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EN
The Family Neokoninckophyllidae and its type genus Neokoninckophyllum Fomichev, 1939 (type species: N. tanaicum Fomichev, 1939) are discussed and emended. In addition, the genera Orygmophyllum Fomichev, 1953 and Yuanophylloides Fomichev, 1953, originally included in the Families Campophyllidae Wedekind, 1922 and Lophophyllidae Grabau, 1928, respectively, are emended as well and transferred to the Neokoninckophyllidae. Two early Bashkirian species, viz. Yuanophylloides rectus (Vassilyuk in Aizenverg et al., 1983) and Y. inauditus (Moore and Jeffords, 1945), and the Moscovian Neokoninckophyllum sp. nov. are described on the basis of new collections from the Donets Basin. Neokoninckophyllum tanaicum, Yuanophylloides gorskyi Fomichev, 1953 (both Moscovian in age) and Y. cruciformis Fomichev, 1953 (latest Bashkirian), are redescribed on the basis of peels taken from Fomichev’s (1953) type specimens. Derivation of the Family Neokoninckophyllidae from the Subfamily Dibunophyllinae Wang, 1950 is postulated and phylogenetic links within the former are hinted at. The occurrence of Yuanophylloides inauditus in both the Donets Basin and the Western Interior Province of North America points to marine communication between those areas during the Bashkirian. The slightly earlier appearance of the oldest neokoninckophyllids in the Donets Basin, in comparison to North America (i.e., R1 vs R2 ammonoid biozones), documents the common roots and monophyletic development of the Neokoninckophyllidae in both areas.
EN
Seven genera (one new), belonging to four subfamilies, seven named species (six new), four species left in open nomenclature and two specimens included in this paper as unnamed Aulophyllidae are described from strata ranging from the lowermost Bashkirian Limestone D510 to the lower Bashkirian Limestone F1. A new genus: Voragoaxum and six new species: Dibunophyllum medium, Dibunophylloides columnatus, D. paulus, D. similis, Voragoaxum cavum and Rozkowskia lenta are introduced. Comparison of the ontogeny of the earliest Bashkirian species of Nina Fedorowski, 2017a and Dibunophylloides Fomichev, 1953 suggest the derivation by descent of the Family Bothrophyllidae from the Subfamily Dibunophyllinae. This means that true bothrophylla are absent in the Mississippian strata of the Western European Province and, perhaps, in the contemporaneous strata of other areas as well.
EN
The ammonoid "Trachyphyllites costatum" Arthaber (1927), based on a single specimen from an erratic boulder of presumed Late Triassic (Norian age) from Timor, (Indonesia), was originally described as a phylloceratid but later recognized as a true lytoceratid by Basse (1952) and Schindewolf (1961), and used by Wiedmann (1966a, 1966b, 1970) to support his idea of a polyphyletic origin of the post-Triassic ammonoids and of the Late Triassic roots of the lytoceratids. New collections of additional specimens and associated taxa from other erratic boulders in the type locality have confirmed observations (Tozer 1971; Krystyn 1978) that the age of the original boulder was misinterpreted, and have shown that "Trachyphyllites" is actually of Early Jurassic (Hettangian) age. An unpublished generic revision of the entire superfamily Lytoceratoidea by Hoffmann (2009) has shown that "Trachyphyllites costatum Arthaber" is a junior synonym of Analytoceras hermanni (Gumbel, 1861), a taxon thought by Wahner (1894) to be a subjective synonym of Analytoceras articulatum (J. Sowerby, 1831) We reestablish the species Analytoceras hermanni (Gumbel, 1861) for Analytoceras articulatum "Type B" (Wahner 1894), which is characterized by a wide umbilicus and a small whorl expansion rate. The morphologically distinct "Type A" (Wahner 1894) corresponds to the type species of Analytoceras, A. articulatum (J. Sowerby, 1831). A revised phylogeny of the Early Jurassic lytoceratids is presented.
EN
As many hybodont sharks are known solely from their teeth, this investigation approaches the phylogeny of the group with an emphasis on tooth morphology and dentitional patterns. The preliminary results presented here suggest that at least four different lineages of hybodont sharks occurred in the Mesozoic. Dentitional characters imply a close relationship within the Lonchidiidae (Lonchidion, Vectiselachos, Parvodus, and tentatively Hylaeobatis), within the Hybodontinae (Hybodus and Egertonodus) and in another, unnamed subfamily of the Hybodontidae, including Planohybodus, Secarodus and Priohybodus. There is also weak support for a grouping of Acrodus, Asteracanthus and Palaeobates in the Acrodontinae, while Lissodus is left without family designation due to a rather unique dentition and cephalic spine morphology. "Polyacrodus" is considered a nomen dubium as there are no characters to diagnose the genus based on the type species.
EN
A point and a straight line are fundamental objects of Euclidean geometry which is taught at basic and secondary schools. Philosophers meditated on the nature of a point and a straight line long before Euclid (from the 6th century BC). But it was Euclid (about 325-265 BC) who delimited the concept of a point and a straight line (and others) in the First book of his Elements (Stocheia) by means of a definition. The phylogenesis of a point and its relation to a straight line is marked out by names such as Viéte, Kepler, Leibniz, Newton, Bolzano and Cantor. Students meet the concept of a point before they start to create their geometrical structures. Our analysis will try to show that there is a strong parallel between the ontogenetic and phylogenetic aspects of the conception of a point and its relation to a straight line, a ray and/or a segment.
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