Surface ultrastructure and internal properties of the Erpobdella testacea (Hirudinae, Arynchobdellidae) cocoon membrane.
The Erpobdella testacea cocoon membrane is studied for the first time by transmission and scanning electron microscopy. It has an ovoid form, displays a cambered dorsal side in which various micro-organisms are attached and a flattened ventral side. Symmetrically positioned, 2 opercula occur at the distal ends of the cocoon. The internal ultrastructure reveals fibrils (17.5nm) packed in layers forming C, S, bow shaped, parallel and stippling patterns lines, interrupted by Polygon-shaped cavities (1.8μm). Transverse sections show that each fibril presents an external dark part (6nm) and a central hole approximately 5.06nm in diameter. These features are discussed with bibliographic data signalized for other species. Phylogenetic and functional significations of the cocoon wall structure in leeches are suggested.
Université de Tunis El Manar, Faculté des sciences de Tunis, UR11ES12 Biologie de la reproduction de du développement animal, 2092, Tunis, Tunisia. Electronic address: Romdhaneyasmina@gmail.com.
Yasmina
Y
Romdhane
CNRS - Università di Corsica, Service d'Etudes et de Recherches en Microscopie Electronique, France. Electronic address: quilichini@univ-corse.fr.
Yann
Y
Quilichini
Université de Tunis El Manar, Faculté des sciences de Tunis, UR11ES12 Biologie de la reproduction de du développement animal, 2092, Tunis, Tunisia. Electronic address: saida.tekaya51@gmail.com.
Saida
S
Tekaya
D000818:Animals; D002462:Cell Membrane / Q000648:ultrastructure*; D007865:Leeches / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D011679:Pupa / Q000648:ultrastructure
Cocoon membrane; Erpobdella testecea; Fibrils; Leech; Polygon-shaped cavities; SEM; TEM