摘要
关于西南地区早二叠世苔藓虫的研究报道,早见于上世纪末和本世纪初,但多数是少量标本的报道,如Loczy(1877-1880),Mansuy(1912),Reed(1912),Girty(1907,1913)。解放后,我们进行了较多的工作,有较多的报道。
In the Early Permian bryozoans of South-west China(Hinganotrypa and Araxopora were studied by the authors in 1978 and 1979),33 species belonging to 14 genera are recognized(Text-fig.1),of which 6 species are new(Text-fig.2).The subdivisions of the Lower Permian in Southwest China are named the Liangshan,Chi-hsia and Maokou Formations ascendingly.The Liangshan Formation bears a few fragments of Fenestella and Septopora.Fistulipora subtubulo-sa Yang et Lu,Fistuliramus orbiculus Xia,Lu et Li,Fenestella hangchouensis Lu,Septopora robu-stiformis Yang et Lu and Hyalotoechus panxian-ensis sp.nov.Were discovered in western Gui-zhou.Fenestella hangchouensis commonly appe-ared in the Liangshan and Chihsia Formations in Guizhou,Sichuan,Guangxi,Jiangxi,Hunan and Anhui and were also found in the equivalent ho-rizon in Qinghai.Septopora robustiformis was found from the Chihsia Formation in Guizhou and Guangxi and from the Maokou Formation in Sichuan and Qinghai.Fistulipora subtubulosa first appeared in the lower Lower Permian in Qinghai.Therefore the bryozoans of the Liang-shan Formation are closely related to those of the Chihsia Formation.Fourteen bryozoan species appeared in the upper part of the Chihsia Formation.Fistulipora sinensis Yoh,F.waageniana Girty,Fenestella ha-ngchouensis Lu,Septopora robustiformis Yang et Lu can be found in the lower part of this for-mation.F.sinensis,as a typical form,is most ab-undant in the Chihsia Formation of Southwest,Central-south and Southeast China;it has been recorded in the equivalent horizons in Heilong-jiang,Liaonin and Nei Mongol of Northeast Chi-na,and in Kazakhstan and Armenia of the USSR.F.waageniana commonly associated with F.si-nensis occurred abundantly and extended to the Maokou Formation.In the bryozoans from the upper Chihsia Formation,Fistulipora willisiana Girty and Dybowskiella hupehensis Yang were only obtained in western Hubei and eastern Sichu-an.Dybowskiella guizhouensis sp.nov.appeared only in northern Guizhou,Fenestella subconstans Yang et Lu,Rhabdomeson mammillatum(Bretn-all)together with Polypora and Septopora richly occurred and extended to the Maokou Formation.The Maokou formation contains 26 species of bryozoans,which are:widespread in South-west China.10 species of Polypora,some Fistu-lipora and some above-described species ranged from the Chihsia to the Maokou Formations.Three new species,3 indeterminate species and other 10 species of Stenodiscus,Stenopora and some Fistulipora are limited merely in the Mao-kou Formation.Stenopora angulata Yang,Steno-discus giganteus Yang,S.delinghensis Yang et Lu and Fistulipora lunatifera Bassler were found in Southwest China,the first two of which appea-red abundantly in western Gansu-eastern Xinji-ang,the third is common in central Qinghai and the fourth was collected from Xizang and Ti-mor.Only a few specimens of Stenopora spicata Bassler,S.meekana(Girty),S.crassa Lonsdale and Fistulipora microparallela Yang et Lu can be found in Southwest China,they were first re-corded in the equivalent horizon in Timor,Si-chuan,Yunnan and Qinghai.From the geographic and stratigraphic vie-wpoint,the Early Permian bryozoans in South-west China are identical with those in Central-south China known generally as the Yangtze bryozoan-geographic province of the Tethys Re-alm.In this paper a brief discussion is made of the phylogenetic relationship to their correspon-ding species,such as Fistulipora,Stenopora,Fe-nestella and Polypora.Description of New Species Dybowskiella guizhouensis sp.nov.(Pl.I,fig.6;Pl.II,fig.2)Zoaria coarse and ramose.Apertures circu-lar to elliptical,distributed regularly;lunaria and peristomes distinct.Zooecial tubes elongated-cur-ved.Vesicles elongated in endozone and slender in exozone.In the external part,the new species is clo-sely similar to Dybowskiella sinensis Yang et Lu and D.hupehensis Yang,but it has smaller aper-tures and coarser zoaria,by which it is distingu-ished from the latter two forms.Tabulipora sinensis sp.nov.(Pl.II,fig.4;Pl.IIII,fig.4;text-fig.3)Zoaria ramose with distinct maculae.Aper-tures concave;larger apertures enclosed by a se-ries of smaller ones.Mesopores and acanthopo-res few;cavity absent in some mesopores,exila-pores and communicating pores present occasion-ally.Zooecial walls thickened but not beaded in exozone.Perforated and hemiphragm distinct but few.Tabulipora wangcangensis sp.nov.(Pl.II,fig.7;Pl.III,fig.5)Zoaria ramose.Apertures elliptical,oval or circular with corners,distributed irregularly.Lar-ge acanthopores and exilapores distinct with thic-kened and concentric walls;cavity sometimes absent in the latter,Perforated and hemiphragm distinct but few.Pseudobatostomella zunyiensis sp.nov.(Pl.III,fig.7;Pl.IV,fig.7)Zoaria hollow,thin and cylindrical,attached to the specimen of Araxopora petaliformis Yang et Lu,Apertures elliptical,sometimes lens-like.Larger and circular mesopores present at angles of zooecia,but elliptical,oval and smaller meso-pores richly appearing.Acanthopores small,alig-ned on every aperture.Diaphragms few.Zooeci-al walls thickened but not beaded in exozone.Hyalotoechus panxianensis sp.nov.(Pl.II,fig.9 Pl.IV,fig.2)Zoaria slender and ramose.Apertures con-cave,elongatedly elliptical or lens-like,regular-ly distributed in longitudinal and diagonal rows.Mesopores absent.Granulose or tubular but small acanthopores appearing occasionally.Zooecial walls thickened,fused and granulosed in exozo-ne.Short but thickened nodular superior hemise-ptum projected on the margin of exozone.Timanodictya zunyiensis sp.nov.(Pl.I,fig.3)Zoaria slender and bifoliate with elliptical but indistinct maculae gathered by larger apertu-res than average.Apertures concave,elliptical or oval,rarely rounded-triangular or crenulated.Mesopores subcircular or oval,only appearing at angles of zooecia.Acanthopores worm-like or cre-nulated in tangential section.Zooecial walls thic-kened and fused in exozone.Vesicles small and indistinct.Only one diaphragm or occasionally one perforated diaphragm occupying every zooe-cium.
作者
杨敬之
陆麟黄
Yang Jing-zhi;Lu Lin-huang(Nanjing Institute of Geology and Palaeontology,Academia Sinica)
出处
《古生物学报》
1984年第1期36-61,141-144,共30页
Acta Palaeontologica Sinica
