The identification of Anopheles (Nyssorhynchus) rondoni (Diptera: Culicidae) in Mato Grosso, Brazil: an analysis of key character variability

Abstract

A morphological study was made of a population of Anopheles (Nyssorhynchus) rondoni (Neiva and Pinto) from northern Mato Grosso, Brazil. This population usually lacked the primary key character of a dark basal band on hindtarsomere 3, i.e., hindtarsomere 3 was all white as in most other members of the subgenus. It was determined that this species can be recognized instead by the presence of a dark spot on the thorax made up of a large dark prescutellar space that is contiguous with a concolorous central area on the scutellum. A secondary character of a dark area on the costa created by the fusion of the humeral dark, presector dark and sector dark proximal spots is also usually reliable. Regression analyses comparing the lengths and ratios of the dark bands on hindtarsomeres 2 to those on 3 describe a straight line relationship. This suggests that the "atypical" population is at one end of a character gradient. We propose that in the subgenus Nyssorhynchus individuals that have a long basal band on hindtarsomere 2 are more likely to also have a basal band on hindtarsomere 3. The pupal stage of this species has not been previously described. Reared-associated specimens from this study show that the pupa can be easily differentiated from all other Nyssorhynchus by the relatively stout, usually 2 or 3 branched (1-5), setae 1 and 5 on segments IV-VII

Malaria Vectors in Areas of Plasmodium falciparum Epidemic Transmission in the Amazon Region, Brazil

“…Although An. rondoni has previously been identified in other tropical areas, including some areas of Brazil, 23,24 we present here the first report of An. rondoni bearing malaria parasites, although positivity was rather low by ELISA (4 of 110 mosquitoes infected).…”

Description of the Immature Stages of Anopheles (Nyssorhynchus) rondoni (Neiva & Pinto) (Diptera: Culicidae)

“…rondoni was collected as reported earlier (Wilkerson et al 1995b) at Peixoto de Azevedo, State of Mato Grosso, Brazil and by ES Bergo at Bocaina, Rio Jacaré-Pepira, Route 255, Km 125, State of São Paulo, Brazil. Females were blood fed and traumatized by removal of a wing to induce oviposition.…”

“…An. rondoni was studied by Wilkerson et al (1995b). They reported a common variant in the adult which lacked a basal ring on hindtarsomere 3, a character used by Faran (1980).…”

Anopheles (Nyssorhynchus) atacamensis (Diptera: Culicidae), a new species from Northern Chile

“…albitarsis by Lane (1953). Wilkerson et al (1995) proposed that in the subgenus Nyssorhynchus, those individuals with a long dark basal band on hindtarsomere 2 are more likely to have a dark basal band on hindtarsomere 3. This seems to be the case of the melanic form of An.…”