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New palm leaves from the Oligocene Ningming Formation are placed into the morphogenusSabalitesbecause of their costapalmate leaf shape. Four taxa are described on the basis of leaf compressions with cuticular structure.S. guanxiensissp. nov. is characterised by hypostomatic leaf blades with a stout costa and a symmetrical base.Sabalitescf.asymmetricushas amphistomatic leaf blades with a long, delicate costa and an asymmetrical base.Sabalitessp. 1 has amphistomatic leaf blades with a long, massive costa and wide segments.Sabalitessp. 2 is characterized by hypostomatic leaf blades with a prominent costa and an asymmetrical base. The four new palm taxa expand our understanding of the floristic elements and features of the Oligocene Ningming flora. Together with the other three palm taxa that were previously reported from the Ningming Formation, our material indicates that the Oligocene Ningming flora had a rich diversity of costapalmate palms. The relatively high species diversity of palms and other plants corroborate that the Oligocene Ningming flora represents a warm and humid climate. [ABSTRACT FROM PUBLISHER]

A new fossil species ofZelkovais described from the Oligocene Ningming Formation of Guangxi, South China.Zelkova ningmingensissp. nov.is characterized by leaves with craspedodromous venation pattern and drupaceous fruit type. The new species possesses elliptical to ovate leaves, bearing 7–12 pairs of secondary and simple toothed margin, as well as epidermal cells with straight or rounded anticlinal walls. The species is compared with extant and other fossil species hitherto reported of the genus. It is most similar to the livingZelkova schneiderianain the leaf gross morphology and epidermal characters, which may be suggested to be the ancestral type ofZelkova schneideriana. The discovery ofZelkova ningmingensissp. nov.in Guangxi indicates thatZelkovahas already existed in southern China as early as the Oligocene. In combination withZelkovamaterial from the Oligocene of Europe, it can be inferred that EurasianZelkovahad begun to diversify by at least the Oligocene. Because China is the biodiversity centre of modernZelkova, the fossil herein provides new insights intoZelkovabiogeography. [ABSTRACT FROM AUTHOR]

Mussels have been proposed as appropriate biomonitors of marine pollution, especially for monitoring metallic pollution based on variations of metallothionein as biomarkers. Under 2 exposure levels (12.7 microg/L, 63.5 microg/L), Cu accumulation and metallothionein-like protein (MTLP) induction by mussel (Perna viridis) digestive glands were investigated and simulated into dynamic models in the present work, and the soluble and total Cu burden of digestive glands were also determined. Calculated mean Cu uptake rates by mussel target organ were 2.045 and 7.028 microg x (g x d)(-1) respectively, and the theoretical equilibrium kinetic BCFs of Cu were 2074 and 1619 correspondingly. And within the exposure duration, different changing trends of ratio of soluble Cu to total Cu in digestive glands were observed in the two groups. The MTLP level of control samples was (0.551 +/- 0.037) mg/g, and the counterparts are 0.407 - 0.699 mg/g, 0.826 - 0.942 mg/g respectively when mussels were exposed to 12.7 microg/L and 63.5 microg/L Cu solutions. Statistically significant MTLP induction (p < 0.001) was observed under higher exposure level. MTLP contents in digestive glands increased with the exposure Cu concentration and body accumulation of metal. There is a significantly negative exponential rise relationship (p < 0.000 1) between MTLP and Cu concentrations accumulated in the digestive glands of mussels.