Clasper gland morphology and development in Potamotrygon magdalenae (Elasmobranchii: Potamotrygonidae).

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

authors： Blackburn DG,Lestz L,Barnes MS,Powers KG,Langkilde T

更新日期：2018-11-01 00:00:00

abstract：:The paired Y-organs of crustaceans control the molting process. In males of C. antennarius, these glands are opalescent, lobulated, epithelioid structures embedded in brown fatty tissue. Cells in the periphery extend processes to the connective tissue capsule, an arrangement that suggests increased surface area for me...

journal_title：Journal of morphology

authors： Hinsch GW,Spaziani E,Vensel WH

更新日期：1980-02-01 00:00:00

abstract：:The ultrastructure of a well studied insect chemosensory unit is presented in this report. Two separate lumina are present in this chemosensory unit, the trichogen and sensillar lumina. The fluid within the trichogen lumen exclusively bathes the dendritic terminals, and may be involved with the reception and/or modula...

journal_title：Journal of morphology

authors： Felt BT,Vande Berg JS

更新日期：1976-11-01 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

authors： Yorisue T,Chan BK,Kado R,Watanabe H,Inoue K,Kojima S,Høeg JT

更新日期：2016-05-01 00:00:00

abstract：:Vibrissae or follicle-sinus complexes (F-SCs) are highly developed mammalian sensory structures. These blood-filled sinuses are richly innervated and possess novel mechanoreceptors. Although much is known regarding the function of F-SCs in terrestrial mammals, much less is known regarding marine carnivores such as pin...

journal_title：Journal of morphology

authors： Sprowls CD,Marshall CD

更新日期：2019-11-01 00:00:00

abstract：:Non-innervated macrotrichia and microtrichia, thick-walled chemoreceptors and three kinds of thin-walled chemoreceptors are present on the antennal flagellum of Frenesia missa. One of the thin-walled receptors, the plate organ, is of a type not previously recorded for any insect. About four times as many plate organs ...

journal_title：Journal of morphology

authors： Slifer EH,Sekhon SS

更新日期：1971-11-01 00:00:00

abstract：:Slender blindsnakes (Leptotyphlopidae) are known to use a unique feeding mechanism that involves rapid flexions of the tooth-bearing lower jaw. However, the morphology of the leptotyphlopid jaw apparatus has remained poorly studied due to the extremely small size of these snakes. Here I present a detailed description ...

journal_title：Journal of morphology

authors： Kley NJ

更新日期：2006-04-01 00:00:00

abstract：:Many studies in the genus Poecilia have focused on reproductive and genetic characteristics of Poecilia formosa, the Amazon molly, and its sympatric species P. latipinna and P. mexicana. The research literature of Poecilia dentition has been limited to general tooth morphology. Essentially absent are comparative analy...

journal_title：Journal of morphology

authors： Lewis SR,Rasch EM,Hossler FE,Kalbfleisch JH,Monaco PJ

更新日期：1999-03-01 00:00:00

abstract：:This study describes the male reproductive cycle of Sibynomorphus mikanii from southeastern Brazil considering macroscopic and microscopic variables. Spermatogenesis occurs during spring-summer (September-December) and spermiogenesis or maturation occurs in summer (December-February). The length and width of the kidne...

journal_title：Journal of morphology

authors： Rojas CA,Barros VA,Almeida-Santos SM

更新日期：2013-02-01 00:00:00

abstract：:The fine structure of the shell and underlying mantle in young juveniles of the articulate brachiopod Terebratalia transversa has been examined by electron microscopy. The first shell produced by the mantle consists of a nonhinged protegulum that lacks concentric growth lines. The protegulum is secreted within a day a...

journal_title：Journal of morphology

authors： Stricker SA,Reed CG

更新日期：1985-03-01 00:00:00

abstract：:Timed-sequence studies have shown that reticulate scales on the ventral footpads of birds do not undergo "epidermal placode" formation during their morphogenesis, but arise as symmetrical evaluations similar to the scales of snakes and lizards. Unlike the scutellate scales on the dorsal surface of the foot, in which t...

journal_title：Journal of morphology

authors： Sawyer RH,Craig KF

更新日期：1977-10-01 00:00:00

abstract：:We investigated muscle development in the Japanese flounder Paralichthys olivaceus, focusing primarily on the cranial muscles, using a whole mount immunohistochemical staining method. It is well established that during the very early stages of morphogenesis, until 4 days post hatching (dph), muscles required for feedi...

journal_title：Journal of morphology

authors： Uji S,Kurokawa T,Suzuki T

更新日期：2010-07-01 00:00:00

abstract：:There are remarkable interspecific differences in the sizes of the larvae of Andean frogs of the genus Telmatobius. This size variation seems to be associated with the duration of the larval stage and may affect the hind-limb morphology in Telmatobius. Larval, juvenile, and adult Telmatobius rubigo and T. oxycephalus ...

journal_title：Journal of morphology

authors： Barrionuevo JS

更新日期：2020-12-01 00:00:00

abstract：:Changes in size frequency distribution of extrastromal follicles, atretric follicles (AF), and the number of oogonia, oocytes, and primordial follicles in the ovaries are studied in Calotes versicolor during its annual reproductive cycle. Extrastromal follicles were graded into stages I to VI based on their diemeter. ...

journal_title：Journal of morphology

authors： Shanbhag BA,Prasad BSK

更新日期：1993-04-01 00:00:00

abstract：:It has been hypothesized that fluctuating asymmetry (FA) may provide an indication of the functional importance of structures within an organism, with structures that more strongly impact fitness being more symmetric. Based on this idea, we predicted that for tetrapods in which the forelimbs and hindlimbs play an uneq...

journal_title：Journal of morphology

authors： Didde RD,Rivera G

更新日期：2019-04-01 00:00:00

abstract：:The form of amniote claws has been extensively investigated, often with inferences about ecological association being drawn from studies of their geometry. Various methods have been used to quantify differences in the geometry of claws, but rarely have the underlying assumptions of such methods been addressed. Here, w...

journal_title：Journal of morphology

authors： Tinius A,Patrick Russell A

更新日期：2017-02-01 00:00:00

abstract：:The correlation between skin structure and hydrodynamic design of the dorsal fin of the harbor porpoise (Phocoena phocoena) was examined. For the study of fin morphology and geometry, a scheme of sampling representing a two-parameter mesh on the fin surface was used. At each data point the thickness of the epidermis, ...

journal_title：Journal of morphology

authors： Pavlov VV

更新日期：2003-12-01 00:00:00

abstract：:In the Mexican axolotl (Ambystoma mexicanum), the pronephros begins to form at the four-somite stage. It is initially continuous with the posterior-lateral region of somite 2 and the lateral margin of somites 3 and 4. By the seven-somite stage, the pronephros has become compacted, and the cells are now morphologically...

journal_title：Journal of morphology

authors： Gillespie LL,Armstrong JB

更新日期：1985-08-01 00:00:00

abstract：:Studies on birds have led to the hypothesis that increased intestinal absorption between enterocytes (paracellular) evolved as a compensation for smaller intestinal size in fliers, which was perhaps selected to minimize the mass of digesta carried. This hypothesis predicts that bats will also exhibit relatively reduce...

journal_title：Journal of morphology

authors： Zhang ZQ,Brun A,Price ER,Cruz-Neto AP,Karasov WH,Caviedes-Vidal E

更新日期：2015-01-01 00:00:00

abstract：:Two different patterns of wing venation are currently supposed to be present in each of the three orders of Paraneoptera. This is unlikely compared with the situation in other insects where only one pattern exists per order. We propose for all Paraneoptera a new and unique interpretation of wing venation pattern, assu...

journal_title：Journal of morphology

authors： Nel A,Prokop J,Nel P,Grandcolas P,Huang DY,Roques P,Guilbert E,Dostál O,Szwedo J

更新日期：2012-05-01 00:00:00

abstract：:Body length is one of the most important factors that influence organismal function and ecological niche. Although larger animals tend to have a suite of physiological advantages, such as lower mass-specific metabolic rates and lower costs of transport, they may also experience significant limitations to unsteady loco...

journal_title：Journal of morphology

authors： Kahane-Rapport SR,Goldbogen JA

更新日期：2018-09-01 00:00:00

abstract：:The extracellular matrices (ECMs) surrounding the benthic embryos and larvae of the seastar Patiriella exigua and the planktonic embryos of Patiriella regularis were examined by transmission and scanning electron microscopy. Three ECMs surround unhatched embryos: An outer jelly coat, a fertilization envelope, and an i...

journal_title：Journal of morphology

authors： Cerra A,Byrne M

更新日期：1995-07-01 00:00:00

abstract：:Scanning electron microscopy reveals that the flat tongue of Platemys pallidipectoris has shallow grooves and no lingual papillae. The surface of the tongue is covered with dome-shaped bulges, each corresponding to a single cell. Short microvilli are distributed over the cell surface. Light microscopy shows a stratifi...

journal_title：Journal of morphology

authors： Beisser CJ,Weisgram J,Splechtna H

更新日期：1995-12-01 00:00:00

abstract：:Profiles with all orientations have been used to visualize the 3D structure of ivory from tusks of elephant, mammoth, walrus, hippopotamus, pig (bush, boar, and warthog), sperm whale, killer whale, and narwhal. Polished, forming, fractured, aged, and stained surfaces were prepared for microscopy using epi-illumination...

journal_title：Journal of morphology

authors： Locke M

更新日期：2008-04-01 00:00:00

abstract：:Andean frogs of the genus Telmatobius occur at high elevations, they have an aquatic mode of life and large tadpoles. There are more than 60 species that closely resemble one another and have low values of genetic divergence. However, the skeleton, particularly the cranium, is interspecifically variable with respect t...

journal_title：Journal of morphology

authors： Barrionuevo JS

更新日期：2018-09-01 00:00:00

abstract：:The enteric nervous system consists of a number of interconnected networks of neuronal cell bodies and fibers as well as satellite cells, the enteric glia. Basic fibroblast growth factor (bFGF) is a mitogen for a variety of mesodermal and neuroectodermal-derived cells and its presence has been described in many tissue...

journal_title：Journal of morphology

authors： Chadi G,Gomide VC,Rodrigues de Souza R,Scabello RT,Maurício da Silva C

更新日期：2004-09-01 00:00:00

abstract：:The larval epithelium of the sea urchin, Lytechinus pictus, consists of squamous cells and bands of columnar epithelial cells bearing cilia. During metamorphosis this tissue undergoes a series of rapid, complex changes. Through the scanning and transmission electron microscope, we describe and analyse these changes. T...

journal_title：Journal of morphology

authors： Cameron RA,Hinegardner RT

更新日期：1978-07-01 00:00:00

abstract：:Serial sections were used to map the ventrally positioned neurons of the anterior nerve cord of a 12.5-day amphioxus larva from the infundibular region to the end of somite 2. Synaptic patterns reveal five categories of descending pathways, four of which are associated with the ventral compartment (VC) motoneurons res...

journal_title：Journal of morphology

authors： Lacalli TC,Kelly SJ

更新日期：2003-08-01 00:00:00

abstract：:We have studied the gill epithelium of Oreochromis niloticus using transmission electron microscopy with the particular interested relationship between cell morphology and osmotic, immunoregulatory, or other non-regulatory functions of the gill. Pavement cells covered the filament epithelium and lamellae of gills, wit...

journal_title：Journal of morphology

authors： Monteiro SM,Oliveira E,Fontaínhas-Fernandes A,Sousa M

更新日期：2010-05-01 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

authors： Schwaha T,Handschuh S,Redl E,Walzl MG

更新日期：2011-03-01 00:00:00