Morphology of the Digestive and Reproductive Systems of Peregrinus maidis (Homoptera: Delphacidae)

Abstract

The corn delphacid, Peregrinus maidis (Ashmead) (Homoptera: Delphacidae) is the only known vector of maize stripe tenuivirus and maize mosaic rhabdovirus in tropical and subtropical areas. The morphology of its digestive and reproductive systems was studied by light microscopy and illustrations were made to aid in dissections and injections of pathogenic innoculum for vector studies. Two salivary glands, located one on each side of the head, extend into the mesothorax. Each gland is divided into two types of lobes which form the principle and accessory glands. The esophagus, a narrow muscular tube, extends from the cibarial diaphragm to the abdomen and empties into the midgut. Parallel to the esophagus, extending from the midgut into the head, is the anterior diverticulum. This closed sac is often filled with air bubbles. The midgut, a tube of uniform diameter, winds in a consistent pattern from the esophagus to the rectum. No filter chamber was observed. The two pairs of Malpighian tubules originate at the posterior end of the midgut with each pair being fused for the proximal two-thirds of their length. The hindgut consists of a rectal sac and rectum. P. maidis females have two large ovaries containing an average of 16 ovarioles. They open successively into the lateral oviduct, the median oviduct, the common oviduct, and the vagina. The spermatheca and the bursa copulatrix open into the common oviduct. A spermathecal gland is also present. The male has two lateral testes with three to four follicles each. A pair of accessory glands fill the abdomen, often extending into the thorax.