Surface morphology of some Amphistomes (Trematoda) of Amazonian Fishes and the description of a new genus and species

Abstract

-The surface morphology of specimens from ten different genera of amphistomes (Trematoda, Cladorchiidae) from Amazonian fishes is described and illustrated. The importance of body shape as a generic character is considered. Morphological changes as a result of growth are shown and explained in relation to the species Dadaytrema oxycephala. Additionally, Doradamphistoma bacuensis gen. et sp. n. is described from the catfish, Megalodoras irwini Eigenmann, 1925. The new genus and species is elongate and flattened, with external Key-words: fish parasite, trematode, amphistome, Amazonia, Brazil. A Morfologia Superficial de Alguns Anfistomídeos (Trematoda) de Peixes Amazônicos e aRESUMO -A morfologia superficial de espécimens representando dez gêneros diferentes de anfístomos (Trematoda, Cladorchiidae) de peixes amazônicos é descrita e ilustrada. A importância da forma do corpo como caracter genérico é considerada. Modificações morfológicas, como resultado do crescimento, são mostradas e explicadas em relação à espécie Dadaytrema oxycephala. Adicionalmente, Doradamphistoma bacuensis gen. et sp. n. é descrito de um bagre amazônico, Megalodoras irwini. A espécie nova é alongada e achatada, com sacos faringiais externos, um bulbo esofageano, uma bolsa de cirro esférica, um poro genital pós-bifurcal e testículos pré-equatoriais.

First molecular assessment of the interrelationships of cladorchiid digeneans (Digenea: Paramphistomoidea), parasites of Neotropical fishes, including descriptions of three new species and new host and geographical records

“…The only differences between Thatcher's (1999) description of D. bacuense and the present specimens are the presence of an anterior pharyngeal sphincter, which he did not report or illustrate, and the shape of the acetabulum, which has a posteromedial notch ( Figs 1D, 4E) not described by Thatcher but confirmed by a study of the type material (Fig. 1D).…”

“…It closely resembles Anavilhanatrema robustum Thatcher, 1992 (the original spelling "robusta" is emended here because the latin suffix -trema is neuter in gender, not feminine) described from the serrasalmid Pristobrycon striolatus (Steindachner) in Anavilhana Island, Rio Negro, Amazonas, Brazil in the possession of large, tandem testes much wider than long, extramural pharyngeal sacs and intercaecal uterus, but differs by the absence of the anterior collar-like ridge (present in A. robustum), the presence of an oesophageal bulb, postbifurcal genital pore, intestinal caeca ending far from the acetabulum, an entire, not lobed ovary, and intercaecal vitelline follicles (see Jones 2005b). Thatcher, 1999 Figs Remarks. This species was described from M. irwini (= M. uranoscopus) from Manaus in the state of Amazonas in Brazil, and a new genus, Doradamphistoma Thatcher, 1999, was erected to accommodate it by Thatcher (1999).…”

“…Thatcher, 1999 Figs Remarks. This species was described from M. irwini (= M. uranoscopus) from Manaus in the state of Amazonas in Brazil, and a new genus, Doradamphistoma Thatcher, 1999, was erected to accommodate it by Thatcher (1999). He characterised it by well-developed pharynx and extramural pharyngeal sacs, a long oesophagus, sinuous caeca approaching the anterior margin of the acetabulum, testes diagonal, equatorial or pre-equatorial, postbifurcal genital pore, and postequatorial ovary (figured as anterior to the caecal ends).…”

“…Lunaschi (1989) described D. parauchenipteri and compared it only with D. grandistomis, the only option open to her at that time. Ten years later, Thatcher (1999) erected Doradamphistoma, compared it only with Pacudistoma turgida Thatcher, 1992 and was presumably unaware of Lunaschi's (1989) work because he did not, then or in his 2006 book, list the taxon originally erected as Dadaytremoides parauchenipteri as a species of Dadaytremoides or include any references by L.I. Lunaschi.…”

Incidência de enteroparasitos em peixes oriundos de três afluentes do Rio Madeira: Uma questão de Saúde Única em Rondônia, Brasil

“…Esse parasito possui corpo alongado, achatado, lados quase paralelos e extremidades arredondadas. Na literatura, Doradamphistoma bacuensis foi descrito no bagre Megalodoras irwini, em Manaus/ AM, Brasil (Thatcher, 1999).…”