The barbs (Barbus spp.) of Lake Tana: a forgotten species flock?

Synopsis All living species occupy an ecological niche, and are positioned within a trophic hierarchy. Extinct organisms presumably held similar behavioral and coevolutionary characteristics in the past, and were susceptible to the same kinds of natural ecological pressures operating today. Paleoecological investigations are limited by the incompleteness of the fossil record, and particularly by a lack of behavioral data that are so fundamental to ecological studies of living communities and habitats. Opportunities to examine the coevolutionary structure of ancient communities from empirical data are extremely rare. One such opportunity is provided by the Lower Cretaceous Santana Formation of north-eastern Brazil, a series of richly fossiliferous strata approximately 110 million years old. Many fossil fishes from the Santana Formation contain identifiable prey, including decapod crustaceans and fishes. A trophic hierarchy of these organisms is reconstructed here, and their ecological relationships are discussed. Comparison is made with a similar fish fauna from the Upper Jurassic Solnhofen Limestone of Germany. Low-level, intermediate and high-level predators are identified in each fauna. Predator-prey relationships in the Santana fauna are strongly hierarchical, and are more focussed at the intermediate predator level than in Solnhofen. Comparison with a model of predator-prey relationships between fishes and benthic fauna of the Baltic Sea (which like the Araripe Basin represents a semi-enclosed environment) suggests that heavy predation on teleosts such asRhacolepis, occupying an intermediate trophic level, may have permitted benthic decapods to proliferate and exclude other benthic organisms. Less intense predation on fishes at the intermediate trophic level would allow their numbers to increase, thereby increasing the intensity of predation on the benthos at the base of the trophic hierarchy.     

First report of the giant snake Gigantophis (Madtsoiidae) from the Paleocene of Pakistan: Paleobiogeographic implications

We report here the discovery of madtsoiid snake remains from the early Paleocene Khadro Formation (Ranikot Group, Sindh, Southern Pakistan). These specimens consist of vertebrae and are referred to Gigantophis. This is the first report of Gigantophis from outside of Africa. The problem of the generic distinction between Gigantophis and Madtsoia is stressed. The specimens from Pakistan slightly differ from the single species (G. garstini) referred to the genus Gigantophis, but the available material does not allow further considerations and the fossil is referred to as Gigantophis sp. However, Gigantophis sp. from the Khadro Formation is more closely related to G. garstini, that is known only from the middle and late Eocene of northern Africa, than to any other species, thus suggesting dispersal between these two areas during the Paleocene or earlier. These results are consistent with the hypothesis of intermittent dispersals between the Indo-Pakistan Plate and Africa suggested by other fossil evidences.     

Foraminifera diversity changes and paleoenvironmental analysis: the Lower Cretaceous shallow-water carbonates of San Lorenzello, Campanian Apennines, southern Italy

A high-resolution stratigraphic study, carried out on the carbonate platform strata of the San Lorenzello section (Matese Mountains, southern Italy), Valanginian–Hauterivian in age, has allowed to: recognise lithofacies and their associations; assign the lithofacies associations to specific environments and individuate early meteoric diagenetic modifications, recurring at specific horizons. In this frame the vertical variation of benthic foram diversity has been analysed. On the whole, foraminiferal genera diversity decreases from open to restricted marine environments. Moreover, a climatic control on carbonate sedimentation is suggested by a Milankovitch cyclicity organised in elementary cycles, bundles and superbundles as well as by diagenetic characteristics testifying that humid and arid conditions alternated during the Early Cretaceous times. The orbital cyclicity is also documented by foraminiferal diversity changes, even if some discrepancies between the lithofacies and the diversity locally occur. Therefore, the above diversity changes do not appear to provide sufficient information for the sequence-stratigraphic interpretation of shallow-water carbonates.     

Upper cretaceous rudist and stromatoporid associations of Central Oman (Arabian Peninsula)

Summary Rudist and stromatoporid associations of the Campanian from Central Oman are nearly monospecific. They are dominated byDurania aff.nicholasi, Vaccinites vesiculosus, Torreites milanovici or phaceloid and massive stromatoporids. Several other rudist genera play a secondary role. The thickness of the associations is rarely more than one metre. Solitary corals do not occur in the associations. Colonial corals are less common, although they are up to 1 m high and show considerable diversity. There are no binders. The reef structure indicates variable hydrodynamic conditions. They are always associated with very shallow water. The pureDurania aff.nicholasi patches with large colonial corals andTorreites milanovici are presumably the most rigid structures. The near monospecific associations ofVaccinites vesiculosus are widely distributed. Although mostly preserved in situ, strong currents, presumably caused by tropical storms, have repeatedly impaired and interrupted growth. The specific growth characteristics of the shell of some rudists, especially the radiolitids, enable an estimation of the individual lifespan. Frameworks of approximately 1 metre thickness probably developed in ±100 years. The sediments of the complete sections are predominantly bioclastic.     

中国产蛇类模式标本的研究

模式标本产地在中国的蛇类有９５种,全国蛇类总数２０５种的４６．３％。模式标本产地最多的省是台湾（１５种）,命名模式标本最多的年代是１９２０￣１９２９年（１５种）,外国人中Ｂｏｕｌｅｎｇｅｒ命名１７种,中国人中赵尔宓命名１５种。     

Taxonomy, biostratigraphy and paleoecology of Cenomanian and Turonian ostracodes from the Western Interior Basin, Southwest Utah, USA

Cenomanian-Turonian ostracodes are reported from the western Colorado Plateau (Western Interior Basin) in the United States. Fifteen genera and twenty species are illustrated, six of which are new: Cytheromorphaperornata nov. sp., Looneyellaleckiei nov. sp., Asciocythereposterangulata nov. sp., Asciocytherearizonensis nov. sp., Cytheropteronclavifragilis nov. sp. and Hourcqiadakotaensis nov. sp. Three ostracode interval zones are proposed that broadly correspond to the existing late Cenomanian through to Middle Turonian Ammonite-zones of Kauffman et al. (1993). Paleoenvironments range from estuarine to coastal plain.     

Paleolimnology of Neusiedlersee,Austria

Neusiedlersee is a shallow, alkaline lake (Table 1), which came into existance by tectonic subsidence about 12000–14000 yr ago. At present, half of it is covered by Phragmites australis which developed after the lake fell dry for the last time in 1868.Due to its astatic character, with about 100–200 dry periods since the lake came into existence, most of the sediment of the open lake overlying a thick Tertiary layer presents a mixture of terrestrial and lacustrine components. Because of disturbance by wind, this lacks stratification. Preliminary investigations, however, demonstrated that within the fringing Phragmites belt — especially landward — such a stratification does still exist. In order to learn more about the history of the lake 18 deep freeze cores of between 135 and 190 cms in depth, were collected from the Phragmites belt and investigated for chemical data (see Gunatilaka, this volume) and the succession of ostracods. Most of the cores contain Tertiary material (foraminifera and ostracods) at their base, followed by a cold water fauna as indicated by the presence of Cytherissa lacustris. Indicators of high alkalinity (i.e. the remains of male Limnocythere inopinata and high salinity (Heterocypris salina) were found in only a few cores.     

Fine structure of the vomeronasal organ in the grass lizard, Takydromus tachydromoides

The squamates are composed of many taxa, among which there is morphological variation in the vomeronasal organ (VNO). To elucidate the evolution of chemoreception in squamate reptiles, morphological data from the VNO from a variety of squamate species is required. In this study, the morphology of the VNO of the grass lizard Takydromus tachydromoides was examined using light and electron microscopy. The VNO consists of a pair of dome-shaped structures, which communicate with the oral cavity. There are no associated glandular structures. Microvilli are present on the apical surfaces of receptor cells in its sensory epithelium, as well as on supporting cells, and there are centrioles and ciliary precursor bodies on the dendrites. In addition to ciliated cells and basal cells in the non-sensory epithelium, there is a novel type of non-ciliated cell in T. tachydromoides. They have constricted apical cytoplasm and microvilli instead of cilia, and are sparsely distributed in the epithelium. Based on these results, the variation in the morphology of the VNO in scincomorpha, a representative squamate taxon, is discussed.     

中国蛇类保护和养殖及展望

蛇类是中国一类重要的野生动物资源,对其利用由来已久,然而随着环境变化和社会发展,致使蛇类野生资源急剧下降,但从另一方面也促进了对蛇类人工驯养繁育的发展和探索。作者总结了中国蛇类资源概况、保护法律法规和措施以及上世纪80年代兴起的蛇类养殖及技术简况。     

Latitudinal variation in thermal ecology of North American ratsnakes and its implications for the effect of climate warming on snakes

Behavioral thermoregulation is expected to be critical in determining the capacity of reptiles to respond to climate warming and how that response will vary with latitude. We used radio-telemetry to compare behavioral thermoregulation among ratsnake (Elaphe obsoleta) populations in Texas, Illinois, and Ontario, a latitudinal distance of >1500 km. Despite numerous specific differences among populations, overall the thermal ecology was surprisingly similar during the months that snakes in all three populations were active. Preferred temperatures varied only slightly across the snakes’ range, the extent of thermoregulation was similar, and by varying when during the day and season they thermoregulated, snakes in all three populations realized body temperatures within their preferred temperature range 15–20% of the time. The ability to use fine-scale behavioral thermoregulation (i.e., selective use of habitats and microclimates) to a similar extent and achieve similar outcomes across such a wide latitudinal and climatic gradient is made possible by large-scale differences in timing of activity (ratsnakes in Texas switch to nocturnal activity during summer, whereas in Illinois and Ontario activity is exclusively diurnal and hibernation lasts 5–7 months). Modeling indicated that a 3 °C increase in ambient temperature will generally improve thermal conditions for all three populations. Our empirical analyses suggest that the snakes’ ability to respond to climate warming will be determined more by their capacity to adjust when they are active than by changes in the extent of fine-scale behavioral thermoregulation. The ability to adjust timing of activity appears to make many snakes fundamentally different from lizards. As such, the consequences of climate warming may be very different for these two groups of reptiles.     

Survey of the reptilian fauna of the Kingdom of Saudi Arabia. VI. The snake fauna of Turaif region

A collection of snakes in Turaif region, Kingdom of Saudi Arabia, an area that has been poorly documented for reptiles, consists of 28 specimens representing 11 species belonging to 4 families (Colubridae, Elapidae, Viperidae and Atractaspididae). This study presents the first comprehensive inventory of the herpetofauna of the Turaif province of Saudi Arabia. Co-ordinates: Latitude, longitude and altitude, of the collected specimens were mapped using GPS. Three of the snake species Lytorhynchus diadema, Pseudocerastes fieldi and Walterinnesia morgani reported by the authors in the present survey proved to be new records for Turaif region of Saudi Arabia.     

蛇场病死蛇与感染腐败谢瓦纳拉菌的探讨

目的探讨蛇场蛇死亡与细菌感染的关系。方法从８５条死蛇中随机抽样２０条,取其心脏积血进行微生物检验。结果从其中的１４条死蛇中分离出腐败谢瓦纳拉菌,分离阳性率为７０％。结论认为该菌可能是蛇病死的原因之一。     

Biogeography,ecology and history of Mediterranean Quercus ilex ecosystems

Quercus ilex sensu lato plays an important role in Western Mediterranean ecosystems, but is poorly developed in the Eastern Mediterranean where it is often replaced by Quercus calliprinos.The occurrence of Quercus ilex in the different bioclimates and their thermic subdivisions is presented on a small scale. Under certain geographical and ecological conditions, Quercus ilex participates in the organization of vegetation ecosystems from the meso-Mediterranean to the oro-Mediterranean altitudinal zones. Quercus ilex imposes microclimatic constraints on its associated species; it thus organizes and original understory vegetation structure (ethological groups) which will be defined in this study.One of the reasons for the success of Quercus ilex stems from its remarkable resistance to ecological constraints. A broad synthetic presentation of foliar area index variations in relation to different types of stress serve as a basis for an explanation of the sclerophyllous model in the Mediterranean region.Finally, historical factors are outlined as being critical characteristics in the determination of the present organization and spatial structure of Quercus ilex ecosystems. These considerations will be analyzed from a paleobioclimatical point of view, including data related to human pressure.     

蛇毒清合剂治疗海蛇咬伤临床观察

目的观察蛇毒清合剂对海蛇咬伤的疗效。方法将44例海蛇咬伤患者分为治疗组22例,对照组22例,两组患者均给予常规治疗,治疗组加服蛇毒清合剂,并比较两组患者咬伤48h后的血清酶学三项（CK、LDH、AST）,比较两组患者治疗7天后的疗效、治疗结束时疗程及呼吸衰竭发生率、急性肾损伤发生率。结果两组患者临床疗效比较,治疗组优于对照组（P〈0．05）,酶学三项和疗程的差异均有统计学意义（P〈O．05）}其呼吸衰竭发生率、急性肾损伤发生率虽有差异,但无统计学意义（P〉0．05）。结论蛇毒清合剂对海蛇咬伤有显著疗效。