Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: V. Five new species of Thaparocleidus Jain, 1952 (Ancylodiscoididae) from Pangasius Nasutus

The examination of gill parasites from Pangasius nasutus (Bleeker, 1862) (Siluriformes, Pangasiidae) revealed the presence of five new species of Monogenea, all belonging to Thaparocleidus Jain, 1952 (Monogenea, Ancylodiscoididae) as defined by Lim (1996) and Lim et al. (2001): T. serpens n. sp. T. ocrea n. sp., T. megagripus n. sp., T. citreum n. sp. and T. alatus n. sp.     

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: VI. Pangasitrema camillae n. g., n. sp. (Monogenea, Ancylodiscoididae), from Pangasius polyuranodon

The examination of gill parasites from Pangasius polyuranodon Bleeker, 1852 (Siluriformes, Pangasiidae) in Indonesia revealed the presence of a new species of Manogenea, belonging to a new genus: Pangasitrema camillae n. g., n. sp. (Ancylodiscoididae). Among Ancylodiscoididae, the genus has several distinguishing features: the reduced size of the haptor, the morphology and size of gripi, the absence of a ventral transversal bar and of a cuneus associated with dorsal gripi.     

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: VII. Six new host-specific species of Thaparocleidus Jain, 1952 (Ancylodiscoididae) from Pangasius polyuranodon

The examination of gill parasites from Pangasius polyuranodon Bleeker, 1852 (Siluriformes, Pangasiidae) revealed the presence of six new host-specific species of Monogenea, all belonging to Thaparocleidus Jain, 1952 (Monogenea, Ancylodiscoididae) as defined by Lim (1996) and Lim et al. (2001): T. caestus n. sp., T. crassipenis n. sp., T. legendrei n. sp., T. levangi n. sp., T. slembroucki n. sp. and T. virgula n. sp.     

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: IX. Two new species of Thaparocleidus Jain, 1952 (Ancylodiscoididae) from Pangasius mahakamensis

The examination of gill parasites from P. mahakamensis Pouyaud, Gustiano & Teugels, 2002 (Siluriformes, Pangasiidae) in Southeast Asia revealed the presence of three species of Monogenea. One (Thaparocleidus caecus (Mizelle & Kritsky, 1969)) had been previously described. The other two, belonging to Thaparocleidus Jain, 1952 (Monogenea, Ancylodiscoididae) as defined by Lim (1996) and Lim et al. (2001), are considered new species: T. pouyaudi n. sp. and T. teugelsi n. sp.     

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: VIII. Four new species of Thaparocleidus Jain, 1952 (Ancylodiscoididae) from Pangasius polyuranodon and P. elongatus

The examination of gill parasites from Pangasius polyuranodon Bleeker, 1852 and P. elongatus Pouyaud, Gustiano & Teugels, 2002 (Siluriformes, Pangasiidae) in Southeast Asia revealed the presence of four new species of Monogenea all belonging to Thaparocleidus Jain, 1952 (Monogenea, Ancylodiscoididae) as defined by Lim (1996) and Lim et al. (2001): T. furcus n. sp., T. infundibulus n. sp., T. sudartoi n. sp. and T. turbinatio n. sp.     

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: II. Four new species of Thaparocleidus Jain, 1952 (Ancylodiscoidinae) from Pangasius humeralis.

The examination of gills from two rare endemic species of Pangasius Valenciennes, 1840 (Siluriformes, Pangasiidae): P. humeralis Roberts, 1989 (five specimens) and P. lithostoma Roberts, 1989 (six specimens) from the Kapuas River (West Kalimantan province, Bomeo Island, Indonesia) revealed the presence of four new species of Monogenea belonging to the genus Thaparocleidus Jain, 1952 (Monogenea, Ancylodiscoidinae) on P. humeralis: T. sinespinae n. sp., T. brevicochleus n. sp., T. kapuasensis n. sp. and T. gustianoi n. sp., and not any on P. lithostoma.     

Ergasilus thatcheri n. sp. (Copepoda, Poecilostomatoida, Ergasilidae) from the gills of Rhamdia quelen (Teleostei, Siluriformes, Pimelodidae) from southern Brazil

The female of Ergasilus thatcheri n. sp. (Copepoda, Poecilostomatoida, Ergasilidae) is described from the gills of the "jundiá," Rhamdia quelen (Teleostei, Siluriformes, Pimelodidae), from fish ponds in the State of Rio Grande do Sul, Brazil. The new species has a falciform semipinnate terminal seta on the first exopod, which suggests phylogenetic affinity to 10 other congeners, all from fishes of the Amazon Basin. Based on general morphology, the new species shows great similarity to E. callophysus Thatcher and Boeger, 1984, a parasite of another pimelodid fish Callophysus macropterus. Ergasilus thatcheri n. sp., however, can be easily differentiated from E. callophysus in its possession of a more distal sensillum not located on a cuticular elevation, and a row of spinules on the inner margin of the second antennal segment (first endopodal segment).     

Complete mitochondrial genome of Liobagrus obesus (Siluriformes, Amblycipitidae)

Liobagrus obesus (Siluriformes, Amblycipitidae) is an endemic, endangered species in South Korea. Throughout this study, complete mitochondrial genome of L. obesus was sequenced, which is 16,506 bp in length. Its detail characteristics were described in this study.     

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: I. Five new species of Thaparocleidus Jain, 1952 (Ancylodiscoidinae) from Pangasius pangasius, P. kinabatanganensis, P. rheophilus and P. nieuwenhuisii

The examination of gill parasites from Pangasius pangasius (Hamilton, 1822); P. kinabatanganensis Roberts & Vidthayanon, 1991; P. rheophilus Pouyaud & Teugels, 2000 and P. nieuwenhuisii (Popta, 1904) (Siluriformes, Pangasiidae) in Southeast Asia revealed the presence of six species of Thaparocleidus Jain, 1952 (Monogenea, Ancylodiscoidinae). One has been previously described from P. pangasius: T. pangasi (Tripathi, 1957). The other five are new species: T. chandpuri n. sp. from P. pangasius; T. bahari n. sp. and T. sabanensis n. sp. from P. kinabatanganensis; T. redebensis n. sp. from P. rheophilus and T. mahakamensis n. sp. from P. nieuwenhuisii.     

A review of the Arhythmacanthidae (Acanthocephala) with a description of Heterosentis hirsutus n. sp. from Cnidoglanis macrocephala (Plotosidae) in Australia

Heterosentis hirsutus n. sp. is described from Cnidoglanis macrocephala (Siluriformes: Plotosidae) from the Swan Estuary, Western Australia. It is distinguished by having 14 longitudinal rows of 6-7 hooks per row on the proboscis, a trunk armed anteriorly and posteriorly (= genital spines) with minute spines and lemnisci that may extend to the posterior margin of the proboscis receptacle. The new species also has prominent fragmented nuclei in its trunk wall. New information is given for Heterosentis plotosi Yamaguti, 1935 from Plotosus lineatus (Siluriformes: Plotosidae) and H. paraplagusiarum (Nickol, 1972) Amin, 1985 from Paraplagusia guttata (Pleuronectiformes: Cynoglossidae), both from Queensland. A key to the species of Heterosentis Van Cleave, 1931 is provided. The Arhythmacanthidae subfamilies are reviewed: there is little utility in the recognition of these taxa because of the small number of genera involved and the validity of the characters on which they are based is in doubt, particularly whether trunk spines are present or absent. Only Acanthocephaloides Meyer, 1932, Breizacanthus Golvan, 1969, Euzetacanthus Golvan & Houin, 1964, Heterosentis, Hypoechinorhynchus Yamaguti, 1939 and Paracanthocephaloides Golvan, 1969 of the Arhythmacanthidae are considered valid. A key to these genera is provided. The monotypic genus Neoacanthocephaloides Cable & Quick, 1954 is considered a new synonym of Acanthocephaloides thus creating Acanthocephaloides spinicaudatus (Cable & Quick, 1954) n. comb. Arhythmacanthus Yamaguti, 1935 is maintained as a synonym of Heterosentis because the distinction between two and three hook types is made equivocal when the transition between the apical and subapical hooks is gradual.     

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: X. six new species of Thaparocleidus Jain, 1952 (Ancylodiscoididae) from Pangasius micronema

The examination of gill parasites from Pangasius micronemao Bleeker, 1847 (Siluriformes, Pangasiidae) in Southeast Asia revealed the presence of nine species of Monogenea. Two (Thoparocleidus brevicochleus Pariselle, Lim & Lambert, 2001 and T. sinespinoe Pariselle, Lim & Lambert, 2001) have been previously described. Among the others, six species, belonging to Thaporocleidus Jain, 1952 (Monogenea, Ancylodiscoididae) as defined by Lim (1996) and Lim et al. (2001), are considered new species: T. tacitus n. sp., T. summagracilis n. sp., T. portentosus n. sp., T rukyonii n. sp., T. durandi n. sp., and T. lebrunce n. sp. The remaining species is represented by too few individuals to be conclusively described.     

Seven new species of Quadriacanthus Paperna, 1961 (Monogenea) from the gills of Heterobranchus longifilis and H. isopterus from the Ivory Coast,West Africa

The gills of two species of Siluriformes, Heterobranchus longifilis and H. isopterus collected from the Rivers Agnéby and Bia in the Ivory Coast (West Africa) revealed the presence of seven new species of Quadriacanthus Paperna, 1961 (Monogenea: Ancyrocephalidae). The following parasites are described: Quadriacanthus longifilisi n. sp., Q. thysi n. sp., Q. ayameensis n. sp., Q. agnebiensis n. sp., Q. simplex n. sp., Q. gourenei n. sp. and Q. macrocirrus n. sp.     

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: III. Five new species of Thaparocleidus Jain, 1952 (Ancylodiscoididae) from Pangasius bocourti,P. djambal and P. hypophthalmus

The examination of gill parasites from Pangasius bocourti Sauvage, 1880; P. djambal Bleeker, 1846; P. hypophthalmus (Sauvage, 1878) and P. gigas Chevey, 1930 (Siluriformes, Pangasiidae) revealed the presence of seven species of Monogenea among which five are considered new species. They all belong to Thaparocleidus Jain, 1952 (Ancylodiscoididae) as defined by Lim (1996) and Lim et al. (2001). P. bocourti: T. combesi n. sp., T. komarudini n. sp. and T. vietnamensis n. sp. P. djambal: T. caecus (Mizelle & Kritsky, 1969), T. combesi n. sp., T. euzeti n. sp., T. komarudini n. sp. and T. sadilii n. sp. P. hypophthalmus: T. caecus, T. siamensis (Lim, 1990) and T. vietnamensis n. sp. P. gigas: no Monogenea were found on this host species.     

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: IV. Five new species of Thaparocleidus Jain, 1952 (Ancylodiscoididae) from Pangasius krempfi,P. kunyit,P. mekongensis and P. sabahensis

The examination of gill parasites from Pangasius krempfi Roberts & Vidthayanon, 1991; P. kunyit Pouyaud et al., 1999; P. mekongensis Gustiano et al., in press and P. sabahensis Gustiano et al., in press (Siluriformes, Pangasiidae) in Southeast Asia revealed the presence of six species of Monogenea, all belonging to the genus Thaparocleidus Jain, 1952 (Monogenea, Ancylodiscoididae) as defined by Lim (1996) and Lim et al. (2001). One has been previously described (T. vietnamensis Pariselle et al., 2002), five are considered as new species: T. humerus n. sp. and T. culter n. sp. on P. kunyit; T. mehurus n. sp. and T. culteroides n. sp. on P. sabahensis; and T. phuongi n. sp. on the four studied host species. The latter one, due to slight morphometric differences linked to geographical origin of hosts, is described as made up of three sub-species: T. phuongi phuongi n. sub-sp., T. phuongi malaysiensis n. sub-sp. and T. phuongi indonesiensis n. sub-sp.     

Length–weight relationship of seven marine catfishes (Siluriformes: Ariidae) in the Amazon Coastal Zone (Brazil)

Length–weight relationships (LWR) were determined for seven commercially important species of catfishes (Siluriformes, Ariidae) from the Amazon Coastal Zone (ACZ), Brazil. The analyses included 3628 specimens sampled in three trawling expeditions: dry season of 1996 (111 hauls), rainy season of 1997 (120 hauls), and dry season of 1997 (120 hauls). Bottom‐trawl nets were utilized for sampling. Length‐weight estimates for Amphiarius phrygiatus, Amphiarius rugispinis, Aspistor quadriscutis, Notarius grandicassis, Sciades couma, Sciades parkeri and Sciades proops.     

Sex,reproductive cycle and variations in the fecundity of the family schilbeidae (Osteichthyes : Siluriformes) in Lake Kainji,Nigeria.

The sex, reproductive cycle and variations in the fecundity of the family Schilbeidae (Osteichthyes : Siluriformes) in Lake Kainji, were investigated. Sexual differences in size and morphology were found to exist in all species. Sex ratio varied with species and season. There were more females than males in the population. Size at maturity varied from species to species with the males attaining maturity at a slightly lower length than the females. Breeding condition was attained mainly during the rains in Eutropius niloticus, Schilbe mystus and Siluranodon auritus and in the dry and rainy seasons in Physailia pellucida. Spawning occurred once during the breeding season in E. niloticus and S. mystus; and more than once during the prolonged breeding season in P. pellucida. Condition factors did not show any correlation with maturation of gonads. Fecundity was found to vary from species to species.     

Redescription of Electrotaenia Malopteruri (Fritsch, 1886) (Cestoda: Proteocephalidae), a Parasite of Malapterurus Electricus (Siluriformes: Malapteruridae) from Egypt

The proteocephalidean cestode Electrotaenia malopteruri (Fritsch, 1886) (Proteocephalidae: Gangesiinae), the type- and only species of Electrotaenia Nybelin, 1942 and specific to the electric catfish Malapterurus electricus Gmelin (Siluriformes: Malapteruridae), is redescribed on the basis of freshly collected material from the River Nile in Egypt. The validity of Electrotaenia is confirmed and some unique characters of this genus, observed in extensive material from different host specimens from Egypt, Sudan, Sierra Leone and Nigeria are first reported or described in detail. Such details include the internal morphology of a rostellum-like apical organ which is disc-shaped with a flat or slightly concave apex, the structure of the ovary which is follicular to reticulate, the structure of the cirrus-sac, the presence of a medio-dorsal band of muscle fibres, and the morphology of the vagina and eggs.