Neotropical Monogenoidea. 52. Diechodactylus joaberi n. g., n. sp. from the banded knifefish Gymnotus carapo (Gymnotiformes: Gymnotidae) in southeastern Brazil

Diechodactylus joaberi n. g., n. sp. is described from the body surface of the banded knifefish Gymnotus carapo L. (Gymnotiformes: Gymnotidae) from southeastern Brazil. The new genus is proposed to accommodate species with five pairs of hooks in anterior bilateral clusters on the haptor, three pairs of hooks in a single cluster on the posterior margin of the haptor, sclerites R1 associated with the superficial bar, and confluent intestinal caeca. The presence of five pairs of hooks in two bilateral clusters anterior in the haptor permits the differentiation of species of Diechodactylus from species of all known genera of the Gyrodactylidae. The genus is likely a member of a clade of the Gyrodactylidae comprising genera with a similar hook distribution.     

Mariauxiella pimelodi n. g., n. sp. (Cestoda: Monticelliidae): a parasite of pimelodid siluroid fishes from South America

Mariauxiella pimelodi n. g., n. sp. (Cestoda, Monticelliidae, Othinoscolecinae) is described from the South American siluriform fishes Pimelodus ornatus and Pimelodus sp. caught in Brazil and Paraguay. When compared with other genera of South American monticelliids, the new genus exhibits the following morpho-anatomical characters: the particular development of the distal circular musculature of the suckers acting as a sphincter; the medullar ovary projecting numerous lobules into the dorsal cortex; and the uterus situated in the ventral cortex but with numerous outgrowths penetrating the medulla and reaching the dorsal cortex in pregravid proglottids. The new species is the fourth monticelliid cestode recorded from Pimelodus.     

Neotropical Monogenoidea. 49. Four new species of the Diplectanidae (Dactylogyrinea) from the gills of some pachyurines (Teleostei: Sciaenidae) from the Rio Tocantins and Rio Doce Basins, with the proposal of Anoplectanum n. g. and Spinomatrix n. g.

Four new species of the Diplectanidae from the gills of freshwater sciaenid species (Pachyurinae) in Brazil are described and two new genera, Anoplectanum n. g. and Spinomatrix n. g., are proposed. These are: Diplectanum copiosum n. sp. from Pachyurus junki and Petilipinnis grunniens; Anoplectanum haptorodynatum n. g., n. sp. from Pachyurus junki and Petilipinnis grunniens, and A. microsoma n. g., n. sp. from Petilipinnis grunniens, all in the Tocantins Basin; and Spinomatrix penteormos n. g., n. sp. from Pachyurus adspersus in the Rio Doce Basin. Anoplectanum is proposed to accommodate diplectanids lacking squamodiscs and having a superficial root of the ventral anchor as long or longer than the deep root. Spinomatrix is proposed for species having a haptoral and peduncular armature composed of spines, hooks, anchors, squamodiscs and armed muscular pads.     

Neotropical Monogenoidea. 33. Three new species of Ancistrohaptor n. g. (Dactylogyridae,Ancyrocephalinae) on Triportheus spp. (Teleostei,Characidae) from Brazil,with checklists of ancyrocephalines recorded from neotropical characiform fishes

Three new species of Ancistrohaptor n. g. are described from the gills of three species of Triportheus (Characidae) collected from the environs of Manaus, Amazonas, Brazil: A. falcatum n. sp. from T. elongatus; and A. falciferum n. sp. and A. falcunculum n. sp. from T. angulatus, T. albus and T. elongatus. Ancistrohaptor n. g. is proposed for species possessing overlapping gonads, a dextral or dextroventral vaginal aperture, a coiled (counter-clockwise) male copulatory organ, two accessory pieces in the copulatory complex, and a haptor armed with two pairs of anchors (ventral anchor with elongate shaft), dorsal and ventral bars and 14 hooks; hook pair 1 (ventral) anterior to ventral bar, pairs 2–4 (ventral) lying bilaterally anterior to ventral anchor bases, pair 5 (ventral) associated with distal end of ventral anchor shafts, and pairs 6 and 7 (dorsal) bilateral about midway along haptoral length. Parasite-host and host-parasite lists of the Ancyrocephalinae from neotropical Characiformes are provided.     

Diplectanids infesting the gills of the barramundi Lates calcarifer (Bloch) (Perciformes: Centropomidae), with the proposal of Laticola n. g. (Monogenoidea: Diplectanidae)

Four species of the Monogenoidea, Laticola lingaoensis n. sp., L. latesi (Tripathi, 1957) n. comb. [previously Pseudorhabdosynochus latesi (Tripathi, 1957) Kritsky & Beverley-Burton, 1986], L. paralatesi (Nagibina, 1976) n. comb. [previously Diplectanum paralatesi Nagibina, 1976] and Diplectanum penangi Liang & Leong, 1991, are reported from the gills of Lates calcarifer (Centropomidae) from the South China Sea (new geographical records for L. latesi and D. penangi). Collections from off Bathurst Island, Northern Territory, Australia, represent a new geographic record for L. paralatesi; Chilka Lake, Orissa, India, is established as the type-locality for L. latesi. Laticola n. g. (Diplectanidae) is proposed for species with a spoon-shaped copulatory organ with two to four concentric incomplete ridges in the base. Laticola lingaoensis, the type-species of Laticola, is described, and L. latesi and L. paralatesi are redescribed based on specimens from the South China Sea. Pseudorhabdosynochus monosquamodiscusi Balasuriya & Leong, 1995 and Pseudorhabdosynochus yangjiangenesis Wu & Li, 2005 are considered junior subjective synonyms of L. latesi and L. paralatesi, respectively.     

Neotropical Monogenoidea: Euryhaliotrema dontykoleos n. sp. (Dactylogyridae) from the gills of the freshwater sciaenid, Pachyurus junki (Perciformes)

Euryhaliotrema dontykoleos n. sp. (Monogenoidea, Polyonchoinea, Dactylogyridae) is described based on specimens collected from the gills of Pachyurus junki (Teleostei, Sciaenidae, Pachyurinae) in the Rio Tocantins and its tributaries, State of Tocantins, Brazil. The new species, the first species of Monogenoidea reported from a pachyurine, is easily differentiated from its congener by the presence of toothlike projections in the border of the vaginal opening and by having a trapezoidal anteromedial projection on the ventral bar. Phylogenetic analysis indicates that the new species is not a member of the clade that includes the Euryhaliotrema spp. from Plagioscion spp., a second lineage of freshwater sciaenids in South America. Euryhaliotrema dontykoleos shares an immediate ancestor with the clade formed by parasites infecting marine Paralonchurus spp., (Sciaenidae), and those of Plagioscion spp.     

Neotropical Monogenoidea. 43. Diplectanum monticellii n. sp. (Diplectanidae) from the gills of Cynoscion leiarchus (Perciformes: Sciaenidae) in Brazil

Diplectanum monticellii n. sp. is described from the gills of Cynoscion leiarchus, a marine Sciaenidae, from Itacuru?á, Rio de Janeiro (type locality); Baía de Guaratuba, Paraná; and Pontal do Sul, Paraná in Brazil. The new species is characterized by the following features: bell-shaped male copulatory organ with a sleevelike base, accessory piece absent, vas deferens looping left intestinal cecum, vaginal aperture sinistroventral, and ventral anchor with elongate superficial and deep roots.     

Diplectanids infesting the gills of the barramundi Lates calcarifer (Bloch) (Perciformes: Centropomidae), with the proposal of Laticola n. g. (Monogenoidea: Diplectanidae)

Four species of the Monogenoidea, Laticola lingaoensis n. sp., L. latesi (Tripathi, 1957) n. comb. [previously Pseudorhabdosynochus latesi (Tripathi, 1957) Kritsky & Beverley-Burton, 1986], L. paralatesi (Nagibina, 1976) n. comb. [previously Diplectanum paralatesi Nagibina, 1976] and Diplectanum penangi Liang & Leong, 1991, are reported from the gills of Lates calcarifer (Centropomidae) from the South China Sea (new geographical records for L. latesi and D. penangi). Collections from off Bathurst Island, Northern Territory, Australia, represent a new geographic record for L. paralatesi; Chilka Lake, Orissa, India, is established as the type-locality for L. latesi. Laticola n. g. (Diplectanidae) is proposed for species with a spoon-shaped copulatory organ with two to four concentric incomplete ridges in the base. Laticola lingaoensis, the type-species of Laticola, is described, and L. latesi and L. paralatesi are redescribed based on specimens from the South China Sea. Pseudorhabdosynochus monosquamodiscusi Balasuriya & Leong, 1995 and Pseudorhabdosynochus yangjiangenesis Wu & Li, 2005 are considered junior subjective synonyms of L. latesi and L. paralatesi, respectively.     

Two amphistomes,Lobatodiscus australiensis n.g., n.sp. and Elseyatrema microacetabularis n.g., n.sp., from the Australian turtle Elseya dentata (Gray)

Summary Lobatodiscus australiensis n.g., n.sp. (family and subfamily uncertain) and Elseyatrema microacetabularis n.g., n.sp. (family Paramphistomidae, subfamily Dadaytrematinae?), from the intestine of the freshwater turtle Elseya dentata (Gray) in Queensland, Australia, are described. Lobatodiscus has a large lobed acetabulum, small oral diverticula which do not protrude out of the oral sucker, two pairs of lymph vessels and no oesophageal bulb. Elseyatrema has a small acetabulum, large protruding oral diverticula, an oesophageal bulb, juxtaposed testes, one pair of rudimentary lymph vessels and no cirrus-sac. ac]19830626     

Mode of transmission, host switching, and escape from the Red Queen by viviparous gyrodactylids (Monogenoidea)

Compared to other monogenoidean groups, viviparous gyrodactylids exhibit extraordinary species diversity and broad host range. It has been suggested that this evolutionary success is associated with a suite of morphological and life-history traits that include, in part, continuous transmission (i.e., ability to infect new hosts throughout the gyrodactylid life cycle). Experiments were conducted to explore the putative adaptive advantage of continuous transmission within viviparous gyrodactylids during colonization of new host resources. Differences in infrapopulation growth, such as abundance, prevalence, and duration of the infection, of Gyrodactylus anisopharynx on 3 species of fish--Corydoras paleatus and Corydoras ehrhardti (both natural hosts) as well as Corydoras schwartzi (a host not known to harbor G. anisopharynx)--held under isolated and grouped conditions were determined. Results showed that infrapopulations of G. anisopharynx on C. paleatus and C. schwartzi had higher growth when the parasite had the opportunity for host transfer (grouped hosts). Infrapopulations of G. anisopharynx on isolated and grouped C. ehrhardti showed an opposite trend, although differences in mean duration and maximum abundance were not statistically different. Results obtained from experiments with C. paleatus and C. schwartzi support the hypothesis that continuous transmission in viviparous gyrodactylids enhances colonization success, probably by allowing initial avoidance of Red Queen dynamics. The absence of statistical differences between infrapopulations on isolated and grouped C. ehrhardti suggests that parasite dynamics may be influenced by factors other than continuous transmission in this host.     

Acugutturus parasiticus n.g., n.sp., a remarkable ectoparasitic aphelenchoid nematode from Periplaneta americana (L.), with proposal of acugutturinae n.subf.

Summary Acugutturus parasiticus n.g., n.sp. is described from St. Lucia, W. Indies. The species is unique in the Aphelenchoidea because of the 50 to 60 μm stylet with the conus much longer than the shaft. A. parasiticus is ectoparasitic on Periplaneta americana (L.), all stages of the nematode, including the egg, being found on the body surfaces. Acugutturinae n.subf. is proposed to accommodate the new genus.     

Kritskyia moraveci n. g., n. sp. (Monogenea: Dactylogyridae) from the urinary bladder and ureters of Rhamdia quelen (Quoy & Gaimard, 1824) (Pisces: Pimelodidae) in Brazil

Kritskyia n. g. is proposed for K. moraveci n. sp. from the urinary bladder and ureters of Rhamdia quelen (Quoy & Gaimard, 1824), a pimelodid fish from the reservoir of the Hydroelectric Power Station of Passo Fundo, Rio Grande do Sul State, Brazil. The new genus is most closely related to Acolpenteron Fischthal & Allison, 1940, from which it differs by having a male copulatory complex composed of a coiled cirrus and a bipartite accessory piece, a sinistral vagina, and an antero-ventrally concave haptor which possesses 14 ventrally directed marginal hooks, but lacks an anterior rim and 4A hooks.Research fellow Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq, Brasil.     

Gibbsia archiuli (Apicomplexa, Eucoccidiorida) n. g., n. sp. from the Millipede Archiulus moreleti

ABSTRACT. Gibbsia archiuli n. g., n. sp. (Eucoccidiorida, Adeleidae) is named for the apicomplexan protozoon described by Gibbs (1952) from the blood cells of the South African garden millipede Archiulus moreleti. Merogony, gamogony, and sporogony all take place in the host's blood cells. The oocysts contain four sporocysts, each with one sporozoite. The microgametes are not flagellated.     

A new pleuropholid, Gondwanapleuropholis longimaxillaris n. g., n. sp. (Actinopterygii: Teleostei) from the Jurassic of north east Brazil

A basal teleost fish is described for the first time from the Upper Jurassic Pastos Bons Formation, Parnaíba Basin, northeastern Brazil. This new material is identified as a new genus and a new species, Gondwanapleuropholis longimaxillaris. This taxon shares a number of synapomorphies with the pleuropholids. The family Pleuropholidae is confirmed as member of the Teleostei.     

Monogeneans from the gills of glassfishes (Teleostei: Perciformes: Ambassidae) in India, with the proposal of Chandacleidus n. g. (Monogenea: Dactylogyridae)

Chandacleidus n. g. (Monogenea, Dactylogyridae) is proposed to include three species collected from the gills of Indian glassfishes (Ambassidae): Chandacleidus recurvatus (Jain, 1961) n. comb. (syn. Urocleidus recurvatus Jain, 1961) from Chanda nama and C. ranga (new host record) is redescribed; and Chandacleidus saiensis n. sp. and C. lucknowensis n. sp., both from Chanda nama and C. baculis, are described. Chandacleidus n. g. is characterised by species possessing: posteriorly united intestinal caeca; overlapping gonads (testis dorsal to ovary); a counterclockwise male copulatory organ; a grooved accessory piece; a dextro-marginal vaginal pore; a haptor with two lateral flaps and armed with dissimilar dorsal and ventral anchor/bar complexes and 14 similar hooks (dissimilar in size); and hook shanks comprised of two subunits.     

Nilobathynella predynastica n.g., n.sp. (Crustacea:Bathynellacea) from the Nile valley in Nubia

Nilobathynella predynastica n.g., n.sp. from Abri, Nubia, is the first representative of the Tribus Cteniobathynellini in the Nile Valley. Its relationship with the other Cteniobathynellini, as well as its biogeographical significance, are briefly discussed.     

Pseudolernentoma brasiliensis n. g., n. sp. (Copepoda: Poecilostomatoida: Chondracanthidae) parasitic on Genypterus brasiliensis (Osteichthyes: Ophidiidae) from off the State of Rio de Janeiro,Brazil

Pseudolernentoma, a new chondracanthid genus was proposed to accommodate Pseudolernentoma brasiliensis n. g., n. sp., parasitic on the pink cusk-eel Genypterus brasiliensis Regan, from off the coast of Rio de Janeiro, Brazil. The new genus can be differentiated from the other genera of the Chondracanthidae by the presence of an inflated head with lateral expansions and anteroventral bifurcate processes on the trunk.     

Amapacanthus amazonicus n. g., n. sp. (Acanthocephala: Diplosentidae: Allorhadinorhynchinae) from Arius passany and Anableps microleps (Pisces) at Maraca Island off northern Brazil

Amapacanthus amazonicus n. g., n. sp. is described from the intestine of Arius passany (Valenciennes) and Anableps microleps Müller. The most important diagnostic features are: a small globular proboscis armed with 6 diagonal rows of 3 stout hooks; middle hooks conspicuously stouter and larger than anterior ones; terminal hooks as long as middle hooks but straighter and more slender; a double-walled proboscis receptacle; a trunk bearing spines anteriorly; and two tubular cement glands in the males. Amapacanthus n. g. is differentiated from Allorhadinorhynchus, Golvanorhynchus and Slendrorhynchus, the other genera of the Allorhadinorhynchinae, by the presence of a globular proboscis armed with a small number (18) of hooks. A key to the species of the Allorhadinorhynchinae is presented.     

Monodelphoxyuris dollmeiri n. g., n. sp. (Nematoda: Oxyurida) from Monodelphis emiliae in Peru

Monodelphoxyuris dollmeiri n. g., n. sp. is described from the caecum of Monodelphis emiliae (Thomas) (Marsupiala: Monodelphidae) collected in the eastern region of the Andes of Peru. M. dollmeiri n. sp. differs from the closest pinworm described from marsupials in the Neotropics (Didelphoxyuris thylamisis Gardner & Hugot, 1995) in having operculate eggs and males that possess a tip prolonged of tail and a different kind of area rugosa. Several other species of pinworms have been described from marsupials in Australia, but all are characterised by possessing of a buccal capsule that is strongly cuticularised with interradial lamellae. These structures are lacking both in M. dollmeiriandD. thylamisis. Monodelphoxyuris n. g. is characterised by a mouth opening into a depression and lateral alae composed of two longitudinal crests. Males possess an area rugosa composed of six ventral sagittal mamelons, a caudal extremity prolonged by a robust tip of the tail which is directed backwards, four pairs of genital papillae (two pairs lateral adanal and sessile, one pair just posterior to the spicule aperture, and the last pair at posterior extremity and pedunculate). Females possess an opisthodelphic uterus, a reflected ovary and operculate, unembryonated, oval eggs.