Two new species of dactylogyrids (Monogenea: Dactylogyridae) infecting the gill filaments of fishes in the southern Peruvian Amazon.

Two new dactylogyrid species were found infecting the gill filaments of two freshwater fishes collected in the Amazon River basin around Madre de Dios, Peru, namely, Demidospermus wilveri n. sp. from Loricaria sp. (Siluriformes: Loricariidae), and Notozothecium agusti n. sp. from Brycon amazonicus (Spix & Agassiz) (Characiformes: Bryconidae). Demidospermus wilveri n. sp. is characterized by having the following combination of characteristics: (1) a male copulatory organ (MCO) with 1½ rings and a spoon-shaped distal end, (2) an accessory piece with expanded distal end, (3) dorsal and ventral bars with broadly V-shaped and expanded ends, and (4) hooks similar in size. Notozothecium agusti n. sp. differs from its ten congeners by the following combination of characteristics: (1) a coiled MCO with 1½ rings and a sinuous accessory piece with kidney-shaped distal end, (2) an rod-shaped and straight dorsal bar, (3) and anchors with robust superficial roots. Demidospermus wilveri n. sp. represents the thirty-second species in the genus, the eighth from Peru and the fifth parasitising a loricariid catfish from the Peruvian Amazon. Notozothecium agusti n. sp. is the second species of the genus described in Peru and the first species infecting a bryconid host.

A redescription of Hedruris moniezi Ibáñez & Córdova, 1976 (Nematoda: Hedruridae), an endoparasite of the Titicaca water frog Telmatobius culeus (Garman, 1876) (Anura: Telmatobiidae), with comments on all other known Hedruris species in Peru.

Hedruris moniezi Ibáñez & Córdova, 1976 (Nematoda: Hedruridae) was described using light and scanning electron microscopy (SEM) based on specimens collected from the stomach of Telmatobius culeus (Anura: Telmatobiidae) in Peru. We observed some characteristics not reported previously, including sessile and pedunculated papillae and amphid on the pseudolabia, bifid deirids, morphology of the retractable chitinous hook, morphology and arrangement of the plates on ventral surface of the posterior end of the males, and arrangement of caudal papillae. Telmatobius culeus represents a new host of H. moniezi. In addition, H. basilichtensis Mateo, 1971 is considered to be a junior synonym of H. oriestae Moniez, 1889. A key to valid species of Hedruris in Peru is provided.

Four new species of Anenterotrema Stunkard, 1938 (Digenea: Dicrocoellidae) infecting phyllostomid bats in the Peruvian Amazon.

During a research of digeneans (Platyhelminthes: Trematoda) infecting leaf-nosed bats (Chiroptera: Phyllostomidae) from the Kawsay Biological Station in Madre de Dios, southeastern Peru, four new species were described based on light and scanning electron microscopy (SEM): Anenterotrema paramegacetabulum n. sp. from the seba's short-tailed bat Carollia perspicillata Linnaeus, A. hastati n. sp., A. kawsayense n. sp., and A. peruense n. sp. from the greater spear-nosed bat Phyllostomus hastatus (Pallas). Anenterotrema paramegacetabulum n. sp. differs from all congeners by having a terminal oral sucker, a transversely elongated ventral sucker without clamp-shaped, and by having the testes located immediately posterior to ventral sucker. Anenterotrema hastati n. sp. is easily differentiated from the other congeneric species by having an almost clamp-shaped oral sucker, well-developed cirrus sac, a bilobulated seminal receptacle, and a group of well-developed unicellular glands located anterolateral to cirrus sac. Anenterotrema kawsayense n. sp. is characterized by possessing protuberances on the anterior margin of the oral sucker. Anenterotrema peruense n. sp. is mainly characterized by having the testes located principally anterior to ventral sucker and the cirrus sac located perpendicular to midline of the body. The present finding brings to 12, the number of known species of Anenterotrema. A key to the species of Anenterotrema Stunkard, 1938 is provided.

First records of marine microturbellarians (Platyhelminthes: Rhabdocoela, Fecampiida and Prolecithophora) from Peru, with the description of a new species.

The marine microturbellarian diversity is scarcely known from the Pacific coastline of South America. The coastal margin of Peru is highly influenced by cold-water currents (Humboldt Current System). These cold-water currents play important roles in shaping the marine species diversity in this area. However, there are no previous records of marine microturbellarians for Peru. Here, we describe a new species of Rhabdocoela and report on five other species of marine microturbellarians for this country. Carcharodorhynchus giaae n. sp. (Kalyptorhynchia, Schizorhynchidae), can be identified based on the configuration of the proboscis lips and the male and female genital systems. The male copulatory organ lacks a cirrus, but has a funnel-like, curved stylet with three pairs of spines along it, which distinguishes this species from its congeners. The female system has a vagina with a sclerotized, heavily coiled structure - a feature not mentioned in any known species of the same genus. In addition, we describe noteworthy features for another rhabdocoel, Trigonostomum galapagoense (Dalytyphloplanida, Trigonostomidae). Finally, we provide new records for three rhabdocoel species (Alcha evelinae, Itaipusa divae, Utelga heinckei), one species of Fecampiida (Urastoma cyprinae), and an unidentified species of Prolecithophora.

Biochemical, biological and molecular characterization of an L-Amino acid oxidase (LAAO) purified from Bothrops pictus Peruvian snake venom.

An L-amino acid oxidase from Peruvian Bothrops pictus (Bpic-LAAO) snake venom was purified using a combination of size-exclusion and ion-exchange chromatography. Bpic-LAAO is a homodimeric glycosylated flavoprotein with molecular mass of ∼65 kDa under reducing conditions and ∼132 kDa in its native form as analyzed by SDS-PAGE and gel filtration chromatography, respectively. N-terminal amino acid sequencing showed highly conserved residues in a glutamine-rich motif related to binding substrate. The enzyme exhibited optimal activity towards L-Leu at pH 8.5, and like other reported SV-LAAOs, it is stable until 55 °C. Kinetic studies showed that the cations Ca2+, Mg2+ and Mn2+ did not alter Bpic-LAAO activity; however, Zn2+ is an inhibitor. Some reagents such as ß-mercaptoethanol, glutathione and iodoacetate had inhibitory effect on Bpic-LAAO activity, but PMSF, EDTA and glutamic acid did not affect its activity. Regarding the biological activities of Bpic-LAAO, this enzyme induced edema in mice (MED = 7.8 µg), and inhibited human platelet aggregation induced by ADP in a dose-dependent manner and showed antibacterial activity on Gram (+) and Gram (-) bacteria. Bpic-LAAO cDNA of 1494 bp codified a mature protein with 487 amino acid residues comprising a signal peptide of 11 amino acids. Finally, the phylogenetic tree obtained with other sequences of LAAOs, evidenced its similarity to other homologous enzymes, showing two well-established monophyletic groups in Viperidae and Elapidae families. Bpic-LAAO is evolutively close related to LAAOs from B. jararacussu, B. moojeni and B. atrox, and together with the LAAO from B. pauloensis, form a well-defined cluster of the Bothrops genus.

Adiciones a la fauna de protozoarios de los Pantanos de Villa, Lima, Perú / Additions of protozoan to Pantanos de Villa fauna, Lima, Peru

En nueve estaciones ubicadas en los cuerpos de agua de los Pantanos de Villa, Chorrillos, Lima; fueron realizadas colectas mensuales entre octubre de 1999 y agosto del 2000. Se determinaron 128 especies de protozoarios distribuidos en 101 géneros, 69 familias y 28 reportándose. De las 128 especies, 73 especies son registros nuevos para los Pantanos de Villa, reportándose hasta la actualidad un total de 171 especies de protozoarios para este lugar. El grupo predominante fue el de los ciliados con el 61,72 por ciento de las especies registradas, seguidos por los mastigóforos con el 21,87 por ciento y los sarcodinos con el 16,41 por ciento. El grupo más abundante fué el de los mastigóforos con el 75 por ciento de los individuos seguido de los ciliados (19,5 por ciento) y sarcodinos (4,5 por ciento).