E. Landing - Academia.edu (original) (raw)

Papers by E. Landing

Palaeontologische Zeitschrift, Dec 10, 2021

Eccaparadoxides is a geographically widely distributed trilobite genus that occurs in the middle ... more Eccaparadoxides is a geographically widely distributed trilobite genus that occurs in the middle part of the Cambrian System. However, the systematically important morphologic characteristics that can be used to differentiate taxa are often problematical in their application. A review of the large number (over 30) of significant species or forms assigned to Eccaparadoxides clearly indicates that only the pygidia offer fairly reliable morphologic criteria that can be used taxonomically and phylogenetically. The pygidia allow for recognition of four different morphological groups (pusillus, lamellatus, pradoanus and asturianus) of which the asturianus group can only be questionably assigned to the genus. Species known only from cranidia cannot be assigned to Eccaparadoxides with certainty. This study refines the biostratigraphy for the interval from the upper Wuliuan to the middle Drumian and shows that this interval brackets the range of most Eccaparadoxides species. The genera or subgenera Baltoparadoxides, Rejkocephalus and Macrocerca are evaluated. Eccaparadoxides zelus, E. epimetheus and Eccaparadoxides? hestia are newly proposed species.

the fossil record of complex animal behaviour a stratigraphical

Journal of Paleontology, 1976

Episodes, 2018

Research into the long-recognized 'Cambrian Explosion' of animal life (e.g., Lipps and Signor, 19... more Research into the long-recognized 'Cambrian Explosion' of animal life (e.g., Lipps and Signor, 1992; Briggs, 2015) has, in recent decades, increasingly sought to resolve the interplay between evolutionary, geochemical and environmental changes that occurred over an extended Ediacaran to Cambrian transitional interval. This wider

Northeastern Geology and Environmental Sciences, 1998

Special Paper 304: Avalonian and related peri-Gondwanan terranes of the Circum-North Atlantic, 1996

Unambiguous definition of the Avalon terrane and deter-mination of its size, shape, and proximity... more Unambiguous definition of the Avalon terrane and deter-mination of its size, shape, and proximity to other continents and terranes are vital to latest PrecambrianEarly Paleozoic paleogeographic reconstructions. Three features distinguish the fault-bounded fragments of Avalon along ...

Bulletin of Geosciences, 2011

... Ed Landing, New York State Museum, 222 Madison Avenue, Albany, NY, 12230, USA; elanding @mail... more ... Ed Landing, New York State Museum, 222 Madison Avenue, Albany, NY, 12230, USA; elanding @mail.nysed.gov • Stephen R. Westrop, Oklahoma Museum ... from relatively ef-faced to strongly furrowed cranidia and pygidia) in L. americanus than that allowed by Ludvigsen et al. ...

Journal of Paleontology, 1980

... The locality is one of three small shore outcrops of Cambrian sandstones, which were 753 z 4&... more ... The locality is one of three small shore outcrops of Cambrian sandstones, which were 753 z 4< z ur < z 5 0 o z < < I :2 uJ I-cr p . a0 z I 0 (1) z I< co z U 0 ... - v -V, - IL Page 3. 754 ~~~~~ED LANDING CHESLEY DRIVE (CD) -AC-20.50(.5) -AC-12(2.O) -AC-lO0(5.4) -AC-5.3(4.7) ...

Journal of Paleontology, 1974

... In addition, Poulsen re-covered 50 cusps of Hertzina danica Poulsen from the Kalby Clay (Toma... more ... In addition, Poulsen re-covered 50 cusps of Hertzina danica Poulsen from the Kalby Clay (Tomagnostus fissus-Ptychagnostus atavus Zone of the P ... for description of two Lower Cambrian sections and their fos-sils which are located at the north end of the Troy High School ...

Palaeogeography, Palaeoclimatology, Palaeoecology, 2010

ABSTRACT

Palaeogeography, Palaeoclimatology, Palaeoecology, 2006

Exotic lithofacies and faunas have long been known from Snake Hill, eastern New York, USA. The fa... more Exotic lithofacies and faunas have long been known from Snake Hill, eastern New York, USA. The faunally diverse, sandstonedominated Upper Ordovician succession at Snake Hill sharply contrasts with surrounding tectonized sparsely fossiliferous distal shale. Re-examination of the Snake Hill section shows that it is a storm-and wave-dominated near-shore facies with a benthic fauna analogous to that of the younger Lorraine Group (Ashgillian) of central New York, and to that of the upper Martinsburg Group (upper Caradocian) of eastern Pennsylvania. Orthograptus ruedemanni Chron graptolites indicate that the Snake Hill succession is older than the surrounding tectonized, deep-water shale (Climacograptus spiniferous Chron). Snake Hill is best interpreted as a parautochthonous block in mélange originally deposited close to the shoreline of the emergent Taconic accretionary prism. Because the Snake Hill succession is sandstone-dominated, it is inappropriate to refer mudstone-dominated facies that underlie the western margin of the Taconic allochthon in the Hudson River valley region to the Snake Hill "Shale," as has been done in the past. The thick (ca. 150 m), lithologically distinct succession at Snake Hill is therefore referred to as the "Snake Hill Formation." The Snake Hill Formation is the only known example of proximal, near-shore facies deposited on the western side of the outer Taconic arc, and represents easternmost deposition in the Taconic foreland basin. The Snake Hill Formation is a unique occurrence, and thus is restricted to its type locality at Snake Hill, New York.

Palaeogeography, Palaeoclimatology, Palaeoecology, 2012

Pyritized, elongate, conical conchs of "Allatheca" degeeri s.l. are common in dysoxic, dark gray ... more Pyritized, elongate, conical conchs of "Allatheca" degeeri s.l. are common in dysoxic, dark gray mudstone intervals in the Early Cambrian (upper Terreneuvian-Series 2 boundary interval) Cuslett Formation at Keels, eastern Newfoundland. Wave-oriented, horizontal specimens are most abundant in this cool-water, high latitude, offshore shelf facies of the Early Palaeozoic Avalon microcontinent. Based on conch morphology, shell microstructure, and the operculum, the species is an orthothecid hyolith. Comparison with the sizes of the early shells of planktic gastropods indicates a non-planktic life mode of "A." degeeri s.l. hatchlings, although buoyancy calculations show that small juveniles with septate conchs to ca. 17 mm long could have been nektic/planktic. If smaller "A." degeeri s.l. individuals had a non-benthic mode of life, they and pseudoconodonts were the oldest skeletalized pelagic/nektic animals in the Cambrian Evolutionary Radiation. Most "A." degeeri s.l. conchs at Keels are horizontally embedded and show a bimodal, wave-determined orientation, but about 10% of the large conchs are vertically embedded with their aperture down. As larger shells were not neutrally buoyant, the vertical orientations of about 10% of the conchs suggests an infaunal, likely detritivore, life mode suggestive of a scaphopod. Available morphologic and taphonomic evidence suggests that the vertically embedded conchs are in situ remains of dead benthic animals that colonized the bottom in better oxygenated intervals. Based on the current knowledge of Early Palaeozoic hyolith and cephalopod larval and adult morphologies, existing hypotheses of a planktic origin of cephalopods from hyolith ancestors are evaluated, and no evidence for such an evolutionary relationship is concluded to exist.

Journal of Sedimentary Research, 1978

Early diagenetic dissolution removed aragonitic molluscan debris which served as nuclei for ooids... more Early diagenetic dissolution removed aragonitic molluscan debris which served as nuclei for ooids in the Jurassic Twin Creek Formation in northwestern Wyoming. The resulting hollow elliptical shells were subsequently crushed during burial and compaction to produce the crushed ooids typical of this Jurassic unit. Alternatively, ooids with nuclei composed of calcite in the form of cfinoidal, foraminifera, and molluscan debris remained intact and were unaffected during this early burial event. Precompactional dissolution of aragonitic ooid nuclei is indicated by flattened ooids and confirmed by the orientation of fractures developed in the conical coatings. Hollow ooids were flattened by tensional microfracturmg of the cortical exterior in planes oriented parallel and perpendicular to bedding. Boring by miernendoliths preceding and accompanying ooid formation provided additional permeability for carbonate diffusion from ooid interiors during their dissolution. Cortices of Twin Creek ooids are now composed of radial calcite. Textural evidence suggests that both the fabric and mineralogy of the radial calcite are primary. This evidence supports the postulate of Sorby (1879) and Sandberg (1975) that radial fabric in many ancient calcite oolites is primary and not related to postdepositional diagenetic modification.

Journal of Paleontology, 2007

The Tribes Hill Formation (upper Skullrockian) of New York records the earliest Ordovician divers... more The Tribes Hill Formation (upper Skullrockian) of New York records the earliest Ordovician diversification of cephalopods, in particular ellesmerocerids, on the east Laurentian, shallow carbonate platform. Revision of this cephalopod fauna on the basis of approximately 430 specimens collected across eastern New York has led to new information on inter-and intraspecific variation of the taxa and extensive synonymization of species-level taxa. The Ellesmeroceratidae and Protocycloceratidae, Ellesmeroceras, and Eremoceras are emended, Eorudolfoceras n. gen. and Dakeoceras champlainense n. sp. are erected. A rank abundance plot of the 342 specimens at a locality in the Lake Champlain lowlands provides information on the community structure of the nautiloid fauna, where small orthoconic taxa are shown to dominate strongly. The small orthocone Ectenolites was the most common genus in terms of total occurrences, was the most paleogeographically widespread genus, and was the only genus to cross the Cambrian-Ordovician boundary.

Journal of Paleontology, 2009

Cambrian Cephalopods are presently reported only from tropical, carbonate platform successions th... more Cambrian Cephalopods are presently reported only from tropical, carbonate platform successions that occur on a number of paleocontinents. Outside of West Gondwanan occurrences on the eastern Sino-Korean Platform in China, the record of Cambrian cephalopods is limited, and information on the early evolution and habitats of this molluscan class has grown slowly over the last century.