Septesinus gibsoni n. g., n. sp. (Monocotylidae: Heterocotylinae), from the gills of Himantura walga (Dasyatidae) off Sarawak, Borneo

Septesinus gibsoni n. g., n. sp. (Monocotylidae: Heterocotylinae) is described from the gills of the dwarf whipray Himantura walga (Müller & Henle) collected in marine waters off Sarawak (Borneo), Malaysia. Septesinus n. g. is distinguished from other genera in the Monocotylidae by a combination of characters, including a haptor with one central and seven peripheral loculi, the presence of a highly sinuous ridge surmounting all haptoral septa, four rounded accessory structures on the dorsal surface of the haptor, and the anterior region with two pairs of anteromedian and three pairs of anterolateral gland-duct openings. Septesinus n. g. is accommodated in the Heterocotylinae. Septesinus gibsoni n. sp. is described and fully illustrated, and a key to the genera of Heterocotylinae is provided. The composition of the ridges surrounding the mouth of a number of heterocotyline species and their usefulness as a taxonomic character are examined. The identity of four specimens of Monocotyle Taschenberg, 1878, also recovered from the gills of this host species, is discussed.     

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).     

Dendromonocotyle lasti n. sp. from the skin and Monocotyle caseyae n. sp. (Monogenea: Monocotylidae) from the gills of Himantura sp. (Dasyatidae) in Moreton Bay, Queensland, Australia

Seven specimens of rays of the genus Himantura which could not be identified to species were collected from waters near Dunwich, Stradbroke Island, Moreton Bay, Queensland, Australia. The five smallest specimens of Himanturasp. (disc width 218-302 mm; four female, one male) had a banded tail and the dorsal surface was uniformly grey/brown. The two largest individuals of Himantura sp. (disc widths 460, 533 mm; female and male, respectively) also had a banded tail but the grey/brown dorsal surface had white spots. Two new monogenean species (Monocotylidae: Monocotylinae) are described from both the plain and white-spotted specimens of Himantura. Dendromonocotyle lastin. sp. is distinguished from other species in the genus by the number of papillae on the haptor, by the morphology of the male copulatory organ and by the morphology of the proximal portion of the vagina. The muscular sheath which surrounds the male copulatory organ is also unique having sclerotised spines at the distal end. Dendromonocotyle species are skin parasites, but a total of five juvenile specimens of D. lasti were found on the gills of four rays. Monocotyle caseyae n. sp. from the gills is characterised by the morphology of the male copulatory organ and its accessory piece. One specimen of M. spiremae Measures, Beverley-Burton & Williams, 1990, originally described from the gills of Himantura fai Jordan & Seale off Heron Island, Great Barrier Reef, Queensland, Australia, was also found on the gills of one Himantura specimen. The site and host-specificity of the parasites and the identity of the hosts are discussed.     

Notomegarhynchus navonae n. gen. and n. sp. (Eucestoda: Tetraphyllidea), from skates (Rajidae: Arhynchobatinae) in the southern hemisphere

Notomegarhynchus n. gen. (Eucestoda: Tetraphyllidea) is proposed to accommodate Notomegarhynchus navonae n. gen., n. sp. from Atlantoraja castelnaui in Mar del Plata, Argentina. Notomegarhynchus shetlandicum n. comb. from Bathyraja eatonii and B. maccaini in South Shetlands region, Antarctica, is a second species in the genus. Notomegarhynchus belongs to the Echeneibothriinae within the Phyllobothriidae. It can be distinguished from all other tetraphyllidean genera by the structure of the scolex in form of a massive myzorhynchus consisting of a proscolex and an apical organ, both of which are nonretractable and noninvaginable; in addition, there are 4 pedunculated and nonloculate acetabula. Notomegarhynchus shetlandicum is differentiated from N. navonae particularly in details of acetabular and myzorhynchus morphology, arrangement of testes, and shape of eggs. The inclusion of Notomegarhynchus in the Echeneibothriinae requires emendation of the diagnosis of the subfamily to include taxa possessing postvaginal testes. In addition, new terminology is proposed for distinct regions of the scolex.     

Kannaphallus leptosomus n. sp. (Monogenea: Heteraxinidae: Cemocotylinae) parasitizing Scyris indica (Carangiformes: Carangidae) from Malaysia

Systematic Parasitology - A new monogenean species, Kannaphallus leptosomus n. sp., from the gills of the diamond trevally, Scyris indica Rüppell, caught off Terengganu, Peninsular Malaysia is...     

Margolisianum bulbosum n. gen., n. sp. (Nematoda: Philometridae) from the southern flounder, Paralichthys lethostigma (Pisces: Bothidae), in Mississippi Sound, USA

A new species of a philometrid nematode, Margolisianum bulbosum, is described from the subcutaneous tissue in the mouth (larvigerous females), head (males, ovigerous, and larvigerous females), and eye (preovigerous females) of the southern flounder, Paralichthys lethostigma, from Mississippi Sound. It is placed in a new genus diagnosed by the combination of 8 large, paired but separate cephalic papillae; no inner cephalic papillae; an esophagus with a separate, muscular anterior bulb; a prominent mononuclear esophageal gland; and variable, irregularly distributed cuticular bosses in the females, as well as a vestigial rectum, particularly in larvigerous females. Some female specimens exhibit rows of lateral grooves and longitudinal ridges near the posterior end. Males have 2 small slightly subequal spicules, a barbed gubernaculum, 4 pairs of small cephalic papillae, and a bipartite hypodermal extension within a membranous cuticle on the posterior end. Males, ovigerous females, and larvigerous females appear to be present year round in this sporadic infection in Mississippi.     

Duplaccessorius andinus n. gen., n. sp. (Dactylogyridae: Ancyrocephalinae) from the gills of Percichthys trucha (Perciformes: Percichthyidae) in Patagonia, Argentina

During a parasitological survey of Patagonian freshwater fishes, specimens of a new species of Monogenea were collected from the gills of Percichthys trucha (Perciformes: Percichthyidae). This species is described as the only member of a newly proposed genus of Ancyrocephalinae. Duplaccessorius n. gen. (Dactylogyridae, Ancyrocephalinae) is characterized by hooks with 2 subunits, gonads in tandem, a coiled male copulatory organ with counterclockwise rings, an accessory piece formed by 2 distinct parts, and a nonsclerotized sinistrolateral vagina with a funnel shape vestibule. Duplaccessorius andinus n. sp. infects the gills of P. trucha (Cuvier and Valenciennes, 1840) from Andean Patagonian lakes, being the first species of Ancyrocephalinae described from a South American percichthyid.     

Calicotyle californiensis n. sp. and Calicotyle urobati n. sp. (Monogenea: Calicotylinae) from elasmobranchs in the Gulf of California

Two new species of Calicotyle (Monocotylidae: Calicotylinae) are described from elasmobranchs in the western Gulf of California. Calicotyle californiensis n. sp. is described from a single specimen collected from a gray smoothhound shark (Mustelus californicus, Carcharhiniformes: Triakidae). It is distinguished from its congeners by the combination of having vaginal pores opening within the intercecal space, distal regions of the vaginae twisting, proximal regions of the vaginae fusing medially to form a kidney bean-shaped structure, and a relatively long male copulatory organ recurving 3 times and passing between the distal penis bulb and the seminal vesicle. Calicotyle urobati n. sp. is described from 16 specimens collected from at least the cloaca and rectum of the round rays Urobatis halleri and Urobatis maculatus (Rajiformes: Urolophidae). It is distinguished from its congeners by the combination of having vaginal pores opening outside the intercecal space and proximal regions of the vaginae terminating at the level of the ceca. Members of Calicotyle have not been reported previously from the eastern Pacific Ocean or from these hosts. In the past, species of Calicotyle have been distinguished based primarily on the shape and length of the male copulatory organ and hamuli. Divisions of the vaginae and the positions of the vaginal pores are also useful in distinguishing members of the genus.     

New species of Philocorydoras Suriano, 1986 (Monogenoidea: Dactylogyridae): Philocorydoras maltai n. sp., Philocorydoras beleniensis n. sp. and Philocorydoras alcantarai n. sp. from the gills of callichthyids (Siluriformes: Callichthyidae) from the Peruvian Amazonia

Systematic Parasitology - During a research on gills ectoparasites of callichthyids fishes from the Peruvian Amazonia, the following new monogenoideans species were recovered: Philocorydoras maltai...     

Albionella fabricii n. sp. (Copepoda: Lernaeopodidae) from the gills of Centroscyllium fabricii from the Northwest Atlantic

Albionella fabricii n. sp. is described from the gills of the black dogfish Centroscyllium fabricii caught off the west coast of Newfoundland. Morphological differences are found in all the female and male appendages between Albionella fabricii n. sp. and A. centroscyllii, another species occurring concurrently on the same host. Female A. fabricii n. sp. can easily be distinguished from its four congeners by the length and structure of the second maxillae and the length of the uropods. A comparison between Albionella fabricii n. sp. and identifiable females of the genus Lernaeopoda is necessary, since both genera differ mainly in the morphology of the male. Two specific characteristics, the number of secondary denticles on the claw of the maxilliped and the number of setae on the exopod of the first maxilla, distinguish females of Albionella from those of Lernaeopoda.     

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.     

Myxobolus goensis n. sp. (Myxozoa, Myxosporea, Myxobolidae), a parasite of the gills of Mugil cephalus (Osteichthyes, Mugilidae) from Goa, India

Two species of Myxobolus are reported from the gills of Mugil cephalus collected at Goa, India: M. goensis n. sp. and M. parvus Shulman, 1962. Myxobolus goensis n. sp. forms digitiform or rounded plasmodia between the gill rakers. Their spores are oval in frontal view, with tapered anterior extremity, and lemon-shaped in lateral view, measuring 9.7 (9.5-10.5) microm in length, 6.6 (6-7.5) microm in width, and 5.2 (5-6) microm in thickness. The polar capsules are pyriform and unequal in size. The larger ones are 5.3 (4.5-6) microm long and 2.4 (2-3) microm wide; the smaller ones are 2.4 (2-3) microm long and 1.8 (1.5-2) microm wide. The polar filament forms five turns aligned perpendicularly to the longitudinal axis of the larger polar capsules. Within the smaller polar capsules the polar filament is difficult to observe and, apparently, forms three coils. The spores are distinctly different from other Myxobolus species infecting M. cephalus and other Mugil spp. Furthermore, the present material is also different from 204 Myxobolus species presenting differently sized polar capsules, representing nearly all the known species with this characteristic. The fact that only the M. cephalus specimens were infected among a sample of 206 fish specimens, comprising 27 different species, strongly suggests that this parasite is specific to M. cephalus.     

A new species of marine leech (Hirudinida: Piscicolidae) from giant kelpfish, Heterostichus rostratus Girard, in southern California

Collections of giant kelpfish at inner Cabrillo Beach, San Pedro, California revealed the presence of an undescribed species of Heptacyclus, described here as Heptacyclus cabrilloi n. sp. The leech is small, only up to 14 mm total length including suckers; it has 2 pair of slightly crescentiform eyes on the oral sucker, 1 pair of punctiform ocelli on the second annulus of the trachelosome, 13 pairs of punctiform ocelli dorsally and ventrally on the urosome, and 14 marginal punctiform ocelli on the caudal sucker. Pigmentation is yellowish-tan with an unpigmented mid-dorsal stripe on both trachelosome and urosome, and with unpigmented halos around eyespots and urosome ocelli. Male reproductive system with 5 pairs of large, spherical testisacs. Mycetomes present, accessory gland cells on atrial cornu absent. Prevalence was 24.1% in June, 2011 with a range of 1-2 leeches per fish and 25.8% in October, 2011 with a range of 1-6 leeches per fish.     

Glossomastix chrysoplasta n. gen., n. sp. (Pinguiophyceae), a new coccoidal, colony-forming golden alga from southern Australia

Glossomastix chrysoplasta gen. et sp. nov. is described from cultures isolated from sandstone rubble, Sorrento Back Beach, Mornington Peninsula, Victoria, Australia. The alga forms wall‐less, coccoidal vegetative cells that congregate in mucilaginous colonies and reproduce by successive bipartition. Plastids have girdle lamellae and partially embedded pyrenoids that are traversed by cytoplasmic channels. Zoospores are uniflagellate and swim poorly; a narrow lingulate pseudopod provides their primary form of motion. The single flagellum, which lacks hairs, a flagellar swelling, and autofluorescence, is the equivalent of the posterior flagellum in other golden algae. The anterior flagellum is absent; the basal body with which it would normally be associated is blind. The flagellar apparatus has two basal bodies, three microtubular roots, and a rhizoplast. The posterior (elder) basal body has a transitional helix that is proximal to the basal plate. Glossomastix chrysoplasta, placed in the Pinguiophyceae on the basis of molecular sequence and biochemical data, shares some ultrastructural features with other members of the class, especially Polypodochrysis teissieri, which has similar zoospores, but it also differs from other pinguiophytes in many respects. Glossomastix chrysoplasta is the pinguiophyte with, on average, the largest cells (exclusive of external materials), and it is the only one with a colonial habit.     

Henneguya sebasta sp. n. (protozoa, myxosporida) from California rockfish, Sebastes spp.

Henneguya sebasta sp. n. was found on the bulbus and truncus arteriosus and in the heart chambers of 7 species of marine rockfish, Sebastes, from central and southern California. The incidence of this parasite may be of economic interest to the sport and commercial fisheries because of its possible pathogenicity.