The status of Rhoptrobothrium Shipley et Hornell, 1906 (Cestoda: Tetraphyllidea), with redescription of the type species, R. myliobatidis, and description of three new species from two species of Aetomylaeus (Myliobatiformes: Myliobatidae) from Malaysian Borneo (original) (raw)

Folia Parasitologica 53[3] 189-207 (2006) | DOI: 10.14411/fp.2006.025

1Department of Ecology and Evolutionary Biology and the Natural History Museum and Biodiversity Research Center, University of Kansas, 1200 Sunnyside Ave., Lawrence, Kansas 66045, USA

2Department of Ecology and Evolutionary Biology, University of Connecticut, Unit 3043, 75 N. Eagleville Rd., Storrs, Connecticut 06269-3043, USA

As part of a metazoan parasite survey of elasmobranchs from Malaysian Borneo, specimens of Rhoptrobothrium Shipley et Hornell, 1906 were collected from the eagle rays Aetomylaeus maculatus (Gray) and Aetomylaeus niehofii (Bloch et Schneider). The type species is redescribed from its type host, and a neotype specimen is designated. In addition, three new species of Rhoptrobothrium are described: R. chongi sp. n., R. gambangi sp. n. and R. limae sp. n. Rhoptrobothrium myliobatidis conspicuously differs from the three new species in its lack of a secondary areola; R. limae is distinguished from R. chongi and R. gambangi based on its greater total length; R. chongi possesses conspicuously stalked remi, while R. gambangi possesses short remi, often folded anteriorly. Rhoptrobothrium is somewhat unusual among tetraphyllideans in its possession of a "metascolex," a character it shares with other taxa in the Thysanocephalinae (i.e., Myzocephalus Shipley et Hornell, 1906, Myzophyllobothrium Shipley et Hornell, 1906 and Thysanocephalum Linton, 1889). The morphology of the "metascolex" of Rhoptrobothrium is investigated and new terminology is suggested to standardise the names given to structures constituting a metascolex. As a result, Rhoptrobothrium is considered to possess cephalic peduncle extensions, termed remi. In Rhoptrobothrium, each remus bears, at its distal end, a primary areola, and, in the case of the three new species, also a secondary areola proximal to the primary areola. Myzocephalus and Myzophyllobothrium are tentatively considered to possess remi; the configuration of the "metascolex" of Thysanocephalum, however, is not considered homologous to the condition in the other three genera currently placed in the Thysanocephalinae.

Keywords: Cestoda, Tetraphyllidea, Rhoptrobothrium, Aetomylaeus, Thysanocephalinae, metascolex, Borneo

Received: February 28, 2005; Accepted: May 2, 2006; Published: September 1, 2006 Show citation

ACS AIP APA ASA Harvard Chicago Chicago Notes IEEE ISO690 MLA NLM Turabian Vancouver

Jensen, K., & Caira, J.N. (2006). The status of Rhoptrobothrium Shipley et Hornell, 1906 (Cestoda: Tetraphyllidea), with redescription of the type species, R. myliobatidis, and description of three new species from two species of Aetomylaeus (Myliobatiformes: Myliobatidae) from Malaysian Borneo. Folia Parasitologica,�53(3),�189-207. doi:�10.14411/fp.2006.025

Download citation

References

  1. CAIRA J.N., JENSEN K., HEALY C.J. 1999: On the phylogenetic relationships among tetraphyllidean, lecanicephalidean and diphyllidean tapeworm genera. Syst. Parasitol. 42: 77-151 Go to original source... Go to PubMed...
  2. CAIRA J.N., JENSEN K., HEALY C.J. 2001: Interrelationships among tetraphyllidean and lecanicephalidean cestodes. In: D.T.J. Littlewood and R.A. Bray (Eds.), Interrelationships of the Platyhelminthes. Taylor & Francis, London, pp. 135-158
  3. EUZET L. 1994: Order Tetraphyllidea Carus, 1963. In: L.F. Khalil, A. Jones and R.A. Bray (Eds.), Keys to the Cestode Parasites of Vertebrates. CAB International, Wallingford, England, pp. 149-194
  4. FUHRMANN O. 1931: Dritte Klasse des Cladus Plathelminthes: Cestoidea. In: W. Kuekenthal and T. Krumbach (Eds.), Handbuch der Zoologie (1928-1933). Walter de Gruyter & Co., Berlin, pp. 141-416
  5. OLSON P.D., CAIRA J.N. 1999: Evolution of the major lineages of tapeworms (Platyhelminthes: Cestoidea) inferred from 18S ribosomal DNA and elongation factor-1α. J. Parasitol. 85: 1134-1159 Go to original source... Go to PubMed...
  6. OLSON P.D., LITTLEWOOD D.T.J., BRAY R.A., MARIAUX J. 2001: Interrelationships and evolution of the tapeworms (Platyhelminthes: Cestoda). Mol. Phylog. Evol. 19: 443-467 Go to original source... Go to PubMed...
  7. OLSON P.D., RUHNKE T.R., SANNEY J., HUDSON T. 1999: Evidence for host-specific clades of tetraphyllidean tapeworms (Platyhelminthes: Eucestoda) revealed by analysis of 18S ssrDNA. Int. J. Parasitol. 29: 1465-1476 Go to original source... Go to PubMed...
  8. PINTNER T. 1928: Die sogenannte Gambothriidae, Linton, 1899. Zool. Jahrb., Abt. Anat. Ontog. Tiere 50: 55-116
  9. REGO A.A. 1994: Order Proteocephalidea Mola, 1928. In: L.F. Khalil, A. Jones and R.A. Bray (Eds.), Keys to the Cestode Parasites of Vertebrates. CAB International, Wallingford, England, pp. 257-293.
  10. SCHMIDT G.D. 1986: Handbook of Tapeworms Identification. CRC Press, Boca Raton, Florida, 675 pp
  11. SHINDE G.B., CHINCHOLIKAR L.N. 1980: Mixophyllobothrium okamuri gen. nov. sp. nov. (Cestoda: Tetraphyllida) from Trygon sephen at Ratnagiri, India. Riv. Parassitol. 41: 413-417
  12. SHIPLEY A.E., HORNELL J. 1906: Report on the cestode and nematode parasites from the marine fishes of Ceylon. Report to the Government of Ceylon on the Pearl Oyster Fisheries of the Gulf of Manaar (Herdman), Part 5: 43-96
  13. SOUTHWELL T. 1925: A monograph on the Tetraphyllidea with notes on related cestodes. Mem. Liverpool School Trop. Med. (New Series) 2: 1-368
  14. SOUTHWELL T. 1930: Cestoda. Vol. I. In: J. Stephenson (Ed.), The Fauna of British India, Including Ceylon and Burma. Taylor and Francis, London, 391 pp
  15. WARDLE R.A., McLEOD J.A. 1952: The Zoology of Tapeworms. University of Minnesota Press, Minneapolis, 780 pp
  16. YAMAGUTI S. 1959: Systema Helminthum. Volume II. The Cestodes of Vertebrates. Interscience Publishers, New York, 860 pp