Observações sôbre o Triatoma rubrofasciata (De Gerr, 1773) no Estado da Guanabara

Os autores realizando capturas de Triatomíneos na favela do Morro do Telégrafo (São Cristóvão - GB), onde as construções, na sua maioria são de barro ou estuque puderam, constatar: 1) - Todos os exemplares capturados eram da espécie Triatoma rubrofasciata (De Geer, 1.773). 2) - De 170 domicílios examinados, foram encontrados triatomíneos em 23, sendo que o mínimo de triatomíneos por casa foi de 1 exemplar e o máximo de 56 exemplares. Esta última cifra foi obtida em duas capturas consecutivas no mesmo local. 3 - Entre 115 exemplares capturados, 8 eram ninfas do 1º estágio, 15 de 2º, 10 de 3º, 5 de 5º, 11 de 6º, 42 eram adultos machos e 24 fêmeas 4) - Nenhum dos hemipteros examinados mostrou-se infectado por qualquer flagelado. 5) - A reação de precüpitina feita em 17 exemplares revelou resultado positivo para sangue humano em 15, para rato em 1 e para porco e galinha em 1.

Aspectos da Biologia e Etologia de Paulinia acuminata (De Geer), 1773 (Orthoptera: Pauliniidae), um gafanhoto semi-aquático, na Amazônia Central

Paulinia acuminata (Orthoptera: Pauliniidac) desenvolve todo seu ciclo vital em macrófitas aquáticas. Entre 17 macrófitas e 5 hortaliças testadas, a oviposição foi constatada somente em Salvinaceae (Salvinia auriculata, S. minima, S. sprucei, Azolla cf. microphylla e Araceae (Pistia stratiotes). O período médio de incubação, em laboratório, foi de 18,7 (+/- 1,8) dias, com uma média de 7,3 (+/- 2,8) ovos por postura. O desenvolvimento dos seis estádios ninfais durou 47,12 (+/-1,2) dias. O ciclo de vida completo, ovo-adulto, foi de 93,2 dias sob uma temperatura do ar em torno dc 29 °C. Observações etológicas de laboratório e de campo são apresentadas.

Aceitabilidade alimentar de Paulinia acuminata (De Geer, 1773) (Orthoptera: Pauliniidae) na Várzea da Amazônia Central

Ninfas e adultos do gafanhoto Paulinia acuminata aceitaram como alimento cinco (5) espécies de macrófitas aquáticas entre as 20 testadas, durante 12 dias: Pistia stratiotes, Salvinia auriculata, S. minima, Azolla sp. e Ludwigia natans. As baixas taxas de sobrevivência de adultos (26%) alimentados com Azolla sp. e de ninfas (40%) e adultos (30%) em L. natans indicam que estas plantas podem representar recursos alimentares alternativos. Experimentos com P. stratiotes e S. auriculata dentro de gaiolas flutuantes, no campo, sem P. acuminata, resultaram num aumento do peso fresco das plantas (51-64%). Com 20 gafanhotos (ninfas e adultos) houve decréscimo de peso (40-45%). Estes dados reforçam o potencial dc P. acuminata como agente de controle biológico de macrófitas aquáticas específicas.

Life Cycle and Reproductive Patterns of Triatoma rubrofasciata (De Geer, 1773) (Hemiptera: Reduviidae), under Laboratory Conditions

The life cycle and reproductive patterns of Triatoma rubrofasciata were studied along with laboratory conditions for the establishment of a prolific colony. The insects were divided into four groups: two of them were maintained at room temperature (20.5°C to 33°C and 85% ± 5% of relative humidity), the other two in a climatic chamber (CC) (temperature: 29°C, humidity: 80% ± 5%). The groups were fed weekly or fortnightly on Swiss mice. The females from the group kept in the CC and fed weekly had longer life span, as well as a higher number of eggs, fertile eggs and hatchings; the group kept in the CC and fed fortnightly had a shorter life span for the 1st, 2nd and 3rd instars and a lower mortality rate for all instars. It was concluded that a constant high temperature (CC at 29°C) is the most suitable condition for the maintenance of a colony of T. rubrofasciata regardless of the interval between repasts.

Resistance to Starvation of Triatoma rubrofasciata (De Geer, 1773) under Laboratory Conditions (Hemiptera: Reduviidae: Triatominae)

The present work aims at learning the period of resistance to starvation (molting/death) of Triatoma rubrofasciata in different stages of development and the respective loss of weight until death. Eggs of specimens from the greater area of the city of São Luis in the State of Maranhão, Brazil, yielded approximately 300 nymphs. These nymphs were placed in labelled Borrel glasses, in which they were weekly fed on rats (Rattus norvegicus), until reaching the stage to be observed. The experiments were conducted in a climatic chamber regulated at 29 ± 1° C, 70% relative humidity and 12 hr photoperiod. The resistance to starvation increased according to the stage of development, except for adult bugs, whose results were similar to the 3rd stage nymphs. In all these development stages there was an abrupt loss of weight in the first week, followed by a gradual loss until death. Comparing this work with those of other authors, it was observed that T. rubrofasciata is among the less resistant triatomine species.

Tabela de vida de fertilidade de Lysiphlebus testaceipes (Cresson, 1880) (Hymenoptera, Aphidiidae) em Schizaphis graminum (Rondani, 1852) (Hemipera, Aphididae)

Life table analyses have been developed to understanding the impact of various sources of intrinsic and extrinsic mortalities on the rate of population growth. The understanding of the population increase of the parasitoids related to their hosts is important in biological control programs. This work had as objective to evaluate the survival and fertility of the parasitoid Lysiphlebus testaceipes (Cresson, 1880) on Schizaphis graminum (Rondani, 1852) as a host under fertility life table. The experiment were carried out in a climatic chamber at 25 ± 1ºC, RH 60 ± 10% and 10h photophase. To determine the immature mortality, the development time and the sex ratio of the parasitoid, 12 females of the parasitoid (less than one day old) and 240 nymphs of S. graminum (3 days old) were used. To evaluate the longevity and fertility of L. testaceipes, 15 females (less than one day old) were used. Nymphs of S. graminum (3 days old) were offered for each parasitoid female daily, until the female died, being in the 1st day - 300 nymphs; 2nd day - 250 nymphs; 3rd day - 200 nymphs; 4th day - 150 and in the other days a number of 50 nymphs. L. testaceipes had an immature mortality of 22,2%, and a development time of males and females of 9.0 and 9.1 days, respectively. The females of L. testaceipes laid, in it first life day, 257.8 eggs, and they survived up until seven days. The net reproduction rate (Ro) and the intrinsic rate of increase (r m) were respectively, 301.9 and 0.513. The finite rate of increase (l) was 1.67 females per day, the mean length of a generation (T) was 11.13 days and the time to duplicate the population (TD) was 1.35 weeks. The parasitoid L. testaceipes have a high potential of population growth on S. graminum as a host under the analyzed conditions.

Nova espécie e sinonímia em Braderochus Buquet, 1852 (Coleoptera, Cerambycidae, Prioninae)

Braderochus hovorei sp. nov. proveniente da Colômbia (Boyacá) é descrita e figurada. Nova sinonímia: B. shuteae Bleuzen, 1994 = B. dentipes (Chemsak, 1979) comb. nov.