scholarly journals Oviposition behavior and host records for the parasitic midge Trichochilus lacteipennis (Johannsen) (Chironomidae: Orthocladiinae)

2018 ◽  
pp. 37-42
Author(s):  
David Harley Funk ◽  
Sherman Roberts ◽  
Alan Graham
Keyword(s):  
Larval Development ◽  
Adult Female ◽  
Water Surface ◽  
Oviposition Behavior ◽  
Long Strings ◽  
Larval Life ◽  
Free Living ◽  
Elliptio Complanata ◽  
Mussel Species

Adult female Trichochilus lacteipennis were observed to extrude long strings of eggs (up to 15 cm) in flight over a lake in Maine, USA. Once extruded females dropped to the water surface and released the strings. Larvae of T. lacteipennis are parasitic on Elliptio complanata at this site and probably additional unionid mussel species elsewhere. Based on our dissections of parasitized mussels and previous reports, it appears T. lacteipennis spend all or nearly all of their larval life within their mussel host, with first instars initially free-living inside the mantle. At some point larvae enter the marsupium and complete larval development on a diet of mussel eggs and/or glochidia before pupating within the marsupium. 

V - The development of Haliotis Tuberculata , with special reference to organogenesis during torsion

1937 ◽  
Vol 228 (552) ◽  
pp. 219-268 ◽  
Keyword(s):  
Nervous System ◽  
Special Reference ◽  
Larval Development ◽  
Retractor Muscle ◽  
Larval Life ◽  
Free Living ◽  
Larval Stages ◽  
Haliotis Tuberculata ◽  
New Interpretation ◽  
Selection Of

Investigation of the development of Haliotis tuberculata , Linnaeus, was undertaken as a natural sequel to an examination of the bionomics and anatomy of Haliotis (Crofts 1929, p. 159). It is an attempt to elucidate the organogenesis during the changing larval habits, in the hope of adding to the scanty ontogenetical evidence available towards solving the problems of gastropod evolution. Excellent accounts of the embryonic phase, including patiently worked out details of the cleavage and of gastrulation, have been published for Crepidula (Conklin 1897), Patella (Patten 1886; Wilson 1904; and Smith 1935), Trochus (Robert 1902), Physa (Wierzejski 1905), Dentalium (Wilson 1904). The only comprehensive accounts of gastropod larval development already published are of Paludina (Erlanger 1891; Tonniges 1896; Drummond 1902; Andersen 1924) and of Patella (Patten 1886; Smith I935). The accounts of Paludina elucidate the details of development of the coelom and its derivatives. The viviparous habit and consequent loss of free larval life in Paludina , however, make it a very unsuitable example of gastropod development. Evolutionary stages are more likely to be traced from the development of less specialized gastropods, an adequate selection of whose free-living larval stages can be obtained. The larval development of Patel, Acmaea, Trochus and Haliotis has been described, in varying completeness for the different genera. Patten’s work on Patella coerulea (1886) gives a description only of the beginning of organogenesis. After a lapse of fifty years a more detailed account of the development of P. vulgata has been given by Smith (1935). This work gives a new interpretation of the development of the mesoderm, of the muscles and of the nervous system. The dorsal retractor muscle of the larva, which Patten indicated for P. coerula , is shown in P. vulgata to be placed asymmetrically and torsion takes place “ under the action” of this muscle.

The missing links: larval and post-larval development of the ascoglossan opisthobranch Elysia viridis

2000 ◽  
Vol 80 (6) ◽  
pp. 1087-1094 ◽  
Author(s):  
Cynthia D. Trowbridge
Keyword(s):  
Larval Development ◽  
Growth Rates ◽  
Shell Length ◽  
Larval Growth ◽  
Model Organism ◽  
Larval Life ◽  
Codium Fragile ◽  
Planktotrophic Larvae ◽  
Algal Diet ◽  
Better Than

The stenophagous ascoglossan (=sacoglossan) opisthobranch Elysia viridis has long been a model organism for the study of endosymbiosis or kleptoplasty as well as one of the few herbivores to consume the introduced green macroalga Codium fragile on European shores. Larval and post-larval dynamics of the ascoglossan were investigated. Planktotrophic larvae of E. viridis grew at 5–10 μm d−1 (shell length) at 15°C on a unicellular algal diet (the cryptophyte Rhodomonas baltica); larvae became competent one month post-hatching. Effective feeding and chloroplast acquisition typically started within 2–3 d of metamorphosis. Slugs grew about 8 mm in the first month of post-larval life. During this period, juveniles held in the light did not grow faster or survive better than conspecifics held in the dark; thus, functional kleptoplasty did not occur during first three weeks of benthic life. While larval growth rates and the nature of metamorphic cues are consistent with those of many other opisthobranch species with planktotrophic larvae, measures of post-larval growth—particularly as it pertains to kleptoplasty—is a new contribution to opisthobranch biology.

Neurogenesis in the thoracic neuromeres of two crustaceans with different types of metamorphic development

1998 ◽  
Vol 201 (17) ◽  
pp. 2465-2479 ◽  
Author(s):  
S Harzsch ◽  
J Miller ◽  
J Benton ◽  
RR Dawirs ◽  
B Beltz
Keyword(s):  
Embryonic Development ◽  
Larval Development ◽  
Neuronal Development ◽  
Temporal Patterns ◽  
Homarus Americanus ◽  
Spider Crab ◽  
Larval Life ◽  
Larval Stages ◽  
Metamorphic Development ◽  
Embryonic And Larval Development

The mode of embryonic and larval development and the ethology of metamorphosis in the spider crab and the American lobster are very different, and we took advantage of this to compare neuronal development in the two species. The goals of this study were to discover whether the differences in the maturation of the neuromuscular system in the pereopods and the metamorphic changes of motor behavior between the two species are reflected at the level of the developing nervous system ('neurometamorphosis'). Furthermore, we wanted to broaden our understanding of the mechanisms that govern neuronal development in arthropods. Proliferation of neuronal stem cells in thoracic neuromeres 4-8 of the lobster Homarus americanus and the crab Hyas araneus was monitored over the course of embryonic and larval development using the in vivo incorporation of bromodeoxyuridine (BrdU). Neuropil structure was visualized using an antibody against Drosophila synapsin. While proliferation of neuronal precursors has ceased when embryogenesis is 80 % complete (E80%) in the lobster thoracic neuromeres, proliferation of neuroblasts in the crab persists throughout embryonic development and into larval life. The divergent temporal patterns of neurogenesis in the two crustacean species can be correlated with differences in larval life style and in the degree of maturation of the thoracic legs during metamorphic development. Several unusual aspects of neurogenesis reported here distinguish these crustaceans from other arthropods. Lobsters apparently lack a postembryonic period of proliferation in the thoracic neuromeres despite the metamorphic remodeling that takes place in the larval stages. In contrast, an increase in mitotic activity towards the end of embryonic development is found in crabs, and neuroblast proliferation persists throughout the process of hatching into the larval stages. In both E20% lobster embryos and mid-embryonic crabs, expression of engrailed was found in a corresponding set of neurons and putative glial cells at the posterior neuromere border, suggesting that these cells have acquired similar specific identities and might, therefore, be homologous. None of the BrdU-labeled neuroblasts (typically 6-8 per hemineuromere over a long period of embryogenesis) was positive for engrailed at this and subsequent stages. Our findings are discussed in relation to the spatial and temporal patterns of neurogenesis in insects.

scholarly journals Transfer of cadmium from ants to ant-lions

1995 ◽  
Vol 6 (2-3) ◽  
pp. 133-138 ◽  
Author(s):  
Pekka Nuorteva
Keyword(s):  
Larval Development ◽  
Food Chain ◽  
Important Food ◽  
Free Living ◽  
Food Items ◽  
Parallel Difference ◽  
Ant Lion ◽  
Formica Aquilonia ◽  
Sparse Population ◽  
Harmful Effects

Ants have been found to bear exceptionally high loads of Cd and other metals, but are in general quite resistant to the toxic effects of Cd. Possible harmful effects caused to their predators by high Cd content have not been studied. Detection of a sparse population of ant-lions on a beach at Padva in Bromarv, offered the possibility to make some preliminary observations of such harmfull effects. AAS-analyses showed that free-living ant-lion larvae bear a Cd load of 4.5 ppm/dwt in young larvae, 8.5 ppm in old ones. This corresponded approximately to the level occurring in their most important food items in Padva (4.5 ppm mean for workers of Formica rufibarbis Fabricius and 6.1 ppm for foragers of F. fusca Linnaeus). The level of Cd in the single ant-lion imago caught (0.5 ppm) was clearly lower than in larvae. Among the Cdantagonistic metals, Cu showed levels in ant-lions two- or three-fold those found in ants, whereas no parallel difference existed for Zn levels. During larval development the level of the essential Cu diminished to half whereas the level of Zn increased two-fold. The fate of surplus cadmium in the food chain was followed experimentally by feeding a forest-living colony of Formica aquilonia Yarrow with 0.5 kg honey containing 600 mg CdCl2 This elevated the Cd content of surface workers up to a level1 O-f old that considered normal, 90-100 ppm (n = 4), and of the inside workers up to 5-fold, 36-61 ppm (n = 6). When surface workers were fed to ant-lion larvae ad libidum, larval Cd content rose in one week to the level of the food (87 ppm). When the feeding of ant-lion larvae was continued by feeding them inside workers for additional 4 weeks, these larvae showed a Cd level (49 ppm), similar to that of their food; then when the feeding had continued for 8 weeks, the level, however, rose to 120 ppm. All ant-lion larvae, including those with the highest Cd content, were fully active and showed no symptoms of disease. Artificial Cd-feeding had no clear effect on the Cu-levels in ants or ant-lions, but Zn responded by an increase from the natural level of 501-603 ppm to 560-1 200 ppm.

scholarly journals Accidentally catching of the catfish Lophiosilurus alexandri (Steindachner, 1876) larvae in aquariums with different colors

2019 ◽  
Vol 79 (4) ◽  
pp. 612-616
Author(s):  
M. M. Pedreira ◽  
D. C. Costa ◽  
M. Schorer
Keyword(s):  
Larval Development ◽  
Blue Light ◽  
High Mortality ◽  
Standard Length ◽  
Larval Life ◽  
Visual Ability ◽  
Final Development ◽  
Good Contrast

Abstract The aim of this study was to evaluate the effect of different colors in development and survival of catfish Lophiosilurus alexandri larvae, as well as over the visual ability of the handler. Larvae were placed in 5 L-aquariums at a density of 7 larvae L-1 , and aquariums had different colors, and were: green and blue (light colors); brown and black (dark colors). The final development; survival, total and standard length, weight and biomass of the larvae were similar in all colored aquaria. The highest mortality occurred during the first days after hatching, declining over the period, when it is observed the larval development, indicating that care should be necessary in the first few days. During cleaning handling, the accidental catch of larvae was higher in black aquariums. In the first days of life, due to the fragility of the larvae, it is possible to verify that between the second and third day occur the greatest mortalities. The number of accidentally captured larvae was lower than the mortality, suggesting that the high mortality in early larval life is not influenced by the handler management. The catfish L. alexandri larvae should be cultivated in aquariums that allow a good contrast between the larvae and the background, to avoid accidental capture of larvae by the handler. It is suggested to avoid the use of dark and black aquariums.

Effect of structurally related flavonoids from Zuccagnia punctata Cav. on Caenorhabditis elegans

2014 ◽  
Vol 60 (1) ◽  
Author(s):  
Romina E. D’Almeida ◽  
María R. Alberto ◽  
Phillip Morgan ◽  
Margaret Sedensky ◽  
María I. Isla
Keyword(s):  
Caenorhabditis Elegans ◽  
Larval Development ◽  
Free Living ◽  
Egg Hatching ◽  
C Elegans ◽  
Therapeutic Drugs ◽  
Aerial Parts ◽  
Free Living Nematode ◽  
Development Processes ◽  
Anthelmintic Effect

AbstractZuccagnia punctata Cav. (Fabaceae), commonly called jarilla macho or pus-pus, is being used in traditional medicine as an antiseptic, anti-inflammatory and to relieve muscle and bone pain. The aim of this work was to study the anthelmintic effects of three structurally related flavonoids present in aerial parts of Z. punctata Cav. The biological activity of the flavonoids 7-hydroxyflavanone (HF), 3,7-dihydroxyflavone (DHF) and 2´,4´-dihydroxychalcone (DHC) was examined in the free-living nematode Caenorhabditis elegans. Our results showed that among the assayed flavonoids, only DHC showed an anthelmintic effect and alteration of egg hatching and larval development processes in C. elegans. DHC was able to kill 50% of adult nematodes at a concentration of 17 μg/mL. The effect on larval development was observed after 48 h in the presence of 25 and 50 μg/mL DHC, where 33.4 and 73.4% of nematodes remained in the L3 stage or younger. New therapeutic drugs with good efficacy against drug-resistant nematodes are urgently needed. Therefore, DHC, a natural compound present in Z. punctata, is proposed as a potential anthelmintic drug.

scholarly journals Infestation of shore crab gills by a free-living mussel species

2017 ◽  
Vol 48 (2) ◽  
pp. 1241-1246 ◽  
Author(s):  
Rowan Poulter ◽  
P. Graham Oliver ◽  
Chris Hauton ◽  
Trystan Sanders ◽  
Benjamin J. Ciotti
Keyword(s):  
Shore Crab ◽  
Free Living ◽  
Mussel Species

The effect of temperature on the survival and infectivity of the free-living larvae of Nippostrongylus brasiliensis

Parasitology ◽  
1983 ◽  
Vol 86 (1) ◽  
pp. 105-118 ◽  
Author(s):  
O. Hindsbo
Keyword(s):  
Geographical Distribution ◽  
Adult Female ◽  
Storage Time ◽  
Normal Development ◽  
Effect Of Temperature ◽  
Nippostrongylus Brasiliensis ◽  
Free Living ◽  
Adult Females ◽  
Infectivity Rate ◽  
The Mean

SUMMARYThe development, survival and infectivity of larvae of Nippostrongylus brasiliensis at 10 and 21 °C have been studied. In cultures developed for 1 weekat21 °C but stored at either 10 or 21 °C the mean recovery of larvae in 1·5 h Baermann sediment (46% and 42% of total eggs, respectively) and their infectivity (66% and 70% day 8 p.i. recovery, respectively) at 4 weeks of cultivation were similar. However, at 20 weeks of cultivation only a few larvae survived storage at 21 °C (1·4%) and the survivors showed very low infectivity (4·1%), whereas larvae stored at 10 °C retained most of their survival and infectivity rates (41% and 44%, respectively). In cultures developed and stored at 10 °C a lower mean proportion (17%) of the eggs was recovered as larvae at 4 weeks of cultivation. The mean infectivity rate of these larvae increased from 4 to 12 weeks of cultivation (18 % and 42 %, respectively) but was reduced at 20 weeks of cultivation (27 %). An increased proportion of adult female worms was recovered from rats infected with larvae from cultures showing poor development or survival and the fecundity of the adult females decreased in all groups as the storage time of the cultures was increased. Eggs from low fecundity adult worms showed normal development of larvae. The relation between survival, temperature in the habitat and the geographical distribution of the larvae of N. brasiliensis is discussed.

scholarly journals Redescription of the African Chordodes albibarbatus Montgomery 1898, and description of Chordodes janovyi n. sp. (Gordiida, Nematomorpha) and its non-adult stages from Cameroon, Africa

Zootaxa ◽  
2010 ◽  
Vol 2631 (1) ◽  
pp. 36 ◽  
Author(s):  
MATTHEW G. BOLEK ◽  
ANDREAS SCHMIDT-RHAESA ◽  
BEN HANELT ◽  
DENNIS J. RICHARDSON
Keyword(s):  
Oviposition Behavior ◽  
Adult Life ◽  
Distinct Species ◽  
Molecular Data ◽  
Sexually Dimorphic ◽  
Free Living ◽  
Life Cycle Stages ◽  
Contrast Microscopy ◽  
Interference Contrast Microscopy ◽  
Holotype Male

We redescribe Chordodes albibarbatus Montgomery 1898 from the original holotype male and the originally described female specimen using Nomarski interference contrast microscopy. Our reinvestigation indicates that C. albibarbatus is sexually dimorphic and contains five types of areoles in the male and six types of areoles in the female. Our reinvestigation of C. albibarbatus indicates that it is a distinct species, and is most similar to the African Chordodes gariazzi Camerano 1902 and Chordodes heinzei Sciacchitano 1937, all of which share simple “blackberry”, bulging, tubercles, and thorn areoles. In addition, we describe adult free-living male and female Chordodes janovyi n. sp. collected from West Province, Cameroon, Africa using both morphological (light and scanning electron microscopy) and molecular data, and designate types for this species. Chordodes janovyi belongs to a large group of Chordodes in which simple areoles are smooth or superficially structured less so than “blackberry” areoles. Present among the simple areoles are clusters of crowned and circumcluster areoles along with thorn and tubercle areoles, whereas bulging areoles are absent. We also describe the egg strings, eggs, larvae, cysts, and oviposition behavior of C. janovyi and compare these non-adult life stages to other nematomorph genera and species for which such life cycle stages are known, and we discuss the use of non-adult stages and the use of molecular tools in future studies of nematomorph systematics and biodiversity.

Sign in / Sign up

Export Citation Format

Share Document