Epinepheli Yamaguti Research Articles

Monogeneans from Epinephelus chlorostigma (Val.) (Perciformes: Serranidae) off New Caledonia, with the description of three new species of diplectanids

Gill monogeneans from the brownspotted grouper Epinephelus chlorostigma (Val.) collected in deep water off the coral barrier reef of New Caledonia, South Pacific, comprise seven species. These include the ancyrocephalid Haliotrema sp., the capsalid Allobenedenia cf. epinepheli Yamaguti, 1968, and five diplectanids, namely Pseudorhabdosynochus epinepheli (Yamaguti, 1938), reported in a previous paper, P. cyanopodus Sigura & Justine, 2008 and P. podocyanus Sigura & Justine, 2008, two species originally described from E. cyanopodus Richardson, P. stigmosus n. sp., P. exoticoides n. sp. and Diplectanum femineum n. sp. P. stigmosus is characterised by a sclerotised vagina with a straight primary canal, large ovoid primary chamber and spherical secondary chamber. P. exoticoides is a highly aberrant species, with a thick-walled male quadriloculate organ and a discoid sclerotised vagina with an exceptional structure. Interestingly, P. exoticoides resembles P. exoticus Sigura & Justine, 2008, a species from E. cyanopodus, and P. stigmosus resembles P. cyanopodus and P. podocyanus, also both from E. cyanopodus, suggesting close relationships between the diplectanid faunae of these two fish species. D. femineum belongs to a group of diplectanids, provisionally classified as 'Diplectanum' Diesing, 1858, which all share a small funnel-shaped male copulatory organ. In contrast to other members of this group which have no sclerotised vagina, D. femineum has a sclerotised vagina with the same organisation as those of species of Pseudorhabdosynochus Yamaguti, 1958. This suggests that the species of 'Diplectanum' from groupers are closer to Pseudorhabdosynochus than suggested by the structure of the male organs.

A redescription of Pseudorhabdosynochus epinepheli (Yamaguti, 1938), the type-species of Pseudorhabdosynochus Yamaguti, 1958 (Monogenea: Diplectanidae), and the description of P. satyui n. sp. from Epinephelus akaara off Japan.

Pseudorhabdosynochus epinepheli (Yamaguti, 1938) has been recorded from a variety of hosts, mainly groupers. All type-specimens of Diplectanum epinepheli Yamaguti, 1938, Pseudorhabdosynochus epinepheli Yamaguti, 1958 and Cycloplectanum hongkongensis Beverley-Burton & Suriano, 1981 are figured: it is concluded, as did Kritsky & Beverley-Burton (1986), that the three species are synonymous. In addition, numerous monogenean specimens from a deep-sea grouper, Epinephelus chlorostigma, collected off New Caledonia, South Pacific, were prepared using various methods and described. These specimens are also conspecific with P. epinepheli (Yamaguti, 1938) and represent a new geographical record. This species has a sclerotised vagina with a very characteristic primary chamber. The simultaneous presence of P. lantauensis (Beverley-Burton & Suriano, 1981) and P. epinepheli was noted in both type-slides of D. epinepheli from Japan (host: E. akaara) and C. hongkongensis from Hong Kong (host: E. bruneus). Several causes are suspected for the alleged 'generalist' character of P. epinepheli, including the misidentification of either fish or monogeneans and the accidental exchanges of monogeneans between fishes of different species kept alive in the same tank. Finally, the confirmed list of hosts of P. epinepheli includes E. akaara, E. awoara and E. chlorostigma; it is suggested that the latter, a widespread deep-sea fish, serves as a reservoir for the infection of the other species, which are associated with shallow waters. P. satyui n. sp. is described from two specimens found on slides from E. akaara (from the Inland Sea of Japan) deposited by Yamaguti; the new species has a sclerotised vagina with characteristic spherical chambers.

Pseudopycnadena tendu sp. nov. (Digenea, Opecoelidae) in the yellow-spotted triggerfish Pseudobalistes fuscus (Perciformes, Balistidae) and additional opecoelids parasitizing fishes from the waters off New Caledonia

AbstractPseudopycnadena tendu sp. nov. is described from the balistid Pseudobalistes fuscus from the waters off New Caledonia. It differs from the only other member of the genus P. fischthali Saad-Fares et Maillard, 1986, in its broad cirrus-sac, with the wide field of large gland-cells, its less nearly circular body shape, its dorsal excretory pore, its shorter post-testicular region, its relatively larger ventral sucker and its smaller eggs. The genus is re-defined to take these distinctions into account. Other opecoelid species reported from New Caledonia are Allopodocotyle epinepheli (Yamaguti, 1942) from Epinephelus cyanopodus, E. fasciatus and E. merra, Cainocreadium epinepheli (Yamaguti, 1934) from E. coeruleopunctatus, E. fasciatus and Variola louti, Hamacreadium mutabile (Linton, 1910) from Lutjanus fulviflamma and L. kasmira, Helicometra epinepheli Yamaguti, 1934 from E. fasciatus and E. merra, Orthodena tropica Durio et Manter, 1968 from Lethrinus lentjan, Pacificreadium serrani (Nagaty et Abdel-Aal, 1962) from Plectropomus leopardus and Pseudoplagioporus interruptus Durio et Manter, 1968 from Lethrinus rubrioperculatus.

Species of Caligus Müller, 1785 (Copepoda: Caligidae) parasitic on marine fishes of Taiwan.

Six species of copepods of the genus Caligus (Caligidae, Siphonostomatoida) parasitic on marine fishes of Taiwan are reported. They are: C. absens n. sp. from Priacanthus blochii and P. macracanthus; C. epinepheli Yamaguti, 1936 from Scolopsis vosmeri; C. kanagurta Pillai, 1961 from Decrapterts kurroides; C. laticaudus Shiino, 1960 from Lutjanus vitta and Parapristiopoma trilineatum; C. nengai Rangnekar, Rangnekar & Murti, 1953 from Triacanthus biaculeatus; and C. rotundigenitalis Yü, 1933 from Drepane punctata, Liza macrolepis and Terapon jarbua. C. distortus Pillai & Natarajan, 1977 is relegated to a synonym of C. nengai and C. multispinosus Shen, 1957 reported by Lin et al. (1994) from the cultured sea bream Acanthopagrus schlegeli is a misidentification for C. rotundigenitalis Yü, 1933.

The status of the genera Hysterolecithoides Yamaguti, 1934, Neotheletrum Gibson & Bray, 1979 and Machidatrema León-Règagnon, 1998 (Digenea: Hemiuroidea), including a description of M. leonae n. sp. from Australian waters.

A diagnosis is given for the lecithasterid genus Hysterolecithoides Yamaguti, 1934, which is now found to have two to six (possibly seven) vitelline masses. The species H. frontilatus (Manter, 1969) is returned to the genus, having been considered a member of the bunocotylid genus Neotheletrum by recent authors. It is redescribed from Siganus nebulosus, Moreton Bay, and S. doliatus, Lizard Island, Great Barrier Reef and New Caledonia, with emphasis on the presence of Juel's organ, a uterine seminal receptacle and the blind sac associated with the genital atrium. It differs from its congeners in the trajectory of the pars prostatica which recurves dorsally to the sinus-sac. Oligolecithoides Shen, 1982 is synonymised with Hysterolecithoides and O. trilobatus Shen, 1982 is synomised with H. epinepheli Yamaguti, 1934. Machidatrema León-Règagnon, 1998 is diagnosed, and found to be close to Hysterolecithoides, but differs in the lack of a blind-sac projecting from the dorsal genital atrium, by its tandem testes, the coiling of the uterus between the testes and the ovary, and the ventral excretory pore. M. leonae n. sp. is described from Siganus fuscescens, S. lineatus, S. doliatus, S. corallinus, S. vulpinus and Scarus globiceps at Heron Island, Queensland. It differs from its closest congener, M. akeh, in the muscular and tegumental flap over the genital pore and details of the terminal genitalia. M. chilostoma (Machida, 1980) and M. kyphosi (Yamaguti, 1970) are redescribed from Kyphosus vaigiensis from Heron Island. Neotheletrum Gibson & Bray, 1979 is diagnosed: it differs from Hysterolecithoides in its confluent excretory arms, blind seminal receptacle (no Juel's organ) and uniformly tripartite vitellarium. A cladistic analysis suggests that M. chilostoma and M. kyphosi are not best accommodated in Machidatrema, that Machidatrema (sensu stricto) is monophyletic and that Hysterolecithoides is paraphyletic. Hysterolecithoides and Machidatrema are considered hysterolecithine lecithasterids, whilst Neotheletrum is retained as an opisthadenine bunocotylid.

Three diplectanid monogeneans from marine finfish (Epinephelus spp.) in the Far East

Two new species of diplectanid monogeneans, Diplectanum grouperi and Pseudorhabdosynochus coioidesis from the marine finfish Epinephelus coioides and E. aerolatus(Serranidae), cultured in floating cages in Malaysia, Indonesia and Hong Kong, were described and compared with P. lantauensis Beverley-Burton and Suriano, 1981 from the same hosts. There is no other close species sharing the features of Diplectanum grouperi. The possession of a copulatory organ with an open cup-like proximal part and a narrow tubular distal part is a main distinguished feature of D. grouperi. Pseudorhabdosynochus coioides is most closely related to P. epinepheli Yamaguti, 1938, but can be distinguished from it by the shape and the size of the haptor, hamuli, copulatory organ, the lack of a muscular bulbus ejaculatorius, a greater number of rows in the squamodiscs and the location of the testis. Pseudorhabdosynochus lantauensis from the present hosts differs from that described from the original hosts, Epinephelus brunneus and E. fario in the shape of the dorsal bar and vagina.

Three diplectanid monogeneans from marine finfish (Epinephelus spp.) in the Far East

Two new species of diplectanid monogeneans, Diplectanum grouperi and Pseudorhabdosynochus coioidesis from the marine finfish Epinephelus coioides and E. aerolatus(Serranidae), cultured in floating cages in Malaysia, Indonesia and Hong Kong, were described and compared with P. lantauensis Beverley-Burton and Suriano, 1981 from the same hosts. There is no other close species sharing the features of Diplectanum grouperi. The possession of a copulatory organ with an open cup-like proximal part and a narrow tubular distal part is a main distinguished feature of D. grouperi. Pseudorhabdosynochus coioides is most closely related to P. epinepheli Yamaguti, 1938, but can be distinguished from it by the shape and the size of the haptor, hamuli, copulatory organ, the lack of a muscular bulbus ejaculatorius, a greater number of rows in the squamodiscs and the location of the testis. Pseudorhabdosynochus lantauensis from the present hosts differs from that described from the original hosts, Epinephelus brunneus and E. fario in the shape of the dorsal bar and vagina.

Branchial parasites of Epinephelus guaza (L.) in the Canary archipelago.

Groupers (Epinephelus malabaricus Bloch et Schneider) obtained from a fish market (i.e., wild population) and those cultured in floating cages were examined for parasites. Sixteen and 11 species of parasites were recovered from cultured and wild groupers, respectively. All fish examined were infested with one or more species of parasite. The overall mean intensity of infestation was about three times higher in cultured (449) than in wild (197) groupers. The diplectanid monogenean, Pseudorhabdosynochus epinepheli Yamaguti 1938, was the most abundant parasite recovered, with a high mean intensity of 335 in the cultured and 127 in the wild fish; 97.2% and 77.1% of the cultured and wild groupers, respectively, were infested by the trematode Prosorhynchus pacificus Manter 1940, with a mean intensity of 81 (cultured) and 72 (wild). Ergasilus borneoensis Yamaguti 1954 was found only in 19% of the cultured groupers, with a mean intensity of 177.Cultured groupers have a greater variety of parasites and higher intensities of infestation than wild groupers. The high numbers of parasites in cultured groupers may be an important factor leading to the frequently observed outbreaks of disease in floating cages.

A comparative study of the parasite fauna of wild and cultured grouper ( Epinephelus malabaricus Bloch et Schneider) in Malaysia

Groupers ( Epinephelus malabaricus Bloch et Schneider) obtained from a fish market (i.e., wild population) and those cultured in floating cages were examined for parasites. Sixteen and 11 species of parasites were recovered from cultured and wild groupers, respectively. All fish examined were infested with one or more species of parasite. The overall mean intensity of infestation was about three times higher in cultured (449) than in wild (197) groupers. The diplectanid monogenean, Pseudorhabdosynochus epinepheli Yamaguti 1938, was the most abundant parasite recovered, with a high mean intensity of 335 in the cultured and 127 in the wild fish; 97.2% and 77.1% of the cultured and wild groupers, respectively, were infested by the trematode Prosorhynchus pacificus Manter 1940, with a mean intensity of 81 (cultured) and 72 (wild). Ergasilus borneoensis Yamaguti 1954 was found only in 19% of the cultured groupers, with a mean intensity of 177. Cultured groupers have a greater variety of parasites and higher intensities of infestation than wild groupers. The high numbers of parasites in cultured groupers may be an important factor leading to the frequently observed outbreaks of disease in floating cages.

Some Digenetic Trematodes of Marine Fishes of New Caledonia. Part II. Opecoelidae and Lepocreadiidae

Nine species of Opecoelidae and four species of Lepocreadiidae are reported. Opecoelidae: new genera are Orthodena and Pacificreadium; new species are Choanostoma secundum, Orthodena tropica, and Pseudoplagioporus interruptus. Other opecoelid species are Helicometra fasciata (H. epinepheli Yamaguti, 1934, new synonymy), Allopodocotyle serrani, Hamacreadium mutabile, H. diacopae, Pseudoplagioporus lethrini, and Pacificreadium serrani. Five species of Hamacreadium are transferred to Cainocreadium, resulting in the following new combinations: C. pteroisi, formerly H. pteroisi Nagaty and Abdel Aal, 1962; C. epinepheli, formerly H. epinepheli Yamaguti, 1934; C. gulella, formerly H. gulella Linton, 1910; C. longisaccum, formerly H. longisaccum Siddiqi and Cable, 1960; and C. lintoni, formerly H. lintoni Siddiqi and Cable, 1960. Pacificreadium serrani was formerly H. serrani Nagaty and Abdel Aal, 1962. Cainocreadoides Nagaty, 1956, is considered a synonym of Cainocreadium. Lepocreadiidae: new genus is Intusatrium; new species are I. robustum, I. secundum, IIolorchis plectorhynchi, and Neolepidapedon dollfusi. The following trematodes are part of a collection made in New Caledonia by H. W. Manter in June and July 1963. A total of 46 species of Digenea were obtained from about 40 species of fishes. Descriptions and records of 12 species of these Digenea have been published (Durio and Manter, 1968). We are indebted to Mrs. Rene Catala, Acting Director (1963) of the Noumea Aquarium, for use of the Aquarium in examination of the fishes. No trematodes had previously been collected from fishes in New Caledonia, which is a place of interest because of its geographical location midway between Fiji and Australia. Species also recorded in this paper as from Australia are based on collections made there by H. W. Manter in 1963. All measurements are in microns except as otherwise noted. OPECOELIDAE OZAKI, 1925 Choanostoma secundum sp. n. (Fig. 1) Hosts: Plectorhynchus sp.; Lutjanidae; type host Lutjanus vitta (Quoy and Gaimard); Lutjanidae. Location: Intestine. Number: 7 from Plectorhynchus sp.; 1 from Lutjanus vitta. Holotype: USNM Helm. Coll. No. 63309. Received for publication 22 April 1968. * Studies from the Department of Zoology, University of Nebraska, No. 387. Supported by NSF Grant No. GB 468. t University of Southwestern Louisiana, Lafayette. $ University of Nebraska, Lincoln. Description: Body unspined, anterior end truncate; posterior end tapered but rounded; length 1.288 to 1.792 mm; width near acetabular level, 365 to 470. Oral sucker large, inverted bellshaped, 308 to 381 long by 221 to 308 wide at anterior end. Acetabulum immediately pre-equatorial, 193 to 233 wide. Sucker ratio 1:0.73 to 0.87. Forebody contractile. Prepharynx absent; pharynx 143 to 172 long by 66 to 98 wide; esophagus about twice length of pharynx, bifurcating a little anterior to acetabulum; ceca narrow, not reaching posterior end of body by short distance. Genital pore near left anterior edge of acetabulum. Testes two, subspherical, diagonal to almost tandem, in posterior fourth of body, close together or separated by short space. Cirrus sac very long and rather slender, extending from genital pore along left side of acetabulum, then obliquely, ending to right of midline at level of anterior testis or even to posterior testis. Total length of cirrus sac often 1/ body length or more. Cirrus sac containing bipartite seminal vesicle connected with long, unarmed cirrus by short duct with circular muscles; prostatic cells not abundant but stretched along most of cirrus sac. Ovary subspherical, immediately anterior to anterior testis; seminal receptacle anterior to ovary; Mehlis' gland at right posterior edge of ovary. Uterus extending posteriorly in single loop, usually passing between testes (rarely to one side) to near posterior end of body, or, in young specimens, not posterior to testes; metraterm with circular muscles, about 1/3 length of cirrus sac. Vitellaria extending from midesophageal level to near posterior end of body, confluent anterior to acetabulum, elsewhere lateral. Eggs yellow, 53 to 58 by 33 to 37. Excretory pore terminal; excretory vesicle wide, extending to posterior edge of acetabulum. The name secundum refers to the fact it is the second species to be named in the genus.