The micromammal fossils collected from the Shangzhuang Formation of the Linxia Basin,Gansu,are described here.The assemblage consists of 16 species of 13 genera belonging to 7 families,including one new species and on...The micromammal fossils collected from the Shangzhuang Formation of the Linxia Basin,Gansu,are described here.The assemblage consists of 16 species of 13 genera belonging to 7 families,including one new species and one taxon previously unknown from China.Among them 5 genera are Oligocene holdovers and 11 genera/species are known to make their first appearances in Early Miocene,indicating an Early Miocene age for the Gucheng Fauna.The absence of Oligocene survivors such as Tataromys,Yindirtemys,Eucricetodon and Tachyoryctoides,which usually occur in the Xiejian age of Early Miocene,and the presence of newcomers Protalactaga,Megacricetodon and Gobicricetodon,that made their first appearance only in the Shanwangian age of late Early Miocene,suggest that the Gucheng Fauna is of a later age of Early Miocene.The new species,Sinolagomys guchengensis,showing more derived morphology than in S.ulunguensis,seems to support an assessment of the fauna in Shanwangian age.Thus,the Gucheng Fauna may belong to late Early Miocene Shanwangian,partially equivalent to MN 3/4 of the European land mammal zonation.Ecological analysis of the fauna indicates that the palaeoecological condition of the Gucheng area might still be a predominantly arid shrub-steppe in late Early Miocene.展开更多
Suid is one of the most common taxa among the Pleistocene mammalian fauna in China.However,its phylogenetic taxonomy and evolution are far from clear.The newly recovered suid fossil materials from the Early Pleistocen...Suid is one of the most common taxa among the Pleistocene mammalian fauna in China.However,its phylogenetic taxonomy and evolution are far from clear.The newly recovered suid fossil materials from the Early Pleistocene Shanshenmiaozui site in Nihewan Basin in North China provide new insight into the evolution of its kind in North China.The new materials include partial skulls and mandibles of males,and most of their teeth were preserved in situ.The specimens can be referred to the species Sus lydekkeri,which is the only species of Sus found in North China from the Early Pleistocene.The fossils of the once reported Pleistocene species“Potamochoerus chinhsienensis”should also be provisionally included in the species S.lydekkeri according to its form and size,which at least now excludes it from Potamochoerus.The species S.lydekkeri is very close to the extant species S.scrofa,and even was combined into the latter as a chronological subspecies by some authors,while its larger size,prominent preorbital fossa,backwardly positioned infraorbital foramen,frequently appearing verrucosic type(at least the intermediate type of the male lower canine),and simple crown structures support its validness as an independent species.The Early Pleistocene forms are characterized by a larger size,lower L/W ratio of cheekteeth,both upper and lower M3s having no more than three lobes,and the male lower canine is exclusively of a verrucosic type.Suid fossils are a very good indicator of paleoenvironments and paleoclimate.Both the northern and the southern faunas in China contain suid fossils throughout the Pleistocene Epoch,while the southern fauna has prominently more diversified taxa and more abundant fossil collections;whether that is caused by different origins or by environmental modifications is still not clear.展开更多
Perleididae is a group of stem neopterygian fishes known only from the Triassic.Here,we report the discovery of a new perleidid,Teffichthys wui sp.nov.,based on six well-preserved specimens from the late Smithian(Olen...Perleididae is a group of stem neopterygian fishes known only from the Triassic.Here,we report the discovery of a new perleidid,Teffichthys wui sp.nov.,based on six well-preserved specimens from the late Smithian(Olenekian,Early Triassic)marine deposits of Jurong,Jiangsu and Chaohu,Anhui,China.This new discovery documents the third and youngest species of Teffichthys,which is slightly younger than the Dienerian(Induan)T.elegans from Guizhou and the early Smithian T.madagascariensis from Madagascar.The new species shows diagnostic features of Teffichthys(presence of a spiracular,38-41 lateral line scales,and no more than three epaxial rays in the caudal fin)but differs from T.madagascariensis and T.elegans in some autapomorphies(e.g.,a horizontal opercle/subopercle contact and smooth scales with a nearly straight posterior margin).The diagnostic features for the genus Teffichthys and the family Perleididae are emended based on detailed comparisons of the new taxon with other perleidids.The phylogenetic relationships of perleidids with other stem neopterygians are discussed using a cladistic approach,and the results provide new insights into the phylogeny and classification of main stem neopterygian clades.展开更多
Background Globally,the cultivation of cotton is constrained by its tendency for extended periods of growth.Early maturity plays a potential role in rainfed-based multiple cropping system especially in the current era...Background Globally,the cultivation of cotton is constrained by its tendency for extended periods of growth.Early maturity plays a potential role in rainfed-based multiple cropping system especially in the current era of climate change.In the current study,a set of 20 diverse Gossypium hirsutum genotypes were evaluated in two crop seasons with three planting densities and assessed for 11 morphological traits related to early maturity.The study aimed to identify genotype(s)that mature rapidly and accomplish well under diverse environmental conditions based on the two robust multivariate techniques called multi-trait stability index(MTSI)and multi-trait genotype-ideotype distance index(MGIDI).Results MTSI analysis revealed that out of the 20 genotypes,three genotypes,viz.,NNDC-30,A-2,and S-32 accomplished well in terms of early maturity traits in two seasons.Furthermore,three genotypes were selected using MGIDI method for each planting densities with a selection intensity of 15%.The strengths and weaknesses of the genotypes selected based on MGIDI method highlighted that the breeders could focus on developing early-maturing genotypes with specific traits such as days to first flower and boll opening.The selected genotypes exhibited positive genetic gains for traits related to earliness and a successful harvest during the first and second pickings.However,there were negative gains for traits related to flowering and boll opening.Conclusion The study identified three genotypes exhibiting early maturity and accomplished well under different planting densities.The multivariate methods(MTSI and MGIDI)serve as novel approaches for selecting desired genotypes in plant breeding programs,especially across various growing environments.These methods offer exclusive benefits and can easily construe and minimize multicollinearity issues.展开更多
文摘The micromammal fossils collected from the Shangzhuang Formation of the Linxia Basin,Gansu,are described here.The assemblage consists of 16 species of 13 genera belonging to 7 families,including one new species and one taxon previously unknown from China.Among them 5 genera are Oligocene holdovers and 11 genera/species are known to make their first appearances in Early Miocene,indicating an Early Miocene age for the Gucheng Fauna.The absence of Oligocene survivors such as Tataromys,Yindirtemys,Eucricetodon and Tachyoryctoides,which usually occur in the Xiejian age of Early Miocene,and the presence of newcomers Protalactaga,Megacricetodon and Gobicricetodon,that made their first appearance only in the Shanwangian age of late Early Miocene,suggest that the Gucheng Fauna is of a later age of Early Miocene.The new species,Sinolagomys guchengensis,showing more derived morphology than in S.ulunguensis,seems to support an assessment of the fauna in Shanwangian age.Thus,the Gucheng Fauna may belong to late Early Miocene Shanwangian,partially equivalent to MN 3/4 of the European land mammal zonation.Ecological analysis of the fauna indicates that the palaeoecological condition of the Gucheng area might still be a predominantly arid shrub-steppe in late Early Miocene.
文摘Suid is one of the most common taxa among the Pleistocene mammalian fauna in China.However,its phylogenetic taxonomy and evolution are far from clear.The newly recovered suid fossil materials from the Early Pleistocene Shanshenmiaozui site in Nihewan Basin in North China provide new insight into the evolution of its kind in North China.The new materials include partial skulls and mandibles of males,and most of their teeth were preserved in situ.The specimens can be referred to the species Sus lydekkeri,which is the only species of Sus found in North China from the Early Pleistocene.The fossils of the once reported Pleistocene species“Potamochoerus chinhsienensis”should also be provisionally included in the species S.lydekkeri according to its form and size,which at least now excludes it from Potamochoerus.The species S.lydekkeri is very close to the extant species S.scrofa,and even was combined into the latter as a chronological subspecies by some authors,while its larger size,prominent preorbital fossa,backwardly positioned infraorbital foramen,frequently appearing verrucosic type(at least the intermediate type of the male lower canine),and simple crown structures support its validness as an independent species.The Early Pleistocene forms are characterized by a larger size,lower L/W ratio of cheekteeth,both upper and lower M3s having no more than three lobes,and the male lower canine is exclusively of a verrucosic type.Suid fossils are a very good indicator of paleoenvironments and paleoclimate.Both the northern and the southern faunas in China contain suid fossils throughout the Pleistocene Epoch,while the southern fauna has prominently more diversified taxa and more abundant fossil collections;whether that is caused by different origins or by environmental modifications is still not clear.
文摘Perleididae is a group of stem neopterygian fishes known only from the Triassic.Here,we report the discovery of a new perleidid,Teffichthys wui sp.nov.,based on six well-preserved specimens from the late Smithian(Olenekian,Early Triassic)marine deposits of Jurong,Jiangsu and Chaohu,Anhui,China.This new discovery documents the third and youngest species of Teffichthys,which is slightly younger than the Dienerian(Induan)T.elegans from Guizhou and the early Smithian T.madagascariensis from Madagascar.The new species shows diagnostic features of Teffichthys(presence of a spiracular,38-41 lateral line scales,and no more than three epaxial rays in the caudal fin)but differs from T.madagascariensis and T.elegans in some autapomorphies(e.g.,a horizontal opercle/subopercle contact and smooth scales with a nearly straight posterior margin).The diagnostic features for the genus Teffichthys and the family Perleididae are emended based on detailed comparisons of the new taxon with other perleidids.The phylogenetic relationships of perleidids with other stem neopterygians are discussed using a cladistic approach,and the results provide new insights into the phylogeny and classification of main stem neopterygian clades.
文摘Background Globally,the cultivation of cotton is constrained by its tendency for extended periods of growth.Early maturity plays a potential role in rainfed-based multiple cropping system especially in the current era of climate change.In the current study,a set of 20 diverse Gossypium hirsutum genotypes were evaluated in two crop seasons with three planting densities and assessed for 11 morphological traits related to early maturity.The study aimed to identify genotype(s)that mature rapidly and accomplish well under diverse environmental conditions based on the two robust multivariate techniques called multi-trait stability index(MTSI)and multi-trait genotype-ideotype distance index(MGIDI).Results MTSI analysis revealed that out of the 20 genotypes,three genotypes,viz.,NNDC-30,A-2,and S-32 accomplished well in terms of early maturity traits in two seasons.Furthermore,three genotypes were selected using MGIDI method for each planting densities with a selection intensity of 15%.The strengths and weaknesses of the genotypes selected based on MGIDI method highlighted that the breeders could focus on developing early-maturing genotypes with specific traits such as days to first flower and boll opening.The selected genotypes exhibited positive genetic gains for traits related to earliness and a successful harvest during the first and second pickings.However,there were negative gains for traits related to flowering and boll opening.Conclusion The study identified three genotypes exhibiting early maturity and accomplished well under different planting densities.The multivariate methods(MTSI and MGIDI)serve as novel approaches for selecting desired genotypes in plant breeding programs,especially across various growing environments.These methods offer exclusive benefits and can easily construe and minimize multicollinearity issues.
