Anatomy, Histology, and Ultrastructure of Salivary Glands of the Burrower Bug,Scaptocoris castanea(Hemiptera: Cydnidae)

Abstract

The burrower bug Scaptocoris castanea Perty, 1830 (Hemiptera: Cydnidae) is an agricultural pest feeding on roots of several crops. The histology and ultrastructure of the salivary glands of S. castanea were described. The salivary system has a pair of principal salivary glands and a pair of accessory salivary glands. The principal salivary gland is bilobed with anterior and posterior lobes joined by a hilus where an excretory duct occurs. The accessory salivary gland is tubular with a narrow lumen that opens into the hilus near the excretory duct, suggesting that its secretion is stored in the lumen of the principal gland. The cytoplasm of the secretory cells is rich in the rough endoplasmic reticulum, secretory vesicles with different electron densities and mitochondria. At the base of the accessory gland epithelium, there were scattered cells that do not reach the gland lumen, with the cytoplasm rich in the rough endoplasmic reticulum, indicating a role in protein production. Data show that principal and accessory salivary glands of S. castanea produce proteinaceous saliva. This is the first morphological description of the S. castanea salivary system that is similar to other Hemiptera Pentatomomorpha, but with occurrence of basal cells in the accessory salivary gland.

Ultrastructural Characterization of Salivary Glands, Alimentary Canal and Malpighian Tubules of the Red Shield Bug Carpocoris mediterraneus Tamanini, 1958 (Heteroptera, Pentatomidae)

“…In C. mediterraneus , principal salivary gland has two lobes as anterior and posterior lobes, as in S. pugnax (Pentatomidae; Hamner, 1936), E. heros (Pentatomidae; Castellanos et al, 2017), Scaptocoris castanea Perty, 1830 (Cydnidae; Cossolin et al, 2019) and B. tabidus (Pentatomidae; Carvalho et al, 2021). In Metacanthus elegans L. (Berytidae), Chilacis typhae Perr (Lygaeidae), and Gastrodes ferrugineus L. (Lygaeidae), principal gland is trilobed with anterior, posterior, and lateral lobes (Baptist, 1941).…”

“…In E. heros (Pentatomidae), while the anterior lobe is semi-oval with four irregular projections of different sizes, the posterior lobe is elongated and takes an oval shape with small projections in the proximal lobe (Castellanos et al, 2017). In S. castanea (Cydnidae), the anterior lobe is spherical while the posterior is oval (Cossolin et al, 2019). In P. apterus (Pyrrhocoridae), the posterior lobe is hand-shaped with four distinct finger-like, but other lobes have an oval shape (Özyurt Koçakoğlu, 2021).…”