Abstract:
:For the first time the scanning electron microscope was used to compare developmental changes in scorpion embryos and the first and second stadia. In the buthid species of this study, Centruroides vittatus, and all other scorpions, the newborn climb up on their mother's back and remain there without feeding for several days. At this location, they undergo their first molt and in a few days they disperse, fully capable of foraging in the terrestrial environment. The results here support earlier suggestions that the first stadium (pronymph) is a continuation and extension of embryological development. The first molt results in a nymph with exoskeletal features much like those in the adult. In the first molt the metasoma becomes relatively longer, and the sting (aculeus) becomes sharp and functional. The metasomal segments are modified for dorsal flexion and sting use. The embryos and the pronymphs have spiracles that open into an invagination near the posterior margin of flap-like abdominal plates in segments 4-7 of the ventral mesosoma. The second instars have spiracles that lead to book lungs farther anterior in sternites. Tubular legs with cylindrical segments in embryos and pronymphs become more sculptured and oval in the transverse plane. Each leg in the pronymph has a blunt, cup-shaped tip while distal claws (ungues, dactyl) are present in the second instar and subsequent stages. There are some sharp bristles and primordial sensilla in the pronymphs, but the second stadium has adult-like surface features: rows of knobs or granulations (carinae), serrations on the inner surfaces of cheliceral and pedipalpal claws, filtering hairs at the mouthparts, peg sensilla on the pectines, and mechano- and chemoreceptor sensilla on the body and appendages. Scorpion embryos and pronymphs have some structures like fossil scorpions thought to have been aquatic. There is a gradual development of features that appear to be terrestrial adaptations. Evidence is provided for the formation of the sternum from third and fourth leg coxal primordia and possibly from the first abdominal segment. This study is the first to provide evidence for a forward shift of the gonopore along with other structures in the anterior abdomen.
journal_name
J Morpholjournal_title
Journal of morphologyauthors
Farley RDdoi
10.1002/jmor.10227keywords:
subject
Has Abstractpub_date
2005-07-01 00:00:00pages
1-27issue
1eissn
0362-2525issn
1097-4687journal_volume
265pub_type
杂志文章abstract::Scleractinian corals begin their biomineralization process shortly after larval settlement with the formation of calcium carbonate (CaCO(3)) structures at the interface between the larval tissues and the substrate. The newly settled larvae exert variable degrees of control over this skeleton formation, providing an op...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20401
更新日期:2015-10-01 00:00:00
abstract::A chromatolysis study, 14 to 21 days following denervation, showed the spinal cord representation of the nerve to the posterior latissimus dorsi muscle to be in the ventrolateral cell column between cervical ganglia 14 and 15. to characterize cevical neruos nt undergoing chromatolysis, histochemical stuies were done t...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051470204
更新日期:1975-10-01 00:00:00
abstract::The Norway lobster (Nephrops norvegicus) is economically important in Europe. However, apart from the female reproductive system, very little is known about its internal anatomy. This article focuses on studying the internal anatomy and ultrastructure of the male reproductive system. This system follows the general pa...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20002
更新日期:2012-06-01 00:00:00
abstract::The spleen of sea bass (Dicentrarchus labrax) is composed mainly of red pulp, whereas the white pulp is poorly developed. The red pulp consists of clear reticular cells intermingled with blood cells, sinusoids, and melanomacrophage centers (MMCs). The MMCs are enclosed by an interrupted connective tissue capsule and s...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052060304
更新日期:1990-12-01 00:00:00
abstract::The ovarian follicles of Ctenosaura pectinata exhibit a clear seasonal cycle in morphology. Early in development, each oocyte is surrounded by a granulosa composed of a single layer of cuboidal or squamous cells and thin thecal layers. As folliculogenesis progresses, the granulosa becomes multilayered and composed of ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199610)230:1<99::AID-JMOR8
更新日期:1996-10-01 00:00:00
abstract::The cellular populations present in dorsomedial cortex in the snakes Constrictor constrictor, Natrix sipendon and Thamnophis sirtalis are described at the light microscopic level using Nissl and Golgi preparations as well as at the ultrastructural level. This area plays a central role in cortical organization in snake...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051610207
更新日期:1979-08-01 00:00:00
abstract::The phylogenetic position of bryozoans has been disputed for decades, and molecular phylogenetic analyzes have not unequivocally clarified their position within the Bilateria. As probably the most basal bryozoans, Phylactolaemata is the most promising taxon for large-scale phylogenetic comparisons. These comparisons r...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10915
更新日期:2011-03-01 00:00:00
abstract::Acipenseriformes (sturgeon and paddlefish) are basal actinopterygians with a highly derived cranial morphology that is characterized by an anatomical independence of the jaws from the neurocranium. We examined the morphological and kinematic basis of prey capture in the Acipenseriform fish Scaphirhynchus albus, the pa...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10095
更新日期:2003-06-01 00:00:00
abstract::This investigation describes the morphogenesis of the type I pneumocyte from the neonatal stage to the age of 3 months. Cells lining subpleural air spaces were photographed from electron microscopic serial sections and a three-dimensional representation of each cell was obtained by transferring the contours of the cel...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051820205
更新日期:1984-11-01 00:00:00
abstract::Prey capture in Agama stellio was recorded by high-speed video in combination with the electrical activity of both jaw and hyolingual muscles. Quantification of kinematics and muscle activity patterns facilitated their correlation during kinematic phases. Changes in angular velocity of the gape let the strike be subdi...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052240306
更新日期:1995-06-01 00:00:00
abstract::Morphologists and systematists have long suspected that dietary consistency can affect skull and dental form in mammals. We examined plasticity of skull shape and tooth morphology in prairie deer mice (Peromyscus maniculatus bairdii) by feeding mice diets that differed in consistency but not nutritional quality. Shape...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199608)229:2<229::AID-JMOR
更新日期:1996-08-01 00:00:00
abstract::All extant members of Phocoenidae (porpoises) have been characterized as pedomorphic based on skeletal characters. To investigate the ontogenetic background for pedomorphosis and assess interspecific differences in ontogeny among phocoenids, samples of the six extant species were compared in terms of development of bo...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10900
更新日期:2011-02-01 00:00:00
abstract::An otolith increment is composed of an incremental zone and a discontinous zone. Observation of the otoliths of Oreochromis niloticus with transmission and scanning electron microscopy reveals that organic fibers are concentrated in the discontinuous zone and are relatively scarce in the incremental zone. On the other...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052110210
更新日期:1992-02-01 00:00:00
abstract::This work is concerned with the ultrastructural organization and some histochemical features of the vacuolar cells of the demosponge Oscarella lobularis. Vacuolar cells are characterized by large clear vacuoles containing an aqueous fluid. They are commonly found in the mesohyl of this sponge and tend to constitute a ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051880104
更新日期:1986-04-01 00:00:00
abstract::I focus on the crucial links between the discovery of nonhuman primates by Westerners, discussions on our place in nature, the chain of being, racism, and the history of primate comparative anatomy and of so-called "anatomical human racial studies." Strikingly, for more than a millennium humans knew more about the int...
journal_title:Journal of morphology
pub_type: 杂志文章,评审
doi:10.1002/jmor.20783
更新日期:2018-04-01 00:00:00
abstract::Barnacle cypris larvae show high morphological variation in the organs used in search of and attaching to a substratum. This variation may represent adaptation to the habitat of the species. Here, we studied SEM level morphologies of cypris antennular sensory and attachment organs in a deep-sea vent endemic species (N...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20522
更新日期:2016-05-01 00:00:00
abstract::Astroblepidae or "climbing catfishes" encompass a single genus of species living in high altitude rivers in the Andes of South America. They are characterized by a specialized head morphology closely resembling their better known, widely radiated sister family Loricariidae, or armored suckermouth catfishes. Existent d...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20169
更新日期:2013-10-01 00:00:00
abstract::Over the past few decades, geometric morphometric methods have become increasingly popular and powerful tools to describe morphological data while over the same period artificial neural networks have had a similar rise in the classification of specimens to preconceived groups. However, there has been little research i...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20626
更新日期:2017-01-01 00:00:00
abstract::New schemata of the liver are presented to discuss the combination of the three kinds of liver lobules known until today in a chalk-talk-manner. Terminology is also discussed. Further investigations are needed involving the construction and the vascular pattern of compound lobules of the three individial lobules of th...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051620204
更新日期:1979-11-01 00:00:00
abstract::During ontogeny, the apical and basal components of dicamptodontid teeth exhibit three major developmental stages: nonpedicellate, subpedicellate, and pedicellate. Premetamorphic larvae tend to have nonpedicellate teeth, incompletely or recently metamorphosed individuals tend to have subpedicellate teeth, and fully tr...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051990204
更新日期:1989-02-01 00:00:00
abstract::Ventral bars, cartilaginous projections from the ventral aspect of the synsacrum that contact and form a joint with the ilium, were found in all normal chick embryos of age E9 and older. Bars were absent in a number of embryos which had been paralyzed from age E4 by the use of the acetylcholine receptor blocker alpha-...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051730205
更新日期:1982-08-01 00:00:00
abstract::Features of embryonic development in birds traditionally have been assumed to be shared by sauropsids in general. Herein, we document a pattern of yolk processing and cellularization in the Eastern fence lizard (Sceloporus undulatus) that is fundamentally different from that of birds. In the avian pattern, cells of th...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20892
更新日期:2018-11-01 00:00:00
abstract::The pattern of onset and general rate of cranial ossification are compared in two marsupials, Monodelphis domestica (Didelphidae) and Macropus eugenii (Macropodidae). In both species a similar suite of bones is present at birth, specifically those surrounding the oral cavity and the exoccipital, and in both postnatal ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052150203
更新日期:1993-02-01 00:00:00
abstract::Newly metamorphosed Kenyan reed frogs, Hyperolius viridiflavus ferniquei, are able to regenerate amputated digits. The terminal digital pad is also completely reformed. Differentiation of the regenerating digital pad was studied by scanning electron microscopy. External differentiation of the digital pad began late in...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051530305
更新日期:1977-09-01 00:00:00
abstract::Anseriform birds were surveyed to examine how the degree of postcranial pneumaticity varies in a behaviorally and size-diverse clade of living birds. This study attempts to extricate the relative effects of phylogeny, body size, and behavioral specializations (e.g., diving, soaring) that have been postulated to influe...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10190
更新日期:2004-08-01 00:00:00
abstract::The abdominal cerci of the wood cricket, Nemobius sylvestris, are covered by a variety of hair-like sensilla that differ in length, thickness, and articulation. Fillings from the cercal nerves with cobalt chloride and fluorescent dyes revealed the projection of sensory axons into the terminal abdominal ganglion of the...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10672
更新日期:2008-12-01 00:00:00
abstract::The chimaeroid holocephalian fishes are distinguished among extant chondrichthyans by the possession of three pairs of tooth plates, evergrowing and partially hypermineralized, that are not shed and replaced like the teeth of living elasmobranchs. Although derivation of the chimaeroid tooth plate from the fusion of me...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052220108
更新日期:1994-10-01 00:00:00
abstract::The evolution of viviparity alters the physical relationship between mothers and offspring and the prevalence of viviparity among squamate reptiles presents an opportunity to uncover patterns in the evolution of placental structure. Understanding the breadth of this diversity is limited because studies of placental st...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20912
更新日期:2019-01-01 00:00:00
abstract::Using immunocytochemistry at light- and electron-microscope levels, we studied the distribution of three monoclonal antibodies (AE1, AE2, AE3) specific for mammalian alpha-keratins in regenerating lizard epidermis. We also characterized the keratins expressed during this process by immunoblotting after electrophoretic...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/1097-4687(200012)246:3<179::AID-JMOR2>3.0.
更新日期:2000-12-01 00:00:00
abstract::The allometric relations of diameter and length of humerus, ulna, femur, and tibia of 108 specimens, from 63 different breeds of dogs and 12 specimens of wolves, were calculated by means of model II of regression or major axis method. Only for the tibia were the values of wolves included in the cluster formed for dog ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051900107
更新日期:1986-10-01 00:00:00