Morphology of the terminal abdominal segments in females of Triatominae (Insecta: Hemiptera: Reduviidae)

Abstract

Triatominae (Insecta: Hemiptera: Reduviidae) includes 151 extant species that are all potential vectors of Chagas disease. The relationships among these species have been recently studied based on molecular and cytogenetical approaches, and although the morphology of these insects is fairly described, wide comparative studies and cladistics analysis based on this feature are lacking. A comparative study of the terminal abdominal segments in females of 26 species of Triatominae was performed in order to evaluate their importance for the distinction of genera and species, and obtain characters to be used in cladistics analyses. The results showed that the short combined segments IX and X in dorsal view is not diagnostic for Rhodnius, and the elongated trapezoidal dorsal shape of combined segments IX and X is not exclusive of Panstrongylus. There are diagnostic features at the generic level for Rhodnius and Dipetalogaster, but not for the other genera studied. Among the structures examined, tergite IX is the most valuable for distinguishing species of Triatominae. The female terminalia is useful for the specific identification of Triatominae, but cannot be used to diagnose most genera or to directly assess supraspecific relationships. These can only be unveiled by using additional morphological and/or molecular data in broad cladistics analyses.

Rhodnius micki, a new species of Triatominae (Hemiptera, Reduviidae) from Bolivia

“…The resurrection of female genitalia, as an important taxonomic tool, was attributed to Rosa et al (2010) through a detailed study by scanning electron microscopy. Subsequently, several studies corroborate the diagnostic value of female genitalia (Rosa et al 2012(Rosa et al , 2014(Rosa et al , 2017bRodrigues et al 2018). The male external genitalia are usually used for generic and specific differentiation in assassin bugs.…”

Triatoma brasiliensis species complex: characterization of the external female genitalia

“…For taxonomic purposes the tool was also applied to complement the description of Rhodnius montenegrensis (Rosa et al 2012), R. marabaensis (Souza et al 2016), R. taquarussuensis (Rosa et al 2017) and Nesotriatoma confusa (Oliveira et al 2018) and in the characterization of 35 species distributed in seven genera (Rosa et al 2012, 2017, De Oliveira et al 2015, Dos Santos Souza et al 2016, Mendonça et al 2016, Rivas et al 2017, Souza et al 2017, Rodrigues et al 2018). Here, the morphological study of the female external structures of the species of the T. brasiliensis complex was analyzed for the first time and provided a relevant contribution for the group.…”

“…Here, for the first time, the morphology of the external genitalia of the females have been analyzed by scanning electron microscopy (SEM) in the T. brasiliensis complex. This technique has been applied in several other studies in order to broaden the specific concepts and relationships within triatomine groups (Rosa et al 2010, 2014, De Oliveira et al 2015, Rivas et al 2017, Rodrigues et al 2018).…”

Redescripción de las especies del género Eratyrus Stål (Hemiptera: Reduviidae: Triatominae): nueva propuesta para la distinción interespecífica y una breve nota biogeográfica

“…En trabajos posteriores se ha señalado que, pese a que ambas especies son muy similares y difíciles de distinguir morfológicamente, un carácter diferencial importante es la porción libre de la vesica del genital externo del macho (Lent y Wygodzinsky 1979). Recientemente se describió la morfología de los segmentos abdominales de la hembra de E. mucronatus (dos Santos et al 2018), lo cual coincide con nuestros resultados. Sin embargo, en los anteriores trabajos además de no fundamentarse suficientemente los caracteres distintivos entre E. mucronatus y E. cuspidatus, no se incluyen otros de especial interés taxonómico.…”