Cestodes of the family Anoplocephalidae Cholodkovsky, 1902, in their adult form, parasitize a variety of hosts, including reptiles, birds and mammals. To complete their life cycle, an intermediate host is required. This study gives a critical review of the life cycles of genera principally important to veterinary medicine (but sporadically infecting man): Anoplocephalinae (Anoplocephala, Anoplocephaloides, Bertiella and Monieziu) and Thysanosomatinae (Avitellina, Stilesia, Thysaniezia and Thysu-nosomu), using data reported by others and our own observations. The accepted paradigm on the biology of the anoplocephalid cestodes is that oribatid mites (Acarina) serve as intermediate hosts. However, as regards the genera Avitellina, Thysaniezia and Thysanosoma, it is still unclear whether oribatid mites are indeed the intermediate hosts, as larval forms (cysticercoids) have also been found in collcmbolans and psocids. Using the controversial biological cycle of Thysanosoma actinioides (Diesing, 1834), a theoretical methodological research proposal for parasitology was constructed which attempts to define a conceptional mark enabling us to predict and explain the parasite-hosts’ related phenomenon. Aspects of this proposal are discussed using the biology of the cestodes of family Anoplocephalidae, as examples.
The taxonomical status of Paranoplocephala bairdi (Schad, 1954)-like cestodes (Anoplocephalidae) in heather voles Phenacomys spp. and tree voles Arborimus spp. (Muridae: Arvicolinae) and their discrimination from five related species of Paranoplocephala is assessed using uni- and multivariate morphometrics. The analyses support the independent status and conspecificity of specimens from Phenacomys spp. and Arborimus spp., and P. bairdi is therefore suggested to be a host-specialist species of heather and tree voles with a wide geographical distribution in North America. A redescription is presented for P. bairdi.
Andrya cuniculi (Blanchard, 1891) (Cestoda: Anoplocephalidae) is redescribed from Oryctolagus cuniculus (L.) from Spain. Large ranges of variability in body length and width, testes number and position of the cirrus sac were observed. An external seminal vesicle covered with small glandular cells is present. The pattern of development of the uterus is similar to that of Andrya rhopalocephala (Riehm, 1881). The only reliable differential characters to distinguish A. cuniculi from A. rhopalocephala are the position of the uterus in gravid segments and the position of the testes in mature segments. The uterus of A. cuniculi occupies the median field and parts of the lateral fields but is restricted to the median field in A. rhopalocephala. Testes are distributed more symmetrically lateral to the female organs in A. cuniculi but are mostly antiporal in A. rhopalocephala.