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showing 10 items of 38174 documents
Athenacrinus n. gen. and other early echinoderm taxa inform crinoid origin and arm evolution
2020
AbstractIntermediate morphologies of a new fossil crinoid shed light on the pathway by which crinoids acquired their distinctive arms. Apomorphies originating deep in echinoderm history among early nonblastozoan pentaradiate echinoderms distinguish Tremadocian (earliest Ordovician) crinoid arms from later taxa. The brachial series is separated from the ambulacra, part of the axial skeleton, by lateral plate fields. Cover plates are arrayed in two tiers, and floor plates expressed podial basins and pores. Later during the Early Ordovician, floor plates contacted and nestled into brachials, then were unexpressed as stereom elements entirely and cover plates were reduced to a single tier. Inco…
Observations on the postcranial anatomy of Hoplitomeryx (Mammalia, Ruminantia, Hoplitomerycidae) from the Miocene of the Apulia Platform (Italy)
2016
The untypical ruminants of the Apulia Platform (central and southeastern Italy), originally accommodated in the genus Hoplitomeryx, have been recently revised. The Scontrone (Abruzzo, central Italy) representatives were included in a new genus, Scontromeryx, with the addition of a new species, Scontromeryx mazzai. In contrast, the Gargano ones were left in Hoplitomeryx, but also in this case with the addition of three new species, Hoplitomeryx devosi, H. macpheei, and H. kriegsmani, described on postcranial remains and based on body mass calculations and using a size class scoring technique. The results of the present study show that Scontromeryx is invalid, that S. mazzai is imperfectly de…
Functional assessment of morphological homoplasy in stem-gnathostomes
2021
Osteostraci and Galeaspida are stem-gnathostomes, occupying a key phylogenetic position for resolving the nature of the jawless ancestor from which jawed vertebrates evolved more than 400 million years ago. Both groups are characterized by the presence of rigid headshields that share a number of common morphological traits, in some cases hindering the resolution of their interrelationships and the exact nature of their affinities with jawed vertebrates. Here, we explore the morphological and functional diversity of osteostracan and galeaspid headshields using an innovative approach that combines geometric morphometrics and computational fluid dynamics, thereby constraining the underlying fa…
Systematic revision of the Late Miocene sabre-toothed felid Paramachaerodus in Spain
2010
Abstract: A systematic revision of the sabre-toothed cat genus Paramachaerodus Pilgrim, 1913 is presented. Two species are recognized within Paramachaerodus, Pa. orientalis, and Pa. maximiliani, and the genus Promegantereon Kretzoi, 1938 is retrieved to include Promegantereon ogygia. Material from the Turolian Spanish localities of Crevillente-2 (MN 11, Alicante) and Las Casiones (MN 13, Teruel), which was previously assigned to Paramachaerodus, is now included in the tribe Metailurini. The exceptional discoveries at the Spanish Vallesian (MN 10, Madrid) fossil site of Batallones-1 have made it possible to characterize the dentition and cranial anatomy of a previously very poorly known mac…
Heteroptera of Lebanon. II.Phytocoris(Exophytocoris)RaunolinnavuoriiSp. Nov. from the Horsh Ehden Nature Reserve and Adjacent Areas (Hemiptera: Heter…
2016
Abstract A new species of Phytocoris (Heteroptera: Miridae: Mirinae: Mirini), P. (Exophytocoris) raunolinnavuorii sp. nov., is described and illustrated from Lebanon. The new species, easily distinguished from all the other species of the subgenus by its coloration and male genitalia, belongs to the Phytocoris pinihalepensis-group. The new species lives on the conifers Abies cilicica (Antoine & Kotschy) Carriere (Pinaceae) and Juniperus excelsa M. Bieb. (Cupressaceae).
Development of Rich Fen on the SE Baltic Coast, Latvia, during the Last 7500 Years, Using Paleoecological Proxies: Implications for Plant Community D…
2016
We present the paleoecological development of a rich fen located in the dune area on the SE Baltic coast, during the last 7500 years. The Apsuciems Mire hosts rare and endangered plant communities in Europe, such as Schoenus ferrugineus and Cladium mariscus. Analysis at high-resolution of plant macroremains in two peat cores was carried out to reconstruct local vegetation succession and fluctuations in moisture availability on the peatland, while a pollen record was developed to reconstruct plant succession, moisture variability and human activity at the regional scale. Based on the presence or the absence of macroremains of plants that occur in wet habitat e.g. Cladium mariscus, Schoenople…
Does quality of winter food affect spring condition and breeding in female bank voles (Clethrionomys glareolus)?
2004
We studied the effects of food supplementation on 16 bank vole populations in spring. We manipulated food quantity and quality in eight populations that were enclosed and eight other populations th...
Values and challenges in the assessment of coprophilous fungi according to the IUCN Red List criteria: the case study of Poronia punctata (Xylariales…
2020
Coprophilous fungi are specialized microorganisms, playing key roles in ecosystems and in several other contexts, whose protection requires more substantial efforts. This paper aims to highlight and discuss valuable and critical aspects faced during the process of the threat status assessment of Poronia punctata, providing inspirations for future conservation actions.
Cranial bone histology of Metoposaurus krasiejowensis (Amphibia, Temnospondyli) from the Late Triassic of Poland
2016
In this study, 21 skull bones ofMetoposaurus krasiejowensisfrom the Late Triassic of Poland were investigated histologically. Dermal bones show a diploë structure, with an ornamented external surface. The ridges consist of mostly well vascularized parallel-fibered bone; the valleys are built of an avascular layer of lamellar bone. The thick middle region consists of cancellous bone, with varying porosity. The thin and less vascularized internal cortex consists of parallel-fibered bone. The numerous Sharpey’s fibers and ISF are present in all bones. The cyclicity of growth is manifested as an alternation of thick, avascular annuli and high vascularized zones as well as a sequence of resting …
Rhynchophorus ferrugineus: Behavior, Ecology, and Communication
2017
Red palm weevil (RPW) ecology is characterized by the adults' ability to aggregate on palms. The aggregation process has the functions of protection, feeding, and reproduction for the individuals. Semiochemicals and visual cues strongly influence this behavior at intraspecific and interspecific levels. Adults actively fly over long distances, following chemical cues, such as aggregation pheromone and host plant odor, or visual cues to colonize a new host. The aggregation pheromone of RPW is a male-produced mixture of 4-methyl-5-nonanol (major component) and the related ketone 4-methyl-5-nonanone (minor component). These compounds are largely used in the field to lure males and especially fe…