scholarly journals Studies on the life history of the land-locked ayu Plecoglossus altivelis in Lake Ikeda. III. Embryonic Development and Morphological Changes with Growth of the Larval and Juvenile Ayu Plecoglossus altivelis of Lake Ikeda in Southern Kyushu.

1991 ◽  
Vol 57 (5) ◽  
pp. 789-795 ◽  
Author(s):  
Katsunori Tachihara ◽  
Seirô Kimura
Keyword(s):  
Life History ◽  
Embryonic Development ◽  
Morphological Changes ◽  
Plecoglossus Altivelis ◽  
History Of

THE LIFE HISTORY OF LESTES CONGENER (ODONATA: ZYGOPTERA) ON THE CANADIAN PRAIRIES

1974 ◽  
Vol 106 (4) ◽  
pp. 367-376 ◽  
Author(s):  
W. W. Sawchyn ◽  
C. Gillott
Keyword(s):  
Life History ◽  
Embryonic Development ◽  
Larval Development ◽  
Sexual Maturation ◽  
Low Temperatures ◽  
Canadian Prairies ◽  
History Of

AbstractLestes congener Hagen overwinters in the egg stage. There is a diapause just before blastokinesis, during which the egg is extremely resistant to low temperatures and desiccation. Post-diapause embryonic development can occur near 0 °C but will not take place until the eggs are wetted as the pond habitat fills in the spring. Hatching does not occur until the temperature exceeds about 5 °C and is highly synchronous. Larval development is rapid and is completed in the field in about 50 days. Emergence of the adults also is synchronous. Sexual maturation requires 3 weeks. Oviposition occurs immediately after copulation while the pair are still in tandem. It takes place only in dry stems of Scirpus. Adaptations of L. congener for life under rigorous prairie conditions are discussed.

The Development and Life History of Echinorhynchus truttae Schrank, 1788 (Acanthocephala)

1966 ◽  
Vol 40 (1-2) ◽  
pp. 11-32 ◽  
Author(s):  
J. B. E. Awachie
Keyword(s):  
Life History ◽  
Embryonic Development ◽  
Intermediate Host ◽  
Definitive Host ◽  
Room Temperature ◽  
Final Host ◽  
Gammarus Pulex ◽  
Pyloric Region ◽  
History Of ◽  
Sexually Mature

The details of the post-embryonic development of Echinorhynchus truttae in the intermediate host, Gammarus pulex, and the final host, Salmo truttae, are described.The cystacanths of this species are sexually mature and are formed about 82 days after infection at room temperature, ca. 17°C.Copulation takes place in the definitive host soon after the worms enter the pyloric region of the intestine. About 10 weeks after infection, mature eggs are passed out with the faeces of fish.

Observations on the Life History of Onthophagous depressus (Coleoptera: Scarabaeidae)

1996 ◽  
Vol 31 (1) ◽  
pp. 63-71
Author(s):  
J. S. Hunter ◽  
G. T. Fincher ◽  
D. C. Sheppard
Keyword(s):  
Life History ◽  
Embryonic Development ◽  
Pupal Stage ◽  
Soil Surface ◽  
Cattle Dung ◽  
Brood Cell ◽  
Pupal Development ◽  
Adult Females ◽  
History Of ◽  
Southern Georgia

Adult Onthophagus depressus Harold constructed brood cells of cattle dung 15 to 30 cm below the soil surface. These brood cells averaged 23.1 mm long and 16.1 mm wide. Adult females deposited a single egg in the egg chamber of each brood cell. Eggs were 2.3 to 2.5 mm long and 1.1 to 1.4 mm wide. Embryonic development required 2.5 to 4.3 d; larval development (three instars) 27 d, and pupal development about 12 d. Development from egg to adult averaged 46.3 d at 25–27°C. Adult beetles were captured in all months except February with peak flight activity between 2000 and 2100 h (EST). Overwintering occurred in the adult and/or pupal stage in southern Georgia.

Bet hedging and cold-temperature termination of diapause in the life history of the Atlantic salmon ectoparasite Argulus canadensis

Parasitology ◽  
2020 ◽  
Vol 147 (14) ◽  
pp. 1774-1785
Author(s):  
Tyler J. Lynn ◽  
Ji-Won Jeong ◽  
Michael S. Duffy
Keyword(s):  
Life History ◽  
Embryonic Development ◽  
Atlantic Salmon ◽  
Salinity Tolerance ◽  
Cold Treatment ◽  
Cold Temperature ◽  
Bet Hedging ◽  
Egg Diapause ◽  
Egg Storage ◽  
History Of

AbstractArgulus canadensis is a crustacean ectoparasite observed increasingly on wild migrating adult Atlantic salmon. We investigated temperature and salinity tolerance regarding development, survival and hatch of A. canadensis eggs to help understand spatiotemporal features of transmission. Argulus canadensis eggs differentiate to pharate embryos by 35 days buttheir hatch is protracted to ~7 months. Cold treatment ⩾75 days mimics overwintering and terminates egg diapause, with 84.6% (72.1–100%) metanauplius hatch induced ⩾13 °C and synchronized to 3–4 weeks. Inter- and intra-clutch variability and protracted hatch in the absence of cold-temperature termination of diapause is compatible with bet hedging. Whereas diapause likely promotes phenological synchrony for host colocalization, bet hedging could afford temporal plasticity to promote host encounter during environmental change. Our egg storage and hatch induction/synchronization methodologies can be exploited for empirical investigations. Salinity tolerance reveals both significantly higher embryonic development (94.4 ± 3.5% vs 61.7 ± 24.6%) and metanauplius hatch (53.3 ± 7.5% vs 10.1 ± 8.2%) for eggs in freshwater than at 17 ppt. Unhatched embryos were alive in freshwater by the end of the trial (213 days) but were dead/dying at 17 ppt. Eggs did not develop at 34 ppt. Salinity tolerance of A. canadensis eggs supports riverine transmission to adult Atlantic salmon during return to freshwater for mating each year.

Sign in / Sign up

Export Citation Format

Share Document