Development of terminal filaments and ovariole envelopes in Thermobia domestica (Insecta, Zygentoma) larvae

• Authors: E. Kisiel , J. Klag
• Languages of publication: EN

Abstracts

EN

The 3rd instar female larvae of Thermobia domestica have five pairs of gonad primordia, each enclosed within a basal lamina (tunica propria). At the end of the 3rd instar some somatic cells scattered on the outer surface of the lamina are seen. During the 4th larval instar the gonad primordia start to form the ovarioles. Each ovariole is elongated and polarized, having anterior and posterior ends. The anterior group of outer somatic cells proliferate to form the terminal filament. At the 6th larval stage the ovarioles are already formed. The terminal filament is separated from the germarium by a thick basal lamina (transverse septum). There are three types of cell building the terminal filament. 1/ Basal cells with numerous finger ? like projections; 2/ Cells with electron lucent cytoplasm and large nuclei, and 3/ Cells with darker cytoplasm containing bundles of fibers and more compact nuclei. The outer surface of the filament is covered by a thick, fibrous basal lamina. The somatic cells that in the previous stages were scattered on the tunica propria as distinct cells, in the 6th larval stage form a cellular envelope (tunica externa). This envelope is formed by a layer of flat cells, and contains numerous tracheae.

Keywords

EN

FILAMENT; OVARIOLE ENVELOPE; THERMOBIA DOMESTICA

Discipline

• ZOOLOGY: ZOOLOGY

• Publisher: Institute of Systematics and Evolution of Animals, Polish Academy of Sciences
• Journal: Folia Biologica
• Year: 2001
• Volume: 49
• Issue: 3-4
• Pages: 199-204

Contributors

author

E. Kisiel

author

J. Klag

• Document Type: ARTICLE
• Publication order reference: J. Klag, Department of Histology and Embryology, Silesian University, Bankowa 9, 40-007 Katowice, Poland