Triatoma melanocephala, Neiva & Pinto, 1923, Neiva & Pinto, 1923

de Oliveira, Jader, Chaboli Alevi, Kaio Cesar, Nascimento, Juliana Damieli, Mendonça, Vagner José, Freitas de Araújo, Renato & da Rosa, João Aristeu, 2023, Description of the spermathecae and testicles of Triatoma melanocephala Neiva & Pinto, 1923 (Hemiptera: Reduviidae: Triatominae), Revista Chilena de Entomología (Rev. Chil. Entomol.) 49 (2), pp. 271-278 : 273-274

Results

Optical microscopy

The complete female reproductive system of T. melanocephala has: two ovaries, two lateral oviducts, a common oviduct, two spermathecae, an accessory gland, and a genital chamber. The study of ovaries of adult females of T. melanocephala showed that they are double and consist of several ovarioles, as it can be seen in Fig. 1A . The ovaries are divided into three parts: terminal filament, ovarian or ovary tubes, and peduncle or chalice. The terminal filament ends on the thoracic adipose body, promoting the positioning of the ovary. The ovary is covered by a tunic of its own, which is lined externally by the peritoneal membrane that goes from the lateral oviduct to the terminal filament, having little contact with the ovaries.

The spermathecae of T. melanocephala presented a variation in the positioning ( Fig. 1 ) and differences in size and shape depending on whether they are full or empty of sperm ( Figs. 1B, C ). Slim insertions were found in the common oviduct, and there were large and medium bodies with rounded terminal portions ( Figs. 1B, C ).

The complete male reproductive system has: two testicles, two vas deferens, seminiferous vesicle, two accessory glands and ejaculatory duct. The testicles of T. melanocephala have seven testicular follicles that are encased by a peritoneal sheath ( Figs. 2A, B, C ). They presented an irregular contour, approximately ellipsoid shaped, and a transparent coloration with slight vitreous luster ( Fig. 2A ).

Scanning Electron Microscopy

The spermathecae of T. melanocephala showed a rounded shape with variations when they are full of sperm. When empty, they presented the same format in all samples analyzed ( Fig. 3 ).

The testicles of T. melanocephala presented a rounded shape, having a differentiation in the regions of connection with anterior vas deferens and terminal filament ( Fig. 4 ).

Figures

Figure 1. Female reproductive system of adult T. melanocephala by optical microscopy. A. Overview of the (ov) ovarioles magnification 10X. B. Full spermathecae. C. Nearly empty spermathecae. (sp) spermathecae Magnification 40x./Sistema reproductivo femenino del adulto de T.melanocephala visto por microscopia óptica. A. Visión general de los (ov) ovariolos con aumento de 10X. B. Espermatecas llenas. C. Espermatecas casi vacÍas. (sp) espermatecas. Aumento de 40x.

Figure 2. Male reproductive system of adult maleT. melanocephala by optical microscopy.A. Overview of the (Te) testicles; magnification 20X. B. Overview of the (Ft) follicles testicular; magnification 20x. C. Overview of the (du) ductus deferens 20x; (ag) accessory glands 20x and (sv) seminiferous vesicle; magnification 20x. /Sistema reproductivo masculino del adulto de T. melanocephala visto por microscopÍa óptica. A. Visión general de los (Te) testÍculos; aumento de 20x. B. Visión general de los (Ft) folÍculos testiculares; aumento de 20x. C. Visión general del (du) conducto deferente; 20x; (ag) glándulas accesorias 20x y (sv) vesÍcula seminal; aumento de 20x.

Figure 3. Female reproductive system by scanning electron microscopy (SEM). A. Spermathecae adult female T. melanocephala: (sp) spermathecae; (R¹ and R²) region where the cuts for assembling the parts were made where two oviducts side and genital second camera (RamÍrez Pérez 1969). B. Detail of spermathecae. / Sistema reproductivo femenino observado por microscopÍa electrónica de barrido (MEB). A. Espermatecas de la hembra adulta de T. melanocephala: (sp) espermatecas; (R¹ y R²) región donde se realizaron los cortes para el ensamblaje de las partes donde se encuentran los dos oviductos laterales y la segunda cámara genital (RamÍrez Pérez 1969).B. Detalle de las espermatecas.

Figure 4. Testicles of adult male T. melanocephala by (A) Testicle dorsal view (B) Testicle ventral view by scanning electron microscopy. / TestÍculos del adulto de T. melanocephala observados por (A) vista dorsal del testÍculo (B) vista ventral del testÍculo mediante microscopÍa electrónica de barrido.