A new genus and species of eutriconodont mammal,Chaoyangodens lii gen.et sp.nov.,from the Dawangzhangzi bed of Yixian Formation,Lingyuan,Liaoning,is reported.The new species has a tooth formula I5-C1-P1-M3/i4-c1-p1-m4...A new genus and species of eutriconodont mammal,Chaoyangodens lii gen.et sp.nov.,from the Dawangzhangzi bed of Yixian Formation,Lingyuan,Liaoning,is reported.The new species has a tooth formula I5-C1-P1-M3/i4-c1-p1-m4,unique among eutriconodonts in having only one premolar in lower and upper jaws,respectively,and a distinctive diastema between the canine and the premolar.Its simple incisors and reduced premolars show a mosaic combination of primitive and derived features.This new taxon adds to the diverse group of Jehol eutriconodonts.Among the known species from at least three horizons,there seems no evolutionary trend in morphology that is recognizable,except for that larger species are all from the Lujiatun bed of the Yixian Fm.A thorough and systematic analysis involving all the Jehol eutriconodonts is needed to understand their phylogenetic relationships.展开更多
基金supported by the National Basic Research Program of China(2012CB821906)Public Science and Technology Research Funds Projects of Land and Resources(201311120)+1 种基金the National Natural Science Foundation of China(41202014)the American Museum of Natural History,New York
文摘A new genus and species of eutriconodont mammal,Chaoyangodens lii gen.et sp.nov.,from the Dawangzhangzi bed of Yixian Formation,Lingyuan,Liaoning,is reported.The new species has a tooth formula I5-C1-P1-M3/i4-c1-p1-m4,unique among eutriconodonts in having only one premolar in lower and upper jaws,respectively,and a distinctive diastema between the canine and the premolar.Its simple incisors and reduced premolars show a mosaic combination of primitive and derived features.This new taxon adds to the diverse group of Jehol eutriconodonts.Among the known species from at least three horizons,there seems no evolutionary trend in morphology that is recognizable,except for that larger species are all from the Lujiatun bed of the Yixian Fm.A thorough and systematic analysis involving all the Jehol eutriconodonts is needed to understand their phylogenetic relationships.
