Vertical movement and behavior of the ocean sunfish, Mola mola, in the northwest Atlantic

Pop-up satellite archival tags (PSATs) were attached to 31 ocean sunfish, Mola mola. in the Northwest Atlantic between 2005 and 2008, in order to examine their vertical movement and behavior. Tags remained attached from 7 to 242 days, with a mean attachment period of 107.2 ± 80.6 (SD) days. Fish spent greater than 30% of their time in the top 10 m of the water column, and over 80% of time in the top 200 m. The maximum depth recorded by any fish was 844 m. Temperatures experienced by tagged fish ranged from 6 to 30 °C. Vertical behavior of M. mola changed over short-term and seasonal scales. Ocean sunfish in northeastern US waters in the summer months inhabited shallower depths and spent more time at the surface than those that moved south in the winter and spring. This shift from shallow to deeper depths was especially apparent when fish entered the Gulf Stream, where they spent little time at the surface and dove to depths of 400-800 m. A diel pattern was observed in vertical behavior. Tagged fish spent more time at depth during the day and inhabited shallower waters at night. There was no observed relationship between the amount of time per day that fish spent in cold water (< 10 °C) and the amount of time fish spent near the surface (0-6 m), indicating a lack of evidence for M. mola basking at the surface as a mechanism for behavioral thermoregulation.     

Mitochondrial genomes and phylogeny of the ocean sunfishes (Tetraodontiformes: Molidae)

We determined the complete nucleotide sequences of the mitochondrial genomes for the three currently recognized species of ocean sunfish: Mola mola, Masturus lanceolatus, and Ranzania laevis (Tetraodontiformes: Molidae). Each genome contained the 37 genes as found in teleosts, with the typical gene order in teleosts. Bayesian, maximum-likelihood, and maximum-parsimony analyses were conducted with the data set comprising concatenated nucleotide sequences from 36 genes (excluding the ND6 gene) of three molids and four outgroups (three tetraodontiforms plus a caproid). The resultant trees supported monophyly of the Molidae and its intrarelationships ((Mola, Masturus), Ranzania), which were congruent with previous morphology-based hypotheses.     

Pericarp anatomy of wild roses (Rosa L., Rosaceae)

The pericarp anatomy of representatives of all subgenera and sections of the genus Rosa was studied. All species have the same basic pericarp structure: it is composed of inner and outer endocarps, mesocarp and exocarp formed by the epidermis and hypodermis. The differences concern mainly the thickness of particular layers, and the shape and size of their cells. Cells of the endocarp and mesocarp are thick-walled. The only exception is Rosa rugosa mesocarp, which is composed of rather thin-walled cells with a large lumen. The endocarp structure of Rosa achenes resembles the drupe of the genus Prunus s.l. and drupelets of Rubus species.     

Early intrauterine embryonic development of the bothriocephalidean cestode Clestobothrium crassiceps (Rudolphi, 1819), a parasite of the teleost Merluccius merluccius (L., 1758) (Gadiformes: Merlucciidae)

The early intrauterine embryonic development of the bothriocephalidean cestode Clestobothrium crassiceps (Rudolphi, 1819), a parasite of the teleost Merluccius merluccius (L., 1758), was studied by means of light (LM) and transmission electron microscopy (TEM). Contrary to the generic diagnosis given in the CABI Keys to the cestode parasites of vertebrates, the eggs of C. crassiceps, the type of species of Clestobothrium Lühe, 1899, are operculate and embryonated. Our LM and TEM results provide direct evidence that an operculum is present and that the eggs exhibit various stages of intrauterine embryonic development, and in fact represent a good example of early ovoviviparity. The intrauterine eggs of this species are polylecithal and contain numerous vitellocytes, generally ∼ 30, which are pushed to the periphery and remain close to the eggshell, whereas the dividing zygote and later the early embryo remain in the egg centre. During early intrauterine embryonic development, several cleavage divisions take place, which result in the formation of three types of blastomeres, i.e. macro-, meso- and micromeres. These can be readily differentiated at the TEM level, not only by their size, but also by the ultrastructural characteristics of their nuclei and cytoplasmic organelles. The total number of blastomeres in these early embryos, enclosed within the electron-dense eggshells, can be up to ∼ 20 cells of various sizes and characteristics. Mitotic divisions of early blastomeres were frequently observed at both LM and TEM levels. Simultaneously with the mitotic cleavage divisions leading to blastomere multiplication and their rapid differentiation, there is also a deterioration of some blastomeres, mainly micromeres. A similar degeneration of vitellocytes begins even earlier. Both processes show a progressive degeneration of both vitellocytes and micromeres, and are good examples of apoptosis, a process that provides nutritive substances, including lipids, for the developing embryo.     

Morphology and anatomy of blackberry pyrenes (Rubus L., Rosaceae) Elementary studies of the European representatives of the genus Rubus L.

This article presents the results of studies on the pyrenes of selected European brambles belonging to different subgenera and sections of the genus Rubus. Differences between the pyrenes of particular species are mainly visible in their shape, size and the outer endocarp sculpture. Numerous SEM photographs revealed that the differentiation of the endocarp surface is due to variations in a thin layer of transition sclereids developing between the outer endocarp and a mesocarp parenchyma. The endocarp structure of the genus Rubus can be used in determining some species belonging to different subgenera, even if generally its significance in the taxonomy of the European Rubus is limited.     

Hydrozoan and protozoan epibionts on two decapod species, Liocarcinus depurator (Linnaeus, 1758) and Pilumnus hirtellus (Linnaeus, 1761), from Scotland

Crabs of the species Liocarcinus depurator and Pilumnus hirtellus, collected on the west coast of Scotland, showed hydrozoan and protozoan epibionts. The epibionts of Liocarcinus depurator were the protozoan Ephelota plana and the hydrozoans Clytia gracilis and Leuckartiara sp. The epibionts of Pilumnus hirtellus were the protozoans E. plana and Zoothamnium sp. For Liocarcinus depurator the number of Ephelota per crab fluctuated between 0 and 47 and the greatest number of suctorians were located on the chelipeds, carapace and anterior pereiopods. The hydrozoans, for Liocarcinus depurator, showed densities of 0-20 (Clytia gracilis on the second pereiopod) and 0-507 individuals per crab (Leuckartiara sp., principally on chelipeds, carapace and the fourth right pereiopod). For Pilumnus hirtellus, Ephelota plana showed densities between 3 and 56 individuals per crab, the greatest number of suctorians being located on the same areas as on Liocarcinus depurator. There was a density of 10-69 individuals per crab of Zoothamnium sp. on Pilumnus hirtellus (located on the carapace). Ephelota plana has not been observed previously as an epibiont on crustacea, nor had Zoothamnium sp. as an epibiont on Pilumnus hirtellus. Both hydrozoans, Leukartiara and Clytia, have not been previously described as epibionts on Liocarcinus depurator. Data about the morphological characteristics and distribution of these epibionts are included.     

Recruitment, early survival and growth of the Mediterranean red coral Corallium rubrum (L 1758), a 4-year study

Recruitment, early survival and growth rates of the precious Mediterranean red coral Corallium rubrum (L 1758) are poorly known. We examined these life history traits by means of artificial long-term settlement plates. Eighteen marble tiles placed off the coast of Leghorn (Tuscany, Italy) at two depths (25 and 35 m) were photographed monthly over the 4-year period from 1998 to 2002. Overall, 864 transparencies were examined to follow the individual life histories of red coral colonies belonging to four successive cohorts. Red coral planulae settled on tiles each year between July and September. Overall, 388 settlers colonized the tiles (244 at 25 m and 144 at 35 m), and their respective densities varied between 12.37±6.1 and 2.75±2.4 dm⁻². Heavy mortality affected these colonies (−24.35±9.12 colonies % y⁻¹), but, after 4 years, the tiles still harboured a persistent population (19±4.97 and 9.75±2.87 colonies dm⁻², respectively, at 25 and 35 m) with positive net recruitment rates. Only in 1999 did the net recruitment rate show a negative trend, although only at the shallower depth. At the same time (late summer 1999), a thermal anomaly affected several epibenthic communities in the Ligurian Sea. After 4 years, the tiles were removed, and the colonies that settled on them were measured. The average annual growth rate of colonies was low (0.62±0.19 mm y⁻¹ in diameter), and a marked reduction in growth with age was observed. Our findings suggest that the populations of this slow-growing long-lived octocoral exhibit a high capacity for colonization and seem to be quite resilient to environmental variability.     

Phylogenetic relationship of two <Emphasis Type="Italic">Mola</Emphasis> sunfishes (Tetraodontiformes: Molidae) occurring around the coast of Japan,with notes on their geographical distribution and morphological characteristics

Phylogenetic analyses were conducted using complete nucleotide sequences of the D-loop in the mitochondrial genome of Mola specimens, collected mainly in Japanese waters, to clarify the genetic features and distribution patterns of Mola sunfishes. Two significantly distinct groups (designated A and B) were present in the genus, with a considerable net nucleotide sequence divergence between the two (8.4%). The two groups occurred sympatrically around the Japanese coast, as previously suggested by Sagara et al. (2005). Group A occurred mostly on the Pacific coast of eastern Japan, while group B was widely distributed along the Kuroshio Current, strongly suggesting different migration routes for each group. The morphological characteristics of the two group specimens were differentiated via the head bump, body proportions and shape of the clavus. Through the addition of Mola sequence data taken from outside Japan to our phylogenetic analyses, three independent groups, including groups A and B, were found, each with a wide geographical distribution, which suggests the presence of at least three independent species within the genus Mola.     

Comparative study on the delignification of Azadirachta indica (L) Del., wood by Chrysosporium asperatum and Trichoderma harzianum

Structural alterations induced in response to degradation by two white rot Basidiomycetes on the secondary xylem of Azadirachta indica (L) Del., was compared. In vitro decay test was employed to investigate the pattern of delignification of Azadirachta wood by Trichoderma harzianum and Chrysosporium asperatum. Wood samples inoculated with both the strains were analyzed for different periods viz. 30, 60, 90 and 120 days after fungal inoculation. Initially there was no appreciable percent weight loss of the wood blocks but later on (after 60 days) it increased rapidly and was found similar for both the strains (43-46% of wood mass). Samples inoculated with both the strains showed dual pattern of degradation i.e. selective delignification in the initial stage followed by simultaneous rot during advance stage of decay. Separation of the cells due to dissolution of middle lamella was the characteristic feature of both strains but in the advanced stage of decay, formation of erosion troughs were conspicuous in all the cell types. Other features such as cell wall thinning, rounded pit erosion, formation of erosion channels and bore holes were also observed frequently. Initially, fungal invasion started through the vessel lumen, followed by all the cell types of the xylem. From the vessels, mycelia entered into the adjacent rays and parenchyma cells through the pits. In advanced stage, degradation was so pronounced that rays were partially or even completely destroyed while many cells including vessels were either deformed or destroyed due to loss of rigidity of their walls. Structural alterations induced in response to C. asperatum and T. harzianum attack is described in details.     

In silico structural and functional modelling of Antifreeze protein (AFP) sequences of Ocean pout (Zoarces americanus, Bloch & Schneider 1801)

Antifreeze proteins (AFPs) are known to polypeptide components formed by certain plants, animals, fungi and bacteria which support to survive in sub-zero temperature. Current study highlighted the seven different antifreeze proteins of fish Ocean pout (Zoarces americanus), in which protein (amino acids sequence) were collected from National Centre for Biotechnology Information and finely characterized using several in silico tools. Such biocomputational techniques applied to figure out the physicochemical, functional and conformational characteristics of targeted AFPs. Multiple physicochemical properties such as Isoelectric Point, Extinction Coefficient and Instability Index, Aliphatic Index, Grand Average Hydropathy were calculated and analysed by ExPASy-ProtParam prediction web server. EMBOSS: pepwheel online tool was used to represent the protein sequences in a helical form. The primary structure analysis shows that most of the AFPs are hydrophobic in nature due to the high content of non-polar residues. The secondary structure of these proteins was calculated using SOPMA tool. SOSUI server and CYS_REC program also run for ideal prediction of transmembrane helices and disulfide bridges of experimental proteins respectively. The modelling of 3D structures of seven desired AFPs were executed by the homology modelling programmes; SWISS MODEL and ProSA web server. UCSF Chimera, Antheprot 3D, PyMOL and RAMPAGE were used to visualize and analysis of the structural variation of the predicted protein model. MEGA7.0.9 software used to know the phylogenetic relationship among these AFPs. These models offered excellent and reliable baseline information for functional characterization of the experimentally derived protein domain composition by using the advanced tools and techniques of Computational Biology.     

Methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and susceptibility to ischemic stroke: A meta-analysis

Associations between 5,10-methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism and ischemic stroke have been reported (Ariyaratnam et al., 2007; Banerjee et al., 2007; Casas et al., 2004), but the results of these studies are inconsistent. To investigate the possible associations between the MTHFR gene polymorphism and ischemic stroke, we performed a meta-analysis. Nineteen case–control studies associated with MTHFR gene C667T involving 2223 cases and 2936 controls were included. Heterogeneity among studies was evaluated with I² and Egger's test and an inverted funnel plot was used to assess publication bias. Odds ratio (OR) was observed to identify the associations. Statistically significant association with ischemic stroke was identified for allele T polymorphism of MTHFR [fixed-effects OR = 1.28, 95% confidence interval (95% CI): 1.17–1.40, P < 0.00001] and marginally significant association was detected with genotype CT of MTHFR (fixed-effects OR = 1.13, 95% CI: 1.01–127, P = 0.04) and genotype TT of MTHFR (fixed-effects OR = 1.43, 95% CI: 1.20–1.70, P < 0.001). The results suggested that the MTHFR C667T genetic polymorphism was significantly associated with increased risk of ischemic stroke.     

Artificial Occurrence of the Fallow Deer, Dama dama dama (L., 1758), on the Island of Rhodes (Greece): Insight from mtDNA Analysis

We investigated the origins of the fallow deer (Dama dama dama) of Rhodes by both morphological and molecular means. Our results show that these deer have homogeneous phenotypic patterns. All specimens fell within the common colour coat variety typical of the wild form. The Rhodian deer appear to be rather small, especially when compared with specimens from central and northern Europe. We then sequenced the HVR-I of 13 deer from Rhodes and compared these sequences with other 31 samples obtained from different European and Anatolian populations of fallow deer. Out of 44 sequences, 23 haploypes were found. When compared to the Turkish and Italian populations, the population of Rhodes revealed lower values of within population genetic diversity. The fallow deer from Rhodes are characterized by an 80-bp mitochondrial DNA (mtDNA) insertion not found elsewhere. As a consequence, all the deer from Rhodes form a tight cluster, distinct from all other fallow deer populations. This uniqueness makes the conservation and management of the Rhodian population particularly urgent.     

Morphometric analysis of fetal development of Cavia porcellus (Linnaeus, 1758) by ultrasonography—Pilot study

Measurements on the growth process and placental development of the embryo and fetuses of Cavia porcellus were carried out using ultrasonography. Embryo, fetus, and placenta were monitored from Day 15 after mating day to the end of gestation. Based on linear and quadratic regressions, the following morphometric analysis showed a good indicator of the gestational age: placental diameter, biparietal diameter, renal length, and crown rump. The embryonic cardiac beat was first detected at an average of 22.5 days. The placental diameter showed constant increase from beginning of gestation then remained to term and presented a quadratic correlation with gestational age (r² = 0.89). Mean placental diameter at the end of pregnancy was 3.5 ± 0.23 cm. By Day 30, it was possible to measure biparietal diameter, which followed a linear pattern of increase up to the end of gestation (r² = 0.95). Mean biparietal diameter in the end of pregnancy was 1.94 ± 0.03 cm. Kidneys were firstly observed on Day 35 as hyperechoic structures without the distinction of medullar and cortical layers, thus the regression model equation between kidney length and gestational age presents a quadratic relationship (r² = 0.7). The crown rump presented a simple linear growth, starting from 15 days of gestation, displaying a high correlation with the gestational age (r² = 0.9). The offspring were born after an average gestation of 61.3 days. In this study, we conclude that biparietal diameter, placental diameter, and crown rump are adequate predictive parameters of gestational age in guinea pigs because they present high correlation index.     

Seed coat development, anatomy and scanning electron microscopy of Harpagophytum procumbens (Devil's Claw), Pedaliaceae

Seed coat development of Harpagophytum procumbens (Devil's Claw) and the possible role of the mature seed coat in seed dormancy were studied by light microscopy (LM), transmission electron microscopy (TEM) and environmental scanning electron microscopy (ESEM). Very young ovules of H. procumbens have a single thick integument consisting of densely packed thin-walled parenchyma cells that are uniform in shape and size. During later developmental stages the parenchyma cells differentiate into 4 different zones. Zone 1 is the multi-layered inner epidermis of the single integument that eventually develops into a tough impenetrable covering that tightly encloses the embryo. The inner epidermis is delineated on the inside by a few layers of collapsed remnant endosperm cell wall layers and on the outside by remnant cell wall layers of zone 2, also called the middle layer. Together with the inner epidermis these remnant cell wall layers from collapsed cells may contribute towards seed coat impermeability. Zone 2 underneath the inner epidermis consists of large thin-walled parenchyma cells. Zone 3 is the sub-epidermal layers underneath the outer epidermis referred to as a hypodermis and zone 4 is the single outer seed coat epidermal layer. Both zones 3 and 4 develop unusual secondary wall thickenings. The primary cell walls of the outer epidermis and hypodermis disintegrated during the final stages of seed maturation, leaving only a scaffold of these secondary cell wall thickenings. In the mature seed coat the outer fibrillar seed coat consists of the outer epidermis and hypodermis and separates easily to reveal the dense, smooth inner epidermis of the seed coat. Outer epidermal and hypodermal wall thickenings develop over primary pit fields and arise from the deposition of secondary cell wall material in the form of alternative electron dense and electron lucent layers. ESEM studies showed that the outer epidermal and hypodermal seed coat layers are exceptionally hygroscopic. At 100% relative humidity within the ESEM chamber, drops of water readily condense on the seed surface and react in various ways with the seed coat components, resulting in the swelling and expansion of the wall thickenings. The flexible fibrous outer seed coat epidermis and hypodermis may enhance soil seed contact and retention of water, while the inner seed coat epidermis maintains structural and perhaps chemical seed dormancy due to the possible presence of inhibitors.     

Leaf structure and histochemistry of Ecballium elaterium (L.) A. Rich. (squirting cucumber)

Light, scanning and transmission electron microscopy as well as histochemical reactions were employed to study the leaf structure and secretory activity of Ecballium elaterium, a hairy pharmaceutical perennial common in the Mediterranean region. The amphistomatic leaf has a peculiar structure due to special cells supporting the conductive bundles, a remarkable shortage of mechanical tissue, and the existence of pectin strands between mesophyll cells. The secreting activity is limited mostly to secretary hairs. These attributes of the Ecballium leaf fine structures do not resemble the common structure of leaves from Mediterranean plants and point to a peculiar strategy of this species coping with stress conditions of its habitat.     

Influence of hydrodynamic forces on population structure of Pinna nobilis L., 1758 (Mollusca: Bivalvia): The critical combination of drag force, water depth, shell size and orientation

The effects of hydrodynamics on size, shape and distribution of benthic organisms are still not completely understood. Benthic organisms that inhabit wave-swept environments usually have small sizes and ethological adaptations to reduce drag and increase resistance force. Water speeds produced by waves in intertidal habitats can be more than 10 times higher than those in subtidal environments. However, comparatively small water speeds can produce high drag forces (F_d) on large subtidal organisms.Pinna nobilis is a subtidal epibenthic large bivalve-mollusc endemic to the Mediterranean Sea, a common inhabitant of Posidonia oceanica meadows. It lives partially buried in the seabed and shows a characteristic population structure. Small individuals are usually located at shallow sites whereas large individuals are only observed in deeper levels or sheltered locations. Also, some populations show a common orientation of the shell. These features are widespread throughout the Mediterranean, but their causes are unknown.The present work is a study on the relationship between population structure of P. nobilis and the habitat hydrodynamics. The main factor considered was Drag force due to the water flow produced by waves. Drag forces (F_d) supported by two populations located at different depths in the same P. oceanica meadow were estimated according to both the size and orientation of shells. Also, F_d acting on the individuals during the greatest storm recorded in the zone in the previous 9 years, were calculated. Drag coefficients (C_d), necessaries to estimate F_d, were estimated in the towing tank of the “Ecuela Técnica Superior de Ingenieros Navales (ETSIN)” of the Polytechnic University of Madrid.The results show significant differences in F_d acting in both populations. Despite the important increment of water speed with wave shoaling, individuals of the shallow population (SP), located at 6 m depth, withstand less F_d than those of the deep population (DP), at 13 m depth. The main reasons of this F_d reduction in SP are both the small size of the individuals and their common orientation, having the dorso-ventral side of the shell towards the main water flow. This fact, together with previous data showing higher mortality, less density of individuals, and less maximum asymptotic length, evidence that selective pressures regulate these population parameters, producing a trade-off between hydrodynamics, shell size and orientation, for each shore type and water depth.Combining the data of F_d supported by each population for different wave types, approximate values of the optimal mean F_d and the maximum dislodgement force withstood by P. nobilis were estimated (< 9 Newton (N) and ≈ 45 N respectively).     

Heat coma and its relationship to ocean dynamics in the oceanic sea skaters of Halobates (Heteroptera: Gerridae) inhabiting Indian and Pacific Oceans

This study was performed to clarify how weather and current dynamics affect the resistance to temperature change in the oceanic sea skaters, Halobates. Heat coma temperature (HCT) was measured for the adults and 5th instar larvae of four Halobates species collected from a fixed sampling location (12°00′N, 135°00′E ) in western tropical Pacific Ocean and from 13 locations in the eastern area of the India Ocean ranging from 08°00′N-06°00′S and 86°00-76°00′E. Both the gap temperature for heat coma (GTHC, mean±SD: 7.83±1.86 °C, n=32) and the heat coma temperature (HCP, 35.03±1.80 °C, n=32) of individuals collected from the Pacific Ocean, during the first half (10 days) of the sampling period at the fixed sampling point, were significantly higher than those during the second half (GTHC: 5.10±2.05 °C, n=63; HCP: 34.03±2.02 °C, n=63). The reduction in heat tolerance shown in the second half of the 20 day period may have been caused by a decrease in air temperature due to rainfall that occurred around the sampling point accompanied with the arrival of Typhoon No. 6.In the study of individuals collected from the Indian Ocean, significantly higher average GTHCs of >8 °C were recorded for the adult H. micans collected at 02°00′S and 06°00′S (89°00′E) than those at 0°00-8°00′N in the eastern Indian Ocean. Dynamic mixture of water from northern and southern currents occurs at 02°00-6°00′S of the Indian Ocean and might relate to such high heat tolerance.Temperature dynamics in the ocean habitat might directly affect the temperature resistance of the oceanic sea skaters.     

Embryo structure,seed traits,and productivity of relict vine Aristolochia contorta (Aristolochiaceae)

The herbaceous vine Aristolochia contorta (Aristolochiaceae) is a rare plant with a fragmented area in East Asia. Confocal laser-scanning microscopy and stereomicroscopy were employed to examine the seed and embryo structure. This is the first research on embryo anatomy in Aristolochia. Shape and structure of this embryo may be phylogenetically significant. The seed structure of A. contorta is similar to that of other Aristolochia species. Considerable variation is found for productivity traits; the average seed set is rather low (26.7%). The studied seed and embryo traits of A. contorta are found to be variable, but may be potentially informative at the genus and species level. The restricted productivity and reduced population size threaten the continued survival of A. contorta and, perhaps, the butterfly that depends on it.