Corynosoma cetaceum in the stomach of Franciscanas, pontoporia blainvillei (Cetacea): an exceptional case of habitat selection by an Acanthocephalan

Adult acanthocephalans are typically found in the intestine of vertebrates, where they can readily absorb nutrients. However, Corynosoma cetaceum has been frequently reported in the stomach of cetaceans from the Southern Hemisphere. The ecological significance of this habitat was investigated by examining data on number, sex ratio, maturity status, biomass, and fecundity of C. cetaceum in different parts of the digestive tract of 44 franciscanas Pontoporia blainvillei. Individual C. cetaceum occurred in the pyloric stomach (PS) and, to lesser degrees, in the duodenal ampulla (DA) and the main stomach (MS). Females outnumbered males in all chambers, although the sex ratio was closer to 1:1 i…

Redescription of allencotyla mcintoshi price, 1962 (monogenea), with an emended diagnosis of allencotyla price, 1962

The original description of the type species of Allencotyla, A. mcintoshi Price, 1962, was based on 5 specimens collected from 1 amberjack Seriola lalandi in Florida. In this study, A. mcintoshi is redescribed based on new specimens collected from juvenile greater amberjacks S. dumerili captured off the Spanish Mediterranean coast and maintained in experimental culture tanks. Except for a slightly smaller size, individuals of S. dumerili were morphologically similar to the type specimens. However, reexamination of the type material and examination of the new specimens revealed the following discrepancies with respect to the original description: (1) the vaginal pore is unarmed and covered w…

La belleza del darwinismo metafísico [Ressenya]

Reseña del libro de Jorge Wagensberg "La rebelión de las formas" Tusquets Editores, barcelona, 2004, 318 p.

Are epizoites biological indicators of a western Mediterranean striped dolphin die-off?

During a die-off of Mediterranean striped dolphins Stenella coeruleoalba in 1990-91, 82 individuals stranded on the Spanish coast were examined for crustacean ectoparasites and epizoites. Six species were detected: Syncyarnus aequus, PenneUa sp., Xenobalanus globicipitis, Conchoderma virgatum, Lepas pectinata and Lepas cf. hillii. The barnacles L. pectinata and L. cf. hillii are reported here for the first time on cetaceans; they were attached to the teeth. C. virgaturn was also found on the teeth; this is an unusual attachment on cetaceans. X. globicipitis showed a higher prevalence on the dolphins studied than on those stranded in the same months before (1980 to 1990) and after (1991 to 1…

The origin of lecithodesmus (Digenea: Campulidae) based on ND3 gene comparison

Species of Lecithodesmus (Campulidae) occur almost exclusively in baleen whales throughout a wide geographical distribution. Other campulids occur only in odontocetes and, secondarily, in pinnipeds and the sea otter. Therefore, the ancestor of Lecithodesmus might have either cospeciated with mysticetes during the early divergence of mysticete and odontocete cetaceans or originated later via host switching. We evaluate both possibilities based on a phylogenetic analysis. The ND3 mitochondrial gene sequence of a species of Lecithodesmus was included in a previous partial molecular phylogeny of the Campulidae. Fasciola hepatica and Dicrocoelium dendriticum were used as outgroups. Maximum parsi…

Presence of Genital Spines in a Male Corynosoma cetaceum Johnston and Best, 1942 (Acanthocephala)

We collected 83 females and 80 males of Corynosoma cetaceum from 2 common dolphins, Delphinus delphis, collected in northern Patagonia (Argentina). Worms were most similar to specimens collected in other South American localities. However, 1 male had 2 spines adjacent to the genital pore and isolated from the rest of body spines. This finding confirms the recent reassignment of C. cetaceum to Corynosoma. Absence of genital spines is suggested to be avoided as the sole criterion to exclude specimens from Corynosoma or Andracantha. Aznar Avendaño, Francisco Javier, Francisco.Aznar@uv.es ; Raga Esteve, Juan Antonio, Toni.Raga@uv.es

Estudio biológico de la helmintofauna de la Franciscana (Pontoporia blainvillei) (Cetacea) en aguas de Argentina

Prácticas docentes para la zoología y botánica en los nuevos planes de estudio.1.

Nuestra propuesta intenta promover el uso de las TIC´s (tecnologías de la información y la comunicación) en las clases prácticas de Zoología y Botánica (dos materias obligatorias para estudiantes de 2º curso de Biología y de Ciencias Ambientales) a través del uso de un DVD interactivo que contiene los materiales para las dos sesiones prácticas, el estudio de la morfología funcional del cráneo de los mamíferos y una salida al campo virtual a un área protegida para reconocer plantas y animales comprendiendo sus relaciones ecológicas en los diferentes hábitats. En el ámbito universitario, estas herramientas informáticas, se pueden emplear como ayuda pedagógica antes o después de la asistencia …