甘肃酒泉盆地下白垩统Pseudofrenelopsis(掌鳞杉科)的发现及其意义

记述甘肃酒泉盆地早白垩世地层中发现的两种掌鳞杉科植物化石Pseudofrenelopsis dalatzensis(ChowetTsao,1977)Cao ex Zhou和P.gansuensissp.nov.。其中,归入P.dalatzensis的标本无论是小枝形态还是表皮构造都与产于吉林延吉盆地大砬子组的模式标本一致。定为新种的标本小枝较粗,可能只有一枚叶;节间角质层厚25—30μm,表面没有乳突和表皮毛,气孔器和表皮细胞均规则成行排列;气孔器圆形或椭圆形,较大,整体下陷。副卫细胞通常5—7个,少数可达8—9个。保卫细胞仅部分保存。已发现的Pseudofrenelopsis均分布于北半球,时代限于早白垩世,且多为早白垩世晚期,其中P.dalatzensis在模式标本产地与丰富的被子植物共生,应为早白垩世Aptian到Albian期。该种在酒泉盆地中沟组的出现说明该组的时代最高可到Aptian或Albian期。已有资料还表明,Pseudofrenelopsis主要生活于有季节变化、盐度较高或较干旱的环境中,这与酒泉盆地早白垩世沉积物和其他门类的化石所指示的环境特征相符合。     

新疆准噶尔盆地早侏罗世掌鳞杉科植物化石 及古大气CO2浓度

植物化石气孔参数分析是目前恢复古大气二氧化碳浓度较为精准的方法之一,银杏类和松柏类等是恢复古大气CO_2浓度常用的化石类群。本文利用新疆准噶尔盆地下侏罗统三工河组的松柏类掌鳞杉科Brachyphyllum(Hirmeriella?)sp.化石对早侏罗世大气CO_2浓度进行了重建,获得早侏罗世大气CO_2浓度为～1200ppm,丰富了早侏罗世大气CO_2浓度信息,进一步说明掌鳞杉科植物通过气孔比率法在重建侏罗纪大气CO_2浓度方面的可靠性。掌鳞杉科植物的旱生构造和较高的大气CO_2浓度表明早侏罗世Toarcian期大洋缺氧事件在陆地生态系统内可能产生了一定的响应。     

中国东北早白垩世一种新的昼蜓化石 (蜻蜓目: 昼蜓科)

本文记述昼蜓科化石一新属新种-孟氏丽昼蜓Abrohemeroscopus mengi gen.et sp.nov.。化石采自辽宁省义县早白垩世九佛堂组地层中。新属与巴依萨昼蜓Hemeroscopus Pritykina,1977在形态上比较相似,但在演化程度上更为原始,主要体现在下面几个方面：(1) 后翅臀套较小,仅有6～7个翅室; (2) 径增脉（Rspl）缺; (3) 后翅CuAa脉弯曲,带有5个明显的后分支; (4)前翅MP脉不显短,终止于翅后缘近翅结处; (5) 翅痣下有一个明显的支脉; (6) 后翅CuAa 和MP域基部较窄,在三角室下方仅有1排翅室。这是昼蜓科化石在中国的最老记录。     

八种散白蚁和一种异白蚁翅面微刻点的扫描电镜观察──(等翅目:鼻白蚁科)

用扫描电镜观察八种散白蚁和一种异白蚁有翅成虫翅面微刻点．结果表明,除了观察到文献中已报道的微刻点类型（舌状乳突、尖头状乳突和粉刺状突起）外,还发现有小刺突和毛．而且同一种白蚁翅背、腹面的微刻点类型存在明显的差异．根据微刻点类型就细颚异白蚁的分类地位作了初步探讨．     

辽宁黑山恐龙蛋──长形蛋类新分子的发现及其意义

辽宁西部黑山县下白垩统发现我国最早的恐龙蛋壳化石,属长形蛋类,取名常氏黑山蛋（新属新种）（Ｈｅｉｓｈａｎｏｏｌｉｔｈｕｓ ｃｈａｏｇｉｉ　ｏｏｇｅｎ ｅｔ ｏｏｓｐ ｎｏｖ）。该新属种蛋壳表面具密集的细瘤状纹饰,局部相邻的两个或数个细瘤联结成链条状细脊,锥体层极薄,锥体层与柱状层之比约为１：７。根据埋藏情况来看,产蛋恐龙生活在湿热、植被茂盛的河湖沼泽附近的生态环境。     

A LONG-BODIED LIZARD FROM THE LOWER CRETACEOUS OF JAPAN

Abstract:  Platynotan lizards underwent a dramatic Late Cretaceous radiation into marine habitats. Beginning with small-bodied forms, the lineage culminated with the mosasaurs, large predatory lizards with a world-wide distribution in the Santonian–Campanian. Moreover, the marine squamate radiations of the Cenomanian–Turonian are remarkable in having produced a range of long-bodied, reduced-limbed swimmers (dolichosaurs, adriosaurs, coniasaurs and limbed snakes) that seem to have thrived in the shallow coastal environments of the Western Tethys region. Until now, none of these long-bodied aquatic squamates has been recorded prior to the Cenomanian, none has been recovered from a non-marine locality and none is known from Asia. Here we describe a small, gracile, long-bodied mosasauroid lizard from a swampy continental deposit in the Lower Cretaceous of Japan.     

内蒙古查布地区下白垩统巨齿龙足印化石

内蒙古鄂尔多斯市鄂托克旗查布地区下白垩统中产有大量的蜥脚类和兽脚类恐龙足迹及鸟类足迹化石,作者对这个地区的足迹化石进行全面普查,发现许多新暴露出来的恐龙足迹化石,包括兽脚类恐龙足迹一新属新种Chapuslockleyiichnogen.etichnosp.nov.属于巨齿龙类(megalosaurid)所留。与兽脚类足迹保存在一起的蜥脚类足迹Brontopodusbirdi分布凌乱,反映了造迹恐龙搏斗的场面。通过测量连续的兽脚类足迹计算,Chapuslockleyi的造迹恐龙的行走速度为4.33km/h。通过足迹化石还识别出造迹恐龙的病态特征。     

MARINE REPTILES FROM THE LOWER CRETACEOUS OF SOUTH AUSTRALIA: ELEMENTS OF A HIGH-LATITUDE COLD-WATER ASSEMBLAGE

Abstract: The Lower Cretaceous rocks of South Australia have yielded a diverse marine reptile assemblage of up to five families of plesiosaur (including a new cryptoclidid or cimoliasaurid, indeterminate elasmosaurids, a possible polycotylid, rhomaleosaurids, and pliosaurid) and one family of ichthyosaur (ophthalmosaurid). Other common associated vertebrates include chimaerids and osteichthyans. Sharks, dipnoans and dinosaurs are uncommon and marine turtles are notably absent. The main fossil‐producing strata belong to the Lower Aptian–Lower Albian Bulldog Shale although the Upper Albian Oodnadatta Formation has produced isolated elements. Both these units comprise finely laminated shaly mudstones and claystones deposited in a transgressive shallow coastal, epicontinental marine environment. Estimates of palaeolatitude place South Australia between 60° and 70°S, in the late Early Cretaceous. Sedimentary structures (including lonestone boulders and glendonites), fossils, isotope data and climatic modelling also indicate that seasonally cool–cold conditions (possibly with winter freezing) prevailed during deposition of the Bulldog Shale. This contrasts markedly with climate regimes typically tolerated by modern aquatic reptiles but suggests that some of the South Australian Mesozoic taxa may have possessed adaptations (including elevated metabolic levels and/or annual migration) to cope with low temperatures. A high proportion of juvenile plesiosaur remains in the Bulldog Shale might also indicate that nutrient‐rich cold‐water coastal habitats functioned as both ‘safe calving grounds’ and refuges for young animals prior to their entering the open sea as adults. The occurrence of plesiosaurs and ichthyosaurs in the high‐latitude Lower Cretaceous of southern Australia, along with plesiosaurs and mosasaurs in the Upper Cretaceous of South America, Antarctica, New Zealand and the Chatham Islands, demonstrates that Mesozoic marine reptiles utilized southern high‐latitude environments over a considerable period of time, and that these records do not represent casual occupation by isolated taxa.     

青海省下三叠统巴颜喀拉山群下亚群的孢粉组合

首次对青海中部下三叠统巴颜喀拉山群下亚群孢粉组合进行综合研究。共发现孢粉:下岩组59属89种(包括1新种),按在组合中百分含量的平均值,蕨类植物孢子占55.71%,裸子植物花粉占36.3%,疑源类9属2种占7.36%,称之为Lundbladispora-Cycadopites-Veryhachium组合;上岩组86属119种(包括3新种),蕨类植物孢子占46.03%,裸子植物花粉占31.91%,疑源类13属16种占21.64%,称之为Limatulasporites?Cycadop-tes?Tubermonocolpites-Micrhystridium组合。上述孢粉组合特征,大体可与国内外早三叠世孢粉组合对比,因此,巴颜喀拉山群下亚群的时代应属早三叠世。     

辽西下白垩统九佛堂组长腹细蜂(昆虫纲,膜翅目)化石一新种

描述的昆虫化石产自辽西朝阳县大平房乡原家洼九佛堂组。该化石为一新种,命名为原家洼始长腹细蜂(Eopelecinusyuanjiawaensissp.nov.),归入长腹细蜂科(Pelecinidae)。该科是昆虫纲膜翅目中一个现生小科,仅包括1属3种,分布在美洲大陆。该科在白垩纪曾广泛分布于欧亚大陆,在我国曾发现于辽西的义县组和山东的莱阳组中。     

灭幼脲引致蚊虫畸形的扫描电镜观察

目前对有害昆虫以灭幼脲Ⅰ号的效果最好,它是一种昆虫生长调节剂。它与一般的化学杀虫剂不同,根据目前国外资料的报道,其杀虫作用主要是抑制昆虫表皮几丁质的合成,使昆虫的生长发育和变态受到阻滞而死亡。本文报道灭幼脲Ⅰ号对致倦库蚊和骚扰阿蚊引起形态变化的扫描电镜及组织学观察结果。     

英国约克郡海相下白垩统完整保存的假拟节柏枝条(英文)

首次描述英格兰北部东约克郡海相下白垩统斯匹敦泥岩组欧特里夫阶岩段所产出已灭绝的掌鳞杉科松柏稀枝假拟节柏保存特别完好的营养枝。由于很高程度的黄铁矿化,这些枝条几乎没有受到挤压而是呈三维立体形状,并且其内部解剖构造很大程度上得到保存,尤其是木质组织。这些枝条为原来的角质层所包裹,因而其表皮构造的解剖细节,包括气孔器的特征也完好保存着。本文是对斯匹敦泥岩组中可资鉴定植物化石的首次详尽的报道。此研究拓展和补充了先前局限于对英格兰南方和其它地区主要为陆相岩层中产出的稀枝假拟节柏研究。