External Morphology

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The possible contribution of pituitary hormones to the heterochronic development of gonads and external morphology in overwintered larvae of Hynobius retardatus

The possible contribution of pituitary hormones to the heterochronic development of gonads and external morphology in overwintered larvae of Hynobius retardatus

ABSTRACT In Hynobius retardatus, most larvae in regions of low elevation metamorphose by autumn of the same year. However, larvae of some populations found in cold, mountainous ponds cannot metamorphose within the year and become aged, overwintered larvae. Gonadal develop- ment in larvae under the age of 1 year (larvae developed from eggs spawned in the same year) and in aged, overwintered larvae (spawned and hatched in previous years) was examined at the same developmental stage (stage 63, full-grown larval stage). The number of germ cells and the cross- sectional areas of the gonads were much larger in 2-season-overwintered (third year) larvae than in larvae under the age of 1 year. To obtain reliable probes for investigating the possible contribution of TSH, FSH and LH to metamorphosis and gonadal development, cDNAs for Hynobius TSH β , FSH β and LHβ genes were cloned. Their expressions were analyzed by means of semi-quantitative RT- PCR in larvae under the age of 1 year and in 2-season-overwintered larvae. No differences were observed in expression levels of either TSHβ or LHβ between larvae under the age of 1 year and the overwintered larvae. In contrast, expression of FSHβ was much higher in the overwintered larvae than in larvae under the age of 1 year. These results suggest that gonadal development proceeds gradually with age even in the overwintered larvae, but that metamorphosis is retarded, probably due to the larvae’s cold habitat. Heterochronic development of gonads and external morphology has been demonstrated in H. retardatus, suggesting a potency for neotenic reproduction in this species.

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The external morphology of eggs of three Rhopalidae species (Hemiptera: Heteroptera) with a review of the eggs of this family

The external morphology of eggs of three Rhopalidae species (Hemiptera: Heteroptera) with a review of the eggs of this family

Abstract. The external morphology of eggs and manner of oviposition of three rhopalid species, Brachycarenus tigrinus (Schilling, 1829), Chorosoma schillingi (Schilling, 1829) and Rhopalus (Aeschyntelus) maculatus (Fieber, 1837) are described. The eggs were studied using Scanning Electron Microscopy (SEM), and the results complete previous observations.The emphasis of the study is on the characteristics of eggs and details of oviposition in representatives of the family Rhopalidae. The chorionic origin of attachment stalk was confi rmed only in the Chorosomatini. A completely smooth egg chorion was recognized in R. (A.) maculatus, as a unique condition within at least the Pentatomomorpha.

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External morphology of the cycliophoran dwarf male: a comparative study of Symbion pandora and S. americanus

External morphology of the cycliophoran dwarf male: a comparative study of Symbion pandora and S. americanus

The cycliophoran dwarf male has already been descri- bed using light and transmission electron microscopy, and at the cytochemical level using confocal laser scanning microscopy (Funch and Kristensen 1997; Obst and Funch 2003; Neves et al. 2009a, b, 2010). However, only one male of Symbion pandora has so far been described by scanning electron microscopy, and its external morphology was apparently altered during the freeze-drying technique used to prepare specimens (cf. Obst and Funch 2003). Also, the high loss of specimens during preparation, due to the minute size of the males, limited the success of this approach. In the study presented herein, we compare the external morphology of the dwarf males of S. pandora and S. americanus.

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Scanning the Hyocephalidae: details of their external morphology with respect to phylogenetic relationships within Eutrichophora (Hemiptera: Heteroptera)*

Scanning the Hyocephalidae: details of their external morphology with respect to phylogenetic relationships within Eutrichophora (Hemiptera: Heteroptera)*

Abstract. Hyocephalidae (Hemiptera: Heteroptera: Pentatomomorpha) is a small family of true bugs containing two genera and three species endemic to Australia. For the fi rst time, we examine here selected structures of their external morphology using scanning electron microscopy – the external structures associated with the metathoracic and dorsoabdominal scent glands, the strainer organ on the sternite III, as well as the trichobothrial pattern and ultrastructure. The following character states are confi rmed (i, ii, iii) or newly recognised (iv, v) as autapomorphies of Hyo- cephalidae: i) apically projected scimitar-shaped peritreme of the metathoracic scent glands; ii) presence of a strainer organ on sternite III in both sexes; iii) trichobothria on sternite V placed immediately ventrad of spiracle, iv) trichobothria on each of abdominal segments III–VII all grouped together within a common trichome, and v) presence of crocus-like structures within the trichome. Of particular interest is the presence of a shallow open bothrium (type B) surrounded by a trichome in Hyocephalidae, a probably derived character state shared with Pyrrhocoroidea and most Lygaeoidea, while Stenocephalidae (previously considered to be closely related to Hyocephalidae and used here for comparison) and the remaining Coreoidea possess a recessed bothrium of type A2, lacking the trichome. The morphology of trichobothria in Hyocephalidae may thus suggest either their closer relationship to Lygaeoidea + Pyrrhocoroidea than to Co- reoidea, or a parallel evolution of the open bothrium with trichome in Eutrichophora. We highlight the importance of Hyocephalidae for a better understanding of the phylogeny of Eutrichophora and the urgent need to obtain phylogenomic data for future research. A taxonomic catalogue of Hyocephalidae is supplemented. The neotype designation for Hyocephalus aprugnus Bergroth, 1906 made by Š TYS (1964) and supported by G RANT & Š TYS (1970) is found invalid.

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External Morphology and Weight - Length Relationships (WLRs) of Harbour Porpoise, Phocoena phocoena (Cetacea: Phocoenidae) in the Black Sea

External Morphology and Weight - Length Relationships (WLRs) of Harbour Porpoise, Phocoena phocoena (Cetacea: Phocoenidae) in the Black Sea

Studies on the harbour porpoise with respect to sexual variation in morphometric characteristics and weight-length relationships are scarce in the Black Sea. The present study summarizes information on the external morphology and the WLRs of pregnant and non-pregnant females and males of harbour porpoise; Phocoena phocoena obtained as bycatch in the turbot gill net fisheries along the Rize coast in the Black Sea.

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A functional morphological approach to the scaling of the feeding system
in the African catfish, Clarias gariepinus

A functional morphological approach to the scaling of the feeding system in the African catfish, Clarias gariepinus

Effects of size are pervasive and affect nearly all aspects of the biology of animals and plants. Theoretical scaling models have been developed to predict the effects of size on the functioning of musculo-skeletal systems. Although numerous experimental studies have investigated the effects of size on the movements of skeletal elements during locomotion and feeding in vertebrates, relatively little is known about the scaling of the muscles and bones responsible for the actual movements. Here, we examine the scaling of external morphology, skeletal elements of the feeding system, and a number of cranial muscles to understand how this may affect the movements observed during suction feeding in the African catfish, Clarias gariepinus. The results show that neither the head nor the cranial elements themselves scale according to geometric similarity models. Relative to head size, distinct changes in the mass and configuration of the feeding structures takes place. Unexpectedly, different cranial muscles show different scaling patterns that ultimately all lead to a

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Biophysics of directional hearing in the American alligator (Alligator mississippiensis)

Biophysics of directional hearing in the American alligator (Alligator mississippiensis)

Physiological and anatomical studies have suggested that alligators have unique adaptations for spatial hearing. Sound localization cues are primarily generated by the filtering of sound waves by the head. Different vertebrate lineages have evolved external and/or internal anatomical adaptations to enhance these cues, such as pinnae and interaural canals. It has been hypothesized that in alligators, directionality may be enhanced via the acoustic coupling of middle ear cavities, resulting in a pressure difference receiver (PDR) mechanism. The experiments reported here support a role for a PDR mechanism in alligator sound localization by demonstrating that (1) acoustic space cues generated by the external morphology of the animal are not sufficient to generate location cues that match physiological sensitivity, (2) continuous pathways between the middle ears are present to provide an anatomical basis for coupling, (3) the auditory brainstem response shows some directionality, and (4) eardrum movement is directionally sensitive. Together, these data support the role of a PDR mechanism in crocodilians and further suggest this mechanism is a shared archosaur trait, most likely found also in the extinct dinosaurs.

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X-ray Topographic and Polarized Optical Microscopy Studies of Inversion Twinning in Sodium Chlorate Single Crystals Grown in the Presence of Sodium Dithionate Impurities

X-ray Topographic and Polarized Optical Microscopy Studies of Inversion Twinning in Sodium Chlorate Single Crystals Grown in the Presence of Sodium Dithionate Impurities

from the center of an untwinned single crystal (i.e., that shown in uncut form in Figure 4c) together with a schematic sketch (Figure 8b) highlighting the main features shown. It is interesting to note the comparatively high crystal perfection of this doped crystal, notably revealing surprisingly few dislocations together with contrast due to growth striations in parallel to the {1 ̅ 1 ̅ 1 ̅ } type growth sector surfaces. Such striations are usually referred to as being caused by nonuniform impurity incorporation and/or structural perturbations at the growing front. Also striking is the slight curvature of the growth front which is also evident from the external morphology of the Figure 5. Photograph of plate I, cut parallel to (110), of the twinned

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Emmidolium excavatum d’Orchymont (Coleoptera: Hydrophilidae: Sphaeridiinae) confirmed in Africa and the Arabian peninsula

Emmidolium excavatum d’Orchymont (Coleoptera: Hydrophilidae: Sphaeridiinae) confirmed in Africa and the Arabian peninsula

The external morphology of Emmidolium is highly similar to the Neotropical species Oosternum sculptum Bruch, 1915. Emmidolium is not closely related to the genus Oosternum Sharp, 1882, which belongs to a group of Gondwanan genera characterized by a crescent-like male sternite 9 lacking a median projection and median lobe with restricted antero-posterior movability, attached to the base of parameres. On the other hand, Emmidolium and Ooster- num sculptum share the following external characters: (1) very coarse punctation of the body surface; (2) excised anterior margin of clypeus; (3) mentum with a deep median depression; (3) plate-like median portion of prosternum (narrow in O. sculptum); (4) pronotum with six longitudinal ridges; (5) lateral portion of pronotum defl exed, bearing a ridge forming a false pronotal margin; (6) alternate intervals of elytra highly costate; (7) elevated portion of metaven- trite nearly reaching its lateral margins. All these characters are very uncommon among other megasternine taxa and have to be considered as convergent until a more detailed phylogenetic analysis can be performed. Both Oosternum sculptum and Emmidolium represent extremely sculptured relatives of ‘usual looking’ (i.e. non-sculptured) megasternine taxa and the trends in their morphology are similar. Therefore, it seems that the change from non-sculptured to extremely sculptured morphology can lead to a parallel (i.e. not independent) change of external characters, resulting in a similar morphology in distantly related taxa. This suggests that extremely sculptured taxa may cause problems when external morphology will be used for phylogenetic analysis of the tribe Megasternini.

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A Comparative Study of Spore Morphology of Some Pteridoideae Subfamily Genera

A Comparative Study of Spore Morphology of Some Pteridoideae Subfamily Genera

Our studies and eventually received original spore micrographs revealed common characters of external morphology of spores that are distinctive to the subfamily Pteridoideae: spores are triangular-roundish, laesura rays are straight and merged into roller-like sporoderm thickening, there are tubercles on the surface of a spore, and in some cases “cerebriform” folds, exosporium surface without excrescences. The study of spores’ morphology of species of the genera Afropteris, Jamesonia and Taenitis, revealed the characters belonging exclusively to these species. Trapezoidal form of Afropteis repens, clearly observed in the equatorial position of the spore, and justifies its indication by Alston as a separate genus 9 . Exosporium of Afropteis

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Direct evidence for the importance of endothelium derived nitric oxide in vascular remodeling

Direct evidence for the importance of endothelium derived nitric oxide in vascular remodeling

ied. Possible differences that can account for the smaller re- duction in diameter seen in rodents may be age, species, or the duration of the ligation. It is clear that vascular remodeling in response to increased or decreased flow is highly dependent on age, i.e., older animals exhibit less remodeling (3, 31). An- other potential caveat of the mouse model described in this study is the inability to measure the flow reduction initiated by left external carotid ligation. Accurate measurements of abso- lute blood flow by velocimetry in conduit vessels is difficult in mice and indirect measurements by Doppler flowmetry are compromised by relative measurements of flow and the diffi- culty in standardizing flows between vessels and animals. Irre- spective of flow measurements, in this study, the decrease in LC diameter after external carotid artery ligation and the de- crease in medial nuclei number is consistent with flow-depen- dent remodeling toward a smaller vessel.

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Molecular, morphological and acoustic identification of Eumops maurus and Eumops hansae (Chiroptera: Molossidae) with new reports from Central Amazonia

Molecular, morphological and acoustic identification of Eumops maurus and Eumops hansae (Chiroptera: Molossidae) with new reports from Central Amazonia

External and craniodental characters measured are based on Eger (1977) and Freeman (1981), and were recorded in millimeters (mm) using digital calipers accurate to 0.1 mm (Fig. 2). Body mass was recorded in grams (g) with a Pesola spring scale (accuracy of 0.5g). Measurements are defined as follows: total length (TL); tail (TAIL); thumb length (ThL); nail (Na); calcar length (Cal); antitragus width (AntW); antitragus height (AntH); hind foot length (HF); ear length (E); forearm length (FA); tibia length (TiL); fourth metacarpal length (MET-IV); first phalanx of the fourth digit (PHA1-IV); greatest length of the skull (GLS); condyloincisive length (CIL); zygomatic breadth (ZB); postorbital breadth (PB); braincase breadth (BB); maxillary toothrow length (MTRL); breadth across molars (BAM); breadth across canines (BAC); mandibular toothrow length (MANDL) and mandibular length (MANDLT).

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Equality in between Iterative Soft Dilation and Iterative Soft Open in Multi Scale Environment

Equality in between Iterative Soft Dilation and Iterative Soft Open in Multi Scale Environment

In this paper a fundamental rule called EQUALITY is discussed in multi scale and iterative environment. It will fill up gap ,on the fundamentals of mathematical soft morphology. Till now applications are discussed in various papers by various researchers,but fundamental properties are not touched. More over iterative morphology is having broad applications. so discussion of fundamental property in this context ,will lead to development of this area. Understanding of fundamental properties of any area will lead to development and expansion of that area, which will lead to excellent applications.

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Relationships between external and internal udder measurements and the linear scores for udder morphology traits in dairy sheep

Relationships between external and internal udder measurements and the linear scores for udder morphology traits in dairy sheep

Sample statistics of udder morphology measure- ments and linear scores for Tsigai (T), Improved Walachian (IW) and Lacaune (LC) ewes are sum- marized in Table 1. The average udder size of LC ewes was larger than in Slovak native dairy sheep breeds T and IW. Average udder depths of individual breeds were: 134 mm (T), 136 mm (IW) and 184 mm (LC). McKusick et al. (2000) measured higher av- erage udder depth for multiparous East Friesian ewes (197 mm). Rovai et al. (1999) found average udder depth 172 mm for Manchega and 178 mm for Lacaune breed. The average cross-section areas of cistern were also much larger in LC than in T or IW for both variants of measurements, from the side and from the bottom. On the other hand, teats were positioned more horizontally in LC ewes. The

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DEVLOPMENT AND EVALUATION OF MUCOADHESIVE MICROSPHERE OF RALOXIFENE HYDOCHLORIDE

DEVLOPMENT AND EVALUATION OF MUCOADHESIVE MICROSPHERE OF RALOXIFENE HYDOCHLORIDE

Muccoadhesive chitosan microspheres of Reloxifene were prepared for oral administration with the aim of avoiding the first pass effect and improve the bioavaibility. A series of batches of microspheres were prepared by emulsion solvent diffusion technique in which drug to polymer ratio was used to prepare the different formulation. The microspheres were evaluated for physical characteristics such as particle size, particle shape and surface morphology by scanning electron microscopy, drug entrapment efficiency, in vitro mucoadhesion, and in vitro drug release characteristics. The microspheres had a mean particle size of 36.47 + 3.39 mm, suitable for administration. Electron microscopy revealed that microspheres were spherical with nearly smooth surface morphology. Application of in vitro drug release data to various kinetic equations indicated matrix diffusion controlled drug release from chitosan microspheres.

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Morphological predictors of swimming speed: a case study of pre settlement juvenile coral reef fishes

Morphological predictors of swimming speed: a case study of pre settlement juvenile coral reef fishes

There was no evidence that the model fit differed among taxonomic groups, despite the inclusion of five different orders of fishes. This suggests that body morphology alone appears sufficient to explain the bulk of the differences in swimming performance among taxonomic groups and that phylogenetic constraint of body morphology may limit maximum sustainable swimming speeds. The fastest groups are the Beryciformes (Holocentrids), followed by the Siganidae and the Acanthuridae, both members of the Perciformes. These groups appear to have evolved similar streamlined body forms, not unlike that of the tunas (also from the order Perciformes), optimized for fast steady swimming (Blake, 2004). These morphological adaptations have evolved independently in a number of phylogenetically distant groups (Blake, 2004). A handful of species (notably those from the orders Tetraodontiformes and Lophiiformes), exhibit exceptionally slow swimming speeds, having body morphologies clearly incapable of sustained swimming at high speed. Such species must have quite unique ecological characteristics that allow their slow swimming existence, and it is perhaps not surprising that at least some of their representatives exhibit factors such as chemical or cryptic defenses from predation. The majority of fishes swim at intermediate speeds, with most families swimming between 20 and 50·cm·s –1 . It is at these medium range speeds that the largest variation in body form is found, and may reflect the fact that a diversity of body morphology is probably adequate for producing a reasonable level of swimming proficiency. For medium pace swimmers, design factors beneficial to other swimming skills, such as acceleration or maneuverability, may result in a diversity of morphological shape.

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Short communication:The relationships between gut length and prey preference of three pipefish (Syngnathus acus, Syngnathus typhle, Nerophis ophidion Linnaeus, 1758) species distributed in Aegean Sea, Turkey

Short communication:The relationships between gut length and prey preference of three pipefish (Syngnathus acus, Syngnathus typhle, Nerophis ophidion Linnaeus, 1758) species distributed in Aegean Sea, Turkey

In order to detect dietary shifts, morphometric measurements of 142 S. acus, 80 S. typhle and 21 N. ophidion specimens have been used. After capturing, specimens were preserved in 10 % formalin. To determine if dietary shifts are correlated with feeding morphology, total length (TL, mm), gut lengths (GL, mm), total weight (W, g) and gut weight of each specimen was measured in laboratory. Later, fish samples were dissected in laboratory and gut contents were sorted out by group levels under the binocular microscope, and analysed using numerical occurrence (NO %) and frequency occurrence (FO %) methods (Leonard et al, 2010). An index of fullness was also calculated. Since the syngnathids have a relatively undifferentiated gastrointestinal tract, stretched gut length of the pipefish specimens was measured between oesophagus and intestine with 0,01mm with digital caliper (Teixeira and Musick, 1995) (Figs. 2,3,4).

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The dorsal organ and other cuticular structures in larval and adult crustacea : an ultrastructural study

The dorsal organ and other cuticular structures in larval and adult crustacea : an ultrastructural study

trilobites, Raymond (1920) interpreted this structure as that which evolved later as the posterior zoeal spine of Crustacea. Stormer’s (1930) studies on the median tubercle of Tretaspis seticornis (Trinucleidae) revealed the external morphological features of what could be considered the homologous dorsal organ found by Caiman (1904) and Hansen (1921) in recent Crustacea Malacostraca. Stormer’s description of the organ was "5 distinct pits arranged in a deformed square with a central pit". Pit dimensions were larger in young specimens (0.1 mm) than in adults (0.028 mm). Thus the author concluded that the median tubercle was best developed in the younger specimens, and described the central pit as the opening of the eye- and the four pits indicated the ocelli. Thus it was regarded as a true median eye. Lenses were not found as in the lateral eyes. Hanstrom (1934), on the other hand, indicated that, at least in the Trinucleidae, the median tubercle seemed to have some sort of "sensory complex" similar to that of recent syncarids.

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Body condition evaluation, external biometrics measurements and morphology of digestive tube of red cowled cardinals

Body condition evaluation, external biometrics measurements and morphology of digestive tube of red cowled cardinals

Guerra R.R., Luna A.S.L., Siqueira R.A., Firmino M.O., Cleub C., Guerra M.V.S.F. and Cavalcanti T.A. 2016. [Body condition evaluation, external biometrics measurements and Paroaria dominicana Linnaeus, 1758) of wild life apprehended in Paraíba, Brazil: releasing projects subsidies.] Paroaria dominicana is a bird Because of its song and color qualities is one of the main targets of wild animal trafficking in Brazil. This study aimed to evaluate the external and organ biometry of the digestive tube, as well as the histological aspects of this system and the body condition of specimens from apprehensions made by the Wild Animal Screening Center, in order to provide subsidies for taxonomic classification, clinical, nutritional and species preservation management, as body condition evaluation, external biometrics measurements and tube digestive morphological analysis of 20 P. dominicana apprehended in seized specimens presented unfavorable body conditions, which were related the visceral topography and histology of the digestive system was consistent with those of other birds, but the external and internal biometry presented differences. The results body condition analysis of seized animals is an important tool that should be considered in evaluations at Screening Centers, in order to achieve a better nutritional and/or clinical management before releasing projects, thus increasing the project success. The results will provide n, as well as corroborate further clinical, nutritional, preservationist

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Three dimensional visualisation and morphometry of bone samples studied in microcomputed tomography (micro-CT)

Three dimensional visualisation and morphometry of bone samples studied in microcomputed tomography (micro-CT)

This article highlights the utility of micro-computed tomography (micro-CT) for cha- racterising microscale bone morphology. For this purpose we tested selected samples of the human bones (Wormian bone, rib, lumbar vertebra) to reconstruct external and internal morphological features. Selected bony samples were investigated using a micro-CT scanner (Skyscan 1172, N.V., Aartselaar, Belgium). The image resolution of scans varied from 5 to 27 µm/pixel depending on the bone sample. We used CTvox software (by Skyscan) to perform volume rendering of the sam- ples. Further, 3-dimensional geometrical models were reconstructed using the CTvol application. Such models enabled graphical distinction between osseous components of various morphology and were used to visualise the Haversian canal system inside the compact bone of the rib. Applying a modified transfer function for volume rendering we presented the overall morphology of the Wormian bone and small vascular channels penetrating its interior. As an example of quantitative analysis based on micro-CT scans we compared the trabecular structure of the lumbar vertebrae with CTAn software. Significant differences in percent bone volume (BV/TV) were determined. Micro-CT was found to be a very accurate and helpful method to study small anatomical structures of the bones in micro scale. (Folia Morphol 2014; 73, 4: 422–428)

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