A NEW GENERALIZED PAUCITUBERCULATAN MARSUPIAL FROM THE OLIGOCENE OF BOLIVIA AND THE ORIGIN OF 'SHREW-LIKE' OPOSSUMS

Abstract:  Insights into the origin of 'shrew-like' oposssums of South America are gained thanks to a new fossil from the Oligocene Salla Beds in Bolivia. The specimen described here consists of a partial rostrum, palate and postcanine teeth, and shows several generalized features (cranial and dental) in the context of the Paucituberculata. On this basis we recognize Evolestes hadrommatos gen. et sp. nov. In order to evaluate the affinities of the new taxon, we performed a phylogenetic analysis including representatives of the Caenolestidae, Pichipilus and allies (not regarded here as caenolestids), Palaeothentidae, and Abderitidae, with three outgroups. Evolestes is the basalmost 'caenolestoid', and provides clues to the morphological changes involved in the origin of caenolestids.     

THE MEANINGS OF KINSHIP AMONG THE ESE EJJA OF NORTHERN BOLIVIA

This article focuses on the construction of relatedness among an Amazonian people of northern Bolivia. In analysing the Ese Ejja's kinship terminology and practices, it engages with the widespread stress on the processual nature of relatedness encountered in Amazonian studies. The article shows that, for the Ese Ejja, kinship relations are made through shared practices, although in some important respects kinship is considered to be given at birth. Given kinship is considered fixed, whereas processual kinship is open to contestation. The article argues that processual and given aspects of kinship must be considered together in order to account for local understandings of relatedness. The data presented invite further investigation into Amazonian ideas about the sharing of substance through filiation. This has important implications for the understanding of the conceptualization of cross- and parallel cousins. The article also suggests that in Amazonia otherness is not always given, as has been extensively argued, and that, in the context of Ese Ejja kinship relations, it is created through marriage and it is constantly made and undone.     

NOTES ON THE BIRDS OF THE MOLLENDO DISTRICT, SOUTHWEST PERU

An account is given of the geography and ecology of the Mollendo district, Southwest Peru, followed by a systematic list of the species recorded there over a period of 16 years' residence.
The following species are recorded, apparently for the first time, from the south coast of Peru: Pachyptila belcheri, P. desolata, Florida caerulea, Butorides striatus, Bubulcus ibis, Plegadis chihi, Himantopus himantopus, Micropalama himantopus, Chaetura pelagica, Petrochelidon pyrrhonota, Riparia riparia and Pheucticus chrysopeplus .     

MORPHOLOGICAL STUDIES OF LYMNAEID SNAILS FROM THE HUMAN FASCIOLIASIS ENDEMIC ZONE OF BOLIVIA

The taxonomic position of the Lymnaeidae from the BolivianAltiplano has been unclear. On the basis of conchological characters,some authors reported two species from this area, Lymnaea viatrix andL. cubensis while others, considering also anatomical characters,considered L. viatrix as a synonym of L. cubensis. More recentstudies demonstrated genetic identity between the Bolivian lymnaeidsand L. truncatula from the Iberian Peninsula. Populations recognizedas L. cubensis correspond to a distinct genetic group, but geneticinformation was not available for L. viatrix. In the light ofthese genetic results, a morphometric study of both the shell (usingRaupian parameters) and male reproductive system was carried outof L. cubensis from Cuba (type locality), Dominican Republic,Guadeloupe and Venezuela, and of L. truncatula from Bolivia,France, Portugal, Spain and Morocco. Syntypes of L. viatrixfrom Argentina (var. A. ventricosa) and specimens of L. viatrix(var. B. elongata) from the type locality, Peru, were also studied(conchological characters only). The conchological study showedthe presence of a large amount of variability between populations.This variability was not congruent with genetic results. Alarge amount of variability was also found using anatomicalcharacters of the male reproductive system and all of them clearlyseparate L. cubensis from L. truncatula independently from geographicalorigin. Thus anatomical characters, unlike conchological parameters,do differentiate taxonomic species inferred from genetic studies. (Received 11 September 1997; accepted 5 March 1999)     

哈尔滨地区第四纪孢粉分析及其在地质学和植物学上的意义

本文依据哈尔滨地区不同地貌单元内三个钻孔和三个自然剖面孢粉分析资料,结合古地磁测试,热释光和放射性碳素年令测定,进行钻孔和剖面间对比,初步建立起哈尔滨地区第四纪孢粉组合特征,进而讨论了哈尔滨地区第四纪以来植物群发展和气候变化。     

THE EXTRAORDINARY TRILOBITE FENESTRASPIS (DALMANITIDAE, SYNPHORIINAE) FROM THE LOWER DEVONIAN OF BOLIVIA

Abstract:  The hitherto poorly known, monotypic trilobite genus Fenestraspis from the Lower Devonian of Bolivia is revised and its original assignment to the Synphoriinae supported. The thoracic morphology of the genus remains very poorly known. Fenestraspis is morphologically unusual because of the development of extensive fenestrae in the pleural region of the pygidium and apparently of the thorax; the presence of upwardly directed spines on the cephalon, thorax and pygidium; and the exceptionally large and highly elevated eyes with the palpebral rim projecting outwards above the visual surface. The function of the fenestrae remains uncertain. If they formed openings in the body of the trilobite in life they may have allowed circulation of oxygenated water to the limb exites so that respiration could have been maintained while the trilobite was enrolled. If they were covered with a flexible membrane, they may have been secondary respiratory structures or had a sensory function. The Synphoriinae is regarded as a subfamily of the Dalmanitidae rather than as an independent family of the Dalmanitoidea as proposed by some authors. The type species of the poorly known monotypic genus Dalmanitoides from the Lower Devonian of Argentina is illustrated photographically for the first time and compared with Fenestraspis .     

THE DISTRIBUTION OF RISSO'S DOLPHIN (GRAMPUS GRISEUS) WITH RESPECT TO THE PHYSIOGRAPHY OF THE NORTHERN GULF OF MEXICO

The distribution of Risso's dolphin ( Grampus griseus ) was examined with respect to two physiographic variables, water depth and depth gradient (sea floor slope), in the northern Gulf of Mexico, using shipboard and aerial survey data collected from 1992 to 1994. Univariate x² analyses demonstrated that Risso's dolphins are distributed non-uniformly with respect to both depth and depth gradient. A bivariate analysis of the shipboard data indicated that Risso's dolphins utilize the steep sections of the upper continental slope in the northern Gulf of Mexico. This narrow core habitat is in waters bounded by the 350-m and 975-m₁ isobaths with depth gradients greater than 24 m per 1.1 km and consists of only 2% of the surface area of the entire Gulf of Mexico. Sighting rates inside this region were nearly 5 and 6 times the average for the shipboard and aerial surveys, respectively. Of the groups sighted outside this region, 40% (shipboard) and 73% (aerial) were encountered within 5 km of it. Since it is unlikely that the physiography alone can attract dolphins, oceanographic mechanisms that may concentrate prey along the steep upper continental slope are discussed. The implications of this distribution, including potential prey species, foraging strategies, and impacts of proposed mineral exploration and development, are also considered.     

东南亚及其邻近岛屿钝头蛇亚科Pareinae的谱系发育及其与地质演变的关系

钝头蛇亚科Pareinae隶属游蛇科Colubridae分布于10°S—35°N,80°—125°E的东南亚及其邻近岛屿,是具有吻钝,无颏沟和上颌骨前端无齿等特殊性状的唯一类群,原记载共2属16种。经全面分类清理后,该类群共有18种,分别隶属Pareas Wagler,Aplopeltura Dumeril et Bibron和Internatus gen.nov.三属,其中Pareas具派生性状最少为最原始,Aplopeltura具派生性状最多为最特化。Aplopeltura和Internatus可能分别源自Pareas的某一级或不同级的祖先,可能是第四纪大冰期时先后从大陆迁入马来半岛、苏门答腊、婆罗洲、爪哇和菲律宾南部,然后在间冰期和冰后期因适应岛屿环境而特化成的新类群。