The balance of vitamin B12 in massculture of the rotifer Brachionus plicatilis was calculated for both batch and semicontinuous cultures after the evaluation of B12 concentrations in Nannochloropsis, yeast, rotifer and culture water.The B12 output, which is taken as the total of B12 harvested and left remaining in a tank, was 1.6-2.2 times larger than the B12 introduced with food, water and inoculum.On the other hand, among 100 bacterial strains isolated from rotifer tanks, 35 had B12 productivity and 19 of them promoted the growth of the rotifer effectively when supplied with yeast.Calculated from the feeding rate, the B12 content of bacteria and the B12 demand of the rotifer, it is proved that the greater part of B12, the essential vitamin to the rotifer is produced by bacteria existing in water, and excess amount was transferred to the rotifer automatically by grazing.

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Flagship species have been used widely as umbrella species (i.e., species with large home range whose protection often provides protection for sympatric species) in the management of China's nature reserves. This conflation of flagship and umbrella species is best represented by the giant panda (Ailuropoda melanoleuca) and other large, endangered mammals designated as conservation targets in site selection and planning of reserves. Few empirical studies have tested the effectiveness of flagship species as surrogates for a broader range of sympatric species. Using extensive camera-trap data, we examined the effectiveness of management zones designated to protect flagship (target) species in conserving sympatric species in 4 wildlife reserves (Gutianshan, Changqing, Laohegou, and Wolong). We tested whether the progression from peripheral to core zones was associated with an increasing habitat association for both target and sympatric species. The distribution patterns of the study species across the zones in each reserve indicated a disparity between management zones and the species' habitat requirements. Management zone was included in the final model for all target species, and most of them had higher occurrence in core zones relative to less-protected zones, but zone was not a predictor for most of the sympatric species. When management zone was associated with the occurrence of sympatric species, threatened species generally had higher detections in core zones, whereas common species had higher detections outside of the core zone. Our results suggested that reserve planning based on flagship species does not adequately protect sympatric species due to their specialized habitat requirements. We recommend re-examining the effectiveness of management zoning and urge a multispecies and reserve-wide monitoring plan to improve protection of China's wildlife. Efectividad del Manejo de Zonación Diseñada para Especies Bandera en la Protección de Especies SimpátricasResumen: Las especies bandera se han utilizado ampliamente como especies paraguas (es decir, especies con una extensa distribución cuya protección frecuentemente proporciona protección para especies simpátricas) en el manejo de las reservas naturales de China. Esta combinación de especie bandera y especie paraguas tiene su mejor representación en el panda gigante (Ailuropoda melanoleuca) y otros grandes mamíferos en peligro de extinción designados como objetivos de conservación en la selección de sitio y la planeación de reservas. Pocos estudios empíricos han probado la efectividad de las especies bandera como sustitutas de una especie simpátrica * Address correspondence to Keping Ma, email kpma@ibcas.ac.cn †Both the authors contributed equally to this article. Article impact statement: Zoning designations in China's wildlife reserves aimed at conserving flagship species may not meet the habitat needs of most sympatric species.

The white-lipped tree viper, Trimeresurus albolabris Gray, is one of the most common species of the genus Trimeresurus with a wide distribution from India eastwards to China and southwards to Indonesia. However, this species was previously split into five geographical clades with significant genetic divergence. Recent surveys in Yingjiang County, Yunnan Province, China resulted in the discovery of one cryptic species of the subgenus Trimeresurus. Combining molecular, morphological and ecological data, we describe it as a new species Trimeresurus caudornatus sp. nov. The new species differs from other Trimeresurus species by a combination of the following characteristics: (1) Head and body generally dark green, postocular stripes absent in both genders, upper labials light green; (2) ventrolateral stripe faint green yellow, present on the first row of DSR in both genders; (3) iris golden yellow in both genders; (4) dorsal tail mostly dark red, lateral and ventral green; an orange red stripe along the ventral part of the tail; (5) DSR 21/22 –21–15, VEN 161–163, SC 52–72; (6) first upper labial partially fused to the nasal. The new species was shown to be a strongly supported monophyletic group (BPP 100%) and sister to T. septentrionalis. The uncorrected pairwise distances of mitochondrial gene Cytb between the new species and other species of the subgenus Trimeresurus, ranging from 0.059 (T. septentrionalis) to 0.134 (T. kanburiensis).

1. Positive relationships between structural diversity and forest productivity have been documented in controlled experiments and early secondary forests, however, negative relationships have also been observed in late successional forests.The mechanisms causing observed relationships between structural diversity and productivity are not well-established, but complementarity among crowns and asymmetric competition have been suggested.2. We used LiDAR and repeated census data to examine the relationship between canopy structural diversity and productivity in nine 1-ha subtropical forest plots along a disturbance gradient in southeastern China. We quantified the relative importance of community composition, species diversity, canopy structural diversity, leaf area index (LAI) and disturbance regime on productivity using piecewise structural equation modelling. We also tested how vertical leaf area distribution affected productivity.3. Contrary to many prior observations, we found a negative relationship between canopy structural diversity and forest productivity. The negative effect may stem from asymmetric competition between overstorey and understorey leaves, leading to a lower leaf area efficiency (i.e. wood production per leaf area). Asymmetric competition was suggested by a negative relationship between understorey leaf area and total productivity. Changes in community composition over the disturbance gradient, but not species diversity, had a significant effect on productivity.4. Synthesis. Our study suggests that leaf area and canopy structural diversity have contrasting effects on productivity in this subtropical forest, and this needs to be considered when estimating rates of carbon sequestration in secondary forests.The negative effect of asymmetric competition on productivity is comparable to that of the shift in species composition over succession, highlighting the role of canopy structural diversity in shaping forest productivity.