scholarly journals Annual life cycle of the spider mite, Eotetranychus dissectus EHARA (Acarina: Tetranychidae) on mono maple.

1988 ◽  
Vol 32 (3) ◽  
pp. 219-223 ◽  
Author(s):  
Tetsuo GOTOH
Keyword(s):  
Life Cycle ◽  
Spider Mite ◽  
Annual Life Cycle

Temporal variation in the weight-size relationship of the mangrove crab Ucides cordatus L. (Decapoda: Ucididae) in relation to its life cycle phases

2014 ◽  
Vol 64 (4) ◽  
pp. 333-342 ◽  
Author(s):  
Marcos de Miranda Leão Leite ◽  
Cynthia Yuri Ogawa ◽  
Carla Ferreira Rezende ◽  
José Roberto Feitosa Silva
Keyword(s):  
Life Cycle ◽  
Condition Factor ◽  
River Estuary ◽  
Total Weight ◽  
Northeastern Brazil ◽  
Annual Life Cycle ◽  
Ucides Cordatus ◽  
Mangrove Crab ◽  
Significant Difference ◽  
The Relationship

The relationship between weight and size of individuals can be used to evaluate the status of a population, which is particularly useful for natural populations that are being exploited. Ucides cordatus occurs on the Atlantic coast of the American continent, from Florida (USA) to Santa Catarina (Brazil). This species is economically very important, most of all in the Northeastern area of Brazil, as well as in the Dominican Republic and Suriname. The objective of this study was to analyze life phases (‘fattening’, ‘matumba’, ‘milk-crab’, ‘maturation’ and ‘walking’) by use of the weight-length relationships, as well as temporal variations in this condition factor for each sex of U. cordatus. For this purpose, individuals were sampled monthly for twenty-four months at the Jaguaribe River estuary, Ceará State, Northeastern Brazil. The relationship between total weight and cephalothorax width was established using regression analysis, adjusted by a power equation. The dynamics of the condition factor were analyzed for each sex using the variation of its averages related to annual life cycle; this was done for each of the previously-mentioned phases. The relationship between total weight and cephalothorax width showed an isometric growth in males and negative allometric growth in females suggesting that, for the same reference size, males are heavier than females. When considering the average of the female condition factors, these were greater than those for males during the annual life cycle, except during the ‘maturation’ phase, which is the phase with a higher demand of energetic reserves for males. Annual variation of the condition factor in females presented no significant difference.

Changes in migration, carry-over effects, and migratory connectivity

2019 ◽  
pp. 93-107 ◽  
Author(s):  
Roberto Ambrosini ◽  
Andrea Romano ◽  
Nicola Saino
Keyword(s):  
Climate Change ◽  
Life Cycle ◽  
Population Size ◽  
Migratory Connectivity ◽  
Negative Effects ◽  
Annual Life Cycle ◽  
Northern Latitudes ◽  
Timing Of Migration ◽  
Tropical Areas ◽  
Carry Over

Studies of the timing (phenology) of bird migration provided some of the first evidence for the effects of climate change on organisms. Since the rate of climate change is uneven across the globe, with northern latitudes experiencing faster warming trends than tropical areas, animals moving across latitudes are subject to diverging trends of climate change at different stages of their annual life cycle, and, consequently, they can become mistimed with the local ecological conditions, with potentially negative effects on population size. This chapter reviews the modifications induced by climate change in different migration traits, like the timing of migration events, the distribution of organisms, and the direction and the speed of movements. It also considers the effects of ecological carry-over effects and migratory connectivity on the response of birds to climate change.

A taxonomic review of the Margarodoid genus Stigmacoccus Hempel  (Hemiptera: Sternorrhyncha: Coccoidea: Stigmacoccidae), with some details on their biology

Zootaxa ◽  
2007 ◽  
Vol 1507 (1) ◽  
pp. 1-55 ◽  
Author(s):  
CHRIS HODGSON ◽  
HEATHER GAMPER ◽  
AMAURI BOGO ◽  
GILLIAN WATSON
Keyword(s):  
Life Cycle ◽  
Scale Insect ◽  
Present Knowledge ◽  
Passerine Birds ◽  
Adult Males ◽  
Undescribed Species ◽  
Annual Life Cycle ◽  
Honey Production ◽  
Adult Females ◽  
The Family

Stigmacoccus is an unusual scale insect genus from Central and South America that has been little studied. It belongs to the family Stigmacoccidae within the archaeococcoid group of genera which used to comprise the family Margarodidae (Morrison, 1927) but which are now considered to represent at least 9 families. The present paper describes or redescribes the adult females, adult males, cyst stages and crawlers of the three known species (S. asper, S. garmilleri, and S. paranaensis), plus the prepupa of S. garmilleri and S. paranaensis, and (briefly), the pupa of S. paranaensis. It is considered that the female has two cyst stage instars; the number in the male is uncertain. Adult female S. asper and S. paranaensis appear to have groups of loculate pores on the walls of the vagina. A lectotype for S. asper is designated. In addition, cyst stages of three further undescribed species are described (but not formally named) and illustrated. Some observations on the biology and life cycle are also included. The honeydew of Stigmacoccus species has been shown to be an important energy source for overwintering passerine birds which defend this resource. A summary of our present knowledge is presented, including how the honedew is eliminated (through a long anal tube) and details are given with regard to rates of honeydew flow, sugar concentration, cyst densities and annual timing of peak flows. The annual life cycle, as far as it is known, is discussed. It is concluded that this honeydew could be economically important as a source of sugar for honey production but this would need to be carefully managed to maintain an ecological balance.

Long-term effects of 2,4-D application on plants. II. Herbicide avoidance by Chenopodium album and Thlaspi arvense

1988 ◽  
Vol 66 (2) ◽  
pp. 230-235 ◽  
Author(s):  
Larry Hume
Keyword(s):  
Life Cycle ◽  
Chenopodium Album ◽  
Herbicide Tolerance ◽  
Long Term Effects ◽  
Annual Life Cycle ◽  
Thlaspi Arvense ◽  
Immature Seeds ◽  
Winter Annual ◽  
Dichlorophenoxy Acetic Acid

Research plots in a wheat–wheat–fallow rotation at Indian Head, Sask., were sprayed annually with 2,4-dichlorophenoxy-acetic acid (2,4-D) for 36 consecutive years. Two species susceptible to 2,4-D, Chenopodium album L. and Thlaspi arvense L., were dominant in these plots. From 1981 to 1983, C. album and T. arvense seedlings that emerged during four periods of the growing season were marked and their mortality, seed production, and size recorded. From these data and other studies, 10 ways in which C. album and T. arvense managed to survive herbicide application were identified. These are intermittent germination, herbicide tolerance, small size of late-emerging seedlings, short life cycle, hardiness, failure of control practices, long-term dormancy, seed dispersal, viability of immature seeds, and winter annual life cycle of T. arvense.

Field and laboratory studies on the life-cycle, growth and feeding preference in the hairy snail Trochulus hispidus (L., 1758) (Gastropoda: Pulmonata: Hygromiidae)

Biologia ◽  
2013 ◽  
Vol 68 (1) ◽  
Author(s):  
Małgorzata Proćków ◽  
Magda Drvotová ◽  
Lucie Juřičková ◽  
Elżbieta Kuźnik-Kowalska
Keyword(s):  
Life Cycle ◽  
Food Preferences ◽  
Land Snail ◽  
Feeding Preference ◽  
Early Spring ◽  
Reproductive Period ◽  
Acer Pseudoplatanus ◽  
Annual Life Cycle ◽  
Cycle Growth ◽  
In The Wild

AbstractFor the first time the life cycle of the common land snail Trochulus hispidus was completely described in Central Europe (Poland). This is a semelparous species predominantly with an annual life cycle and the reproductive period lasting from April till October. The first young snails hatch in spring, grow rapidly in summer and reach ca. 4 whorls until winter. In spring of the next year they mature and reproduce. After that they die. There is hardly any growth from late autumn till early spring. The average proportional growth rate is ca. 0.3 whorl/month in the wild. The fastest growth is present in the youngest snails and then gradually decreases over the course of their age. Laboratory and field observations allowed for establishing the following life cycle parameters: eggs calcified, almost spherical, ca. 1.5 mm, laid in spring and summer in batches of between 1 and 47. Time to hatching is 6–24 days, hatching is asynchronous; newly-hatched snails have approximately 1.5 whorls. Analysis of food preferences revealed, that T. hispidus tends to restrict its diet during the life. Generally the youngest snails equally consumed leaves of all four tree species offered (Fraxinus excelsior, Acer pseudoplatanus, Tilia cordata and A. platanoides) whereas adults preferred F. excelsior over A. pseudoplatanus and A. platanoides.

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