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Skull size variation in the orange mouse opossum Marmosa xerophila Handley and Gordon, 1979 in Venezuela was analysed by sex and geographic location. Morphometric relationships between the species and the closely related M. robinsoni Bangs, 1898 were also studied. Results showed that M. xerophila is a sexually dimorphic and geo­graphically homogeneous species. Males had larger skulls than females, although dimorphism was mainly related to length, height, and some dental parameters. Inter­specific comparisons revealed that M. xerophila has a smaller skull than M. robinsoni, even in the sympatric area where the smallest specimens of M. robinsoni occur. Dis­criminant function analyses between these species, for males and females separately, provided accurate classification functions that allowed correct specific determination. In Venezuela, M. xerophila lives in arid lands with xerophilous thorny woodland and scrub, up to 90 m above see level.
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We erect a new genus, Elongatolucina, for distinctive large, elongate lucinid bivalve specimens from Miocene sediments from Venezuela. We interpret Elongatolucina to have had a chemosymbiotic mode of life and it may have been seep−restricted. Cryptolucina elassodyseides from Eocene hydrocarbon seep sites in Washington State, USA is incorporated in Elongatolucina.
The diet of Cryptotis meridensis Thomas, 1898 was studied by analysing stomach contents of 55 shrews collected by pitfall trapping in the cloud forest of Monte Zerpa, Mérida, Venezuela. The aims of the study were to describe the diet of this unknown tropical species and test the prediction that this species should be more of a subterranean feeder according to its morphological adaptations. The diet was composed of 35 different prey taita distributed in six invertebrate classes (Gastropoda, Annelida, Arachnida, Crustacea, Myriapoda and Insecta). The most important components of the diet were hypogeal invertebrates: Oligochaeta, Gastropoda, Theraposidae, Isopoda, Scolopendridae, Phasmatidae, Blatiidae, Lepidoptera larvae and pupae, Diptera larvae, adult Carabidae, Staphilinidae, Elateridae larvae, Passalidae and Scarabaeidae larvae. Their contribution was 69.44% of the overall diet composition. Oligochaeta were the most frequent prey. Ephigeal invertebrates (Lycosidae, Acrididae, Gryllidae, adult Scarabaeidae and Lycosidae) accounted for only 27,24%. The preferences for soil invertebrates found in this study confirmed our prediction that C. meridensis uses mostly a subterranean foraging mode in accord with its morphological adaptations similar to other shrews in temperate habitats.
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Tapirs from the Pleistocene of Venezuela

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The living tapir Tapirus terrestrisis widely distributed in Venezuela, occurring mainly south of the Orinoco, while being absent from arid, high Andean and insular areas. Here, we describe new material of fossil tapirs from two Pleistocene localities of Venezuela: Zumbador Cave and El Breal de Orocual. Based on its size and morphology, the material from Zumbador Cave (skull, mandible and postcrania) is assigned to the extant T. terrestris, and represents the most northwestern fossil record of this species in South America. By contrast, the remains from the tar seep of El Breal de Orocual are more gracile, and differ from T. terrestris and other fossil and living species from South America in the presence of a metastylid on the lower cheek teeth. We tentatively assign the latter remains to Tapirussp., based on juvenile and isolated dentary material. However, the possibility that these specimens may represent a new species or an immigrant from North America cannot be completely excluded.
An examination of four specimens of the common caiman, Caiman crocodilus (L.), from small lakes (“lagunas”) in the surroundings of Boca de Anaro on the Suripá River, State of Barinas, Venezuela revealed the presence of two nematode species, Brevimulticaecum baylisi (Travassos, 1933) and Micropleura vazi Travassos, 1933. The finding of the latter species represents its first record from Venezuela and from the Orinoco River drainage system. A detailed study of their morphology, including SEM, made it possible to establish some new, taxonomically important morphological features of these species (e.g., the presence of cervical alae and the exact number and arrangement of male caudal papillae in B. baylisi, the number and arrangement of cephalic papillae and the structure of cuticular ornamentation in M. vazi). Brevimulticaecum sp. infective larvae reported by Moravec et al. (1997) from fishes originating from the same locality as the caimans are now considered to belong to B. baylisi.
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