apicad; each elytron with 1 row of evenly spaced small punctures along suture, 2 longitudinal rows of coarse variably spaced punctures medially, and several, scattered coarse punctures to either side of rows; apical, lateral, and posterior margins bearing a few short setae; humeri produced forward and convex above. Hind Wings developed. Abdomen with tergites 3���4 each with a pair of pruinose spots at middle and tergites 3���6 each with 1���3 irregular setiferous punctures along lateral margin; punctation of tergites very sparse and vague, surface between punctures with exceedingly fine and dense microsculpture of transverse striae; posterior margins of sternites 7 slightly and broadly emarginated at middle but posterior margins of sternites 8 strongly and broadly emarginated at middle. (Fig. 1 B) Aedeagus slightly asymmetrical and moderately sclerotized; median lobe somewhat widened apicad and slightly narrowed in middle, with apical margin rounded; parameres relatively long and slender, gradually narrowed apicad, (Figs. 2 A���C); the right lobe and left lobe without minute seta at each apex. (Figs. 2 D���E) Female: Unknown. Remarks. Oxyporus wangae n. sp. is similar to O. germanus Sharp from Lijiang City (Yulongxueshan Natural Reserve), Yunnan Province, China, in the color of the body, but can be distinguished from the latter by the following characters (see key below): elytra without a slightly broad black fascia along full length of suture; apical portion of abdominal tergite 8 orange yellow; right and left paramere without minute seta at each apex. Etymology. The specific epithet is patronymic in honor of the collector of the Holotype, WANG Chun-Mei. Habitat and distribution. The new species was found in fungi. It is at present only known from the type locality in southwest Yunnan Province, China., Published as part of Li, Guo-Feng, Wang, Chun-Mei, Li, Hua-Feng, Li, Zhi-Gang & Huang, Pu-Ze, 2017, A new species of the genus Oxyporus Fabricius (Coleoptera: Staphylinidae: Oxyporinae) in Yunnan Province, China, pp. 588-592 in Zootaxa 4268 (4) on pages 589-591, DOI: 10.11646/zootaxa.4268.4.10, http://zenodo.org/record/581006