A revision of Cycloplectanum Oliver, 1968 (Monogenea: Diplectanidae) and descriptions of C. hongkongensis n.sp. and C. lantauensis n.sp. from Epinephelus spp. (Serranidae) in the South China Sea

Abstract

An emended generic diagnosis for Cycloplectanum Oliver, 1968 (Monogenea: Diplectanidae) is provided which emphasizes the importance of the terminal genitalia (penis and vagina) in generic separation. Cycloplectanum americanum (Price, 1937) Oliver, 1968 is recognized as type species of Cycloplectanum. Cycloplectanum epinepheli (Yamaguti, 1938) n.comb., C. serrani (Yamaguti, 1953) n.comb., C. amplidiscatum (Bravo-Hollis, 1955) n.comb., C. latesi (Tripathi, 1955) n.comb., C. melanesiensis (Laird, 1958) n.comb., C. querni (Yamaguti, 1968) n.comb., C. cupatum (Young, 1969) n.comb., C. summanae (Young, 1969) n.comb., C. vagampullum (Young, 1969) n.comb., together with C. hongkongensis n.sp., C. lantauensis n.sp., and C. yamagutii nom.nov., are included in the genus. Cycloplectanum yamagutii nom.nov. is proposed for Pseudorhabdosynochus epinepheli which was named a synonym of C. americanum by G. Oliver in 1968.Based on material from Epinephelus spp. (Serranidae) taken in the South China Sea, redescriptions are presented for C. cupatum and C. vagampullum. In addition, C. hongkongensis n.sp. from E. brunneus and E. awoara and C. lantauensis n.sp. from E. brunneus and E. fario are proposed. The findings of C. cupatum and C. vagampullum on E. fario represent new host and geographic records.

Description of Pseudorhabdosynochus seabassi sp. n. (Monogenea: Diplectanidae) from Lates calcarifer and revision of the phylogenetic position of Diplectanum grouperi (Monogenea: Diplectanidae) based on rDNA sequence data

“…Some parasites were fixed with Bleasure's glue (Acacia gum 17.25%, glycerin 13.79%, chloral hydrate 34.48%, distilled water 34.48%) and their sclerotized parts examined under a dissecting microscope. Parasites were identified to species morphologically according to existing keys and descriptions (Beverley-Burton and Suriano 1981, Liang and Leong 1991, Bu et al 1999, Wu et al 2000, Zhang et al 2001. In total, nine described parasite species were studied in the present study; their codes, numbers, host species, geographical origins and GenBank TM accession numbers of rDNA sequences are listed in Table 1.…”

“…Many species of these monogeneans occur in cultured fish and are of considerable economic importance (e.g., Nash et al 1987, Leong and Wong 1990, Leong 1994. Traditionally, classification of the Diplectanidae Bychowsky, 1957 has been based, to a large extent, on morphology of the sclerotized components of the haptor (Beverley-Burton and Suriano 1981). Two genera of the family are of particular interest because of controversies regarding the taxonomic status and phylogenetic positions of some species within them, and have been the focus of a number of studies (e.g., Oliver 1968, Kritsky andBeverley-Burton 1986).…”

“…The nomenclature and taxonomy of species in Cycloplectanum and Pseudorhabdosynochus has since become controversial and confusing. Beverley- Burton and Suriano (1981) considered that the squamodiscs of Cycloplectanum spp. showed interspecific variation in number and shape of rows, in degree of sclerite fusion and overlap pattern, and these variations should not be considered of prime importance in generic separation.…”

Resolution of the discrepant host-specificity of Pseudorhabdosynochus species (Monogenea, Diplectanidae) from serranid fishes in the tropical Indo-Pacific

“…It was later mentioned by Beverley-Burton and Suriano (1981) from E. merra off Hong Kong. Justine (2005a) redescribed the type-specimens from E. merra and mentioned that the specimens found by Beverley-Burton and Suriano (1981) differed in their dimensions and could well correspond to another species.…”

“…P. vagampullum was not found in any of the numerous diplectanid specimens from E. merra from New Caledonia (Justine 2005a, Hinsinger andJustine 2006b). Zeng and Yang (2007) examined monogeneans from E. quoyanus from the South China Sea and found two species of the cupatus group, which they did not describe, and in addition reported P. vagampullum, P. lantauensis Beverley-Burton et Suriano, 1981 andDiplectanum grouperi Bu, Leong, Wong, Woo et Foo, 1999, and a new species, P. justinei Zeng et Yang, 2007. Pseudorhabdosynochus melanesiensis (Laird, 1958) Kritsky et Beverley-Burton, 1986 was described from E. merra off Vanuatu and Fiji. Justine (2005a) redescribed the species from E. merra off New Caledonia.…”