The caryophyllidean genus Archigetes Leuckart, 1878 is unique among all tapeworms in that its species can mature in invertebrate hosts (Oligochaeta), i.e., have a monoxenic (direct) life cycle. All five species were described as progenetic plerocercoids in oligochaetes and two of them also as adults from cypriniform fishes. Two species, A. sieboldi Leuckart, 1878 and A. iowensis Calentine, 1962, were found in North America in non-native common carp (Cyprinus carpio). A molecular study of caryophyllideans from the southern United States has revealed the occurrence of three new species in native freshwater fishes (Catostomidae, Ictiobinae): Archigetes loculotruncatus n. sp. from Ictiobus bubalus, I. niger and Carpiodes cyprinus is the largest representative of the genus and differs by a loculotruncate scolex. Archigetes megacephalus n. sp. from Ictiobus niger, I. bubalus and I. cyprinellus is characterised by a prominent, bothrioloculodiscate scolex. Archigetes vadosus n. sp. from I. bubalus is typified by a globular scolex with very shallow loculi; it differs from the closely related A. sieboldi in the shape of the body, with a distinct neck region and a scolex wider than the remaining body. Archigetes iowensis Calentine, 1962 becomes a junior synonym of Paraglaridacris limnodrili (Yamaguti, 1934). The generic diagnosis of Archigetes is amended and a key to identification of North American taxa is provided. Species of Archigetes and Paraglaridacris differ from each other most conspicuously in the structure of the ovary, which is follicular in Archigetes versus compact in Paraglaridacris.

TITLE: Archigetes Leuckart, 1878 (Cestoda, Caryophyllidea) : diversité de cestodes de poissons énigmatiques à cycle de vie monoxène. ABSTRACT: Le genre Archigetes Leuckart, 1878 (Caryophyllidea) est unique parmi les cestodes en ce sens que ses espèces peuvent atteindre la maturité chez des hôtes invertébrés (Oligochaeta), c’est-à-dire avoir un cycle de vie monoxénique (direct). Les cinq espèces ont été décrites à partir de plérocercoïdes progénétiques chez des oligochètes et deux d’entre elles aussi à partir d’adultes chez des poissons cypriniformes. Deux espèces, A. sieboldi Leuckart, 1878 et A. iowensis Calentine, 1962, ont été trouvées en Amérique du Nord chez des carpes communes (Cyprinus carpio), non indigènes. Une étude moléculaire des caryophyllidés du sud des États-Unis a révélé la présence de trois nouvelles espèces chez les poissons d’eau douce indigènes (Catostomidae, Ictiobinae). Archigetes loculotruncatus n. sp. d’Ictiobus bubalus, I. niger et Carpiodes cyprinus est le plus grand représentant du genre et est caractérisé par un scolex loculotronqué. Archigetes megacephalus n. sp. d’Ictiobus niger, I. bubalus et I. cyprinellus est caractérisé par un scolex proéminent et bothrioloculodisqué. Archigetes vadosus n. sp. d’I. bubalus est caractérisé par un scolex globulaire avec des loges très peu profondes, et diffère d’A. sieboldi, étroitement apparenté, par la forme du corps, avec une région du cou distincte et un scolex plus large que le reste du corps. Archigetes iowensis Calentine, 1962 devient un synonyme plus récent de Paraglaridacris limnodrili (Yamaguti, 1934). Le diagnostic générique d’Archigetes est modifié et une clé d’identification des taxons nord-américains est fournie. Les espèces d’Archigetes et de Paraglaridacris diffèrent de la manière la plus visible les unes des autres par la structure de l’ovaire, qui est folliculaire chez Archigetes par opposition à compact chez Paraglaridacris.

• Klíčová slova
• Catostomidae, Comparative morphology, Eucestoda, Fish, Histology, Ictiobinae, Molecular prospecting, Nearctic Region, SEM, Species diversity, lsrDNA,
• MeSH
• Cestoda * MeSH
• kapři * MeSH
• máloostní * MeSH
• stadia vývoje MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Severní Amerika MeSH
• Spojené státy americké MeSH

Spermiogenesis in progenetic and adult stages of Archigetes sieboldi Leuckart, 1878, a tapeworm parasitic in oligochaetes and fish respectively, has been examined using transmission electron microscopy and cytochemical staining for glycogen. General pattern of spermiogenesis is essentially like that of other caryophyllideans, i.e., apical dense material in the zone of differentiation in the early stages of spermiogenesis, rotation of free flagellum and a flagellar bud, and proximo-distal fusion. Interestingly, rotation of a free flagellum and flagellar bud to the median cytoplasmic process (MCP) has been observed unconventionally at > 90° only in progenetic stages. Typical striated roots associated with the centrioles occur rarely in A. sieboldi, and only in form of faint structures in advanced stages of spermiogenesis. In contrast to most caryophyllideans studied to date, penetration of the nucleus into the spermatid body has started before the fusion of the free flagellum with the MCP. This feature has been reported rarely but exclusively in the family Caryophyllaeidae. The unipartite mature spermatozoon of A. sieboldi is composed of one axoneme of the 9 + '1' trepaxonematan pattern with its centriole, parallel nucleus, and parallel cortical microtubules which are situated in a moderately electron-dense cytoplasm with glycogen particles. An unusual arrangement of cortical microtubules in the two parallel rows in region I of the spermatozoon is described here for the first time in the Caryophyllidea. Ultrastructural data on spermiogenesis and the spermatozoon in A. sieboldi from tubuficids and carp are compared and discussed with those in other caryophyllideans and/or Neodermata.

• Klíčová slova
• Archigetes sieboldi, Caryophyllidea, Spermatozoon, Spermiogenesis, Ultrastructure,
• MeSH
• axonema ultrastruktura   MeSH
• barvení a značení MeSH
• buněčné jádro fyziologie   MeSH
• Cestoda ultrastruktura   MeSH
• cestodózy veterinární   MeSH
• flagella fyziologie   MeSH
• glykogen analýza   MeSH
• kapři parazitologie   MeSH
• nemoci ryb parazitologie   MeSH
• spermatidy cytologie   ultrastruktura   MeSH
• spermatogeneze fyziologie   MeSH
• transmisní elektronová mikroskopie MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• glykogen MeSH

Vitellogenesis in two spathebothriidean tapeworms, dixenous adult Cyathocephalus truncatus and monoxenous progenetic Diplocotyle olrikii, has been examined using transmission electron microscopy and cytochemical staining with periodic acid-thiosemicarbazide-silver proteinate for glycogen. Each vitelline follicle consists of vitellocytes at various stages of development and one irregularly shaped interstitial cell. Projections of the interstitial cell enclose the vitellocytes and extend as a cytoplasmic sheath on the follicular periphery. An outer thin fibrous layer (= extracellular lamina) covers the cytoplasmic sheath in C. truncatus, but lacks in D. olrikii. Maturing and mature vitellocytes contain vitelline material in the form of single small shell globules that gradually fuse and give rise to the large shell globule clusters. Morphology of shell globule clusters differs slightly in both species. In addition, single "lamellar" granules are present in the cytoplasm of vitellocytes of C. truncatus, but not in D. olrikii. Both electron lucent and electron dense lipid droplets are present in the vitellocytes of C. truncatus, whereas only electron dense lipids occur in D. olrikii. A single lipid droplet turns up occasionally in the nuclei of some of the vitellocytes of C. truncatus. The ultrastructural features of vitellogenesis in spathebothriideans resemble those reported previously in "lower" cestodes, especially in pseudophyllideans.

• MeSH
• Cestoda chemie   fyziologie   ultrastruktura   MeSH
• glykogen analýza   MeSH
• oocyty chemie   fyziologie   ultrastruktura   MeSH
• Schiffova reakce MeSH
• transmisní elektronová mikroskopie metody   MeSH
• vitelogeneze fyziologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• glykogen MeSH