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Registros recuperados: 82 | |
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Rabaey, D.; Lens, F.; Huysmans, S.; Smets, E.; Jansen, S.. |
Recent micromorphological observations of angiosperm pit membranes have extended the number and range of taxa with pseudo-tori in tracheary elements. This study investigates at ultrastructural level (TEM) the development of pseudo-tori in the unrelated Malus yunnanensis, Ligustrum vulgare, Pittosporum tenuifolium, and Vaccinium myrtillus in order to determine whether these plasmodesmata associated thickenings have a similar developmental pattern across flowering plants. At early ontogenetic stages, the formation of a primary thickening was observed, resulting from swelling of the pit membrane in fibre-tracheids and vesselelements. Since plasmodesmata appear to be frequently, but not always, associated with these primary pit membrane thickenings, it remains... |
Tipo: Article / Letter to the editor |
Palavras-chave: Ontogeny; Pseudo-torus; Tracheary element; Pit membrane; Bordered pit; Wood ultrastructure; 42.56. |
Ano: 2008 |
URL: http://www.repository.naturalis.nl/record/430078 |
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Marjanovic, D.; Laurin, M.. |
The origin of frogs, salamanders and caecilians is controversial. McGowan published an original hypothesis on lissamphibian origins in 2002 (McGowan, 2002, Zoological Journal of the Linnean Society, 135: 1-32), stating that Gymnophiona was nested inside the 'microsaurian' lepospondyls, this clade was the sister-group of a caudate-salientian-albanerpetontid clade, and both were nested inside the dissorophoid temnospondyls. We have investigated McGowan's data matrix and isagree with the scoring of 35% of the cells. All taxa and all but two characters are affected. In some cases, we have a different interpretation about correspondence between morphology and character states, or we delimit states differently (or use information that was unknown in 2002). In... |
Tipo: Article / Letter to the editor |
Palavras-chave: Albanerpetontidae; Brachydectes; Coding; Continuous characters; Data matrix; Gerobatrachus; Gymnophioniformes; Gymnophionomorpha; Lissamphibia; Lysorophia; Morphology; Ontogeny; Paleontology; Phylogeny; Scoring; Stepmatrix gap-weighting; 42.82. |
Ano: 2008 |
URL: http://www.repository.naturalis.nl/record/289109 |
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Nayrolles, Pierre. |
The following three species are redescribed: Sminthurus viridis (Linnaeus, 1758), Sminthurus nigromaculatus Tullberg, 1871, and Sminthurus multipunctatus Schäffer, 1896. Four new species are described from France and Spain: Sminthurus bourgeoisi n. sp., Sminthurus bozoulensis n. sp., Sminthurus leucomelanus n.sp.,and Sminthurus hispanicus n. sp. The importance of the ontogeny of chaetotaxy is stressed. Indeed, not all species acquire the secondary chaetotaxy in the same instar, and for these characters the most informative instar is not the adult but the third juvenile instar. The study of such characters involves the clustering of similar characters. A short discussion is given about this issue (selection of characters and clustering criteria). |
Tipo: Article / Letter to the editor |
Palavras-chave: Collembola; Symphypleona; Sminthurus; Chaetotaxy; New species; Taxonomy; Ontogeny; France; Spain. |
Ano: 1995 |
URL: http://www.repository.naturalis.nl/record/503948 |
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DELCOURT,RAFAEL. |
ABSTRACT Daspletosaurus is a Campanian genus of Tyrannosauridae from North America. This genus occupied the same geographic area of Albertosaurus, but remains of Albertosaurus are more abundant than Daspletosaurus. Here is described a subadult maxilla (AMNH FARB 5477) of Daspletosaurus sp. from Montana (USA) and possibly from the Two Medicine Formation. The description is based on Carr (1999) that described cranial ontogenetic variations in tyrannosaurids. The maxilla belongs to the ontogenetic Stage 3 sensu Carr (1999), in which the maxilla is thick, the lateral surface of the bone well sculptured, and the maxillary fenestra is subcircular and well separated from the anterior edge of antorbital fossa. Possibly there were more than one species of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Daspletosaurus; Ontogeny; North America; Montana. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0031-10492017000900113 |
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Hohl,Leandro dos S. L; Sicuro,Fernando L; Azorit,Concepción; Carrasco,Rafael; Rocha-Barbosa,Oscar. |
Morphological variation of the ramus mandibulae of wild Sus scrofa was described and correlated to sex and age differences. Young forms (n=27, 15 males, 12 females) and adults (n=23, 13 males, 10 females) were analyzed through Geometric Morphometrics (2-D) to assess differences between groups. We found significant differences between age- and sex-related shape variations at ramus mandibulae level. Young wild boars present bulky angular process with backward oriented coronoid process, while adults show slender jaw vertical ramus, and orthogonally oriented coronoid process. The ramus mandibulae in female wild boars is more robust and bulky than in males. The morphological changes between young and adult forms are related to alterations in the osteo-muscular... |
Tipo: Journal article |
Palavras-chave: Mandible; Ontogeny; Sexual Dimorphism; Wild boar. |
Ano: 2014 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022014000400026 |
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Nayrolles, Pierre. |
Phylogenetic studies on several groups of arthropods, such as Acari (mites) or Collembola (springtails), make wide use of chaetotaxy. Chaetotaxic characters, besides being morphological features (setal shape), often have a binary nature, that is presence vs. absence. A seta can be variable in a population, and one may attribute a presence probability to this seta. In fact, the presence probability should be defined for each instar. One might think that a variable seta corresponds to a polymorphism (e.g., two or more alleles in a population); in fact, setal variability should be regarded as the result of a propensity intrinsic to individuals, i.e., a potentiality being expressed at random among specimens. The phenomenon known as lateral inhibition explains... |
Tipo: Article / Letter to the editor |
Palavras-chave: Ontogeny; Phytogeny; Chaetotaxy; Probabilistic organs; Ontogenetic trajectories; Arthropods; Collembola; Symphypleona. |
Ano: 1998 |
URL: http://www.repository.naturalis.nl/record/534360 |
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MÜLLER,RODRIGO T.. |
ABSTRACT The lagerpetid Dromomeron romeri and the theropod Tawa hallae are two dinosauromorphs from the Norian (Upper Triassic) of the Chinle Formation, situated in New Mexico, USA. However, a recent study suggests the inclusion of the holotype of D. romeri (GR 218) and paratype (GR 155) and referred (GR 235) specimens of T. hallae in an ontogenetic series of a single species. The specimens GR 218 and GR 155 include just an isolated femur, while GR235 includes femora, pelvis and tail. The inclusion of the specimens in an unique ontogenetic series relies on the putative immature condition and plastic deformation of the specimen GR 218. However, as observed here, the disparity between the femora of D. romeri and T. hallae is considerably higher than those... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chinle Formation; Dinosauria; Dinosauriformes; Lagerpetidae; Norian; Ontogeny. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652017000300835 |
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Andrade,Fernanda F.; Lima,Ariane F.; Assumpção,Lucileine; Makrakis,Sergio; Kasai,Rodrigo I. D.; Makrakis,Maristela C.. |
ABSTRACT This study described the initial development of Pseudoplatystoma reticulatum, as well as changes in growth patterns. Morphometric and meristic variables were analyzed during embryonic, larval and juvenile periods, even as allometric growth coefficients for larvae and juveniles. Eggs showed an average diameter of 1.79 mm and broad perivitelline space (23.41%). The total length (TL) of the larvae ranged from 3.05 to 25.72 mm, and the total number of myomeres ranged from 45 to 50 (preanal = 13-16 and postanal = 30-35). Initial pigmentation is poor, concentrated at the extremities of the yolk sac. In the flexion stage, the pigmentation intensifies and forms a longitudinal stripe extending from the snout to the operculum and two longitudinal stripes on... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allometric growth; Early life stages; Fish larvae; Morphology; Ontogeny. |
Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252016000200216 |
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Duarte,L.L.; Menna-Barreto,L.; Miguel,M.A.L.; Louzada,F.; Araújo,J.; Alam,M.; Areas,R.; Pedrazzoli,M.. |
Chronotype is an established concept designed to identify distinct phase relationships between the expression of circadian rhythms and external synchronizers in humans. Although it has been widely accepted that chronotype is subjected to ontogenetic modulation, there is no consensus on the interaction between age and gender. This study aimed to determine the relationship between age- and gender-related changes in the morningness-eveningness character in a large sample of people. A total of 14,650 volunteers were asked to complete the Brazilian version of the Horne and Östberg chronotype questionnaire. The data demonstrated that, on average, women were more morning-oriented than men until the age of 30 and there were no significant differences between men... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chronotype; Gender; Ontogeny; Circadian rhythms; Sleep timing. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2014000400316 |
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Hartog, J.C. den; Ocaña, O.; Brito, A.. |
Species of Corallimorpharia collected during the CANCAP expeditions in the south-eastern part of the North Atlantic are described and discussed, altogether five species belonging to three genera of Corallimorphidae: the shallow water forms Corynactis viridis Allman, 1846, Pseudocorynactis caribbeorum den Hartog, 1980, and P. caboverdensis spec. nov., and the deep-sea forms Corallimorphus cf. atlanticus Carlgren, 1934, and C. ingens Gravier, 1918. The taxonomic status of the representatives of the genus Corynactis Allman, 1846, is discussed. All temperate to subtropical species described so far belong to a group of closely related allopatric taxa forming the Corynactis viridis-complex, possibly representing a single species only. The colours of Corynactis... |
Tipo: Article / Letter to the editor |
Palavras-chave: Corallimorpharia; Corallimorphidae; Corallimorphus; Corynactis; Pseudocorynactis; Sideractis; Nectactis; Nematocysts; Ontogeny; Distribution; Feeding; CANCAP-project; South-eastern North Atlantic; Macaronesia.; 42.72. |
Ano: 1993 |
URL: http://www.repository.naturalis.nl/record/317646 |
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Betti, P.. |
The ontogeny of the first stages of development of hake (Merluccius hubbsi)considering yolksac larvae, preflexion larvae, larvae in flexion, postflexion larvae, transformation larvae and posttransition juveniles, is described. Fish larvae and posttransition juveniles were collected in the north Patagonian area, between 42° and 46°S, from surroundings of the coast to the 100 m isobath (Argentine Sea, SW Atlantic). The larvae were collected between December and February, and the posttransition juveniles, in April and June since 1989 to 2004. The morphometrics variables and pigmentation were recorded in 127 larvae y 41 posttransition juveniles ranging in total length (TL)from 2.0 to 35.0 mm. Additionally, the openning of the mouth was calculated and... |
Tipo: Theses and Dissertations |
Palavras-chave: Fish larvae; Juveniles; Ontogeny; Morphogenesis; Morphogenesis; Fish larvae; Juveniles; Ontogeny; Http://aims.fao.org/aos/agrovoc/c_4943; Http://aims.fao.org/aos/agrovoc/c_2924; Http://aims.fao.org/aos/agrovoc/c_25393; Http://aims.fao.org/aos/agrovoc/c_12941. |
Ano: 2005 |
URL: http://hdl.handle.net/1834/2599 |
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Sousa,Wilson Treger Zydowicz de; Severi,William. |
The cynodontid fish Rhaphiodon vulpinus Agassiz, 1829, known as "peixe-cachorro", is the only species of the family oceurring in the Pantanal of Mato Grosso. The initial development of its larvae was characterized, based on material collected with a 500 µm mesh size plankton-net, in several biotopes of the Pantanal of Barão de Melgaço, State of Mato Grosso, Central Brazil. The analysis was carried out with 72 larvae with standard length (SL) between 4.7 and 13.8 mm. The morphometric measurements varied positively with standard length, and body proportions ranged 8.1-17.8% for head length (HL), 6.2-10.1% for body height, and 63.673.5%, 16.8-21.6%, and 61.8-78.2% SL, respectively for pre-dorsal, pre-pectoral and pre-anal distances. The eye diameter varied... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cynodontidae; Rhaphiodon vulpinus; Larval development; Ontogeny; Morphometrics. |
Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752002000100006 |
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MONTEIRO,WALKYRIA ROSSI; CASTRO,MARÍLIA DE MORAES; MAZZONI-VIVEIROS,SOLANGE CRISTINA; MAHLBERG,PAUL GORDON. |
The ten-celled biseriate glandular trichome of Stevia rebaudiana (Bert.) Bert.-Asteraceae, found on both leaf surfaces, originates from a single protruding, protodermal cell undergoing an anticlinal division. A subsequent series of periclinal divisions, occurring in acropetal sequence, leads to the formation of the trichome, composed of five pairs of cells, one pair of basal cells, another of stalk cells and three pairs of secretory head cells. Developing, still two-celled glandular trichomes already occur on leaf primordia of the second pair (these primordia measuring, in some cases, ca. 0.30 mm in length), and most of the glandular trichomes are at the mature phase on very young, expanding leaves, for example on those of the sixth pair. The secretory... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Stevia rebaudiana; Asteraceae; Glandular trichomes; Ontogeny; Histochemistry. |
Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042001000300013 |
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Registros recuperados: 82 | |
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