A note on the genus Pseudathyma Staudinger with description of a new species (Lepidoptera: Nymphalidae)

Summary

A note is given on the status of Pseudathyma callina Grose-Smith and Pseudathyma sybillina Staudinger. A new species is described, and one name synonymized.     

Lake Tanganyika as an evolutionary reservoir of old lineages of East African cichlid fishes: Inferences from allozyme data

Genetic differences between 20 species of cichlid fish, representing all the 12 tribes proposed for the cichlid fish fauna of Lake Tanganyika, were studied by allozyme electrophoresis. Most species were genetically very differentiated from each other. Phylogenetic analysis based on the allozyme data indicated that at least seven old, ancestral lineages have contributed to the present cichlid fauna of the lake. Lake Tanganyika, the oldest of the rift-valley lakes, can be recognized as an evolutionary reservoir of major lineages of cichlids in East Africa.     

Tanganyika盆地南部地震相识别及沉积演化分析

东非裂谷系盆地近年来不断取得油气发现,Tanganyika盆地与已发现含油气盆地构造及沉积特征相似,具有较大的勘探潜力。本次研究根据地震反射界面接触关系及界面上下地震反射特征,识别出4个层序界面：T14、T12、T5、T2,相应地将盆地沉积地层划分为4个三级层序：SQ1-SQ4。在层序格架控制下,根据地震相外部反射形态及内部反射结构,识别出河道充填状、强振幅席状、弱振幅席状、楔状、透镜状、丘状、叠瓦状共7种地震相类型,反映河流、滨浅湖-深湖、深水等深流、扇三角洲等不同沉积体系。结果表明研究区SQ1层序时期,缓坡带孤立半地堑发育三角洲沉积,洼陷中心以滨浅湖-深湖相沉积为主;SQ2层序时期缓坡带作为统一的构造单元发育河流及三角洲沉积,洼陷中心以发育三角洲及浊流相沉积为特征;SQ3层序时期构造抬升,缓坡带发育大型曲流河沉积,洼陷中心三角洲及浊流沉积规模进一步扩大;SQ4层序时期裂陷进一步加剧,洼陷中心发育洼陷中心发育深水等深流沉积,边界断层陡坡带发育大规模扇三角洲及滑塌沉积。     

A revision of the genus Platythelphusa A. Milne-Edwards, 1887 from Lake Tanganyika,East Africa (Decapoda: Potamoidea: Platythelphusidae)

The genus Platythelphusa is revised and six species are recognized. These species are P. armata A. Milne-Edwards, 1887, P. maculata (Cunnington, 1899), P. conculata Cunnington, 1907, P. tuberculata Capart, 1952, P. polita Capart, 1952 and P. echinata Capart, 1952. A seventh taxon, P. denticulata Capart, 1952 is considered here to be a junior synonym of P. conculata. A diagnosis for each species is provided and most are figured from the type. Keys to the families of African freshwater crabs and to the genus Platythelphusa are also provided.