Trypanosoma humboldti n. sp. from the Chilean Catshark,Schroederichthys chilensis (Guichenot, 1848)1

The morphology of Trypanosoma humboldti n. sp. is described from living and stained specimens obtained from the blood of a catshark, Schroederichthys chilensis. This represents the first report of a trypanosome in fish from the eastern Pacific Ocean. It is distinguished by its size and apparent lack of pleomorphism. The presence of a leech, Branchellion ravenellii, attached to the catshark, raises the possibility that it can act as a vector. Additionally, this leech is recorded for the first time from the Pacific Ocean.     

Seasonal variability of gillnet selectivity in Chilean hake Merluccius gayi gayi (Guichenot, 1848)

This study examines the seasonal variability in gillnet size selectivity for the main Chilean hake (Merluccius gayi gayi) fishery off the coast of central Chile. Selectivity estimates were based on five gillnet mesh sizes (50, 60, 70, 80, 90 mm) in four traditional fishing areas, and during periods of low and high reproductive activity. Average fish length caught in the earlier period (low reproductive activity) was 30.8 cm LT (±4.17), and significantly longer (p < .05) at 35.9 cm TL (±6.15) in the latter period (high reproductive activity). For males, the selectivity factor was similar in both periods, thus the estimated modal lengths did not differ seasonally (p > .05). For females, however, both the selectivity factor and the estimated modal lengths changed significantly depending on the time of year (p < .05). A significant increment was estimated in the girth/perimeter ratio and condition factor during the period of higher reproductive activity. This change in the fish girth of females during spawning helps explain the significant reduction in their selectivity factor estimates in August–October.     

Gillnet selectivity for Chilean hake (Merluccius gayi gayi Guichenot, 1848) in the bay of Valparaíso

To determine the selectivity of gillnets in the Chilean artisanal fishery for the Chilean hake Merluccius gayi gayi, an experimental net was used with three mesh sizes (5.2, 6.8 and 7.6 cm). A total of 2279 specimens of Chilean hake were caught (24–56 cm total length, TL), mainly via gilling and snagging. The catch proportion below the size of sexual maturity SSM_50% (37 cm TL) for each mesh size tested was estimated. Models were fitted separately according to the sex to compensate for differences in size compositions, with the males fitted to a binormal model and females fitted to the normal location model. Analysing both sexes combined, the model with the lowest deviance was lognormal, with estimated modal lengths of 30.9, 40.2 and 43.9 cm TL for meshes of 5.2, 6.8 and 7.6 cm, respectively. The estimated selectivity factor (SF) indicates that the modal size matches the SSM_50% with a mesh size of 6.2 cm, while the length of retention of 50% (l₅₀) coincides with the SSM_50% with a mesh size of 7.6 cm.     

Lernaeopoda tenuis n. sp. andPseudolernaeopoda caudocapta n. g., n. sp. (Copepoda,Lernaeopodidae) parasitic onTriakis maculata (Kner & Steindachner) from the Chilean coast,South Pacific

Summary One new genus and two new species of the Lernaeopodidae (Copepoda: Siphonostomatoida), parasitic onTriakis maculata off the coast of Chile, are described and illustrated. The new genus,Pseudolernaeopoda, parasitizes the cloaca of its host. Its type-species,P. caudocapta, can be distinguished fromLernaeopoda by the absence of modified uropods. A new species ofLernaeopoda, L. tenuis, was found on the gills of the same host. In absence of the male, the generic affinities of this species must be considered only tentative. ac]19850409     

Diarthrodella chilensis sp.n. und Rossopsyllus kerguelenensis quellonensis subsp.n. (Copepoda, Paramesochridae) von Chile

During a collecting trip to Chile, two species of Paramesochridae belonging to the genera Diarthrodella and Rossopsyllus were found. The new species D. chilensis is widely distributed on the coasts of central Chile. Up to now, the new subspecies R. kerguelenensis quellonensis is only known from Quellón, Island of Chiloé. The nominate subspecies R. kerguelenensis kerguelenensis Soyer, 1974 was described from the Kerguelen Archipelago.     

Two newCandida species:Candida chilensis sp.n. andCandida valdiviana sp.n.

Two new nitrate-assimilating yeasts isolated from decomposed wood ofNothofagus sp. are described. The namesCandida chilensis andCandida valdiviana are proposed.A table is given of the assimilation and fermentation reactions of the currently acceptedCandida species that use nitrate as the sole source of nitrogen.Candida koshuensis was not validly described so the nameCandida boidinii must be accepted for this species.The work done at the Universidad Austral de Chile had financial support of the Comisión Nacional de Investigatión Científica y Technológica (Proyecto No. 151).     

Ogmogaster heptalineatus n.sp. (Trematoda: Notocotylidae) from the Chilean sea lion Otaria flavescens

Summary Ogmogaster heptalineatus n.sp. is described from the Chilean sea lion Otaria flavescens. Distinct characteristics of the species are: presence of 7 longitudinal ridges on the ventral surface, cirrus armed with scales, testes and ovary deeply lobed and eggs circular with short polar filaments. This is the first report of the genus Ogmogaster from South America and the first report of Otaria flavescens as a host for this genus. ac]19820320     

On two members of the family Lernaeopodidae (Crustacea: Copepoda) parasitic on elasmobranchs in Chilean waters,with a description of Pseudocharopinoides myliobatidos n. g., n. sp. from Myliobatis chilensis Philippi

Pseudocharopinoides myliobatidos n. g., n. sp. (Lernaepodidae) is described. Although similar to Pseudocharopinus Kabata, 1964, it differs from this genus in the ventral position of its posterior processes and by its non prehensile second antenna. The similarity indicates that it belongs to the Charopinus-branch of the Lernaeopodidae. In addition, Brianella corniger Wilson, 1915 is recorded on Sympterigia brevicaudata and is redescribed. ac]19861103     

Pseudascarophis genypteri n. sp. (Nematoda: Cystidicolidae) parasite from the red ling Genypterus chilensis off Chile.

A new nematode belonging to the Cystidicolidae is described, Pseudascarophis genypteri n. sp. was found in the intestine of the red ling Genypterus chilensis, sampled off Talcahuano, Chile. It is distinguished from Ascarophis species mainly by the absence of cephalic papillae and of submedial and medial labia. The other species in the genus, Pseudascarophis kyphosi Ko, Margolis, and Machida, 1985, found in Kyphosus cinerascens, and P. tropica (Solov'eva, 1996), found in Parupeneus chrysopleuron, differed principally from P. genypteri in the form of pseudolabia, number of pre- and postanal papillae, and length of spicules.     

Trypanosoma pifanoi n. sp. from Colombian Bats*

SYNOPSIS. A new large trypanosome was found in the blood of 19 Artibeus lituratus and 2 Phyllostomus hastatus bats. The monomorphic trypanosome resembles Trypanosoma megadermae in some respects, but differs from it in that it is larger and has a short flagellum, both extremities are very tapered, the kinetoplast is very close to a small nucleus and there is a greater distance between the kinetoplast and the posterior extremity of the body. In diphasic blood-agar cultures there is a great variety of odd multiplication forms not described from other trypanosome cultures, but some simulate T. cruzi. This trypanosome is not capable of infecting mice, tissue culture cells, Carollia perspicillata bats, or triatomids, but is able to infect A. lituratus bats. Culture forms of the trypanosome inoculated intra-coelomically are pathogenic for several species of triatomids, and multiply in the hemolymph of Rhodnius prolizus, often producing forms similar to crithidiae of T. rangeli. Culture forms of the trypanosome seem to have common antigens with T. cruzi. This new species is described as Trypanosoma pifanoi.     

Trypanosoma (Megatrypanum) megachiropterorum sp. n. from the Flying Fox, Pteropus tonganus Quoy & Gaimard

SYNOPSIS. Trypanosoma (Megatrypanum) megachiropterorum sp. n. from the flying fox, Pteropus tonganus Quoy & Gaimard, from the Kingdom of Tonga, is described. The trypomastigotes measure 32 ± 1.74 (here and below S.D.) (27–37.5) × 3.6 ± 0.23 (3–4.5) μm and has a flagellum averaging in length 6.4 ± 0.92 (4.5–10) μm. Their nuclear index is 1.2 ± 0.16 (0.7–1.6) and their kinetoplastic index equals 6.2 ± 0.32 (5.5–7.1). This is the first report of a member of the subgenus Megatrypanum from bats outside the American and African continents and also the first record of a trypanosome from bats in the Pacific area.     

Choricotyle anisotremi n. sp. (Monogenea: Diclidophoridae) parasitic on Anisotremus scapularis (Tschudi) from the northern Chilean coast

Choricotyle anisotremi n. sp. is described from the gills and on the inner surface of the operculum of Anisotremus scapularis (Pomadasyidae) from the Chilean coast. Distinct characteristics of the new species are: presence of an oval accessory sclerite on the inner quadrant of the clamp adjacent to the accessory sucker; 12 genital hooks; short and stout peduncles, the last pair of which are closely apposed; a lobed seminal receptacle; and a fan-like posthaptor without a terminal lappet.     

Bonamia exitiosus n. sp. (Haplosporidia) infecting flat oysters Ostrea chilensis in New Zealand.

Bonamia sp. is a pathogenic parasite that occurs in the haemocytes of dredge oysters Ostrea chilensis Philippi in New Zealand. Ultrastructurally it resembles other haplosporidians in the possession of haplosporosomes, haplosporogenesis, persistence of mitotic microtubules during interphase and of the nuclear envelope during mitosis, and occurrence of a diplokaryotic or multi-nucleate plasmodial stage. Another stage containing a large vacuole derived from enlargement of 1 or more mitochondria has not previously been described from other haplosporidians. It most closely resembles B. ostreae Pichot et al., 1979, which parasitises and is pathogenic in haemocytes of European flat oysters, O. edulis. However, B. ostreae is smaller and denser, and has fewer lipoid bodies and haplosporosomes. We have nearly completely sequenced the small ribosomal gene of the organism from O. chilensis. Initial comparisons of these sequences with those of other protozoans showed similarities to B. ostreae. Polymorphism within Bonamia sp. was confirmed by restriction fragment length polymorphism analysis. On the basis of ultrastructural and molecular considerations it is proposed that this organism be named Bonamia exitiosus sp. nov.     

Trypanosoma kansasensis sp. n. from Neotoma floridana in Kansas

Trypanosoma kansasensis sp. n. (Sarcomastigophora: Kinetoplastida) is described from three of 23 (13%) eastern woodrats (Neotoma floridana) collected from Pottawatomie County, Kansas (USA). All flagellates found in the blood of woodrats were trypomastigotes and are larger than T. neotomae in overall dimensions, especially flagellar length and the distance between the posterior end of the organism and kinetoplast. Liver infusion-tryptose (LIT) cultures of infected whole blood resulted in the transformation of some parasites into epimastigotes; however, there was no apparent increase in parasite numbers.