scholarly journals The Biology and Behaviour of Ptinus Tectus Bole. (Coleoptera, Ptinidae), A Pest of Stored Products

1942 ◽  
Vol 18 (3) ◽  
pp. 290-305
Author(s):  
D. W. EWER ◽  
R. F. EWER
Keyword(s):  
Developmental Stages ◽  
Free Water ◽  
Egg Laying ◽  
Temperate Climate ◽  
Larval Feeding ◽  
Stored Products ◽  
Not Given ◽  
Complete Development ◽  
Low Humidity ◽  
Eggs And Larvae

At 70% R.H. development of Ptinus tectus from egg laying to emergence from the cocoon is minimal at 23-25°C. and takes an average of about 62 days; at 15°C. the time taken is about 130 days. The minimum temperature at which complete development can occur is below 10°C. and the maximum is between 28 and 30°C.; considerable mortality occurs in eggs and larvae at 28°C. and the eggs require a humidity of 100% R.H. for hatching at this temperature. At 75% R.H. and above it is difficult to prevent moulds growing on the food of Ptinus. It appears that 70% R.H. is a satisfactory humidity for all developmental stages, but in air drier than this (at 25°C.) both eggs and larvae show an increased mortality and a prolonged development. The hatching of the egg, rather than embryonic development, seems to be sensitive to low humidity. Adults given food but not water live longer at 70% R.H. (27°C.) and at 90% R.H. (15°C.) than at lower humidities. At 25°C., below 70% R.H. feeding is much reduced if water to drink is not given; at 34% there is little feeding even when free water is available. Larval feeding is also reduced at low humidities. Oviposition soon ceases unless drinking water is available, at any rate at low humidities. Ptinus tectus is thus adapted to a temperate climate with a high humidity.

Laboratory Colonisation of the Mosquito, Eretmapodites chrysogaster Grah

1958 ◽  
Vol 49 (2) ◽  
pp. 287-290 ◽  
Author(s):  
J. D. Gillett
Keyword(s):  
Blood Meal ◽  
Free Water ◽  
Sensu Stricto ◽  
Egg Laying ◽  
Cotton Wool ◽  
Female Mosquito ◽  
Male Progeny ◽  
Single Batch

SummaryA colony of Eretmapodites chrysogaster Grah., sensu stricto, was maintained successfully for over a year without any reinforcement.Identity of the mosquitos was established by starting the colony from a single batch of eggs laid by a single wild-caught female mosquito, and subsequent examination of the genitalia of the male progeny.Mating occurred regularly after the first blood-meal of the female. In fact the females would not accept the males until they had started, or had finished, their first blood-meal.Eggs were laid on the sterilised, water-filled bracts of banana flowers. Moist paper, moist cotton-wool or free water above paper or cotton-wool proved unsatisfactory as egg-laying media.Larvae fed largely on the substance of the banana bracts on which the eggs had been laid. The banana bract also provided cover and so reduced the incidence of cannibalism among larvae.

scholarly journals Intertidal life: field observations on the clingfish Gobiesox barbatulus in southeastern Brazil

2011 ◽  
Vol 9 (1) ◽  
pp. 233-240 ◽  
Author(s):  
Tiago H. S Pires ◽  
Fernando Z Gibran
Keyword(s):  
Developmental Stages ◽  
Feeding Activity ◽  
Single Layer ◽  
Egg Laying ◽  
Reproductive Season ◽  
Feeding Habit ◽  
Southeastern Brazil ◽  
Field Observations ◽  
Nocturnal Feeding ◽  
Particulate Feeding

The clingfish Gobiesox barbatulus shows nocturnal feeding activity, spending most part of the day stationary and adhered to the inferior part of stones. To feed, this species uses the sit-and-wait and particulate feeding tactics. It shows a carnivorous feeding habit mostly consuming small benthic crustaceans. It can move in two ways: (1) "stone-by-stone", sliding its ventral sucker disc across each stone and (2) "surf", when it takes advantage of the energy of the ebbing tide to quickly cross a distance up to four times its body length. Its reproductive season occurs between the end of spring and the beginning of summer, during which time it lays about 2,000 adhesive eggs of 1 mm each in a single layer under stones. It has more than one egg-laying session per reproductive season, therefore showing several different developmental stages. It performs fanning, mouthing and guarding of the eggs as forms of parental care. Data shown here also indicates that G. barbatulus has some shelter fidelity, being probably territorial.

The morphology of the British Prostriata with particular reference to Ixodes hexagonus Leach. II

Parasitology ◽  
1953 ◽  
Vol 42 (3-4) ◽  
pp. 161-186 ◽  
Author(s):  
D. R. Arthur
Keyword(s):  
Developmental Stages ◽  
Egg Laying ◽  
The Body ◽  
Dorsal Margin ◽  
Leg Length ◽  
Large Size ◽  
Attachment Sites ◽  
Wide Range ◽  
Primitive Condition ◽  
Basis Capituli

The palps of all stages of Ixodes trianguliceps are provided with a ventral plate below the basal article; formerly this plate was thought to be the first palpal article. This article in the larva and nymph is produced forward into a spur, but in the female tick this spur is incorporated into the basis capituli as the sella. The hypostomes of I. trianguliceps and I. canisuga are redescribed to clear up existing inaccuracies.Ticks in which the rostrum does not extend beyond the apex of the first palpal article are found on birds, and this probably represents a primitive condition. Those with palpal spurs, which may or may not be fused with the basis capituli, are found on birds (not in Britain) or on mammals of the mouse size group, and those where the rostrum is produced beyond the first palpal article occur on a wide range of large and small animals. The longer and more heavily toothed digits of ticks appear to be associated with a wide host range and vice versa. The structure of the digit may also influence the choice of attachment sites by ticks on their hosts because the microstructure of the skin varies in different parts.Variations in size and form of the scuta of some British ticks are described, and the mean growth rate is ascertained from this data. The information shows that the material of I. ricinus and I. hexagonus is homogeneous, and that specific differences occur in size, shape, the position and type of dermal ducts and in the relation between scutal and alloscutal bristles.The morphology of Gené's organ in I. hexagonus is described. It consists of a basal sac-like portion surmounted by four horns and lined with a cuticle beneath an epithelium. The gland is a proliferation of the epithelium and located near the bifurcation of the base into the horns. A watery refractile fluid, secreted by the gland, accumulates between the epidermis and the cuticle in the horn-like extensions. Proximally the thick endocuticle and epidermis lie close together, and two cuticularized rods penetrate the endocuticle for about half-way along the stalk. The rods arise from the postero-dorsal margin of the basis capituli. Muscles, arising from the free ends of the rods, pass back to near the hind-margin of the scutum; they retract the basis capituli after egg laying and indirectly assist in the retraction of Gené's organ. A suggested mechanism for everting Gené's organ in I. hexagonus is outlined.During feeding the opisthosomatic cuticle of all developmental stages of the tick is much stretched. In the larva, where the cuticle is thin, this is effected by the flattening of the epicuticular pleats, but nymphs and females have, in addition, two longitudinal folds alongside the body which stretch to a far greater extent than do the epicuticular pleats. Similar folds are present between the hard ventral plates and the scutum and between the epimeral and median plates in the male. Coupled with the large size of the male digit, this suggests that morphologically, at least, males can imbibe blood.The growth of the leg segments of I. hexagonus is not constant from stage to stage, and as a result the shortest ‘leg-length’ of the female exceeds the longest ‘leg-length’ of the male.

scholarly journals Species identification of Anguilla japonica by real-time PCR based on a sequence detection system: a practical application to eggs and larvae

2009 ◽  
Vol 66 (9) ◽  
pp. 1915-1918 ◽  
Author(s):  
Yuki Minegishi ◽  
Tatsuki Yoshinaga ◽  
Jun Aoyama ◽  
Katsumi Tsukamoto
Keyword(s):  
Real Time ◽  
Species Identification ◽  
Developmental Stages ◽  
Detection System ◽  
Anguilla Japonica ◽  
Sequence Detection ◽  
Target Region ◽  
System A ◽  
Sequence Variations ◽  
Eggs And Larvae

Abstract Minegishi, Y., Yoshinaga, T., Aoyama, J., and Tsukamoto, K. 2009. Species identification of Anguilla japonica by real-time PCR based on a sequence detection system: a practical application to eggs and larvae. – ICES Journal of Marine Science, 66: 1915–1918. To develop a practical method for identifying Japanese eel Anguilla japonica eggs and larvae to species by a sequence detection system using a real-time polymerase chain reaction (PCR), we examined (i) the sensitivity of the system using samples at various developmental stages, and (ii) influences of intra- and interspecific DNA sequence variations in the PCR target region. PCR amplifications with extracted DNA solution at 7.0 ng µl−1 or lower were efficient at distinguishing A. japonica from other anguillids. A single egg at the gastrula or later developmental stages could also be identified. Two sequence variations in the PCR target region were observed in 2 out of 35 A. japonica collected from three localities, and from four year classes at a single locality. These mutations, however, did not affect the result of species identification achieved by A. japonica-specific PCR primers and probe. The accuracy of this PCR-based method of species identification will help in field surveys of the species.

Relative Roles of Blow Flies (Diptera: Calliphoridae) and Invasive Fire Ants (Hymenoptera: Formicidae: Solenopsis spp.) in Carrion Decomposition

2021 ◽  
Author(s):  
Grant D De Jong ◽  
Florencia Meyer ◽  
Jerome Goddard
Keyword(s):  
Southeastern United States ◽  
Fire Ants ◽  
Decomposition Rates ◽  
Ecological Processes ◽  
Blow Flies ◽  
Complete Development ◽  
Eggs And Larvae ◽  
Entomological Data ◽  
Carrion Decomposition

Abstract Fire ants (Solenopsis spp.) have increasingly been reported from carrion in the southeastern United States and are now a part of the normal succession community. There have been previous observations of these ants altering carrion and preying on other carrion-attendant fauna; however, the overall effects of these activities on carrion decomposition rates, community composition, and blow fly larval development are poorly understood. Alteration of these ecological processes by fire ants could affect the forensic interpretation of entomological data. We conducted a study in Mississippi and Florida whereby portions of the succession fauna were excluded from access to pig carrion to study the relative effects of fire ants and blow flies on carrion decomposition and succession: a control with all fauna having access, a second treatment where fire ants and other geophilic taxa were excluded, and a third treatment in which blow flies and other large organisms were excluded. Fire ants inflicted lesions in the carrion, buried portions that touched the ground, and preyed on some members of the succession fauna. Their exclusion did not affect carrion decomposition rates that were measured but slightly affected the overall carrion community, and strongly affected the oviposition and development of blow flies. Despite the presence of fire ants early in the control, blow flies were eventually able to overcome predation of eggs and larvae, continue colonization, and complete development; however, the delay in the colonization of blow flies on carrion could affect the determination of postmortem intervals when development rates of blow flies are considered in the calculation.

Reproductive strategy of Scyliorhinus canicula (L., 1758): a holistic approach based on macroscopic measurements and microscopic observations of the reproductive organs

2020 ◽  
Vol 71 (6) ◽  
pp. 596
Author(s):  
Vasiliki Kousteni ◽  
Persefoni Megalofonou
Keyword(s):  
Reproductive Tract ◽  
Developmental Stages ◽  
Population Decline ◽  
Holistic Approach ◽  
Reproductive Period ◽  
Egg Laying ◽  
Future Research ◽  
Maturity Stage ◽  
Population Modelling ◽  
Scyliorhinus Canicula

Understanding reproductive features of elasmobranchs that affect population recovery and natural mortality is essential for conservation management planning. Considering macroscopic and microscopic observations of the reproductive tract in 2253 individuals, sampled in Hellenic waters over a 7-year period, four reproductive stages were described. The presence of advanced spermatocyst stages in immature testes supported the early gamete development and long maturation process. The simultaneous presence of follicles of all developmental stages in mature ovaries indicated a protracted egg-laying season. An extended reproductive period was also supported by monthly records of egg-laying females, sexually active males, large egg cases and high values of the gonadosomatic (GSI) and hepatosomatic (HSI) indices. Size at maturity was similar for both sexes. Females and males exhibited no depth segregation compared with individuals of different maturity stages regardless of sex. Sex, size and maturity stage significantly affected GSI, HSI and the relative condition factor. All three somatic indices showed a similar monthly variation, supporting a fat assimilation rate that follows maturation rate, with both affecting physiological condition. The severe population decline that Scyliorhinus canicula has recently undergone should focus our attention on future research supporting robust population modelling to help management of the species.

MORPHOLOGY, DEVELOPMENT, AND BEHAVIOR OF THE IMMATURE STAGES OF THE PARASITE BATHYPLECTES ANURUS (HYMENOPTERA: ICHNEUMONIDAE)

1980 ◽  
Vol 112 (5) ◽  
pp. 481-487 ◽  
Author(s):  
D. P. Bartell ◽  
B. C. Pass
Keyword(s):  
Incubation Period ◽  
Development Time ◽  
Fat Body ◽  
Immature Stages ◽  
Hypera Postica ◽  
Complete Development ◽  
Morphology Development ◽  
And Behavior ◽  
Eggs And Larvae

AbstractObservations, measurements, dissections, and histological preparations were made daily of the eggs and larvae of Bathyplectes anurus (Thomson) while in their host, Hypera postica (Gyllenhal) (Coleoptera: Curculionidae). Observation of development began 24 h after oviposition and ended when parasite larvae emerged from their hosts.Parasite eggs doubled in length and width during their 3- to 4-day incubation period. Parasite larvae fed on hemolymph initially but later instars preferred the fat body and other tissues. B. anurus has five instars. From 18 to 21 days were required for the larvae to complete development and total development time was 21–25 days at 21 ± 1 °C.

Some recent Observations on Busseola fusca (Fuller) (Lep., Noctuidae) in Southern Rhodesia

1960 ◽  
Vol 50 (4) ◽  
pp. 809-819 ◽  
Author(s):  
C. N. Smithers
Keyword(s):  
Feeding Habits ◽  
Light Trap ◽  
Busseola Fusca ◽  
Pupal Stage ◽  
Dry Season ◽  
Egg Laying ◽  
Food Plants ◽  
Larval Feeding ◽  
Appreciable Change ◽  
Southern Rhodesia

The life-history and seasonal cycle of the Lepidopterous borer, Busseola fusca (Fuller), the most serious pest of maize in Southern Rhodesia, have been studied there.There are two generations in the year, the majority of the full-grown larvae of the second entering diapause, in which condition the dry season is passed in the maize stem, but a proportion of the second-generation consists of short-cycle individuals that give rise to moths irregularly during the dry season.In the field, the egg stage lasts about 7–11 days, according to the time of year. In the laboratory, there are six, very occasionally seven, larval instars in the first generation, occupying about 37 days, and the pupal stage lasts about 17 days. In the second (diapausing) generation there may be one or two additional moults without appreciable change in size, and there is considerable variation in the length of instars and in the date of entry into diapause, but by mid-June the bulk of the larvae that will survive are in diapause. The majority of diapause larvae pupate in early November, the pupal stage lasting about 23 days.The feeding habits of the larvae are described and reference is made to other food-plants.The length of life of the adult, in cage conditions, averages 6–7 days, but there is great variation. When provided with diluted honey, adults were not observed to feed, and absence of such food did not appear to impair egg-laying. The sex ratio was 1:1, but in catches at a light-trap the ratio of males to females was 5:1. Copulation takes place shortly after emergence, and oviposition may begin within 24 hours of emergence.The average number of eggs laid per female in cages was 360 over an average of four days, one female laying 1,032. Several batches of eggs may be laid in one night. A single mating appears to be sufficient, but males may copulate with more than one female. Eggs laid by virgin females do not hatch.Diapause is thought to be induced by larval feeding on drying food. Continuous rearing of non-diapause generations can be achieved by feeding the larvae on fresh, green maize. Similarly, in the field, irrigated out-of-season maize will support non-diapause generations and constitute a source of infestation that may render ineffectual the normal routine destruction of all plants of the previous dry-land farming season.The main parasite is the Tachinid, Sturmiopsis parasitica (Curr.), which may destroy more than 33 per cent, of the larvae in either generation.

CYCLE BIOLOGIQUE DE PISSODES NOTATUS (COLEOPTERA, CURCULIONIDAE) DANS LA REGION TOULOUSAINE (FRANCE)

1977 ◽  
Vol 109 (4) ◽  
pp. 597-603 ◽  
Author(s):  
Claude Alauzet
Keyword(s):  
Adult Emergence ◽  
Egg Laying ◽  
Emergence Period ◽  
Cycle Biologique ◽  
Complete Development ◽  
The Third ◽  
Pissodes Notatus ◽  
Field Temperature ◽  
Further Development ◽  
Two Populations

AbstractThe maximal emergence of Pissodes notatus (F.) adults takes place during July and August. It results from the different evolution of two populations:— a first population, whose complete development (from egg to adult) takes 11 or 12 months. This population corresponds to eggs laid after the middle of July (maximum egg laying during September). Most of the larvae having reached the third instar, it shows no more evolution during the winter; the further development takes place during the next spring, and adults emerge from mid-June to mid-July.— a second population resulting from egg laying, between February and July, of hibernated adults (maximum egg laying during April and May). The whole development being very short (2 to 3 months), the adults, corresponding to these eggs, emerge from the middle of July to the end of August.The observed differences between durations of the under-bark development (from 2 to 12 months) appear free of diapause and probably result from rates of development changing with temperature and instar.In our regional field temperature conditions, all the individuals reach finally their under-bark development approximatively at the same time, so that the adult emergence period takes place in July and August.

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