The buoyancy of the integument of Atlantic bottlenose dolphins (Tursiops truncatus): Effects of growth,reproduction, and nutritional state

In Atlantic bottlenose dolphins (Tursiops truncatus) the thickness and lipid content of blubber (the integument's specialized hypodermis) varies across ontogeny and with reproductive and nutritional state. Because the integument comprises up to 25% of total body mass in this species, ontogenetic changes in its lipid content may influence whole body buoyancy. The density and volume of the integument were measured and its buoyancy calculated across an ontogenetic series of dolphins and in pregnant and emaciated adults (total n= 45). Regional differences between the metabolically labile trunk integument and the structural tailstock integument were also investigated. Mean densities of both trunk and tailstock integument were similar across life history categories (trunk = 1,040.7 ± 14.1 kg/m³; tailstock = 1,077.1 ± 21.2 kg/m³) and were statistically similar to the density of seawater (1,026 kg/m³). The mean buoyant force of integument from the trunk (−1.01 ± 1.74 N) and tailstock (−0.30 ± 0.21 N) did not vary significantly across ontogeny. In contrast, pregnancy and emaciation did influence the integument's buoyancy, which ranged between 9 N and −45 N in these categories. Although neutral during growth, the integument's contribution to whole body buoyancy can be influenced by an individual's reproductive and nutritional status.     

Pterospora floridiensis,a new species of acephaline gregarine (Apicomplexa) from the maldanid polychaete Axiothella mucosa in St. Andrew Bay,Florida

Pterospora floridiensis, a new species of acephaline gregarine from the body cavity of the bamboo worm Axiothella mucosa (Polychaeta: Maldanidae), is described. The gamont stage is distinctive and possesses a central cytoplasmic mass and two elongate trunks that bifurcate repeatedly and comprise approximately 60% of the total cell length. The gamont averages 198 (50–545) × 71 (25–180) m (N= 45, 43) from the tip of the trunks to the anterior (the junctional site with the other gamont in syzygy). Gametocysts average 402 (297–545) × 304 (149–495) m (N= 37). The oöcysts measure 22.5 (20.5–23.5) × 8.3 (7.0–10.0) m (N= 30) and possess an internal capsule (average length = 13.9 m, N= 30) containing the sporozoites and aliform wings on the epispore.     

Coccidia of Malaysian Mammals: New Host Records and Descriptions of Three New Species of Eimeria*

SYNOPSIS. In a survey of parasites of wild mammals of Malaysia 3 new species of Eimeria were found. Eimeria tupaiae sp. n. is described from the common tree shrew, Tupaia glis. Its ellipsoidal to spherical, 3-layered oocysts average 20 × 19 μm. A micropyle is absent; an oocyst residuum and polar granule are present. Ellipsoidal sporocysts average 11 × 7 μm. A sporocyst residuum and Stieda body are present. Eimeria ptilocerci sp. n. is described from the pen-tail tree shrew, Ptilocercus lowii. The ellipsoidal to spherical, 2-layered oocysts average 23 × 20 μm. A micropyle and oocyst residuum are absent; polar granules are present. The ellipsoidal sporocysts average 13 × 7 μm. A sporocyst residuum and Stieda body are present. Eimeria muuli sp. n. is described from the pencil-tailed tree mouse, Chiropodomys gliroides. The ellipsoidal single-layered oocysts average 25 × 19 μm. A micropyle and oocyst residuum are absent; a polar granule is present. The ellipsoidal sporocysts average 13 × 8 μm. A sporocyst residuum and Stieda body are present. In addition, new host records are reported as follows: E. miyairii Ohira from Whitehead's rat Rattus whiteheadi and the Malaysian wood rat, R. tiomanicus; E. separata Becker & Hall from Mueller's rat, R. muelleri, the chestnut rat, R. fulvescens, and the Malaysian wood rat, R. tiomanicus; E. nieschulzi Dieben from the red spiny rat, R. surifer and the chestnut rat, R. fulvescens; and E. callosciuri Colley from the grey-bellied squirrel, Callosciurus caniceps and the black-banded squirrel, C. nigrovittatus.     

Epiphytic succession on tree trunks in a mixed oak-cedar forest,Kumaun Himalaya

The epiphytes present at about breast height on trunks of different size were studied for three major tree species in a seasonally wet forest at 2050 m altitude in the Kumaun Himalaya: Cedrus deodora, Quercus floribunda and Q. leucotrichophora. The total biomass and species number per unit trunk area, were found to increase with trunk size. It was supposed that the results indicated a succession in the type of epiphytic cover from young trunks to older trunks.The amount of loose material (plant remains and soil) per unit area of trunk increased with increasing girth. The C:N ratio in this material was initially very high on the oaks (129–197) and declined with increasing trunk size (to 73–78); the ratio was constant across girth classes in the cedar (86–87).Bryophytes produced most biomass on most trunks; next to them were lichens on the smallest trunks, and flowering plants on the largest. The number of species of epiphytes was similar on all three host species. The results are discussed in relation to contemporary ideas on diversity and strategies.Nomenclature follows: Ganguli (1972, 1977 & 1980); Kashyap (1929); Nayar (1970); Osmaston (1927).Financial support from the Council of Scientific and Industrial Research, Delhi and University Grants Commission, New Delhi is gratefully acknowledged.     

Effects of snow pressure on growth form and life history of tree species in Japanese beech forest

Abstract. In the cool temperate zone in Japan Fagus crenata (beech) is a highly dominating climax species, especially in the snow-rich regions at higher altitudes. The explanation for this dominance was studied with special reference to the tolerance of tree trunks to snow pressure. Traits of six tree species: trunk bend, trunk height decrease, trunk damage and basal sprouting rate were measured in Fagus forest in the Echigo Mountains, central Japan along a snow pressure gradient. The following general trends were recognized: (1) trunk bend and trunk height decrease; (2) snow pressure caused trunk injury; (3) when the trunk bend exceeded a critical angle, the number of sprouts increased remarkably. Although the tolerances were different among the six species, most of them were seriously damaged by snow pressure, and many trunks were reduced in size. On the other hand, many sprouts emerged from deformed trunks and contributed to the maintenance of the population under heavy snow pressure. F. crenata was the only species whose trunk form and maximum size were hardly influenced by snow pressure.     

SOME PRYMNESIACEAE (HAPTOPHYTA,PRYMNESIOPHYCEAE) FROM THE MEDITERRANEAN SEA,WITH THE DESCRIPTION OF TWO NEW SPECIES: CHRYSOCHROMULINA LANCEOLATA SP. NOV. AND C. PSEUDOLANCEOLATA SP. NOV.1

Five species belonging to the family Prymnesiaceae (one Prymnesium and four Chrysochromulina) have been identified in cultures obtained from water collected in the Bay of Banyuls‐sur‐Mer (Mediterranean Sea, France) using LM, SEM, and TEM. Two are described as new species, Chrysochromulina lanceolata sp. nov. and C. pseudolanceolata sp. nov. Both species are large and lanceolate with an acute posterior and two anterior arms. They are easily detectable with LM but difficult to distinguish to species level with live cells, without experience. EM reveals two completely different scale patterns in the two species. Cells of C. lanceolata are 21–38 μm long, 7–12 μm wide, and 3–7 μm thick. They possess two subequal flagella (30–51 and 29–44 μm), and the haptonema is shorter than the flagella (23–37 μm). The cell body is covered by plate and spine scales. Cells of C. pseudolanceolata sp. nov. are slightly smaller (15–18 × 6–8 μm) with more rounded extremities, two subequal flagella (19–26 and 17–24 μm), and the haptonema is longer than the flagella (about 35 μm). Three types of plate scales are observed in this species. Other findings are C. alifera Parke et Manton and C. throndsenii Eikrem (a new record for the Mediterranean Sea). Prymnesium faveolatum Fresnel, a new toxic species recently described, is illustrated with both LM and SEM.     

Comparative surface morphology of marine coelomic gregarines (Apicomplexa, Urosporidae): Pterospora floridiensis and Pterospora schizosoma

Two species in the aseptate gregarine genus Pterospora from the Pacific and Gulf coasts were analyzed by scanning electron microscopy, which revealed characteristics not reported in other gregarines. The gamonts of these species had branching trunks that ended in terminal digits, and both species moved by cytoplasmic streaming and peristalsis. Pterospora floridiensis had surface pits and tracts of parallel ridges that bended and connected with one another. Pterospora schizosoma had irregular-shaped surface swellings that were usually arranged in rosette patterns. These unique surface features have not been reported for other gregarines, and are strikingly different from the surface features of many septate and aseptate gregarines that inhabit the intestinal lumena of their hosts and move by gliding. The correlation of Pterospora's unique pellicular features to the habitat and cytoplasmic streaming characteristic of the genus may be significant, and may reflect an adaptation for development in coelomic environments.     

Assessment of the mass,length, center of mass,and principal moment of inertia of body segments in adult males of the brown anole (Anolis sagrei) and green,or carolina,anole (Anolis carolinensis)

This study provides a morphometric data set of body segments that are biomechanically relevant for locomotion in two ecomorphs of adult male anoles, namely, the trunk‐ground Anolis sagrei and the trunk‐crown Anolis carolinensis. For each species, 10 segments were characterized, and for each segment, length, mass, location of the center of mass, and radius of gyration were measured or calculated, respectively. The radii of gyration were computed from the moments of inertia by using the double swing pendulum method. The trunk‐ground A. sagrei has relatively longer and stockier hindlimbs and forelimbs with smaller body than A. carolinensis. These differences between the two ecomorphs demonstrated a clear relationship between morphology and performance, particularly in the context of predator avoidance behavior, such as running or jumping in A. sagrei and crypsis in A. carolinensis. Our results provide new perspectives on the mechanism of adaptive radiation as the limbs of the two species appear to scale via linear factors and, therefore, may also provide explanations for the mechanism of evolutionary changes of structures within an ecological context. J. Morphol., 2012. © 2012 Wiley Periodicals, Inc.     

The formation of several mitochondrial enzymes during the cell cycle in heat-synchronized Tetrahymena pyriformis ST.

The mechanical properties of the endoplasm were determined in oocytes and mature eggs of the starfish, Asterina pectinifera as follows. The cell was first deformed into a dumbbell shape by aspirating it through a circular hole of 35 or 50 μm radius formed in an agar plate of about 150 μm thickness. The movement of endoplasm in the cylindrical part of the cell was determined when a definite pressure was applied between both sides of the plate. Mechanical properties were practically represented by a viscoelastic model (fig. 5a) consisting of a Voigt element and a viscous element connected in series. The strain was proportional to the 0.60 ± 0.17th power of the stress in mature eggs and to the 0.76 ± 0.17th power of the stress in primary oocytes. Viscoelastic coefficients (G, η₁ and η₂ shown in fig. 5) of endoplasm changed in parallel to one another during maturation of the oocyte. They decreased with the breakdown of the germinal vesicle, increased before the extrusion of the first polar body, decreased during and after the first polar-body formation, increased before the extrusion of the second polar body, and decreased during and after the second polar-body formation.     

A New Species of Eimeria from the Golden-Mantled Ground Squirrel, Spermophilus lateralis, in Northern Colorado

Oocysts of Eimeria morainensis n. sp. are described from the golden-mantled ground squirrel, Spermophilus lateralis. in Northern Colorado. The oocysts of E. morainensis are double-walled and subspherical, 20.3 × 19.8 (18.7–26.2 × 17.5–21.2) μm; and the sporocysts are ellipsoid, 12.1 × 6.9 (8.7–13.7 × 6.2–8.7) μm. Oocyst residuum and micropyle are absent, but a polar granule is present. Sporocyst residuum and Stieda body are present. Differences in oocyst characteristics provide the basis for recognition of this new species of Eimeria.     

Morphology of the proboscis of Hubrechtella Juliae (nemertea,pilidiophora): Implications for pilidiophoran monophyly

The proboscis of Hubrechtella juliae was examined using transmission electron microscopy, scanning electron microscopy, and confocal laser scanning microscopy to reveal more features of basal pilidiophoran nemerteans for morphological and phylogenetic analysis. The proboscis glandular epithelium consists of sensory cells and four types of gland cells (granular, bacillary, mucoid, and pseudocnidae‐containing cells) that are not associated with any glandular systems; rod‐shaped pseudocnidae are 15–25 μm in length; the central cilium of the sensory cells is enclosed by two rings of microvilli. The nervous plexus lies in the basal part of glandular epithelium and includes 26–33 (11–12 in juvenile) irregularly anastomosing nerve trunks. The proboscis musculature includes four layers: endothelial circular, inner diagonal, longitudinal, and outer diagonal; inner and outer diagonal muscles consist of noncrossing fibers; in juvenile specimen, the proboscis longitudinal musculature is divided into 7–8 bands. The endothelium consists of apically situated support cells with rudimentary cilia and subapical myocytes. Unique features of Hubrechtella's proboscis include: acentric filaments of the pseudocnidae; absence of tonofilament‐containing support cells; two rings of microvilli around the central cilium of sensory cells; the occurrence of subendothelial diagonal muscles and the lack of an outer diagonal musculature (both states were known only in Baseodiscus species). The significance of these characters for nemertean taxonomy and phylogeny is discussed. The proboscis musculature in H. juliae and most heteronemerteans is bilaterally arranged, which can be considered a possible synapomorphy of Hubrechtellidae + Heteronemertea (= Pilidiophora). J. Morphol. 274:1397–1414, 2013. © 2013 Wiley Periodicals, Inc.     

Horizontal and vertical movements of host‐seeking Ixodes pacificus (Acari: Ixodidae) nymphs in a hardwood forest

The nymph of the western black‐legged tick (Ixodes pacificus) is an important bridging vector of the Lyme disease spirochete (Borrelia burgdorferi) to humans in the far‐western United States. The previously unknown dispersal capabilities of this life stage were studied in relation to logs, tree trunks, and adjacent leaf‐litter areas in a mixed hardwood forest using mark‐release‐recapture methods. In two spatially and temporally well‐spaced trials involving logs, the estimated mean distances that nymphs dispersed ranged from ≈0.04 to 0.20 m/day on logs vs 0.11 to 0.72 m/day in litter. Prior to recapture in either trial and within the confines of the sampling grids, the greatest estimated dispersal distances by individual nymphs released on logs, and in litter 0.5 m or 1.5 m from logs, were 2.4, 3.0, and 3.0 m, respectively. Nymphs released on logs or litter tended to remain within the same biotopes in which they were freed while host‐seeking. In two simultaneous trials involving trunks spaced close‐at‐hand, nymphs released at the trunk/litter interface on all four aspects collectively dispersed a mean of 0.353 m/day on trunks vs 0.175 m/day in litter. In either trial, the greatest distances that recaptured nymphs climbed trunks, or dispersed in litter in an encircling 3‐m grid, were 1.55 m and 2.97 m, respectively. Nymphs ascending trunks did not exhibit a preference for any one aspect, and the B. burgdorferi‐infection prevalences in nymphs that climbed trunks (3.2–4.0%) did not differ significantly from those that moved horizontally into litter (10.5–17.6%). We conclude that I. pacificus nymphs use an ambush host‐seeking strategy; that they disperse slowly in all biotopes studied; that they usually continue to host‐seek in or on whatever substratum they access initially; and that B. burgdorferi‐infected nymphs are as likely to move horizontally as vertically when offered a choice.     

New method for rapidly estimating population densities of the concealed wood‐borer Monochamus alternatus (Coleoptera: Cerambycidae) in the field

To rapidly estimate pine sawyer, Monochamus alternatus Hope, population densities in forests, the vertical distributions of M. alternatus oviposition sites and larvae on infested Masson pines (Pinus massoniana Lamb.) were studied. Results showed that the number of oviposition sites on sections of trunks between 0 and 2 m above ground was significantly greater than on sections of trunk above 2 m, and the vertical distribution had a significant logarithmic relationship with trunk height. The larval number of M. alternatus on dead infested trees had a significant difference among heights of trunks. Sections on trunks at 2–4 m usually contained the largest number of M. alternatus larvae, while the number of larvae on trunks above 10 m declined significantly, as well as in the 1 m section of trunk at the base. The vertical distribution of M. alternatus larvae on dead infested pines showed a distinct parabolic relationship with trunk height. The number of oviposition sites of M. alternatus on infested Masson pine trunks revealed a significant exponential relationship with the diameter at breast height (DBH) of trees. A significant positive linear relationship also was observed between M. alternatus larval number and DBH on the host pine trees, as well as between the numbers of larvae and oviposition sites on an individual tree. The total number of larvae in an infested tree could be calculated easily using an established equation, through counting the number of oviposition sites at 3–4 m of trunk aboveground. This study developed a practical method for rapid estimation of M. alternatus populations.     

The comparative gross anatomy of the arteria cerebri media in the green monkey (Cercopithecus aethiops) and olive monkey (Papio anubis)

The gross anatomy of the arteria cerebri media inCercopithecus aethiops andPapio anubis was studied and compared statistically. Several features appeared to be species characteristic. InCercopithecus aethiops the first branch, r. striati, arose directly from the main artery, however, inPapio anubis, r. striati arose from r. orbitales the second major branch. InCercopithecus aethiops, r. orbitales and r. frontales arose by a common trunk from the a. cerebri media and inPapio anubis these two branches had separate origins. In both species r. temporales arose from two trunks, on either side of the a. sulcus centralis. Each trunk of r. temporales divided into two or three branches inCercopithecus aethiops and three or four branches inPapio anubis. The last portion of the a. cerebri media, r. parietales, divided into two trunks inCercopithecus aethiops and continued as a single trunk inPapio anubis. In the former, r. parietales sent one or two branches to the sulcus intraparietalis and sulcus lunatus while sending one branch to the gyrus postcentralis. In the latter, r. parietales sent two or three branches to the sulcus intraparietalis, three or four to the sulcus lunatus and one to the gyrus postcentralis.     

STUDIES ON MORPHOLOGY AND DEVELOPMENT OF OEDMEUS ASIATICUS ENTOMOPOXVIRUS PROPAGATED IN OEDALEUS INFERNALIS*

Abstract The morphological characteristics and development of Oedaleus asiaticus entomopoxvirus propagated in Oeddeus infernalis are reported. This virus mainly infected host's fat bodies and hemocytes. Three kinds of spheroids were observed during propagation: big spheroid (30. 41 μm × 25. 40 μm), ellipsoid (6. 58 μm × 4. 78 μm) and small spheroid (3. 35 μm × 2. 60 μm). The virions embeded in them were oval, measuring 230 nm × 176 nm. The typical characteristic of poxviruses as spherical units with the mulberry-like surface could be seen under transmission electron microscope. The lateral body was cylinder-shaped. The rope-like substances in the core folded back only once; therefore two spots in transverse sections were seen. The development of the virions included four stages: the appearance of viro-plasm, the formation of spherical particles, the differentiation of core and capsid. The grasshoppers only in the same genus could be infected by this virus.     

Analysis of factors affecting bird predation on gypsy moth egg masses by using Holling’s disc-equation

1. Birds’ predation on gypsy moth egg masses deposited on tree trunks was quantitatively evaluated in a birch forest at Bibai, Hokkaido during the four winter seasons from 1974 to 1978.
2. Holling's disc-equation could be successfully applied to describe the relationship between the total egg consumption by birds and the density of egg masses. A rapid method for fitting the disc-equation to observed data was proposed based on the study byShinozaki andKira (1961).
3. Appreciable amounts of predation were observed only during the period when the depth of snow cover on the ground exceeded 1 m, while the egg masses deposited on lower parts of tree trunk below 1 m level suffered from only slight predation. It was therefore presumed that deep snow cover made the predator birds to change their feeding place from ground vegetation to tree trunks.
4. The duration of the period with snow accumulation deeper than 1 m was introduced into the disc-equation as an additional parameter. The values calculated by the resultant formulation agreed with the observed values in respective years satisfactorily.
5. There were circumstantial evidences that the great tit, Parus major, was one of the important predators concerned.

     

Bdelloid Rotifers from Lakes above 1700 m in Western Italian Alps,with Taxonomic Notes on Dissotrocha macrostyla

Benthic and periphytic bdelloid communities from 16 alpine lakes from 1700 to 2850 m above sea level in Sesia Valley (Piedmont region, North‐western Italy), sampled during summer 2001 and 2002, were analyzed. Seventeen species were identified from these species‐poor communities, with 1 to 6 species each. Dissotrocha macrostyla and Philodina citrina were the most common species, present in 10 lakes while 9 species were collected from one lake only. New morphological details from S.E.M. pictures of Dissotrocha macrostyla revealed that Dissotrocha macrostyla tuberculata (Gosse , 1886) is only a seasonal morphotype. Its different appearance is due to the presence of locally distributed microscopic mucous bubbles (diameter 1.41 ± 0.18 μm) on the trunk surface, produced by the rotifer itself under stressful conditions.     

Oxygen consumption of a Chaoborus species from a neotropical reservoir (socuy reservoir,Venezuela)

Oxygen consumption of all four larval instars of a Chaoborus species from Socuy Reservoir in western Venezuela was studied under laboratory conditions at 25°C. On a logarithmic basis, oxygen consumption per organism increased as a smooth, linear function of body weight (0.49 power of body weight). Observed rates were lower than other Chaoborus species with comparable body weight at the same temperature. Oxygen consumption per unit weight decreased from smaller to large instar larvae. With the exception of instar I, values of oxygen consumption per unit weight were lower than values reported for other Chaoborus species. The results suggest that our species have low energy demands for maintenance, and are consistent with suggestions about high efficiency in use of energy in genus Chaoborus.     

Hemoglobin-containing cells of Neodasys (Gastrotricha,Chaetonotida). I. Morphology and ultrastructure

The overall anatomy of Neodasys as well as data for hemoglobin-containing cells are described. Hemoglobin-containing cells are shown to be mesodermal specializations constituting approximately 14% of the animal's total body volume (4.87 ± 10⁴ μl). These globular cells (10–14 μm) are situated in two longitudinal rows, each dorsolateral to the straight gut. Branches from the cells enwrap perikarya of muscle and nerve cells whose mitochondria are found just below their respective plasmalemmata in intimate association with the hemoglobin-containing cells. The ground substance of the cytoplasm and nucleoplasm of these nearly organelle-free cells is extremely electron-dense and is presumed to represent the hemoglobin molecules. Locomotion analyses indicate that the cells can undergo a threefold change in linear dimension in 0.25 seconds, raising the possibility of convective mixing in these cells. Structural and ultrastructural comparisons with similar cells in adults of other species of Gastrotricha indicate that the hemoglobin-containing cells of Neodasys may be homologous to the socalled Y cells of other species, some of which contain myofilaments. A muscle-cell origin is considered for the evolution of hemoglobin-containing cells of Neodasys.