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1.
A. GUY PLINT RON K. PICKERILL 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1985,18(4):341-347
Middle Eocene, non-marine sediments from southern England contain examples of Teredolites borings in two contrasting palaeoenvironmental settings, viz.: (A) as in situ borings in an allochthonous lignite in an abandoned river channel and (B) as bored logs in cross-bedded fluvial sandstones of probable point-bar origin. The lignite is 0.30 m thick, of which the upper 0.20 m is intensely bored. Rounded pebbles of ?charcoal at its base also show small borings. A log in a fluvial sandstone shows densely-packed. radial club-shaped borings. now filled with sandstone. The wood substrate has subsequently been oxidized away. To our knowledge, this is the first detailed account of Teredolites from an ancient freshwater setting. 相似文献
2.
Didier Merle 《Geobios》2005,38(4):505
Jsowerbya, nov. gen. (Gastropoda: Muricidae) includes three species from the Eocene of the Paris and Hampshire basins. It increases the number of extinct muricid genera, which curiously represent a very small fraction of the described genera. The species of Jsowerbya, often mistaken for the muricopsine genus Muricopsis, possess a unique combination of characters shared with the subfamilies Ocenebrinae and Ergalataxinae. A cladistic analysis, based on structural homologies of the spiral sculpture, however, suggests that Jsowerbya is closely related to the Ocenebrinae. Thus, Jsowerbya is here regarded as one the most basal Ocenebrinae. 相似文献
3.
本文记述了在云南省建水县岔科地区发现的哺乳动物化石。根据豫鼠(Yuomys),定地层时代为晚始新世。这套地层暂称岔科组,以示滇南地区第一个含早第三纪哺乳动物的地点和层位。 相似文献
4.
A recently discovered partial skeleton of the adapid Cantius trigonodus from the early Eocene Willwood Formation of the Bighorn Basin, Wyoming, documents substantial new information about the anatomy of the oldest lemuriform primates. It is very similar in all features to its descendant, middle Eocene Notharctus, and both exhibit numerous resemblances to certain extant Malagasy lemurs, particularly Lepilemur, Propithecus, Lemur, and Hapalemur griseus. Like these forms, Cantius had relatively long hind limbs and short forelimbs. Forelimb traits (prominent brachialis flange of the humerus, well-developed olecranon process of the ulna, and strong shafts of the ulna and radius) suggest active use of the forelimbs in progression. Specializations in the hind limb (e.g., expanded articular surface of the femoral head, narrow and elevated patellar trochlea and prominent lateral trochlear ridge, posteriorly oriented femoral and tibial condyles, narrow and elongate talus, and hallucal metatarsal with prominent peroneal tubercle) indicate capabilities for leaping and for powerful grasping with an opposable hallux. Cantius was presumably primitive in having a relatively long ischium and much more distal inferior tibial tuberosity than most extant lemurs--traits suggesting that powerful extension of the thigh and flexion at the knee were important in its locomotion and posture. We interpret Cantius as an active arboreal quadruped with a propensity for leaping. The existence of this skeletal structure in one of the oldest primates of modern aspect suggests that it represents the primitive lemuriform morphology. 相似文献
5.
Shi Ronglin 《古脊椎动物学报》1989,(2)
<正> This paper describes Mammalian fossils of 18 species discovered at Donghuangzhuang,about 15 km from NE of Qufu county,Shandong Province.The materials were collected bya farmer in 1984 and were sent to The Shandong Provincial Museum for studing.A short fieldinvestigation was made by Wang Jinwen,Sha Yesue(BGMRSD),Han Qingwen(SDM)andthe present author in same year.The age of the fauna is tentatively considered as the late Late Eocene,probably correlatedas the Heti Fauna(Yuanqu Basin).It represents the first occurrence of Late Eocene fossils inthis province. 相似文献
6.
新疆准噶尔盆地三个泉地区几种始新世哺乳类 总被引:8,自引:5,他引:3
本文记述了准噶尔盆地北缘三个泉地区依希白拉组中采到的踝节类、蹠行类、全齿类和恐角类化石。根据这些化石,依希白拉组的时代可能和北美中始新世勃力吉期相当。文内,通过文献分析,认为周明镇和胡长康(1956)记述的真恐角兽的前臼齿可能产自三个泉附近的依希白拉组。 相似文献
7.
8.
《Palaeoworld》2023,32(1):148-155
The extant taeniopterygid genus Brachyptera Newport, 1848 is reported from the Eocene Baltic amber for the first time. A new species, Brachyptera dewalti n. sp. (Plecoptera: Taeniopterygidae), is described and illustrated based on a well-preserved female in the amber, distinguished by the presence of three well-developed ocelli, the dark color of antennae, maxillary palps, head, prothorax, and abdominal segments, the CuA vein of forewing with three branches, the nearly rhombus, dark brown postgenital plate, and the four-segmented cerci. It is the fourth taeniopterygid species known from the Baltic amber. 相似文献
9.
APaleogenemammalianfauna,herenamedtheShanghuangfauna,wasdiscoverednearthevillageofShanghuang,closetoLiyangCity,JiangsuProvince,China(Fig.1).Atpresent,rouglilysixtyspeciesoffossilmammalshavebeenrecogniedintheShanghuangfauna.Manyofthesemammaltaxaarenewtoscience,andothersrepresentnewoccurrencesfortheEoceneofChina.ParticularlywellrepresentedintheShanghuangfaunaaremicromammals(includingmarsupials,insectivores,rodents,lagomorphs,primates,andbats)thathaveseldomifeverbeenfoundinotherEoceneAsianl… 相似文献
10.