Feinstruktur der Tarsal-Drüse von Siro duricovius (Joseph) (Opiliones, Sironidae)

Abstract

All species of Sironidae possess as a secondary male sex character an epidermal gland organ in the last tarsal joint of the fourth leg. The glandular secretion emanates from a conical apophysis, the adenostyl, which is located dorsally on the joint. In Siro duricorius (Joseph, 1868) the complex organ consists of numerous functional units, the secretion of which flows into the common channel opening on the adenostyl. Every gland unit contains 5 cells: 3 gland cells (DZ), 1 enveloping cell (HZ), 1 duct cell (KZ). The enveloping cell connects the gland cells with the duct cell like a sleeve. A marginal fold of the gland cell apex provides tight connection of gland cells and enveloping cell. Gland cells and enveloping cell are equipped with microvilli, and both cell types secrete in a common reservoir. The duct of the duct cell is divided into two parts: 1) a distal fibrillaceous-spongy one and 2) a proximal massive one. Both are accompanied only by a single duct cell. Besides this complex gland organ a similar one is located in the ventral part of the tarsus. Its collecting channel opens into the channel of the main gland. Isolated functional gland units are scattered over the epidermis of the tarsus; their secretion flows immediately on the tarsal surface. The gland cells proper produce a protein, the fact is indicated by the electronmicrographs. The secretion of the enveloping cell is a different one, but at this time cannot be attached to a chemical group. © 1979 Springer-Verlag.