Data on monogenean (Platyhelminth) parasites in 11 populations of Astyanax aeneus (Pisces: Teleostei) in a neotropical river in Chiapas, south Mexico.

The data presented in this article are related to the research article entitled "Aggregation and negative interactions in low-diversity and unsaturated monogenean (Platyhelminthes) communities in Astyanax aeneus (Teleostei) populations in a neotropical river of Mexico" publicated in Int. J. Parasitol. Parasites Wildl. 8 (2019) 203-215. https://doi.org/10.1016/j.ijppaw.2019.02.005. This article describes the communities of monogenean parasites in 11 populations of a small characid freshwater fish Astyanax aeneus (Günther) separated by small geographical distances along 60 km of the Lacantún river in Chiapas, Mexico. We examined 15 A. aeneus from each of 11 locations (one sample in February, a second sample in August 2012), situated at the mouth of the streams opening into the main body of the Lacantún river, at the Montes Azules Biosphere Reserve in the Lacandon forest, Chiapas in southern Mexico. The area of study is located ∼800 km from the mouth of the Usumacinta river in the Gulf of Mexico. In this paper we provide the data for 12 monogenean taxa. The material in this Data in Brief paper comprised the raw data on the abundance distribution of each monogenean taxa recorded in each of the locations; i. e. the number of helminth individuals of each of 12 taxa found in each one individual of A. aeneus from each of 11 localities. The data set is contained in a single table text document including one matrix per date of collection and locality of monogenean species (lines) per host A. aeneus (columns).

Aggregation and negative interactions in low-diversity and unsaturated monogenean (Platyhelminthes) communities in Astyanax aeneus (Teleostei) populations in a neotropical river of Mexico.

We studied monogenean communities of 11 populations of Astyanax aeneus (Günther) separated by small geographical distances along 60 km of the Lacantún river in Chiapas, Mexico, in February and August 2012. We found 12 monogenean taxa. Amongst these, five species specialist for Astyanax were widely distributed regionally, constituting 90% of the total collected monogeneans, with one of these species dominating most component communities. The high similarities in terms of composition between the component communities (SJaccard > 60%) as well as in terms of the abundance and composition between infracommunities (SBray Curtis > 40%), provide empirical evidence that transmission, both between hosts at the same location and between component communities, is high and effective. No resemblance pattern was detected between locations in terms of their spatial distribution. The composition of these communities was spatially and temporally consistent over the two very different weather periods sampled. These communities were not saturated. Our analysis suggests that the potential richness of the infracommunities is proportional to the number of monogenean species available in the component community. We found aggregation in the populations and between monogenean species. Intraspecific aggregation is density dependent, suggesting that intraspecific competition for space is not a limiting factor for the development of the population. We evaluated the associations for each species pair and detected 77% negative interactions (134/177 associations), suggesting that interspecific competition plays an important role in shaping these communities. The negative correlations of abundance between pairs of species contributes to confirmation of competition. Intraspecific aggregation increased relative to interspecific aggregation with richness in the component community, facilitating coexistence of the species. Our results suggest that these are interactive communities, where monogeneans disperse efficiently from a common source, colonize patches (hosts) together, and compete with other species even at low population densities. Finally, the coexistence of these species is favored by the unpredictable recruitment and aggregated use of fragmented resources.

Diaphorocleidus machacae n. sp. (Monogenea) Infecting the Gill Lamellae of Brycon guatemalensis (Characiformes: Bryconidae) from the Rio Lacantún Basin in Chiapas, Mexico.

BACKGROUND: There are currently nine known gill monogenean species of Diaphorocleidus Jogunoori et al. (Systematic Parasitology 58:115-124, 2004) (Dactylogyridae) which are dispersed within and/or among five fish families in the Neotropical Characiformes: Bryconidae, Acestrorhynchidae, Characidae, Iguanodectidae, and Hemiodontidae. During a fish parasitological study carried out in the Rio Lacantún from Chiapas, Mexico, a new species of Diaphorocleidus on the gill lamellae of Brycon guatemalensis Regan, 1908, was discovered. OBJECTIVE: Our objective was to morphologically describe the new parasite species by comparing it with previously described species of Diaphorocleidus and other known dactylogyrids on Characiformes. METHODS: Worms were fixed with 4-5% formalin solution, observed and measured as temporary or permanent mounts stained with Gomori's trichrome, and mounted in Canada balsam. In addition, some specimens were mounted on slides using a mixture of lactic acid (LA) and glycerin-ammonium picrate (GAP) and then remounted in Canada balsam to obtain measurements of the haptoral structures and copulatory complex. Drawings were made with the aid of a drawing tube using a Leica microscope DM2500 with Nomarski interference contrast. RESULTS: The new species differs from previously described congeneric species in having comparatively biggest body size [i.e., 800-1200 µm vs. 222-340 µm in Diaphorocleidus armillatus Jogunoori et al. (Systematic Parasitology 58:115-124, 2004) (type species of the genus)]; two prostatic reservoirs; rod-shaped accessory piece; a sucker-like structure associated with the genital pore; vaginal duct looping left intestinal cecum and opening on the dextro-dorsal margin of body; anchors with conspicuous basal folds on the deep roots weakly developed. CONCLUSIONS: Consistently with the previous phylogenetic hypotheses about the origin of bryconids (20 mya late Oligocene-early Miocene) in Central America, that morphological differentiation in D. machacae n. sp. in Mexico may somewhat reflect the insights of an early dispersal of a common ancestor of Diaphorocleidus to the area in comparison with that of a late invasion of their congeners [i.e., according to the origin of B. petrosus (10 mya) 10 mya] in Central America. The present finding brings to ten, the number of known species of Diaphorocleidus, and represents the second described species of this genus occurring in a freshwater native host in Mexico.

New species of Paracolpenteron n. gen. and Ancyrocephalus (Monogenea, Dactylogyridae) inhabiting the urinary bladder and gills of the Maya needlefish Strongylura hubbsi (Beloniformes, Belonidae) from Chiapas, Mexico.

Parasitological examination of the maya needlefish Strongylura hubbsi Collette (Belonidae) from the Rio Lacantún basin in the Montes Azules Biosphere Reserve, Chiapas, Mexico showed that specimens were parasitized by two monogenean species in two different sites: Paracolpenteron hubbsii n. gen., n. sp in the urinary bladder and Ancyrocephalus chiapanensis n. sp in the gill lamellae. Paracolpenteron hubbsii differs from other dactylogyrid species without a haptoral anchor/bar complex infecting the urinary systems, gills and nasal cavities by the general morphology of hooks, a dextral vaginal opening, a tubular male copulatory organ comprising a base from which a coiled shaft arises in counterclockwise direction, and an unarticulated Y-shaped accessory piece. Ancyrocephalus chiapanensis n. sp. resembles Ancyrocephalus cornutus William & Rogers, 1972 from the gills of Strongylura marina from Florida from which it differs in possessing a twisted tube of the male copulatory organ (curved in A. cornutus), ventral bar with cavities on the ends (cavities absent in A. cornutus) and by the size of the ventral (length 31-34 µm vs. 24-27 µm in A. cornutus) and dorsal (length 25-28 µm vs. 18-22 µm in A. cornutus) anchors. These new monogeneans are described herein and their biogeography is briefly discussed based on the previous phylogenetic hypotheses concerning the host family.

Percepciones, conocimiento local y expectativas de campesinos cafetaleros en puriscal, Costa Rica / Perceptions, lcaal knowledge and expectations of peasant coffe farmers in purriscal, Costa Rica

El propósito de este estudio fue sistematizar las percepciones y saberes locales emitidos por una comunidad campesina de Costa Rica, principalmente en cuanto a su visión del estado actual y las expectativas para el futuro de la actividad cafetera. Se realizaron entrevistas en profundidad para indagar la percepción sobre el estado actual de la caficultura y las expectativas para el futuro. Las entrevistas se desarrollaron en 39 fincas cafetaleras del cantón de Puriscal, Costa Rica. El estudio tomó elementos de los procedimientos y técnicas de enfoques cualitativos como grounded theory y sistematización de experiencias. Los temas abordados fueron enfocados hacia tres tópicos: estado actual y futuro de la actividad cafetera; opiniones sobre la caficultura orgánica, y expectativas y necesidades de capacitación. A pesar de que el mayor número de enunciados sugiere una actitud pesimista frente a la crisis de esta actividad, casi la mitad de ellos denotan una actitud optimista frente a esta actividad. El mayor número de enunciados sistematizados evidencia una actitud optimista frente a la producción orgánica. La mayor parte de expectativas denotan la necesidad de capacitarse en manejo de abonos orgánicos y control de enfermedades.

This study aims to systematization ofcapture the experience of both perceptions and local knowledge of a Peasant community from Costa Rica, mainly, about his on their vision and expectation on the coffee growingth activity. Interview iIn- depth interviews were done carried out to inquiry perceptions on current state of coffee production systems and expectations at regarding future of coffee productiongrowers. Interviews were applieds in 39 coffee farms of Cantón of Puriscal, Costa Rica. This study used methods and techniques from qualitative approaches such as like the grounded theory and the systematization of experiences. The issues treated were related with to three topics: present and future state of coffee production systems; opinions on organic coffee production systems, and training expectations and requirements of training. Even though the most statements suggested a pessimistic attitude in frontregarding the crisis of coffee productionactivity, almostready half of producers noted an optimistic attitude towardsin front of the future. The mMost of the systemized statements evidenced an optimistic attitude regardingin front organic coffee production system. The mostmajority of expectations systematized indicate the need requirements of training in about both management of organic fertilizers management and disease control of diseases.