Morphological study of the thorax of the five nymphal instars of Triatoma arthurneivai Lent & Martins (Hemiptera, Reduviidae, Triatominae)

Abstract

ABSTRACT. Morphological study of the thorax of the five nymphal instars of Triatoma arthurneivai Lent & Martins (Hemiptera, Reduviidae, Triatominae). Scanning electron microscope (SEM) was done in order to study dorsal, ventral and lateral sides of 1 st , 2 nd , 3 rd , 4 th and 5 th nymphal instars of Triatoma arthurneivai. The five nymphal instar can be recognized based on different pronotum, mesonotum and metanotum shapes and characteristics. In the 1 st instar collar, hairless areas and tubercles are absent. The 2 nd instar presents collar, hairless areas and tubercles. In the 3 rd instar occurs the development of wing pads. In the 4 th instar the four wing pads are expanded, but do not reach the abdomen and in the 5 th instar the anterior wing pads almost overlap the posterior ones. At the ventral side, two metasternal glands openings (1+1) were found in all five nymphal instars. Brindley's gland evaporation areas (1+1) are located at the mesopleuron, as well as an evaporation area is located at the propleuron in all nymphal instars (1+1).KEYWORDS. Distinction; gland; instar; nymph; Triatoma arthurneivai. Lent & Martins (Hemiptera, Reduviidae, Triatominae). Foi feito estudo morfológico da face dorsal, ventral e lateral do tórax de ninfas de 1º, 2º, 3º, 4º e 5º estádios de Triatoma arthurneivai por meio de microscopia eletrônica de varredura. Os cinco estádios ninfais podem ser reconhecidos pelos caracteres morfológicos observados no pronoto, mesonoto e metanoto. No 1º estádio nota-se ausência do colar, áreas glabras e tubérculos, que estão presentes no 2º estádio. No 3º estádio inicia-se a diferenciação das aletas alares. No 4º estádio ocorre expansão das quatro aletas alares, que, no entanto, não alcançam o abdome. No 5º estádio as aletas alares anteriores praticamente recobrem as posteriores. Na face ventral dos cinco estádios ninfais percebe-se duas (1+1) aberturas das glândulas metasternais. As áreas de evaporação das glândulas de Brindley localizam-se na mesopleura. Também foram observadas duas (1+1) áreas de evaporação na propleura dos cinco estádios ninfais. RESUMO. Morfologia do tórax do quinto estádio ninfal de Triatoma arthurneivai

Characterization of the external female genitalia of six species of Triatominae (Hemiptera: Reduviidade) by scanning electron microscopy

“…After euthanasia, the triatomines were transversely cut in the 6th abdominal segment, washed, dehydrated in an alcohol series and oven-dried at 50°C, according to Rosa et al (2005). Subsequently, they were fixed on aluminium stubs by the 6th abdominal segment so that the terminal portion formed an angle of 90° with the support base.…”

Morphological study of the eggs and nymphs of Triatoma dimidiata (Latreille, 1811) observed by light and scanning electron microscopy (Hemiptera: Reduviidae: Triatominae)

“…Schofield and Upton (1978) described these glands in adults of Panstrongylus megistus (Burmeister, 1835), commenting that nymphs are void of them. Millen et al (1979) apud Rosa et al (2005) described the development of the Brindley's glands in 5th instar nymphs of Rhodnius prolixus; Rosa (1995) observed these glands in 1st and 5th instar nymphs of Triatoma circummaculata (Stål, 1859) and Triatoma rubrovaria and Rosa et al (2005) recorded the Brindley's glands in the mesopleura of 5th instar nymphs of Triatoma arthurneivai Martins, 1940. Lent andWygodzinsky (1979) described the urotergites of the 5th instar nymphs of T. dimidiata with a series of five aggregations of granules along the midline and a finely granulose integument.…”

Study on Chagas disease occurrence in the municipality of Monte Negro, State of Rondônia, Brazilian Amazon

“…The insects captured were placed in collecting bottles, labeled, and taken to the laboratory where they were examined and randomly split into two portions -one to be checked for infection by trypanosomatidae specimens and another to be forwarded to the Biologic Sciences Department of the Pharmaceutical Sciences College of Araraquara for morphological identification of the species based on the key elaborated by Lent & Wygodzinsky 13 . The nymph stage was identified based on the works of Correa et al 14 …”