bluuebunny/crossref_metadata_2025_split huggingface dataset:
External morphology and abundance of antennal sensilla in australian gryllacrididae
Authors: Bland R. G. , Rentz D. C. F. 
Published: February 2005

AbstractThe long (49–93 mm) antennae of two species of Australian gryllacridids have high total numbers of sensilla consisting of five sensillar types. Ametrus sp. 7 has 22,300 (♀) and 26,250 (♂) sensilla; although the antennae of males are 33% longer than those of females, their sensillar density was 11% less. Bothriogryllacris pinguipes has 26,700 (♂) and 31,900 (♀) sensilla; antennae of females are 55% longer than those of males but sensillar density is 23% less. Aporous sensilla chaetica form 94.5 to 99.5% of all sensilla; they are presumably mechanoreceptors. Uniporous trichoid contact chemoreceptors range from 75–900 in number. Olfactory, multiporous, basiconic sensilla range from 22–440 and olfactory, coeloconic sensilla from 16–235. Two to five multiporous lenticular organs occur on all but female A. sp. 7. Differences in sensillar abundance between males and females are discussed as well as are the relationships between sensillar diversity on gryllacridid mouthparts and antennae. © 1994 Wiley‐Liss, Inc.
Development and growth of compound tooth plates in Callorhinchus milii (chondrichthyes, holocephali)
Authors: Didier D. A. , Stahl B. J. , Zangerl R. 
Published: February 2005

AbstractThe 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 members of a plesiomorphic chondrichthyan tooth family has been proposed, evidence for this hypothesis has been lacking. A new analysis of the development and structure of the tooth plates in Callorhinchus milii (Holocephali, Chimaeriformes) reveals the compound nature of the tooth plates in a chimaeroid fish. Each tooth plate consists of an oral and aboral territory that form independently in the embryo and maintain separate growth surfaces through life. The descending lamina on the aboral surface of the tooth plate demarcates the growth surface of the aboral territory. Comparison with the tooth plates of Chimaera monstrosa indicates that compound tooth plates may be a feature of all chimaeroids in which a descending lamina is present. The tooth plates in these fishes represent the fusion of two members of a reduced tooth family. The condition of the tooth plates in C. milii is plesiomorphic for chimaeroids and is of evolutionary significance in that it provides further evidence to support a lyodont dentition in chimaeroid fishes similar to that found in other chondrichthyans. © 1994 Wiley‐Liss, Inc.
Dolphin peripheral visual pathway in chronic unilateral ocular atrophy: Complete decussation apparent
Authors: Tarpley Raymond J. , Gelderd John B. , Bauserman Steven , Ridgway Sam H. 
Published: February 2005

AbstractComponents of the peripheral visual pathway were examined in two bottlenose dolphins, Tursiops truncatus, each with unilateral ocular degeneration and scarring of 3 or more years' duration. In both animals, the optic nerve associated with the blind eye right eye in Tg419 and left eye in Tt038 had a translucent, gel‐like appearance upon gross examination. This translucency was also evident in the optic tract contralateral to the affected eye. In Tg419, myelinated axons of varying diameters were apparent in the left optic nerve, whereas the right optic nerve, serving the blind eye, appeared to be devoid of axons. In Tt038, myelinated axons were associated with the right optic nerve (serving the functional eye) and left optic tract but were essentially absent in the left optic nerve and right optic tract. Examined by light microscopy in serial horizontal sections, the optic chiasm of Tt038 was arranged along its central plane in segregated, alternating pathways for the decussation of right and left optic nerve fibers. Ventral to this plane, the chiasm was comprised of fibers from the left optic nerve, whereas dorsal to the central plane, fibers derived from the right optic nerve. Because of this architectural arrangement, the right and left optic nerves grossly appeared to overlap as they crossed the optic chiasm with the right optic nerve coursing dorsally to the left optic nerve. At the light and electron microscopic levels, the optic nerves and tracts lacking axons were well vascularized and dominated by glial cell bodies and glial processes, an expression of the marked glial scarring associated with postinjury axonal degeneration. The apparent absence of axons in one of the optic tract pairs (right in Tt038 and left in Tg419) supports the concept of complete decussation of right and left optic nerve fibers at the optic chiasm in the bottlenose dolphin. © 1994 Wiley‐Liss, Inc.
Ultrastructure of the ileum epithelium ofMelipona quadrifasciata anthidioides(hymenoptera, apidae, meliponinae)
Authors: Da Cruz‐Landim Carminda 
Published: February 2005

AbstractStudy of the epithelial morphology of a stingless bee ileum from the pyloric valve to the last portion of high absorptive cells shows that although the bee ileum is an anatomically undifferentiated tube, four types of epithelial cells along the tube (in addition to the valve cells) indicate physiological differentiation. The anterior end seems to be less active in reabsorption, while the posterior region contains cells with typical morphology of an ion pump and permits conclusions about the mechanisms of absorption in the posterior end of the intestine. © 1994 Wiley‐Liss, Inc.
Allometry of cetacean forelimb bones
Authors: Dawson Susan D. 
Published: February 2005

AbstractThis study examines the allometric scaling relationships of the cetacean humerus, radius, and ulna. Bone lengths and diameters were measured for 20 species of odontocete and three species of mysticete cetaceans, representing eight of the nine extant cetacean families. The scaling of individual bone proportions (bone length vs. cranio‐caudal diameter, bone length vs. dorso‐ventral diameter), and of individual bone dimensions against estimated body mass, are compared to models of geometric and elastic similarity. The geometric similarity model describes the scaling relationship of bone length vs. cranio‐caudal diameter and body mass vs. cranio‐caudal diameter for the humerus only; geometric similarity also describes the scaling relationship of body mass vs. bone length for all three bones. None of the scaling relationships fits the elastic similarity model. The scaling relationships of bone length vs. dorso‐ventral diameter for all three bones, and bone length vs. cranio‐caudal diameter for the radius and ulna, exhibit negative allometry, indicating that large bones are less robust than small bones. Negative allometry of structural support elements has not been previously described for terrestrial mammals or plants. The high relative swimming speeds of small delphinids may generate sufficient stresses to require more robust bones relative to those of larger whales. © 1994 Wiley‐Liss, Inc.
Phylogenetic implications of structure of adult ovary and oogenesis in the penicillate diplopod, Eudigraphis nigricians (miyosi) (diplopoda: Myriapoda)
Authors: Yahata Kensuke , Makioka Toshiki 
Published: February 2005

AbstractWe describe some significant structures of the adult ovary in a Japanese penicillate diplopod, Eudigraphis nigricans, with respect to phylogenetic implications. The ovary is a long, saclike organ lying between the alimentary canal and the ventral nerve cord from the fourth through the ninth body segment. The ovarian wall consists of a thin ovarian epithelium and a sparse muscle covering. There are two types of oogenetic sites: a single, mound‐shaped germarium sitting on the center of the ventral ovarian epithelium, and ∼ 10 pairs of patchlike vitellarial areas metamerically arranged anterior and posterior to the germarium. The germarium consists of oogonia, early previtellogenic oocytes, and some somatic interstitial cells. In contrast, the vitellarial areas are composed of more advanced oocytes, follicle cells surrounding the oocytes, and some interstitial cells, but no oogonia. A few larger previtellogenic oocytes rise up from each vitellarial area into the ovarian lumen. Each of these oocytes is still connected with its own vitellarial area by a partial extension of its follicle. Vitellogenesis takes place in these oocytes rising in the ovarian lumen. The ripe primary oocytes leave their follicles to be transported forward into the oviducts. Some phylogenetic implications of the basic characteristics in ovarian structure and oogenesis of E. nigricans are discussed. © 1994 Wiley‐Liss, Inc.
Spermatogenesis in the urodele Amhystoma dumerilii
Authors: Uribe M. C. A. , Rios G. Gomez , Brandon R. A. 
Published: February 2005

AbstractThe male reproductive cycle of this paedomorphic species that occurs only in Lake Pátzcuaro, Michoacán, México, was investigated by documenting changes in germinal cells during the spermatogenic cycle. Cysts of germ cells divide synchronously to complete spermatogenesis during September through December, with the proportion of evacuated cysts or cysts containing spermatozoa increasing during this period. The chromatin changes during prophase I of meiosis reveal the usual leptotene, zygotene, pachytene, and diplotene stages. A basal body at the caudal end of the spermatozoan head connects to the flagellum. After spermiation, empty cysts contain a granular substance. Spermatogenesis in this species follows an annual cycle like other north temperate salamanders, rather than the continuous spermatogenesis of some tropical salamanders. © 1994 Wiley‐Liss, Inc.
Locomotor analysis of surface propulsion by three species of reduced‐limbed fossorial lizards (Lerista: Scincidae) from western australia
Authors: Gans Carl , Fusari Margaret 
Published: February 2005

AbstractThe relatively large, but superficially similar, Lerista macropisthopus, L. connivens, and L. lineopunctulata differ in bodily elongation and limb reduction, inhabit sandy areas, and move under sand. Visual analysis and computer‐generated excursion and curvature graphs show that each species moves differently on smooth and rough surfaces, on surfaces with and without nails, and in channels.The reduced‐limbed quadruped, Lerista macropisthopus walks frequently, using its four clawed limbs, whenever traction is available. Its undulating body curves uniformly but never generates slide‐pushing curves. The biped L. connivens walks with its hindlimbs, although less frequently, and/or oscillates its tail in propelling its relatively stiff, short body. The biped L. lineopunctulata rarely uses its hindlimbs but always undulates body and. tail. It can use single nails in cam‐follower progression. L. macropisthopus and L. connivens walk well in channels with rough bottoms, but only L lineopunctulata uses tunnel concertina to travel in channels with smooth bottoms.Friction of body surfaces dragged and of those transmitting propulsive forces is critical to these lizards and explains the division of movement into slow and rapid progression rates. Animals that have clawed limbs, no matter how reduced, use them. Body and tail generally are used differently. The tail may be flipped anteriorly to facilitate concertina. In nail arrays, travel is by simple, never by lateral, undulation. Apparently distinct motor coordination patterns are associated with differences in morphology, habit, and habitat. © 1994 Wiley‐Liss, Inc.
Development of astroglial cells in the encephalon of Gallotia galloti: A Golgi technique study
Authors: Romero‐Aleman M. Mar , Monzon‐Mayor Maximina , Plaza‐Perez M. Luz , Yanes Carmen 
Published: February 2005

AbstractSome variants of the Golgi techniques have been used to study the possible origin and developmental sequence of astroglial cells in the lizard Gallotia galloti. the developmental sequence consists of progressive transformations of astroglial cells originating either from radial glia or from glioblasts. The so‐called displaced radial glia, an intermediate cellular type between radial glia and astrocytes, indicate the radial glia/astrocytes transformation. Apparently, glioblasts also evolve into astroblasts that, in turn could develop into immature protoplasmic or fibrous astrocytes, precursors of mature protoplasmic and fibrous astrocytes, respectively. The present study confirms our previous ultrastructural and immunohistochemical studies on the same animal. © 1995 Wiley‐Liss, Inc.
Diversification of brain morphology in antarctic notothenioid fishes: Basic descriptions and ecological considerations
Authors: Eastman Joseph T. , Lannoo Michael J. 
Published: February 2005

AbstractThe Notothenioidei, a perciform suborder of 120 species, dominates the ichthyofauna of the Southern Ocean around Antarctica. Unlike most teleost groups, notothenioids have undergone a corresponding ecological and phyletic diversification and therefore provide an excellent opportunity to study the divergence of the nervous system in an unusual environment. Our goal is to evaluate notothenioid brain variation in light of this diversification. To provide a baseline morphology, we examine the gross morphology and histology of the brain ofTrematomus bernacchii, a generalized member of the family Nototheniidae. We then examine the variation in brain gross anatomy (32 species) and histology (10 species) of other notothenioids. Our sample represents about 27% of the species in this group and includes species from each of the six families, as well as species representing diverse ecologies. For comparison we reference the well‐studied brains of two species of temperate perciformes (Perca flavescensandLepomis humilis). Our results show that, in general, notothenioid brains are more similar to the brains of temperate perciforms than to the unusual brains of cave‐dwelling and deep‐sea fishes. Interspecific variation in gross brain morphology is comparable to that in Old World cyprinids and is illustrated for 17 species. Variation is especially noteworthy in the ecologically and geographically diverse family Nototheniidae. Measurements indicate that sensory regions (olfactory bulbs, eminentia granularis, and crista cerebellaris) exhibit the most pronounced variation in relative surface area. Association areas, including the corpus cerebelli and the telencephalon, exhibit moderate variation in size, shape, and lobation patterns. Regulatory areas of the brain, including the saccus vasculosus and the subependyma of the third ventricle, are also variable. These regions are best developed in species living in the subfreezing water close to the continent. In some species the expanded ependymal lining forms ventricular sacs, not previously described in any other vertebrate. Three species, including two nototheniids (Eleginops maclovinusandPleuragramma antarcticum) and the only artedidraconid in our sample, have distinctive brains. The unique brain morphology ofPleuragrammais probably related to a sensory (lateral line) specialization for feeding. Within the Nototheniidae, a phyletic effect on cerebellar morphology is evident in the Coriiceps group and in the Pleuragramminae. Neither phyletic position nor ecological factors (water temperature, position in the water column, dietary habits) alone fully expalin the pattern of notothenioid brain diversification. © 1995 Wiley‐Liss, Inc.
Skeletal morphogenesis in the urodele skull: I. Postembryonic development in the hemidactyliini (Amphibia: Plethodontidae)
Authors: Rose Christopher Stewart 
Published: February 2005

AbstractThe metamorphic species Eurycea bislineata is presented as a standard for evaluating the relationship between cranial ontogeny and life history in hemidactyliine plethodontid urodeles. Past and present descriptions are combined into a comprehensive summary of postembryonic skull development for this species, and the sequence, sizes of onset, and morphogenetic pathways are documented for all major remodelling events. Developmental series are also compared intraspecifically, between two populations of E. bislineata that differ in metamorphic size, and interspecifically, with species having different larval periods (Hemidactylium scutatum, Gyrinophilus porphyriticus, Pseudotriton ruber, E. wilderae, E. longicauda guttolineata) and with epigean (E. tynerensis, E. nana, and E. neotenes) and subterranean perennibranchiates (Haideotriton wallacei and Typhlomolge rathbuni). Cranial ontogeny is largely conserved in these hemidactyliines despite their disparate life histories. Outside the dichotomy of metamorphic and perennibranchiate development, variation is limited to interspecific differences involving the nasolacrimal duct, the repeated loss of the scleral cartilage, and minor dissociation of several metamorphic and postmetamorphic remodelling events. Some, but not all, of this variation is consistent with evolutionary differences in metamorphic size and age. The comparison of metamorphic and perennibranchiate hemidactyliines reveals a unique cranial ontogeny for urodeles, characterized by the abrupt and synchronous timing of almost all postembryonic remodelling, including the nasal skeleton, and the complete absence of these events in perennibranchiate forms. © 1995 Wiley‐Liss, Inc.
Morphology of complex lymphoepithelial organs of the anal canal (“anal tonsil”) in the bottlenose dolphin, Tursiops truncatus
Authors: Cowan Daniel F. , Smith Toby L. 
Published: February 2005

AbstractA complex of lymphoepithelial organs, the “anal tonsils,” is a consistent structure in the anal canal of the bottlenose dolphin, Tursiops truncatus. This complex occurs as a circumferential cluster of discrete tonsil like aggregations of lymphoid tissues, together with epithelial ducts (“crypts”) and occasional mucus secretory units in the extreme lower portion of the intestinal tract. These structures are concentrated in the segment lined by stratified squamous epithelium and extend for a variable distance cephalad from the anal aperture. The tonsils appear to be most active, judged by the amount of lymphoid tissue present, in young animals. Depletion of lymphocytes and cystic enlargement of the crypts, probably representing functional as well as morphological involution, is a consistent feature of older animals. © 1995 Wiley‐Liss, Inc.
Prenatal development of the integument in Delphinidae (Cetacea: Odontoceti)
Authors: Meyer Wilfried , Neurand Klaus , Klima Milan 
Published: February 2005

AbstractThe prenatal development of epidermis, dermis, and hypodermis was studied in embryos of different ago of two delphinid species (Stenella attenuata, Delphinus delphis), using light and transmission electron microscopical methods. The delphinid embryo is covered by a multilayered tissue formed by four different epidermal generations (periderm, stratum intermedium‐I, str. intermedium‐II, str. spinosum) produced by the str. basale. The first layer appears at about 40–50 mm of body length, the second type (s.i.‐I) about 60–160 mm, and the third type (s.i.‐II) is present at 160–500 mm. The first spinosal cells are produced at 225–260 mm body length; thenceforth, the epidermis increases continuously in thickness. Epidermal ridge formation begins about 400–mm body length. The development of the dermis is characterized by the early production of thin connective tissue fibers (40‐ 70‐mm body length) and simultaneously the cutaneuous muscle matures in structure. Vascular development intensifies between embryos of 150–225 mm, and collagen production increases markedly in fetuses of 225–260‐mm length. These events are paralledled by an increase in dermal thickness. The first elastic fibers can be recognized in the skin from the abdomen at about 600‐mm body length. The development of the hypodermis is marked by very rapid and constantly progressing growth, beginning about 60‐mm body length. The first typical fat cells appear in animals of 360–400 mm. Regional differences are obvious for all skin layers with regard to the flippers, where structural maturation proceeds more rapidly than in dorsal or abdominal regions. © 1995 Wiley‐Liss, Inc.
Design of the predatory legs of water bugs (Hemiptera: Nepidae, Naucoridae, Notonectidae, Gerridae)
Authors: Gorb Stanislav N. 
Published: February 2005

AbstractFunctional comparative morphology of predatory legs in five species of water bugs (Ilyocoris cimicoides, Nepa cinerea, Ranatra linearis, Notonecta glauca, and Gerris lacustris) has been investigatd adn the following peculiarities of leg design were revealed.
Subcoxal articulation may be monoaxial (G. lacustris, N. glauca), or, in contrast to walking leg type, biaxial (N. cinerea, R. linearis, I. cimicoides); the first axis is oriented along the coxa (torsion axis), the second one is perpendicular to the first (non‐torsion axis).
In contrast to walking leg type, which is characterized by cross suspension of the axis of coxal rotation in thoracal skeleton, this axis in G. lacustris is placed vertically. Non‐torsion coxal axis in R. linearis is oriented strongly transversal. This axis directs the leg strike forward.
Legs in the majority of species are planar: Torsion axes of the coxa, femur, and tibia are placed in the same plane. Axes of rotation of consequent joints in I. cimicoides are reciprocally sloped. Therefore, the end of the leg outlines the spiral trajectory, when all angles of joints are opening (closing). This is an adaptation for clinging to the stems of water plants.
Passive adduction of the femur in the trochanter‐femoral joint in N. glauca allows it to go around protuberances of the body wall, when the leg is sliding along them; recurrent femur movement during releasing from the obstacele is active due to the rt.fe muscle.
Only R. linearis has predatory legs, which permit the high‐speed pursuit of potential prey; other species realize this function using the swimming legs, whereas the forelegs are used for the manipulation movements.
Muscle arrangement in the prothorax of different species reflects both leg construction and constructional constraints of body design. Powerful flexor muscles (co1, co2, co3, co5, fl.ti, et.ti in R. linearis; fl.ta, fl.ti in N. glauca; fl.ti in I. cimicoides) have long tendons and short muscle bundles, which originate on the leg wall. As a result, the powerful force is developed along the muscle tendon.
Some features of the predatory leg are common for the species studies: elongation of coxae, thickening of femora, and increase of the degree of junction of tibia and tarsus. The muscles, which move the distal segment of the leg, are reinforced and the sclerite of the fl.ti tendon is enlarged. The joint angle of the distal segment is increased to 120°. © 1995 Wiley‐Liss, Inc.