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Desarrollo larval de Palaemonetes mexicanus y P. hobbsi (Caridea: Palaemonidae) cultivadas en el laboratorio Larval development of Palaemonetes mexicanus and P. hobbsi (Caridea: Palaemonidae) reared in the laboratory  [cached]
Gabino A. Rodríguez-Almaráz,Rodolfo Mu?iz-Martínez,Alejandro Millán-Cervantes
Revista mexicana de biodiversidad , 2010,
Abstract: Los langostinos del género Palaemonetes ocupan una amplia variedad de hábitats, desde condiciones marinas hasta agua dulce. El desarrollo larval de las especies marinas o salobres es prolongado, mientras que el de las especies de agua dulce es breve. En este estudio se compararon aspectos reproductivos y del desarrollo larval de P. mexicanus y P. hobbsi, especies residentes en cuerpos de agua dulce del noreste de México. Las hembras grávidas de cada especie fueron recolectadas en la localidad tipo y mantenidas en el laboratorio a temperaturas de 22 a 24oC. Las larvas recién eclosionadas obtenidas de estas hembras fueron cultivadas individualmente bajo las mismas condiciones de temperatura y suministrando como alimento larvas de Artemia recién eclosionadas y hojuelas para peces. Tanto P. mexicanus como P. hobbsi, tienen 3 estadios larvales y 2 etapas postlarvales. El tiempo de desarrollo promedio desde zoea I hasta la postlarva II fue de 12 días en P. hobbsi y 16 días en P. mexicanus. La morfología larval de ambas especies es casi idéntica. Sin embargo, existen caracteres morfológicos de cada estadio larval que permiten diferenciar las especies. Se discuten aspectos de fecundidad, biometría de hembras, huevecillos y larvas. The caridean genus Palaemonetes occupies a wide variety of habitats from marine conditions to fresh-water. The marine and brackish species have an extended larval development, while fresh-water species have an abbreviated larval cycle. In this study reproductive aspects and type of larval development were compared between P. mexicanus and P. hobbsi, both fresh-water species from northeast Mexico. Ovigerous females of each species were collected at the type locality and maintained in the laboratory at temperatures between 22 a 24oC. The larvae were reared individually at the same temperature conditions, and newly hatched nauplii of Artemia and fish flakes were provided as food. P. mexicanus and P. hobbsi have an abbreviated development consisting of 3 larval and 2 postlarval stages. The larval cycle including the postlarva had a duration of 12 days for P. hobbsi, while in P. mexicanus lasted 16 days. The larval development of both species is almost identical. However, there are morphological features that can differentiate both species. Aspects of fecundity, biometry of females, eggs and larvae are discussed.
Desarrollo larval de Palaemonetes mexicanus y P. hobbsi (Caridea: Palaemonidae) cultivadas en el laboratorio
Rodríguez-Almaráz, Gabino A.;Mu?iz-Martínez, Rodolfo;Millán-Cervantes, Alejandro;
Revista mexicana de biodiversidad , 2010,
Abstract: the caridean genus palaemonetes occupies a wide variety of habitats from marine conditions to fresh-water. the marine and brackish species have an extended larval development, while fresh-water species have an abbreviated larval cycle. in this study reproductive aspects and type of larval development were compared between p. mexicanus and p. hobbsi, both fresh-water species from northeast mexico. ovigerous females of each species were collected at the type locality and maintained in the laboratory at temperatures between 22 a 24oc. the larvae were reared individually at the same temperature conditions, and newly hatched nauplii of artemia and fish flakes were provided as food. p. mexicanus and p. hobbsi have an abbreviated development consisting of 3 larval and 2 postlarval stages. the larval cycle including the postlarva had a duration of 12 days for p. hobbsi, while in p. mexicanus lasted 16 days. the larval development of both species is almost identical. however, there are morphological features that can differentiate both species. aspects of fecundity, biometry of females, eggs and larvae are discussed.
Descripción del último estadio larval de Neofulla biloba (Plecoptera: Notonemouridae) Description of the last larval instar of Neofulla biloba (Plecoptera: Notonemouridae)  [cached]
Pablo Pessacq
Revista de la Sociedad Entomol?3gica Argentina , 2008,
Abstract: Se describe el último estadio larval de Neofulla biloba (Aubert), desconocido para la ciencia. Se brindan caracteres morfológicos que lo separan de N. areolata (Navás), la única especie del género cuya larva ha sido descripta previamente. The last instar larva of Neofulla biloba (Aubert) is described for the first time. Morphological characters to separate it from that of N. areolata (Navás), the only previously known larva of the genus, are given.
Ultrastructure of the ovary of Dermatobia hominis (Diptera: cuterebridae). I. Development during the 3rd larval instar
Gregorio, E. A.;Secco, V. N. D. P.;Toledo, L. A.;Lello, E.;
Memórias do Instituto Oswaldo Cruz , 1990, DOI: 10.1590/S0074-02761990000300007
Abstract: the ultrastructure and distribution of gonial and somatic cells in the ovary of dermatobia hominis was studied during the 3rd larval instar. in larvae weighing between 400 and 500 mg, the ovary is partially divided into basal and apical regions by oblong somatic cells that penetrate from the periphery; these cells show ovoid nucleus and cytoplasm full of microtubules. in both regions, gonial cells with regular outlines, large nucleus and low electron-density cytoplasm are scattered among the interstitial somatic cells. these later cells have small nucleus and electrodense cytoplasm. clear somatic cells with small nucleus and cytoplasm of very low electron-density are restrict to the apical region of the gonad. degenerating interstitial somatic cells are seen in the basal portion close to the ovary peduncle. during all this larval period the morphological features of the ovary remain almost the same. at the end of the period there is a gradual deposition of glycogen in the cytoplasm of the somatic cells, increase in the number and density of their mitochondria plus nuclear modification as membrane wrinkling and chromatin condensation in masses.
Descripción del último estadio larval de Acanthagrion aepiolum (Odonata: Coenagrionidae) Description of the last instar larva of Acanthagrion aepiolum (Odonata: Coenagrionidae)
Federico Lozano,Analía Garré,Pablo Pessacq
Revista de la Sociedad Entomol?3gica Argentina , 2007,
Abstract: El género neotropical Acanthagrion Selys (Odonata: Coenagrionidae) está integrado por 41 especies. Hasta el momento sólo se ha descripto el último estadio larval de ocho de ellas. En este trabajo, se describe el último estadio larval de Acanthagrion aepiolum Tennessen; sobre la base de cuatro especímenes recolectados en Corrientes (Argentina) y se compara con las demás larvas conocidas para la Argentina. The Neotropical genus Acanthagrion Selys (Odonata: Coenagrionidae) is composed by 41 species, eight of which have the last instar larva described. In this contribution the last instar larva of Acanthagrion aepiolum Tennessen is described based on material collected in Corrientes (Argentina) and it is compared with the larvae known for Argentina.
Description of the last instar larva of Erythrodiplax paraguayensis (Anisoptera: Libellulidae) Descripción del último estadio larval de Erythrodiplax paraguayensis (Anisoptera: Libellulidae)  [cached]
Javier Muzón,Analía Garré
Revista de la Sociedad Entomol?3gica Argentina , 2005,
Abstract: The last instar larva of Erythrodiplax paraguayensis (F rster) is described and illustrated, based on Iberá (Corrientes, Argentina) specimens. A comparative analysis of all hitherto known larvae from Argentina is provided. Se describe e ilustra por primera vez al último estadio larval de Erythrodiplax paraguayensis (F rster) sobre la base de especímenes recolectados en los esteros del Iberá (Corrientes, Argentina). Se brinda además un análisis comparativo de las larvas de especies citadas en la Argentina.
Descripción del último estadio larval de Micrathyria ungulata (Odonata: Libellulidae) Description of the last instar larva of Micrathyria ungulata (Odonata: Libellulidae)
Analía Garré,Federico Lozano
Revista de la Sociedad Entomol?3gica Argentina , 2007,
Abstract: El género Micrathyria Kirby (Odonata: Libellulidae) está integrado por 46 especies, 16 de las cuales se han citado para Argentina. En esta contribución se describe el último estadio larval de Micrathyria ungulata F rster , sobre la base de un espécimen coleccionado en el arroyo Maguire (Buenos Aires, Argentina), y se lo compara con las larvas del género presentes en Argentina. The genus Micrathyria Kirby (Odonata: Libellulidae) is composed by 46 species, 16 of which are known from Argentina. In this contribution we describe the last instar larva of Micrathyria ungulata F rster based on material collected in Maguire stream (Buenos Aires, Argentina) and we compare it with the larvae of the genus recorded in Argentina.
Effects of Quinizarin and Five Synthesized Derivatives on Fifth Larval Instar Midgut Ecdysone 20-Monooxygenase Activity of the Tobacco Hornworm Manduca sexta  [PDF]
Christopher A. Drummond,Maria Teresa Molina,Sandra Taliansky,Carl R. Breidenbach,Carmen F. Fioravanti
International Journal of Zoology , 2014, DOI: 10.1155/2014/261512
Abstract: The plant allelochemical, quinizarin (1,4-dihydroxy-9,10-anthraquinone), and five anthraquinones that were synthesized from quinizarin, namely, 1,4-anthraquinone; 2-hydroxy-1,4-anthraquinone; 2-methoxy-1,4-anthraquinone; 9-hydroxy-1,4-anthraquinone; and 9-methoxy-1,4-anthraquinone, were assessed as to their effects on the essential, P450-dependent ecdysone 20-monooxygenase system of the insect model Manduca sexta (tobacco hornworm). This steroid hydroxylase converts the arthropod molting hormone, ecdysone, to the physiologically required 20-hydroxyecdysone form. M. sexta fifth larval instar midgut homogenates were incubated with increasing concentrations (10?8 to 10?3?M) of each of the six anthraquinones followed by ecdysone 20-monooxygenase assessments using a radioenzymological assay. Four of the five anthraquinones exhibited ’s of about to ?M. The most effective inhibitors were 2-methoxy-1,4-anthraquinone and 1,4-anthraquinone followed by 9-hydroxy-1,4 anthraquinone and 9-methoxy-1,4-anthraquinone. At lower concentrations the latter anthraquinone stimulated E20M activity. Quinizarin was less inhibitory and 2-hydroxy-1,4-anthraquinone was essentially without effect. Significantly, these studies make evident for the first time that anthraquinones can affect insect E20M activity, and thus insect endocrine regulation and development, and that a relationship between anthraquinone structure and effectiveness is apparent. These studies represent the first demonstrations of anthraquinones affecting any steroid hydroxylase system. “This paper is dedicated with admiration to the legacy of Dr. Stan L. Smith, without whom this work and studies like it would not have been initiated.” 1. Introduction Ecdysone 20-monooxygenase (E.C. 1.14.99.22, E20M) is the insect cytochrome P450-dependent steroid hydroxylase responsible for the conversion of the arthropod molting hormone ecdysone (E) to its more active metabolite, namely, 20-hydroxyecdysone (20E) [1, 2]. The nature, regulation, and molecular biology of E20M were elucidated predominantly employing the tobacco hornworm, Manduca sexta, as the model [3–8]. Indeed, the developmental impact of E20M was made evident in midgut tissue of the M. sexta fifth larval instar where E20M activity increases 50-fold between days four and five of the stadium and this increase is inextricably tied to the onset of wandering stage behavior [1, 8, 9]. Moreover, the timing conferred by pulses of 20E was found to be critical to all stages of insect development [1, 10]. The E20M system, therefore, represents a crucial target in terms of
拟黑多刺蚁生活史研究及幼虫龄期划分
Life cycle and larval instar differentiation of Polyrhachis vicina Roger
 [PDF]

王彦男,奚耕思,杨栋梁
- , 2016,
Abstract: 【目的】对拟黑多刺蚁发育生活史及成虫不同品级形态与分工进行详细观察描述,并对幼虫龄期划分进行研究。【方法】在自然光照、温度(26±3) ℃、相对湿度45%~55%的条件下,观察拟黑多刺蚁发育生活史及成虫不同品级形态与分工;根据幼虫体长、头宽、体质量、消化道长,以及幼虫形态特征等数据,并结合戴氏定律,对幼虫龄期进行划分。【结果】在试验条件下,拟黑多刺蚁卵发育期为(24.5±3.5) d、幼虫发育期为(25.0±5.5) d、蛹发育期为(20.5±5.5) d。拟黑多刺蚁幼虫期可分为4个龄期,其中1龄幼虫发育时间为(4.5±1.5) d,2龄幼虫为(5.5±1.5) d,3龄幼虫为(7.0±1.0) d,4龄幼虫为(8.0±1.5) d。【结论】描述了拟黑多刺蚁不同时期的品级分工和形态,明确了拟黑多刺蚁幼虫时期的生物学特性。
【Objective】This paper observed and described life cycle of P.vicina and the shapes and division of labor of adults.The growth and development stages of larva were also differentiated.【Method】Under natural sunlight,temperature of (26±3) ℃,and relative humidity of 45%-55%,life cycle of P.vicina,and shapes and labor division of adults were observed.The morphological characteristics,body length,head width,weight,and digestive tract length of larvae were measured for division of larval development.【Result】In the environment conditions of this study,egg development time was (24.5±3.5) days,larval development period was (25.0±5.5) days,and pupa development period was (20.5±5.5) days.P.vicina larvae stage can be divided into four instars,the first instar was (4.5±1.5) days,the second instar was (5.5±1.5) days,the third instar was (7.0±1.0) days,and the fourth instar was (8.0±1.5) days.【Conclusion】This study described the grade division and morphology of Polyrhachis vicina Roger at different periods
Redescripción de la quetotaxia del cuarto estadio larval de Lutzomyia evansi (Diptera: Psychodidae, Phlebotominae) Redescriptión of the chaetotaxy of the fourth instar larva of Lutzomyia evansi (Diptera: Psychodidae: Phlebotominae)
DALMIRO CAZORLA,MILAGROS OVIEDO,MARíA ALEJANDRA VíVENES
Revista Colombiana de Entomología , 2010,
Abstract: Se redescribe e ilustra la quetotaxia de las larvas del estadio IV de Lutzomyia evansi obtenidas en condiciones de laboratorio. Asimismo, se dan las medidas de las setas. El estudio morfológico comparativo sugiere que las larvas IV de L. evansi, como las demás de la serie verrucarum hasta ahora descritas, pueden colocarse en el Grupo cuatro de las especies flebotominas del Neotrópico que poseen antenas con segmento basal corto y el distal ovoide, lo que pareciera apoyar la correcta agrupación propuesta basada en las características de sus imagos. Se discute la importancia de homogenizar la nomenclatura de la quetotaxia de los flebotominos y el empleo de un solo sistema quetotáxico para su descripción. The chaetotaxy of fourth instar larvae of Lutzomyia evansi, obtained from laboratory conditions, is redescribed and illustrated. Measurements of the setae are also provided. The comparative morphological study suggests that fourth instar larvae of L. evansi, as well as the other species of the verrucarum series, can be placed in Group 4 of the neotropical phlebotomine which posses antennae with a short basal segment and an ovoid distal segment, which seems to support the correct proposed groupings based on characters of the imagos. The significance of the importance to standardize the nomenclature of sand fly chaetotaxy and use of a single chaetotaxy system for their descriptión is discussed.
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