Abstract:
:The different elements of the caudal skeleton of the South American catfish genera Nematogenys (Nematogenyinae) and Trichomycterus, Hatcheria, and Bullockia (Pygidiinae) (Siluriformes, Trichomycteridae) show Ontogenetic transformation of the second ural centrum in Trichomycteridae separates the subfamilies Nematogenyinae and Pygidiinae. In the former, the second ural centrum is aligned with the first ural centrum in early stages of ontogeny; it is not fused with the bases of hypurals 3 and 4 in any stage of development. In the Pygidiinae, in contrast, the second ural centrum is connected with the base of hypural 3 from an early stage of development on. One of the most noteworthy features of the Pygidiinae is the epural, a polymorphic element with three or four morphotypes that are species specific. The primitive catfish Nematogenys shows intraspecific variation in the ural centra, segmentation of procurrent caudal rays, and principal caudal ray formulae. Species of Trichomycterus, Hatcheria, and Bullockia are characterized by great intraspecific variability that involves ural centra, the epural, hypurapophyses, and the neural arches of the compound centrum. There is intraspecific variation in the fusion of the hypurals in some species of Trichomycterus. Intraspecific variation of the caudal skeleton of fishes of the family Trichomycteridae involves the presence and frequency of different morphotypes of the epural, neural arch of the compound centrum, fusion of hypurals, and principal caudal ray formulae. Ontogenetic changes of the first and second ural centra, hypurapophyses (with the exception of Nematogenys), and segmentation of procurrent caudal rays (in Nematogenys) are involved also.
journal_name
J Morpholjournal_title
Journal of morphologyauthors
Arratia Gdoi
10.1002/jmor.1051770208subject
Has Abstractpub_date
1983-08-01 00:00:00pages
213-229issue
2eissn
0362-2525issn
1097-4687journal_volume
177pub_type
杂志文章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::The neuromuscular control of the hind limb of helmeted guineafowl (Numida meleagris) locomoting on a treadmill at 1.0 m/sec was analyzed using simultaneous electromyography (EMG) and cineradiography. Activity from 16 heads representing 14 hip and knee muscles was recorded and correlated with limb movement and myologic...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199905)240:2<127::AID-JMOR
更新日期:1999-05-01 00:00:00
abstract::The functioning of the vertebrate eye depends on its absolute size, which is presumably adapted to specific needs. Eye size variation in lidless and spectacled colubrid snakes was investigated, including 839 specimens belonging to 49 genera, 66 species and subspecies. Variations of adult eye diameters (EDs) in both ab...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20028
更新日期:2012-08-01 00:00:00
abstract::The design of minimum-weight structures that retain their integrity under dynamic loading regimes has long challenged engineers. One solution to this problem found in both human and biological design is the optimization of weight and strength by hollowing a structure and replacing its inner core with supportive struts...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10302
更新日期:2006-10-01 00:00:00
abstract::Six locomotory muscles of wild common coots, Fulica atra, were analyzed histochemically. Capillarity and fiber-type distributions were correlated to the functional implications and physiological needs of each muscle. Leg muscles exhibit three unevenly distributed fiber types, a pattern that reflects the great variety ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199808)237:2<147::AID-JMOR
更新日期:1998-08-01 00:00:00
abstract::Embryos of goodeid fishes develop to term within the ovarian lumen, where they undergo considerable increase in weight due to transfer of maternal nutrients across a trophotaenial placenta. The placenta consists of an embryonic component, the trophotaeniae, and a maternal component, the ovarian lining. The latter was ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051840304
更新日期:1985-06-01 00:00:00
abstract::Adult female white-footed mice, Peromyscus leucopus, were exposed to long (LP) or short (SP) photoperiods for 6 weeks (experiment I). Another group of animals was kept for 6 weeks in SP, then injected SC with 30 micrograms prolactin twice daily for 2, 3, 4, or 6 days (experiment II). Ovaries from the mice in both expe...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051760211
更新日期:1983-05-01 00:00:00
abstract::Ultrastructure and deposition of the cuticles secreted by embryos representing eight insect orders were examined by transmission and scanning electron microscopy. Embryos of the apterygote silverfish Thermobia domestica deposit two embryonic cuticles. Deposition of the first (EC1) is initiated at the beginning of appe...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10338
更新日期:2005-06-01 00:00:00
abstract::Atretic follicles of the ovary of the Indian pied myna (Sturnus contra contra) were studied in birds collected each month throughout the year. Histological examination included histochemical techniques for 3β-hydroxy-steroid dehydrogenase (3β-HSDH) and for lipids. Atretic follicles were mainly of two types: nonburstin...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051900305
更新日期:1986-12-01 00:00:00
abstract::The appearance, cellular distribution, and changes of sugar residues during tooth development in adults of the polyphyodont, Liolaemus gravenhorsti, were investigated by using horseradish-peroxidase-conjugate lectins (lectin-HRP). With Con A (Canavalia ensiformis), the ameloblasts (late bell stage) show granular supra...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052220309
更新日期:1994-12-01 00:00:00
abstract::To elucidate the cellular mechanism underlying the growth of the peritoneal cover of the gut sinus and the heart in the polychaete Arenicola marina, cellular organization of these structures and proliferative potential of their cells were investigated using electron microscopy and electron microscopic autoradiography....
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10035
更新日期:2002-12-01 00:00:00
abstract::The morphology and probable evolution of the depressor muscles of the lower jaw, innervated by the seventh cranial nerve (VII;M. Ceratomandibularis, M. Depressor Mandibulae), in larval, neotenic, and metamorphosed Urodela were investigated. Observations on innervation and skeletal connections of the muscles were inclu...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199707)233:1<77::AID-JMOR7
更新日期:1997-07-01 00:00:00
abstract::The wall of the asymmetrical saclike lungs of the fishes Polypterus and Erpetoichthys consists of several functionally different tissue layers. Their lumen is lined by a surface epithelium composed of (1) highly attenuated cells, termed pneumocytes I; (2) pneumocytes II with lamellar bodies, presumably indicating surf...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052010206
更新日期:1989-08-01 00:00:00
abstract::Hind foot drumming is a form of seismic signaling that plays a vital role in the communication of several Bathyergidae species. Hind foot drumming is initiated by the rapid movement of the whole hind limb by flexion and extension of the hip and knee. This study aimed to determine if morphological adaptations of the hi...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.21110
更新日期:2020-04-01 00:00:00
abstract::We describe the complex shapes of myomeres and myosepta in the mackerels and tunas (Scombridae: Teleostei), and we reveal the orientation of two major systems of collagen fibers in myosepta and horizontal septa with respect to points of attachment to skeleton and skin. Our goal is to identify the likely pathways of th...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052170207
更新日期:1993-08-01 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::Sceloporus aeneus exhibits reproductive bimodality. That is, one taxon (Sceloporus aeneus bicanthalis) is viviparous whereas the other (Sceloporus aeneus aeneus) is oviparous. Morphological differences in luteal and oviductal structure were examined. Oviparous and viviparous females have distinct corpora lutea that fo...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051840109
更新日期:1985-04-01 00:00:00
abstract::Four species of Phocidae, or true seals, inhabit the waters surrounding the Antarctic continent. These animals are thought to have different diving capabilities. The Weddell seal, Leptonychotes weddelli, is known to be capable of attaining depths up to 600 meters. The respiratiory system of the Weddell seal shows the ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051470306
更新日期:1975-11-01 00:00:00
abstract::Tadpoles of several different genera were fed graded suspensions of uniform polystyrene particles to determine the lower size limit of particles that could be ingested. Certain tadpoles can extract suspended particles as small as 0.126 μ in diameter from the water. In terms of particle size, this is an efficiency comp...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051370303
更新日期:1972-07-01 00:00:00
abstract::We investigated growth-related and sex-related morphological changes in the skulls of 144 North Pacific common minke whales Balaenoptera acutorostrata. Measurement was conducted at 39 points on the skull and mandible to extract individual allometric equations relating the length and zygomatic width of the skull. The r...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20288
更新日期:2014-10-01 00:00:00
abstract::The uptake and retention of radiolabeled estradiol by both the male and female reproductive organs were examined in the baboon. Two male and two female baboons were injected intracardially with 1 microgram/kg body weight of 3H-estradiol and two animals, one male and one female, were injected with both labeled and 100 ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051720203
更新日期:1982-05-01 00:00:00
abstract::A reduction in free ribosomes and increases in rough endoplasmic reticulum and Golgi complexes in follicle cells during oogenesis suggest their involvement in supplying precursor material for synthesis of the vitelline and chorionic membranes of the ichneumonid parasitoid Campoletis sonorensis. The inner region of the...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051740207
更新日期:1982-11-01 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::The three-dimensional structure of the organ of Bellonci in the marine amphipod Gammarus setosus and the relationship between its sensory cells and concretion are described using light, transmission, and scanning electron microscopy, with chemical treatment for cell lysis, calcium chelation, glycogen staining, and lan...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051810109
更新日期:1984-07-01 00:00:00
abstract::Homolid crabs (Hypsophrys) from water deeper than 700 m in the Straits of Florida and Arabian Sea have smooth darkened oval spots contrasting with the surrounding roughened integument on inner and outer surfaces of each pincer at the base of the fixed finger. Cuticle is thinner over these spots than over surrounaing t...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051500407
更新日期:1976-12-01 00:00:00
abstract::The feline anterior sartorius is a long strap-like muscle composed of short muscle fibers. Nerve branches that enter this muscle contain the axons of motor units whose constituent muscle fibers are distributed asymmetrically within the muscle. In the present study, twitch and tetanic isometric contractions were evoked...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052130204
更新日期:1992-08-01 00:00:00
abstract::Cetacean middle ears are unique among mammals in that they have an elongated tympanic membrane, a greatly reduced manubrium mallei, and an incudal crus longum that is shorter than the crus breve. Elongation of the tympanic membrane and reduction of the manubrium is thought to be related to an evolutionary rotation of ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1044
更新日期:2001-08-01 00:00:00
abstract::Descriptions are provided of the histology and ultrastructure of the male internal reproductive tracts from three species of Camponotus, representing three subgenera. This study is the first to provide ultrastructural information on the testes (including spermatogenesis and spermiogenesis), seminal vesicles, and acces...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052110308
更新日期:1992-03-01 00:00:00
abstract::We studied early neurulation events in vitro by transplanting quail Hensen's node, central prenodal regions (before the nodus as such develops), or upper layer parts of it on the not yet definitively committed upper layer of chicken anti-sickle regions (of unincubated blastoderms), eventually associated with central b...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10436
更新日期:2006-07-01 00:00:00
abstract::Standard transmission electron microscopy (TEM) techniques have been applied to three species of phoronids to describe cytological features of their nervous systems. Four types of neurons have been distinguished by morphological and ultrastructural criteria, mainly involving their kinds of vesicles. Glial cells with c...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199612)230:3<265::AID-JMOR
更新日期:1996-12-01 00:00:00