Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Histological analysis of the egg capsule of the ovoviviparous polystomatid monogenean, Pseudodiplorchis americanus

Cable, Joanne, Tocque, K. and Tinsley, R. C. 1997. Histological analysis of the egg capsule of the ovoviviparous polystomatid monogenean, Pseudodiplorchis americanus. International Journal for Parasitology 27 (9) , pp. 1075-1080. 10.1016/S0020-7519(97)00068-4

Full text not available from this repository.


Transmission of Pseudodiplorchis americanus is restricted to the brief period when its host, a desert toad, enters water to spawn. The parasite accumulates its entire annual reproductive output within an elongated uterus during the 10–11-month period of host hibernation. Embryos of P. americanus, at all stages of development, are retained within the uterus which eventually becomes packed with around 150 encapsulated infective larvae. Recently formed eggs, which comprise a fertilized ovum and 2–3 vitelline cells, are closely surrounded by a primary eggshell which stains positively for acidic proteins and keratin. Initially, during passage along the proximal uterus, the egg capsule is only 60 μm in diameter, but as it passes to the distal uterus it expands to 800 μm in diameter to accommodate the growing larva. Due to chemical alterations or complete replacement of the shell, the final (secondary) egg capsule is a large sac-like structure composed of elastin. The flexible nature of this shell maximizes the numbers of infective larvae which can be stored in utero. TEM studies have revealed this capsule to be composed of multi-laminate membranes with a specialized cytoplasmic lining involved in a unique mechanism for embryo nutrition. This is the first report of an elastintype eggshell within the Monogenea

Item Type: Article
Date Type: Publication
Status: Published
Schools: Biosciences
Subjects: Q Science > QL Zoology
Uncontrolled Keywords: Monogenea; Polystomatidae; eggshell; elastin; keratin; histochemistry
Publisher: Elsevier
ISSN: 0020-7519
Last Modified: 04 Jun 2017 06:33

Citation Data

Cited 3 times in Google Scholar. View in Google Scholar

Cited 7 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item Edit Item