Abstract
Three species of Temnocephala have been reported on Aegla from Uruguay: Temnocephala axenos, Temnocephala mertoni and Temnocephala talicei. As part of a systematic review of the Uruguayan species of Temnocephala, a fourth species was found on Aegla platensis and Aegla uruguayana. This species, new for the genus, has the following diagnostic characters: Large temnocephalan; slightly curved penial stylet (225 µm in length) with a symmetrical introvert (27 long by 18 µm in diameter) that has at least 44 spine-like projections, each bearing 7 rows of internal spines; a seminal vesicle that opens sub-polarly into the contractile vesicle; a muscular vagina with a strong asymmetrical sphincter; preequatorial nephridiopores close to the internal borders of the elongate-oval excretory syncytia; a large pharynx with anterior and posterior sphincters of about the same diameter and a narrow pharyngeal lumen with nearly uniform width. To contemplate the characters of the pharynx, an amendment of the genus Temnocephala is given. The new species resembles Temnocephala cyanoglandula, which also has a very long, slightly curved penial stylet, but differs from it by having a shorter penial stylet, a lower number of rows of spines in the introvert, a larger, different type of pharynx, a smaller contractile vesicle and a larger sucker. The new species is carnivorous and feeds on whole preys, which are mainly annelids (Stratiodrilus) and other species of Temnocephala. The new species was found to be hyperparasitised by plerocercoid and nematode larvae, but hyperparasites were not found in the other sympatric species of Temnocephala. Based on the findings presented here, it is clear that detailed histological descriptions of the pharynx should be contemplated as part of the normal work in taxonomy of temnocephalans.
References
Amato, J.F.R., Amato, S.B. & Daudt, L.C.C. (2003) New species of Temnocephala Blanchard (Platyhelminthes, Temnocephalida) ectosymbiont on Aegla serrana Buckup & Rossi (Crustacea, Anomura) from southern Brazil. Revista Brasileira de Zoologia, 20, 493–500.
https://doi.org/10.1590/S0101-81752003000300021Amato, J.F.R., Amato, S.B., Seixas, S.A., Vidigal, T.H.D.A. & Andrade, C.D.P. (2011) Trichoptera — the newest insect order host of temnocephalans (Platyhelminthes, Temnocephalida) and the description of a new species of Temnocephala from Brazil. Zootaxa, 2975, 47–58.
Baer, J.G. (1929) Contribution à l'étude des Temnocéphales, Dactylocephala madagascariensis (Vayssière, 1892). Bulletin Biologique de la France et de la Belgique, 63, 540–561, pls. 11–12.
Bond-Buckup, G. & Buckup, L. (1994) A familía Aeglidae (Crustacea, Decapoda, Anomura). Arquivos de Zoologia, 32, 159–346.
https://doi.org/10.11606/issn.2176-7793.v32i4p159-346Cannon, L.R G. (1993) New temnocephalans (Platyhelminthes): ectosymbionts of freshwater crabs and shrimps. Memoirs of the Queensland Museum, 33, 17–40.
Cannon, L.R.G. & Jennings, J.B. (1987) Occurrence and nutritional relationship of four ectosymbiotes of the freshwater crayfishes Cherax dispar Riek and Cherax punctatus Clark (Crustacea: Decapoda) in Queensland. Australian Journal of Marine and Freshwater Research, 38, 419–427.
https://doi.org/10.1071/MF9870419Collins, P.A., Giri, F. & Williner, V. (2011) Biogeography of the freshwater decapods in the La Plata Basin, South America. Journal of Crustacean Biology, 31, 179–191.
https://doi.org/10.1651/10-3306.1Cordero, E.H. (1946) Ophiotaenia cohospes n. sp., de la tortuga fluvial Hydromedusa tectifera Cope, una larva plerocercoide en el parénquima de Temnocephala brevicornis Mont., y su probable metamorfosis. Comunicaciones Zoologicas del Museo de Historia Natural de Montevideo, 2 (34), 1–15.
Damborenea, M. C. 1991. Temnocephala (Platyhelminthes, Temnocephalidae) de la Argentina: revisión de caracteres específicos. Iheringia, Série Zoologia, 71, 111–120.
Damborenea, M.C. (1992) Especies de Temnocephala (Platyhelminthes, Temnocephalidea) de crustáceos y moluscos de la Argentina. Iheringia, Série Zoologia, 72, 3–21.
Damborenea, M.C. & Cannon, L.R.G. (2001) On Neotropical Temnocephala (Platyhelminthes). Journal of Natural History, 35, 1103–1118.
https://doi.org/10.1080/00222930152434454Dioni, W. (1967a) Temnocephalas uruguayas II. Descripción de Temnocephala talicei n. sp. y notas sobre T. axenos Monticelli (Platyhelmintha). Physis, 26, 477–484.
Dioni, W. (1967b) Temnocephalas argentinas. II. Las Temnocephalas de Aegla del Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” (Platyhelmintha). Physis, 26, 509–514.
Dioni, W. (1967c) Vehiculismo sobre Aegla (Decapoda, Anomura). Los seres epizoicos y sus relaciones interespecíficas. Physis, 27, 41–52.
Fitzpatrick, B.M., Fordyce, J.A. & Gavrilets, S. (2008) What, if anything, is sympatric speciation? Journal of Evolutionary Biology, 21, 1452–1459.
https://doi.org/10.1111/j.1420-9101.2008.01611.x
Hickman, V.V. (1967) Tasmanian Temnocephalidea. Papers and Proceedings of the Royal Society of Tasmania, 101, 227–251.
Jennings, J.B. (1968) A new temnocephalid flatworm from Costa Rica. Journal of Natural History, 2, 117–120.
https://doi.org/10.1080/00222936800770671Jennings, J.B. (1971) Parasitism and commensalism in the Turbellaria. Advances in Parasitology, 9, 1–32.
https://doi.org/10.1016/S0065-308X(08)60158-XJoffe, B.I., Solovei, I.V. & Cannon, L.R.G. (1995) The structure of the epidermis in Didymorchis (Temnocephalida: Platyhelminthes). Australian Journal of Zoology, 43, 631–641.
https://doi.org/10.1071/ZO9950631Joffe, B.I., Solovei, I.V., Watson, N.A. & Cannon, L.R.G. (1997) Structure and evolution of the pharynx in the Temnocephalida (Platyhelminthes). Canadian Journal of Zoology, 75, 205–226.
https://doi.org/10.1139/z97-028Lamothe-Argumedo, R. (1981) Un caso raro de parasitismo. Anales del Instituto de Biología, Universidad Nacional Autónoma de México, Serie Zoología, 51, 675–682.
Langeron, M. (1949) Précis de Microscopie. Technique-Expérimentation-Diagnostic. Masson et Cie., Libraires de L’académie de Médecine, Paris, 1430 pp.
Merton, H. (1914) Beiträge zur Anatomie und Histologie von Temnocephala. Abhandlungen der Senckenbergischen Naturforschenden Gesellschaft, 35, 1–58.
Ortmann, A.E. (1902) The geographical distribution of freshwater decapods and its bearing upon ancient geography. Proceedings of the American Philosophical Society, 1, 267–400, figs. 1–8.
https://doi.org/10.5962/bhl.title.16020Oyanedel, A., Valdovinos, C., Sandoval, N., Moya, C., Kiessling, G., Salvo, J. & Olmos, V. (2011) The southernmost freshwater anomurans of the World: Geographic distribution and new records of Patagonian aeglids (Decapoda: Aeglidae). Journal of Crustacean Biology, 31, 396–400.
https://doi.org/10.1651/10-3427.1Pereira, C. & Cuocolo, R. (1940) Contribuição para o conhecimento da morfologia, bionomia e ecologia de “Temnocephala brevicornis” Monticelli, 1889. Arquivos do Instituto Biologico de Saõ Paulo, 11, 365–397.
Pereira, C. & Cuocolo, R. (1941) Estudos sobre “Temnocephalidae Monticelli, 1899”, com estabelecimento de dois novos gêneros australianos e descrição de duas novas espécies neotrópicas. Arquivos do Instituto Biologico de Saõ Paulo, 12, 101–127.
Pérez-González, M.D. (1949) Sobre a digestão e a respiração das Temnocephalas (Temnocephala bresslaui, spec. nov.). Boletins da Faculdade de Filosofia, Ciências e Letras da Universidade de São Paulo, Zoologia, 14, 277–324.
https://doi.org/10.11606/issn.2526-4877.bsffclzoologia.1949.129116Pérez-Losada, M., Bond-Buckup, G., Jara, C.G. & Crandall, K.A. (2004) Molecular systematics and biogeography of the southern South American fresh-water “crabs” Aegla (Decapoda: Anomura: Aeglidae) using multiple heuristic tree search approaches. Systematic Biology, 53, 767–780.
https://doi.org/10.1080/10635150490522331
Ponce de León, R. (1980) Especies americanas de Temnocephalidea Benham (Platyhelmintha). I. Descripción de Temnocephala rochensis n. sp. de la cámara paleal de Pomacea canaliculata (Lamarck). Revista de Biología del Uruguay, 7, 39–48.
Ponce de León, R. (1989) Description of Temnocephala haswelli sp. n. (Platyhelminthes) from the mantle cavity of Pomacea canaliculata (Lamarck). Journal of Parasitology, 74, 524–526.
https://doi.org/10.2307/3282900Ponce de León, R., Berón Vera, B. & Volonterio, O. (2015) Description of a new Temnocephala species (Platyhelminthes) from the southern Neotropical Region. Journal of Parasitology, 101, 424–428.
Potter, P.E. (1997) The Mesozoic and Cenozoic paleodrainage of South America: a natural history. Journal of South American Earth Sciences, 10, 331–344.
https://doi.org/10.1016/S0895-9811(97)00031-XPoulin, R. (1999) Body size vs abundance among parasite species: positive relationships? Ecography, 22, 246–250.
https://doi.org/10.1111/j.1600-0587.1999.tb00499.x
Rivas, L.R. (1964) A reinterpretation of the concepts "Sympatric" and "Allopatric" with proposal of the additional terms "Syntopic" and Allotopic". Systematic Zoology, 13, 42–43.
https://doi.org/10.2307/2411436Santos, S., Bond-Buckup, G., Buckup, L., Pérez-Losada, M., Finley, M. & Crandall, K.A. (2012) Three new species of Aegla (Anomura) freshwater crabs from the upper Uruguay River hydrographic basin in Brazil". Journal of Crustacean Biology, 32, 529–540.
https://doi.org/10.1163/193724012X635935Schmitt, W. (1942) The species of Aegla, endemic South American freshwater crustaceans. Proceedings of the United States National Museum, 91, 431–520, pls. 25–28.
Sébillot, P. (1883) Gargantua dans les traditions populaires. Maisonneuve et Cie., Paris. 390 pp.
Seixas, S.A., Amato, J.F.R. & Amato, S.B. (2011) A new species of Temnocephala Blanchard (Platyhelminthes, Temnocephalida) ectosymbiont on Dilocarcinus septemdentatus (Decapoda, Trichodactylidae) from the Brazilian Amazonia. Neotropical Helminthology, 5, 201–212.
Sewell, K.B., Cannon, L.R.G. & Blair, D. (2006) A review of Temnohaswellia and Temnosewellia (Platyhelminthes: Temnocephalida: Temnocephalidae) ectosymbionts from Australian crayfish Euastacus (Parastacidae). Memoirs of the Queensland Museum, 52, 199–280.
Toon, A, Perez-Losada, M., Schweitzer, C.E., Feldmann, R.M., Carlson, M., Crandall, K.A. (2010) Gondwanan radiation of the Southern Hemisphere crayfishes (Decapoda: Parastacidae): evidence from fossils and molecules. Journal of Biogeography, 37, 2275–2290.
https://doi.org/10.1111/j.1365-2699.2010.02374.xVolonterio, O. (2007a) Análisis filogenético de las especies de Temnocephala Blanchard, 1849 (Platyhelminthes, Temnocephalida) del Uruguay, con énfasis en la evaluación de la monofilia de las especies epizoicas de Ampullariidae (Mollusca, Gastropoda). M.S. Thesis. Facultad de Ciencias, Universidad de la República (PEDECIBA), Montevideo, 279 pp.
Volonterio, O. (2007b) A new species of Temnocephalidae (Platyhelminthes, Temnocephalida) from Uruguay, with a detailed description of Uruguayan material of Temnocephala axenos. Journal of Natural History, 41, 1245–1257.
tps://doi.org/10.1080/00222930701360208
Volonterio, O. (2009a) First report of the introduction of an Australian Temnocephalidan into the New World. Journal of Parasitology, 95, 120–123.
https://doi.org/10.1645/GE-1726.1
Volonterio, O. (2009b) Redescription and designation of Neotypes of Temnocephala talicei Dioni, 1967 (Platyhelminthes, Temnocephalida). Journal of Parasitology, 95, 345–348.
https://doi.org/10.1645/GE-1733.1
Volonterio, O. (2010) Two new species of Temnocephala (Platyhelminthes, Temnocephalida) from the South American snake-necked turtle Hydromedusa tectifera (Testudines, Chelidae). Zoological Science, 27, 965–970.
https://doi.org/10.2108/zsj.27.965Weber, M. (1889) Über Temnocephala Blanchard. Zoologische Ergebnisse einer Reise in Niederländisch Ost-Indien, 1, 1–29.
Williams, J.B. (1980) Morphology of a species of Temnocephala (Platyhelminthes) ectocommensal on the isopod Phreatoicopsis terricola. Journal of Natural History, 14, 183–199.
https://doi.org/10.1080/00222938000770181Xu, Y.Q., Rao, X.Z. & Chen, Y.S. (2006) New distribution location of Temnocephala semperi in Fujian Province, China. Chinese Journal of Zoology, 41, 82–87.