Infraciliature, Morphogenesis and Life Cycle of Endosphaera terebrans (Suctoria, Tokophridae)

The morphology, infraciliature, and life cycle of Endosphaera terebrans , a suctorian endocommensal of peritrichs, have been studied with the aid of silver impregnation.
The life cycle of Endosphaera terebrans begins with infection of the host cell by a small larva. The swarmer has a pointed needle-like cellular projection and two rings of cilia. The swarmer penetrates the peritrich, loses the cilia, and then matures into an adult. The infraciliature of the adult form has four rows of barren kinetosomes that lack kinetodesmal fibers. By endogenous budding, a migratory larva is produced that leaves the host cell through the peristomial disc and that can infect other peritrichs.     

The Permanence of the Infraciliature in Suctoria: An Electronmicroscopic Study of Pattern Formation in Tokophrya infusionum*

SYNOPSIS. The adult Tokophrya infusionum does not possess cilia, but has 20–30 barren basal bodies arranged in 6 short rows adjacent to the contractile vacuole pore. During reproduction, which is by internal budding, the contractile vacuole sinks into the parent along with the invaginating membranes that form the embryo and the wall of the brood pouch. The 6 rows of basal bodies radiate away from the pore and elongate to form 5 long ciliary rows, that encircle the anterior half of the embryo, and 1 short row at the posterior end. The contractile vacuole pore, along with several barren basal bodies, remains in the parent when the embryo is completed. The pore rises to the surface when the embryo is born. New basal bodies are then formed in the parent to replace those which were incorporated into the embryo, and formation of another embryo may begin. The cilia of the embryo are partially resorbed 10 min after the start of metamorphosis, with depolymerization of the ciliary microtubules. Later, the cilia and most of the basal bodies disappear completely, except for a group of barren basal bodies near the embryo's contractile vacuole pore, which form 6 rows and serve as an anlage for the basal bodies and cilia that arise during embryogenesis. There is, therefore, an organized infraciliature in Suctoria throughout their life cycle, and a distinct continuity of basal bodies across the generations.     

Infraciliature and myoneme system of Campanella umbellaria (Protozoa, Ciliophora, Peritrichida)

The infraciliature and myoneme system of Campanella umbellaria were revealed using the protargol impregnation technique. The main characteristics of the infraciliature are the peristomial ciliary rows (haplokinety and polykineties), which make four and a half turns around the peristomial disc before plunging into the infundibulum, and the aboral infraciliature, which is made up of the aboral ciliary wreath (trochal band) and the scopula. The myoneme system is composed of: 1) longitudinal fibers, which include 60-84 (mean 72.3) short longitudinal fibers, 40-56 (mean 45.8) medium-length longitudinal fibers, and numerous long longitudinal fibers; and 2) circular fibers, which include 8-12 (mean 9.3) peristomial ring fibers, linking fibers, support fibers, and peristomial disc fibers. The various fibers in C. umbellaria are interconnected to form a single myoneme system that may act as a cell skeleton as well as providing the mechanism by which the zooid contracts and relaxes.     

Migratory life cycle of Ephemerella maculata (Traver, 1934) (Ephemerellidae)

In this paper, I describe for the first time the migratory life cycle of an univoltine mayfly, Ephemerella maculata (Traver, 1934 Traver, J.R. (1934), ‘New North American Species of Mayflies (Ephemerida)’, Journal of the Elisha Mitchell Scientific Society, 50(1/2), 189–254. [Google Scholar]), between mainstems and tributaries of stream networks in California. Ephemerella maculata nymphs grow in sunny open mainstems and then emerge. Female adults fly into adjacent shaded tributaries, oviposit eggs, and die. The eggs diapause over summer and hatch in the fall in tributaries; then small nymphs drift down back to the mainstem before the subsequent spring growing season. Isotope analyses validate the adult migrations from mainstem to tributaries.

?Field rearing experiments show that the abundant algae in sunny mainstems are important food for the growth of E. maculata nymphs. However, eggs survive and hatch equally well in mainstem and tributaries, therefore, the fitness advantage of their migration to tributaries remains unclear.     

Improving the environmental performance of bio-waste management with life cycle thinking (LCT) and life cycle assessment (LCA)

The International Journal of Life Cycle Assessment - Globally, many countries worldwide aim at increasing the environmental sustainability of waste management activities. Special attention is...     

The life cycle of Laodicea indica (Laodiceidae,Leptomedusae, Cnidaria)

The life cycle of Laodicea indica is described. In the Bismarck Sea this species shows a normal alternation of generations in the wet season; but in the dry season the cycle is contracted, and planulae give rise to gonothecae without formation of a hydroid colony. Medusae are liberated about 3 d after planula settlement. This life cycle pattern is previously unreported in hydromedusae. The possible adaptive value of such a life cycle and the evolution of polyp reduction in hydromedusan life cycles are discussed.     

Pleoanamorphic life cycle ofExophiala (Wangiella) dermatitidis

The anamorph life cycle of the black yeastExophiala (Wangiella) dermatitidis is described. The fungus is dimorphic, yeast cells being the prevalent form of propagation. The fungus is strongly hydrophilic, probably completing its anamorph life cycle in submersion. Adaptation to dry conditions is slow. Types of conidiogenesis comprise annellidic, phialidic and sympodial reproduction, in addition to isotropic development. Phialoconidia fail to germinate under the conditions tested, and thus may have a function other than dispersal. Sterile, multicellular bodies resembling aCapronia teleomorph are described.     

小绒泡菌生活史及其形态建成期显微结构的观察

在完成小绒泡菌Physcaum pusillum生活史的同时,观察了小绒泡菌P.pusillum生活史不同阶段显微结构的形成.生活史研究结果表明:小绒泡菌P.pusillum的孢子萌发方式为裂式,黏变形体具两根鞭毛,较短一根不易观察到,原质团类型为显型原质团,子实体形态建成过程约需12-13h.显微结构观察结果表明:石...     

Infraciliature and morphogenesis in three rumen Diplodinium ciliates, Diplodinium polygonale, Diplodinium leche, and Diplodinium nanum, observed by light microscopy

Infraciliature and morphogenesis of three rumen ophryoscolecid ciliates, Diplodinium polygonale Dogiel, 1925, Diplodinium leche Imai et al., 1992, and Diplodinium nanum Imai, 1988, are described from pyridinated silver carbonate-impregnated specimens. These three species have two polybrachykineties in the buccal area and a polybrachykinety in the dorsal ciliary zone. The vestibular polybrachykinety (VP) of D. polygonale and D. leche arises from the dorsal extremity of the adoral polybrachykinety (AP) as in Entodinium species, extending toward the left in D. polygonale and toward the left posterior in D. leche. The VP of D. nanum arises from the inner side of the AP, separate from its dorsal extremity, as in other Diplodinium species and extends toward the left posterior. These series of the polybrachykinety arrangements in D. polygonale, D. leche, and D. nanum can be regarded as transitional forms in the evolution of an Entodinium-like ancestor to Diplodinium. Morphogenesis of these three Diplodinium species is not different from that of other Diplodinium species.     

A checklist of epibiotic ciliates (Peritrichia and Suctoria) on the cladoceran crustaceans

Despite the growing awareness of the ecological importance of epibiont-host associations, detailed inventories for planktonic hosts are rare. Here, we provide an updated checklist of the peritrich and suctorian epibiont ciliates (Ciliophora) on the cladocerans (Crustacea: Cladocera). Thirty-nine species of peritrich ciliates (of which 34 are assigned to species) and three species of suctorian ciliates are found to be epibionts on the Cladocera. Fifty-eight cladoceran taxa are known to be hosts of the ciliate epibionts, 33 of these hosts (57%) are planktonic. Seven taxa were determined to the level of genus. Complete species designations were geographically biased (38 of 51 species) towards European sites, suggesting poor taxonomic knowledge beyond Europe. Also, the recently discovered continental endemism of cladoceran hosts could indicate that associated ciliates are more diverse than previously appreciated.     

The life cycle of Euclinostomum heterostomum (Rudolphi, 1809) (Trematoda: Clinostomatidae)

In small forest streams of West Nigeria the snail species Bulinus globosus was found to be the first intermediate host of a clinostomatid species which proved in successful infection experiments with the cichlid fish Tilapia zillii as second intermediate host to be Euclinostomum heterostomum (Rudolphi, 1809). Final hosts are herons. The morphology of the redia and the morphology and behaviour of the cercaria are described for the first time. The metacercaria which settles dorsal to the swim-bladder or in the kidney of the host fish requires more than two months (at tropical temperatures) for full development. Histological sections of the metacercaria revealed that its pharynx is provided with only few muscle fibres but surrounded by many myoblast-like cells, and the fact that the interior surface of this organ has a dense brush-like lining consisting of long microtriches. The pathology of infected fish is briefly described, and remarks about the geographical distribution of the parasite are given.     

Apeironpro, software for life cycle assessment (LCA) and environmental performance evaluation (EPE)

Background, Aims and Scope  In the world there are more than thirty LCA software products, but they do not have inventories or an evaluation method either with regional applicability, especially for Colombia. A special software for Life Cycle Assessment and the Environmental Performance Evaluation has been developed, which considers the environmental impacts generated by products during their life cycle and processes involving productive activities. It accounts with inventories applicable to Colombia, for processes and services like electrical energy production, transport and waste disposition. The Ecoscarcity evaluation method was adapted to Colombia with national legislation and agreements for polluting reduction signed by country and the EPI (Environmental Points of Impact) was established for 353 substances. Methods  The software allows users to use the methodology which corresponds to the standard ISO 14030 and 14040 directives. The database uses the SPOLD international format. For ApeironPro software, database information used from monitoring air emissions and effluents on factories in the region were realized by the Environmental Research Group from Pontificia Bolivariana University and secondary type information has been obtained starting from studies realized by environmental organizations and factories in the country which are interested in the management of quality environmental indicators. The antiquity of the information was restricted from the last 5 years, 1998 to 2003, in order to possess temporal representativity. The Ecoscarcity method uses information of the Environmental Ministry and Environmental Institutes of Colombia for the actual current load (F), and target norm for total load (F_k), using information with national legislation and agreements for polluting reduction signed by the respective countries. The software was designed in Web ambience with the database in MySQL, while the programming language was JAVA from Sun Microsystem. Results  The software has inventories for energy (electricity from coal, natural gas, fuel oil, hydroelectricity) transport (mean air, truck, motor bus), processes (plastics, rubber, sugar, paints production, detergent production, combustion in heaters, foundry of copper, iron, gold), waste disposal (incineration and landfill). Discussion  The Ecoscarcity method was analyzed for seven impact categories: climate change, acidification, stratospheric ozone depletion, photo-oxidant formation, eutrophication, ecotoxicity and depletion of abiotic resources (coal, oil, natural gas, copper, nickel). Conclusions  For Colombia, the highest environmental impact is associated with the ozone layer depletion (235.7 Ecopoints/g) while the lowest is associated with depletion of coal (8.6 × 10⁻⁷ Ecopoints/g), although this is reasonable since Colombia is the tenth largest producer of coal in the world. Recommendations and Perspectives  Latin America and Colombia need more inventories for their processes and to identify the more significant environmental impacts of their industries. This work is an initial step in the research about Life Cycle Assessment and can also improve the work in ecolabels for Colombia.     

Heteroecious life cycle of two graminicolouspuccinia (Uredinales)

Puccinia erythropus, whose uredinial-telial stage occurs onMiscanthus andEularia spp. (Gramineae), was found to have a heteroecious macrocyclic life cycle with the spermogonial-aecial stage onCynanchum sublanceolatum var.obtusum (Asclepiadaceae).Puccinia miyoshiana, which forms the uredinial-telial stage onBothriochloa, Capillipedium, Eccoilopus, andSpodiopogon (Gramineae), is known to form its spermogonial-aecial stage onBuplerum spp. (Umbelliferae). By field observations and artificial inoculations,Bupleurum komarovianum was proved to serve as an additional spermgonial-aecial host of this fungus.     

Fenology and life cycle of Gracilariopsis tenuifions (Gracilariaceae) at Sucre, Venezuela

The aim of this work was to determine the frequency of different reproductive phases and to induce the germination of spores from tetrasporic and cystocarpic Gracilariopsis tenuifrons from Chacopata and La Pe?a, Venezuela, under controlled laboratory conditions (temperature 22 +/- 1 degree C, 12L:12D photoperiod, salinity of 36 +/-1 PSU and irradiance of 269 microE m(-2) s(-1)). Tetrasporic individuals dominated numerically over gametophitic individuals. The proportion of vegetative algae was very low. Only cystocarpic algae were collected and the spermatangia were absent. Sporulation, germination and formation of algae suggest that they present a Polysiphonia-type life cycle. Algae with reproductive structures were not obtained in the laboratory,