我国冀北西瓜园组丰宁叶肢介模式种形态学再研究（英文）北大核心CSCD

通过扫描电镜重新研究产自冀北丰宁满族自治县花吉营下白垩统西瓜园组的花吉营丰宁叶肢介(Fengninggrapta huajiyingensis)的正型标本。电镜照相揭示以前光学照相无法分辨的重要分类特征,其中包括:1)胎壳附近窄生长带上的小到中网装饰和密而细的线脊夹小网装饰;2)胎壳附近生长线上的小网装饰;3)靠腹边缘生长带粗壮线脊下端向下接近生长线时膨胀变成三角形"滨生长线瘤"。从而修定丰宁叶肢介的特征描述。     

我国冀北西瓜园组丰宁叶肢介模式种形态学再研究（英文）

通过扫描电镜重新研究产自冀北丰宁满族自治县花吉营下白垩统西瓜园组的花吉营丰宁叶肢介(Fengninggrapta huajiyingensis)的正型标本。电镜照相揭示以前光学照相无法分辨的重要分类特征,其中包括:1)胎壳附近窄生长带上的小到中网装饰和密而细的线脊夹小网装饰;2)胎壳附近生长线上的小网装饰;3)靠腹边缘生长带粗壮线脊下端向下接近生长线时膨胀变成三角形"滨生长线瘤"。从而修定丰宁叶肢介的特征描述。     

宽网叶肢介属重要分类特征的发现

通过扫描电镜重新研究了产自俄罗斯维特奴河流域下三叠统维特奴宽网叶肢介(Loxomegaglypta wetlugiana Novo-jilov, 1958)的正模标本。扫描电镜成像揭示了光学照相无法分辨的重要分类学新特征, 其中包括: 生长带饰有圆形、角状或椭圆形小筛坑状装饰(直径15–25 μm), 筛坑被不同形状的隆起包围。均匀分布的针孔(直径4–6 μm)不但出现在筛坑里, 而且布满了筛坑周围的隆起。这种装饰与该属建立时描述的多角状大网格装饰区别较大。在此基础上,本研究修订了宽网叶肢介属生长带的装饰特征。     

Difalsisca ——叠饰伪转叶肢介新属

叠饰伪转叶肢介(Difalsisca)的特征是初生壳大,背缘末端的后背角反弯曲,装饰为小针网状,在壳的后腹部生长带上有叠网状装饰。新属与伪转叶肢介属(Falsisca)的区别就是具有叠网状装饰,其他特征均相似。叠饰叶肢介科(Diestheriidae Zhang et Chen)是1976年建立的。主要特征是在壳表面原有的网、线和线网状装饰之上又叠覆一层更大的网状物,称为“叠网状装饰”,它主要分布在壳的后腹部生长带上。本科包括叠饰叶肢介属(Di-estheria Chen,1976),新叠饰叶肢介属(Neod-     

靖远真叶肢介(Euestheria jingyuanensis)壳瓣的装饰特征及其生物地层学意义

Euestheria jingyuanensis(靖远真叶肢介)命名于甘肃靖远中侏罗统王家山组油页岩段,是广泛分布于我国中侏罗世E.ziliujingensis(自流井真叶肢介)群的重要分子之一,其壳瓣具有典型的小网状装饰。通过对E.jingyuanensis模式标本进行扫描电镜观察发现:其生长带上具有不规则的网状和线状装饰,与同属E.luanpingensis(滦平真叶肢介),E.ziliujingensis等具有细小网状壳饰的种易于区分。E.jingyuanensis常与E.ziliujingensis等种共生,以前认为内蒙古宁城道虎沟层含有E.jingyuanensis,但目前看道虎沟层可能只含有E.luanpingensis。E.jingyuanensis壳瓣装饰超微结构的确定对Euestheria属的分类以及中侏罗统地层对比研究工作具有一定意义。     

安徽繁昌癞痢山东裂隙堆积新发现的早更新世鼠科化石*

1962 年, M. J. Copeland 报道了加拿大北极梅尔维尔岛中–上泥盆统梅尔维尔岛组的叶肢介化石。2014 年秋, 作者对馆藏在加拿大地质调查所的模式标本进行了观察、照相, 发现了一些新的重要的分类特征, 在此予以补充修订。1、壳瓣具有 3–5 条放射脊的翼李氏叶肢介属(Pteroleaia)是梅尔维尔岛泥盆纪最具特色的类型, 与其保存在同一层面上还发现有另一类个体十分微小的棒叶肢介属(Rhabdostichus), 该属与美国中北部及加拿大艾伯塔地区同时代的叶肢介可以对比, 之前这一类型的标本仅见于该地区中–晚泥盆世地层, 其在北极地区的出现为首次报道。同时对归于棒叶肢介科(Rhabdostichidae)的另外两属(Rhabdostichops 和 Archaeositum)的含义进行了甄别, 认为前者建属特征不成立, 后者不应属于该科。2、产于梅尔维尔岛 Dundas 半岛的叶肢介, 个体数量多且密集堆积, 曾被鉴定为 Asmussia canadensis 的那些个体的壳顶都发育有一个细小的、凸起的卵形瘤状构造, 依据这一重要鉴定特征, 其分类位置应属于锥顶叶肢介亚科(Vertexiinae)的犄叶肢介属(Cornia), 从而使这一属的地质历程从石炭纪追溯到中泥盆世。这些化石的修订, 丰富了我们对加拿大北极地区泥盆纪叶肢介面貌的认识, 为研究相关类群的起源、演化提供了新的信息。文中也讨论了李氏叶肢介亚目(Leaiina)三个早期叶肢介类群之间的相互关系, 认为 Pteroleaia (Rostroleaiidae)代表了形态特殊的一个演化分枝, 早仅见于泥盆纪并很快灭绝。壳瓣具有两条放射脊的叶肢介科(如: Leaiidae)被认为是李氏叶肢介亚目的演化主干, 兴盛于石炭纪和二叠纪。广东中泥盆世早期(Givetian)桂头群中的叶肢介组合以 Hepuleaia (Praeleaiidae)为主, 并包含壳瓣具两条放射脊的种类, 该组合是迄今已知李氏叶肢介亚目的最早代表, 这表明该亚目应起源于中国而非欧洲。     

江西上三叠统安源组叶肢介一新属*

香溪叶肢介亚科(Xiangxiellinae)以壳瓣胎壳较大、壳上具有一条或两条短脊为特征,包括两个属:原单脊叶肢介属(ProtomonocarinaTasch,1962)和香溪叶肢介属(XiangxiellaShen,1976)。该亚科化石广布于世界各地,最早出现于我国晚石炭世,三叠纪末消失。本文建立的新属叉脊叶肢介(Dicerestheriagen.nov.),以胎壳上具有两条呈“人”字形向前后分叉的、粗壮的短脊为特征,与香溪叶肢介的构造特征最为接近。推测新属壳瓣胎壳脊的形成与闭壳肌附着引起的壳瓣变异或与生态环境变化有关。化石产于江西抚州崇礼县礼陂煤矿,上三叠统安源组徐坊段。湘赣一带安源组为一套含煤地层,属于滨海、近海、沼泽沉积区,产半咸水类型的双壳类,时代认为卡尼及早诺利期。植物化石Ptiozamites–Anthrophyopsis组合是诺利期的代表,适宜于热带、亚热带气候,滨海环境生长的群落。因此推测新属是一个生活在炎热、潮湿的热带-亚热带气候近海沼泽环境的类型。     

黑龙江省嘉荫地区晚白垩世太平林场组的俞氏链叶肢介

黑龙江省嘉荫县东南永安村东的黑龙江南岸上白垩统嫩江阶太平林场组底部的黑灰色页岩中,产丰富的俞氏链叶肢介(Halysestheria yui)化石。通过对这批化石材料的扫描电镜研究,发现该种化石壳表在靠背部的生长带上的长线脊间布满小网格装饰。而在光学显微镜下,这种装饰显示为长线脊间偶夹分布于生长带下半部的短线脊,修正了该种化石的特征描述。同时通过该种与青冈链叶肢介(Halysestheria qinggangensis Chen)的对比研究,发现两者区别不大,由于前者命名在先,后者应该是前者的同物异名。     

论非洲叶肢介科的分类

叶肢介化石生长线下缘锯齿状构造曾作为非洲叶肢介科(Afrograptidae)分类的主要特征,通过扫描图像,从比较解剖学研究入手,揭示了现生与化石叶肢介壳瓣的锯齿构造是由于分布于生长线的一排刚毛,基部关节脱落而形成的;分析了生长线刚毛的形态是属于长针形的轴刚毛,主要司触角功能;在5科18属现生叶肢介中,至少3科7属32种具有生长线刚毛,22属化石叶肢介有锯齿构造;作者认为这一构造被视为非洲叶肢介科分类的主要依据是不合适的,壳瓣的放射褶或粗瘤构造在高级分类上更重要,进而对该科的含义进行了厘定;从壳瓣具有多条放射褶这一构造特征来看,它与小叶肢介超科(Estheriellioidea)的成员在发生关系上比较密切,小叶肢介超科可提升为亚目(Estheriellidea),包括小叶肢介超科和非洲叶肢介超科,是中生代初兴起的一个类群。在白垩纪中期消失。     

英国早石炭世大网叶肢介科一新属

描述了采自英国伯维克郡下石炭统下泥石群（杜内附）叶肢介一新属－ｌｏｎｇｅｓｈｅｒｉａｇｅｎ．ｎｏｖ．据壳瓣生产带上发育大网状纹饰构造。归属于Ｌｏｘｏｍｅｇａｇｌｙｐｔｉｄａｅ科,从而使该科的地质历程从晚二叠世,一直追溯到早石炭世早期。讨论了新属与该科其它属之间的形态特征联系。认为化石为原理藏,含叶肢介崦层属非海相沉积。     

Significance of head and carapace pores inCeriodaphnia (Crustacea,Cladocera)

Twelve species ofCeriodaphnia were examined by light and scanning electron microscopy for the presence of head and carapace pores. Rostral pores, similar to those in the Scapholeberinae (Dumont & Pensaert, 1983) were found in all species, situated just anterior to or between insertions of the antennules. With two exceptions, the pattern of reticulations around the pores was distinctive for each species. Oval ‘head pores’ or fenestrae occur consistently on the anterior surface of the cervical notch of juvenile and adultC. dubia, cf.dubia (from Australia),lacustris, andreticulata. The patterns of reticulations around a fenestra are unique to each species. It appears thatC. cornuta (s.l.) in the Americas has a fenestra, whereas AustralianC. cornuta (s.s.) has none. Minute pores often occur bilaterally anterior and posterior to the cervical notch in heavily reticulated individuals of several species but are not constant enough to be taxonomically useful. Well-defined small pores are situated within narrow reticulations just medial to the ventral and posterior valve margins ofC. dubia, lacustris, andreticulata. These open into carapace glands of unknown, perhaps secretory, nature. Similar glands have been observed in related taxa. Such glands and marginal pores occur only occasionally or not at all in otherCeriodaphnia. Other small pores sometimes occur among reticulations of the head, fornix, and lateral and antero-ventral surfaces of the valves. They are found more often in juvenile or heavily reticulated individuals. As yet no consistent pattern to their occurrence among species has emerged. Head and carapace pores inCeriodaphnia may be most useful in identifying species rather than in determining species groups or evolutionary patterns within the genus.     

Evidence for a dioecious mating system in Early Jurassic Hardapestheria maxwelli gen. et sp. nov. (Crustacea,Branchiopoda, Spinicaudata) from the Kalkrand Formation of Namibia

A new spinicaudatan (clam shrimp), Hardapestheria maxwelli gen. et sp. nov., is described from the Jurassic Kalkrand Formation of central Namibia. Specimens were collected from a sedimentary interbed within a succession of flood basalts. These are the first spinicaudatans to be described from the Jurassic of south‐western Africa. The new taxon is assigned to the family Eosestheriidae based on the combination of punctae and radial ornamentation on the carapace. Ornamentation on the growth bands in H. maxwelli differs from other eosestheriid genera because the punctate ornamentation is not restricted to the dorsal region of the carapace. Instead, all growth bands include a proximal region with punctae even though the distal portion of each growth band may exhibit anastomosing lirae. Among well‐documented Mesozoic spinicaudatan genera, Hardapestheria is most closely related to Carapacestheria from the contemporaneous Kirkpatrick Basalt of Antarctica and Yanjiestheria from the Early Cretaceous of China. Hardapestheria maxwelli displays sexual dimorphism, which can be definitively related to a dioecious mating system with discrete male and female individuals. Review of additional early members of the Eosestheriidae suggests that the maintenance of two discrete sexes was the ancestral state for the clade. The ability to discriminate sexual mating system type unambiguously is rare in fossils, and this new species sheds light on the relationship between environmental stability and mating system evolution.     

A NEW SPINICAUDATAN GENUS (CRUSTACEA: ‘CONCHOSTRACA’) FROM THE LATE CRETACEOUS OF MADAGASCAR

Abstract: A new spinicaudatan genus and species, Ethmosestheria mahajangaensis gen. et sp. nov., is described from the Anembalemba Member (Upper Cretaceous, Maastrichtian) of the Maevarano Formation, Mahajanga Basin, Madagascar. This is the first spinicaudatan reported from the post‐Triassic Mesozoic of Madagascar. The new species is assigned to the family Antronestheriidae based on the cavernous or sievelike ornamentation on the carapace. Of well‐documented Mesozoic spinicaudatan genera, Ethmosestheria mahajangaensis is most closely related to Antronestheria Chen and Hudson from the Great Estuarine Group (Jurassic) of Scotland. However, relatively poor documentation of the ornamentation of most Gondwanan Mesozoic spinicaudatan species precludes detailed comparison among taxa. Ethmosestheria mahajangaensis exhibits ontogenetic trends in carapace growth: a change in carapace outline from subcircular/subelliptical to elliptical, and from very wide juvenile growth bands to narrow adult growth bands. Ornamentation style, however, does not vary with ontogeny. Ethmosestheria mahajangaensis individuals lived in temporary pools in a broad channel‐belt system within a semiarid environment; preserved desiccation structures on carapaces indicate seasonal drying out of pools within the river system. Specimens of Ethmosestheria mahajangaensis are preserved with exquisite detail in debris flow deposits; these are the first spinicaudatans reported from debris flow deposits. These deposits also contain a varied vertebrate fauna, including dinosaurs, crocodyliforms, turtles, and frogs. Rapid entombment of the spinicaudatan carapaces likely promoted early fossil diagenesis leading to highly detailed preservation.     

Micromorphology of fruits and seeds of Iranian Geranium (Geraniaceae), and its systematic significance

The fruit and seed micromorphology of 22 species of Geranium, representing the eight sections of the genus represented in Iran (G. sectt. Dissecta, Geranium, and Tuberosa of subgen. Geranium; sectt. Batrachioidea, Divaricata, Lucida, Ruberta and Trilopha of subgen. Robertium), have been examined by scanning electron microscopy (SEM). Macro‐ and micromorphological characters, including fruit and seed shape, size, color, hair type and density, mericarp ornamentations, hilum position, seed coat pattern, epidermal cell shape, and anticlinal and periclinal cell walls, are presented. Two microsculpturing patterns are recognized on the mericarp surface: reticulate and pusticulate. The micromorphology of the seed coat showed four distinctive cell patterns. The seed epidermis is constructed either of polygonal, elongated polygonal, or square to rectangular cells. The polygonal type is the most common among the studied species, but the variation in testa cell characters, their size and shape, may provide further information and useful diagnostic characters at specific and infraspecific rank. The shape and color of the seeds are, however, of little systematic value. Fruit characters were found to be important for separating taxa at infrageneric rank and our results show that the species can be separated into subgenera and sections based on fruit morphology.     

A first record of anchialine crab of the genus Orcovita Ng and Tomascik, 1994 (Decapoda: Brachyura: Varunidae) from Japan, with description of the species

Orcovita miruku, new species, is described from Ishigaki Island, southern Ryukyu Islands, Japan. Orcovita miruku is easily distinguished from the other congeners by the presence of three teeth (including external orbital angle) on the anterolateral margin of the carapace. Orcovita angulata may be allied to O. miruku, but there are a number of differences in the characters of the carapace and the ambulatory legs. The holotype, obtained from an anchiline pool in a limestone excavation, is the only specimen collected thus far, and this is the first record of an anchiline crab from Japan.     

Microornamentation of Lioestheria, Mimoleaia, and Echinolimnadia (conchostraca) from the terminal Permian of Siberia

Previously unknown minute ornamentation patterns of conchostracans are described based on SEM investigation of several collections from the terminal Permian volcanic deposits of the Tunguska Syneclise. Lioestheria (Lioestheriidae) shows ovally elongated cells arranged in rows along the growth bands, Mimoleaia (Leaiidae) has large polygonal cells with double walls, and Echinolimnaia (Echinolimnadiidae fam. nov.) displays a pattern with small polygonal cells bearing small spines along their walls. Diagnoses of genera and species are refined. New data about their distribution are presented.     

Relative growth and onset of morphological sexual maturity of the freshwater crab Sylviocarcinus pictus in a river of the Caatinga of northeastern Brazil

The aim of this study was to investigate the relative growth and onset of morphological sexual maturity of the freshwater crab Sylviocarcinus pictus. Specimens were collected every month from October 2013 to September 2014, at night, on a stretch of the river Guaribas, Piauí, Brazil. Crabs were sexed and their carapace width (CW, independent variable), carapace length (CL), cheliped propodus length (PL) and height (PH), gonopod length (GL), and abdomen width (AW) (dependent variables) were measured. These measurements were related to characterise relative growth and possible sex differences. On average males were larger than females (p = 0.0001). Size at the onset of morphological sexual maturity was defined by relating CL vs. PL for males (30.82 mm) and CL vs. AW for females (28.63 mm). These are considered secondary sexual characters and reflect initial size at morphological sexual maturity with greater precision. The differential cheliped growth of males may be related to courting and disputes with other males, while the allometric growth of the abdomen of females indicates increased probability of reproductive success.