Coast Of Southern Chile Research Articles

Unraveling Island Economies through Organic Residue Analysis: The Case of Mocha Island (Southern Chile)

Abstract Biophysical conditions played a fundamental role in early human colonization of insular territories, particularly in food-producing societies dealing with limited resources and the challenges of maintaining a sustainable carrying capacity. Studies on past human colonization of small oceanic islands thus offer insights into economic plasticity, ecological impacts, and adaptation of early food-producing groups. On the coast of southern Chile, early evidence is dated to 950 cal BP of island colonization by coastal populations with mainland subsistence systems based on the exploitation of marine resources, along with gathering, managing, and cultivating plants and hunting terrestrial animals. Strikingly, the extent to which these mixed economies contributed to insular colonization efforts is largely unknown. Here we used organic residue analysis of ceramic artifacts to shed light on the subsistence of populations on Mocha Island in southern Chile. We extracted and analyzed lipids from 51 pottery sherds associated with the El Vergel cultural complex that flourished in southern Chile between 950 and 400 cal BP. Chemical and stable isotope analysis of the extracts identified a range of food products, including C3 and C4 plants and marine organisms. The results reveal the central role of mixed subsistence systems in fueling the colonization of Mocha Island.

Emerging phycotoxins in the Chilean coast: First localized detection of the neurotoxic cyclic imine Pinnatoxin-G in shellfish banks

Pinnatoxins (PnTXs) produced by the cosmopolitan dinoflagellate Vulcanodinium rugosum are highly potent cyclic imines that represent a risk for seafood consumers, artisanal fisheries, and the local aquaculture industry. Among the eight known PnTXs, pinnatoxin-G (PnTX-G) is the most frequent toxin analog detected in shellfish. Despite PnTX-G is still not internationally regulated, the French Agency for Food, Environmental and Occupational Health and Safety established that a risk for human consumers may exist when the accumulation of PnTX-G in shellfish exceeds 23 μg kg−1. This study reports the first detection of these fast-acting lipophilic toxins in localized shellfish banks (Mytilus chilensis) from the Chilean coast. Among 32 sentinel sampling stations monthly monitored for phytotoxins detection and quantification between 2021 and 2022 along the southern Chilean coast (from 36°25′ S to 54°57′S), PnTx-G was only detected in shellfish from the southernmost region of Magallanes in concentrations that ranged between 15 and 100 μg kg−1, highlighting the binational (Chile/Argentina) Beagle Channel as a ‘hotspot’. As Chile is one of the major mussel producers worldwide, this result raises concern about the potential adverse effect of PnTXs for human health and point to the need of governmental actions for an enhanced monitoring of these emerging toxins. To date, the production of PnTXs has not yet been associated with any microalgae species in Chilean waters.

Comparative Analysis of the Genetic Diversity of Chilean Cultivated Potato Based on a Molecular Study of Authentic Herbarium Specimens and Present-Day Gene Bank Accessions.

At the end of the 1920s, Vavilov organized several potato-collecting missions in South and Central America. Vavilov and his colleagues, Juzepczuk and Bukasov, participated in these expeditions and worked on gathered material, designated two centers of potato varietal riches and diversity-the Peru-Bolivia high-mountain center and the southern coast of Chile. The WIR Herbarium holds authentic specimens of many taxa described by Russian taxonomists. Here, a set of 20 plastid DNA-specific markers was applied for 49 authentic herbarium specimens of Solanum tuberosum L. from the WIR Herbarium to analyze the genetic diversity of the landrace population collected by Juzepczuk in 1928 in southern-central Chile. Two plastid DNA types, T and A, and two chlorotypes were identified in herbarium specimens, with a clear predominance (96%) of chlorotype cpT_III. In addition, we analyzed 46 living Chilean accessions from the VIR field potato gene bank that were collected after the appearance of Phytophthora infestans in Chile. These living accessions were differentiated into four chlorotypes. Finding a D-type cytoplasm in living Chilean accessions that possess two new chlorotypes indicates a replacement of native cultivars and introgression from the wild Mexican species S. demissum that was actively used in breeding as a source of race-specific resistance to late blight.

Sixteenth-Century Bulge on the Coast of Chile

This paper traces the sixteenth-century addition and removal on maps of a bulge on the southern coast of Chile. Abraham Ortelius was primarily responsible for these changes and many cartographers followed his lead.Then, Ortelius rotated the coastline of Chile from northwest to north. Later, he dropped the latitude of the islands of San Pablo and Isla de los Tiburones down six degrees. He named the Amazon River “Río de las amazons.” Finally, he removed the cities with fake Native-American-sounding names along the Pacific coast of North America. The research underlying this paper examined over seven-hundred sixteenth-century maps made by sixdozen cartographers. This paper cites five-dozen maps by four-dozen cartographers. In the traceability section of this paper, this information was condensed into a traceability diagram, which shows the chronological flow of information among a score of cartographers. Using this information, this paper traced the influence of one cartographer on another: it showed who influenced whom. It showed the spread of knowledge. Ortelius was at the center of most of this knowledge explosion.

Circulation and distribution of suspended mesozooplankton carcasses in a mid-latitude estuary

The coast of southern Chile, located between 37° and 41°S, has many estuaries, which, together with their wetlands, still comprise a region with high biological richness and a high ecosystem value. The Valdivia River Estuary (VRE) stands out due to its relative size and commercial importance. This study analyses time series of environmental forcings and idealized model output to identify estuarine regimes and the subtidal circulation, and its influence on the distribution of Suspended Meso-Zooplankton Carcasses (SMZC), which may affect the local labile organic carbon input. Field campaigns were conducted in 2014 and 2015, and time series of metocean forcings span from 2012 to 2018. The characteristic regimes of the estuary that control the seasonal suspended particulate matter distribution were identified as Normal, Extreme, Exceptional Rainy, and Exceptional Dry. When mapped on the Geyer & MacCready circulation-stratification diagram, they coincide with partially-mixed, strongly-stratified, salt-wedge, and well-mixed water column structures, respectively. The idealized numerical model allows determining the subtidal circulation patterns induced by the along-channel density gradient, river discharge, and wind. The equilibrium SMZC distribution within the VRE during Normal and Exceptional Dry regimes was determined from the modeled circulation patterns. Model results indicated that, during the austral autumn (April 2014; Normal regime), the SMZC distribution shows a maximum concentration as low as 128 individuals per m3 located near the head of the estuary. This suggests low residence times of suspended carcasses within the estuary. During the austral summer (January 2015; Exceptional Dry regime), the SMZC distribution exhibits its maximum value near the mouth, exceeding 15,000 ind. m−3. These results suggest a massive carcass-derived carbon export towards the estuary mouth during dry seasons. Remarkably, the cross-section where maximum SMZC was predicted during this regime matches the area where large beds of Tagelus dombeii have been reported. Overall, this study highlights the importance of circulation-stratification relationships on the control of SMZC trapping mechanisms and on the identification of hotspots of benthic biomass in mid-latitude estuaries. Other estuaries with similar relationships and regimes might experience similar shifts in suspended meso-zooplankton distribution patterns in response to seasonal changes in forcings.

Inter‐sexual comparison of body biomass, proximate biochemical composition, and fatty acid profiles of new juvenile squat lobsters (Pleuroncodes monodon) in the Southeast Pacific Ocean

AbstractIn the wide distribution range of the red squat lobster Pleuroncodes monodon in the Southeast Pacific Ocean, there is an important nursery area on the southern coast of Chile. The new juvenile individuals from this nursery area are directly recruited into the adult squat lobster population, which is exploited by industrial fisheries. Despite the importance of new P. monodon juveniles for recruitment estimations in fishery management models, their bioenergetic condition and/or nutritional status at the onset of their benthic phase remain unknown, as are the differences in the biochemical composition and energy reserves of the two sexes, which could help explain the cost of the first breeding event in females. Therefore, in new juvenile squat lobsters with the same degree of immaturity, we quantified and compared between the sexes (female vs. male): the size (cephalothorax length, CL), body biomass (dry weight and organic matter), biochemical composition (proteins, glucose, and lipids), and fatty acid profiles (FAs). The results indicate that the CL of new juveniles was similar between the sexes, while the dry weight and organic matter presented significant differences, with higher values in new juvenile females (NJF) than new juvenile males (NJM). Similarly, the NJF had a higher content of proteins, glucose, and lipids than NJM. The FAs also showed significant differences between the sexes; the NJF had a higher content than NJM in all fatty acid classes (i.e., saturated, monounsaturated, and polyunsaturated), with the FAs DHA (C22:6n‐3), EPA (C20:5n‐3), oleic (C18:1n‐9), palmitic (C16:0), and eicosatrienoic (C20:3n‐3) significantly contributing to the differentiation of FA profiles between the sexes. All of the aforementioned differences among the multiple variables of the bioenergetic condition can indicate biochemical adaptations in the storage capacity of energy reserves, particularly among NJF that must support the high energy cost of the first reproductive event (characterized by embryo production and incubation), which occurs during the austral winter, a period predominated by cold‐water temperatures and scarce food availability in the habitat. Overall, our findings have significant implications in fishery management models. In this case, defining the bioenergetic condition of the new juvenile squat lobsters can aid in predicting the density and stability of the adult population, which is exploited by commercial fisheries.

Evacuation intention on the Southern Chilean coast: A psychological and spatial study approach

Evacuation from tsunami hazards is a complex problem that requires a transdisciplinary approach, i.e., several topics must be interrelated (including the perspective of the population) to better understand the evacuation process. One of these involves the psychological response of people to the configuration and location of evacuation sites. This paper contributes to exploring the evacuation phenomenon by using social and spatial sciences, in order to test how psychological and spatial indicators influence intention to evacuate to designated sites in Puerto Saavedra, Chile. The methodology involved the assessment of photographs representing different tsunami evacuation scenarios for Puerto Saavedra: the current scenario, with evacuation sites in built areas and in natural environments without emergency facilities; and the hypothetical scenario, in the same sites but with emergency facilities in the natural sites. Photographs were evaluated using three psychological indicators and a Likert scale in a questionnaire. A multiple regression analysis was then performed using ten spatial indicators to explore the most significant spatial variables that explain perception in each scenario. Finally, a multi-criteria evaluation technique was used to model optimal evacuation site locations by integrating data from the questionnaire and the multiple regression analysis. Results show that perceived safety, place attachment and restorativeness vary between scenarios. Natural evacuation sites with facilities from the hypothetical scenario, located at higher elevations and far from the coastline, evacuation routes and emergency infrastructure received higher evaluation values for the psychological indicators. The discussion delves into the challenge of using these outcomes for resilient planning in Puerto Saavedra, and for improving evacuation research with knowledge about perception and real evacuation behavior of different community groups, as well as through studies considering the amount, location and qualities of evacuation routes and sites. This will deepen our understanding of evacuation processes and models in different contexts.

Intertidal microhabitats as a shelter for assemblages of chitons at southern Chile

Environmental heterogeneity is one of the main hypotheses promoting changes in species diversity. Several abiotic and biotic factors that promote environmental heterogeneity generate physical and biological microhabitats, where organisms may find refuge from environmental stress. The abundance, species richness and body size structure of chiton assemblages were estimated in different intertidal microhabitats. These microhabitats (physical: crevices, pools, and boulders; biological: mussel beds, arborescent algae, and crustose algae) were sampled in six sites of the southern Chilean coast during the austral spring of 2016. The results of our study exhibited the species Chiton granosus as the most abundant, followed by C. magnificus and Tonicia chilensis. Species richness and abundance were higher in physical microhabitats, with boulders and crevices showing the highest values, respectively. The multivariate analyses revealed three groups with high similarities within them; the first group represented by crevices, pools, and mussel beds; the second group composed of arborescent and crustose algae; and the third group comprised by boulders. Mussel beds were considered “nursery grounds” for harbouring a high abundance of juveniles of C. granosus (<10 mm), whilst physical microhabitats and algae host the biggest specimens of both C. magnificus and T. chilensis (>30 mm). We suggest that in biological microhabitats, the patterns of species richness and abundance and body size structure would be determined by a relation of functional specificity derived from feeding habits; and, in physical microhabitats, these patterns would be explained by a relation of behavioural specificity derived from negative phototactism.

Two new species of Euplotes with cirrotype-9, Euplotes foissneri sp. nov. and Euplotes warreni sp. nov. (Ciliophora, Spirotrichea, Euplotida), from the coasts of Patagonia: implications from their distant, early and late branching in the Euplotes phylogenetic tree.

Two new Euplotes species have been isolated from cold shallow sandy sediments of the extreme Southern Chilean coasts: Euplotes foissneri sp. nov., from a low-salinity site at Puerto Natales on the Pacific coast, and Euplotes warreni sp. nov., from a marine site at Punta Arenas on the Atlantic coast. Euplotes foissneri has a medium body size (53×36 µm in vivo), a dorsal surface marked by six prominent ridges, a double dargyrome, six dorsal and two ventrolateral kineties, a buccal field extending to about 3/4 of the body length, an adoral zone composed of 28-32 membranelles, and nine fronto-ventral, five transverse and two or three caudal cirri. The bulky, hook-, horseshoe- or 3-shaped macronucleus is associated with one sub-spherical micronucleus. The central body region hosts taxonomically unidentified endosymbiotic eubacteria. Euplotes warreni has a small body size (39×27 µm in vivo), a smooth dorsal surface marked by three deep grooves, a double dargyrome, four dorsal and two ventrolateral kineties, a buccal field extending to about 2/3 of the body length, an adoral zone composed of 23-25 adoral membranelles, and nine fronto-ventral, five transverse and three caudal cirri. The macronucleus is hook- or C-shaped and associated with one spherical micronucleus. Endosymbiotic bacteria belonging to the genus Francisella reside preferentially in the anterior cell region. Both species lack the fronto-ventral cirrus numbered 'V/2', whereby their cirrotype-9 conforms to the so-called 'pattern I', which is the basic distinctive trait of the genus Euplotopsis Borror and Hill, 1995. Phylogenetic analyses of small subunit rRNA gene sequences, however, classify E. warreni into its own early branching clade and E. foissneri into a late branching clade. This indicates a polyphyletic nature and taxonomic inconsistency of the genus Euplotopsis, which was erected to include Euplotes species with cirrotype-9 pattern I.

Hibridaciones de saberes y lógicas culturales en la pesca

The goal of this paper is to reflect upon the processes of knowledge construction of Andalusian fishermen (Southern Spain), linked to diverse forms of material and cognitive appropriation systems of marine environment. Making use of a set of anthropological concepts embedded in the post-structuralist and ontological turns, I seek to explain the relational modes –both practical and cognitive, that link organically the poles of Nature and Culture, so that their limits are dissolved (Naturo-cultural relationships). The analysis is based on three main axes: community, relationality and the role of technological artifacts in these relational webs of knowledge. After this conceptualization, it is discussed whether we could consider this cultural model as an ontology, in particular its forms of environmental knowledge. Finally it is proposed to reorient the normative systems of fisheries management, promoting a dialogue: on one hand, between the traditional and scientific knowledge; on the other hand, between artisanal/traditional patterns and industrialized and market economies at the Southern coast of Chile. Thus, the focus is placed on the hybridization of practices and knowledge, as well as on the consequences of their combinations in the political and economic fields.

The Restorers of Chiloé by Rosabetty Muñoz

This series of poems deals with the restoration of religious statues distributed over the Catholic churches scattered over 21 islands of the remote archipelago of Chiloé, off the coast of southern Chile. A group of art restorers worked for years repairing the damages that had occurred over centuries of exposure to the elements, to the beautiful carved wooden images of Jesus, Mary and various Catholic saints. Since there were not enough priests to serve all the scattered population of Chiloé in Colonial times, the traveling priest appointed a fiscal to represent him in each major town, as a religious and legal authority. This position still exists to this day, although with less power than in Colonial times. The man who was serving as fiscal at the time of the restoration collaborated closely with the art specialists, as did various villagers. Even though none of the members of the restoration team was religious, these poems demonstrate the tenderness and respect they demonstrated, both in their dealings with the religious objects and with the devotees of these objects, the islanders. The saints of Chiloé were also beautifully photographed by Chilean photographer Mariana Mathews in 2008, as can be seen at the digital museum Castillo de Niebla: https://www.museodeniebla.gob.cl/sitio/Contenido/Galerias/36142:Santos-silentes-objetos-de-la-escuela-Santeria-de-Chiloe

Ocean circulation along the southern Chile transition region (38°–46°S): Mean, seasonal and interannual variability, with a focus on 2014–2016

Satellite and atmospheric model fields are used to describe the wind forcing, surface ocean circulation, temperature and chlorophyll-a pigment concentrations along the coast of southern Chile in the transition region between 38° and 46°S. Located inshore of the bifurcation of the eastward South Pacific Current into the equatorward Humboldt and the poleward Cape Horn Currents, the region also includes the Chiloé Inner Sea and the northern extent of the complex system of fjords, islands and canals that stretch south from near 42°S. The high resolution satellite data reveal that equatorward currents next to the coast extend as far south as 48°–51°S in spring-summer. They also display detailed distributions of forcing from wind stress and wind stress curl near the coast and within the Inner Sea. Between 38°–46°S, both winds and surface currents during 1993–2016 change directions seasonally from equatorward during summer upwelling to poleward during winter downwelling, with cooler SST and greater surface chlorophyll-a concentrations next to the coast during upwelling, opposite conditions during downwelling. Over interannual time scales during 1993–2016, there is a strong correlation between equatorial El Niño events and sea level and a moderate correlation with alongshore currents. Looking more closely at the 2014–2016 period, we find a marginal El Niño during 2014 and a strong El Niño during 2015 that connect the region to the tropics through the oceanic pathway, with some atmospheric connections through the phenomenon of atmospheric blocking (as noted by others). The period also includes a Harmful Algal Bloom of the dinoflagellate Alexandrium catenella during early-2016 that occurred during a sequence of physical conditions (winds, currents and temperatures) that would favor such a bloom. The most anomalous physical condition during this specific bloom is an extreme case of atmospheric blocking that creates a long period of calm in austral autumn after strong upwelling in austral summer. The blocking is related to the 2015–2016 El Niño and an unusual coincident positive phase of the Southern Annular Mode.

First assessment of persistent organic pollutant contamination in blubber of Chilean blue whales from Isla de Chiloé, southern Chile

Persistent organic pollutants (POPs) were assessed for the first time in blue whales from the South Pacific Ocean. Concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), hexachlorobenzene (HCB) and dichlorodiphenyltrichloroethane and its main metabolites (DDTs), were determined in 40 blubber samples from 36 free-ranging individuals and one stranded, dead animal along the coast of southern Chile between 2011 and 2013. PCBs were the most abundant pollutants (2.97–975 ng/g l.w.), followed by DDTs (3.50–537 ng/g l.w.), HCB (nd–77.5 ng/g l.w.) and PBDEs (nd–33.4 ng/g l.w). There was evidence of differences between sexes, with lower loads in females potentially due to pollutants passing to calves. POP concentrations were higher in specimens sampled in 2013; yet, between-year differences were only statistically significant for HCB and PBDEs. Lower chlorinated (penta > tetra > tri) and brominated (tetra > tri) congeners were the most prevalent among PCBs and PBDEs, respectively, mostly in agreement with findings previously reported in blue and other baleen whales. The present study provides evidence of lower levels of contamination by POPs in eastern South Pacific blue whales in comparison to those reported for the Northern Hemisphere.

Changes in latitudinal sea surface temperature gradients along the Southern Chilean margin since the last glacial

The comparison between different climate model simulations of water hosing experiments under glacial conditions points toward diverging responses in Sea Surface Temperature changes (SST) especially in the Southeast Pacific (SEP). This suggests that reconstituting the latitudinal SST gradient in the SEP is a critical parameter for a better understanding of the mechanisms behind the abrupt climatic events since the last glacial period. Here we present, high-resolution records of SST, using planktonic foraminiferal assemblages and alkenone temperature reconstructions and stable oxygen and carbon isotopes from three deep-sea sediment cores along a latitudinal transect off the southern Chilean coast. This allowed us to reconstruct the variations of the latitudinal SST gradient and the Subtropical Front movements in the SEP. The SST results suggest a clear Antarctic timing consistent with the bipolar seesaw control, especially during the late glacial and the deglaciation. Our records do not suggest a complete oceanic heat transfer signal, highlighting the implication of an atmospheric component in the heat transfers between the two hemispheres, controlled by the latitudinal movements of the intertropical convergence zone in the Atlantic and the associated weaker South Pacific westerly split jet. Furthermore, our records indicate variable conditions during the Holocene, and also emphasize the influence of local fresh water inputs from the Patagonian ice sheet and/or precipitation on the SST fresh water input estimates along the Chilean margin (North and South of 49° S) from the onset of the deglaciation until 8 kyr cal. BP.

Spatial overlap of shark nursery areas and the salmon farming industry influences the trophic ecology of Squalus acanthias on the southern coast of Chile.

Potential interactions between marine predators and humans arise in the southern coast of Chile where predator feeding and reproduction sites overlap with fisheries and aquaculture. Here, we assess the potential effects of intensive salmon aquaculture on food habits, growth, and reproduction of a common predator, the spiny dogfish—identified as Squalus acanthias via genetic barcoding. A total of 102 (89 females and 13 males) individuals were collected during winter and summer of 2013–2014 from the Chiloé Sea where salmon aquaculture activities are concentrated. The low frequency of males in our study suggests spatial segregation of sex, while immature and mature females spatially overlapped in both seasons. Female spiny dogfish showed a functional specialist behavior as indicated by the small number of prey items and the relative high importance of the austral hake and salmon pellets in the diet. Immature sharks fed more on pellets and anchovies than the larger hake‐preferring mature females. Our results also indicate that spiny dogfish switch prey (anchovy to hake) to take advantage of seasonal changes in prey availability. Despite differences in the trophic patterns of S. acanthias due to the spatial association with intensive salmon farming, in this region, there appears to be no difference in fecundity or size at maturity compared to other populations. Although no demographic effects were detected, we suggest that a range of additional factors should be considered before concluding that intensive aquaculture does not have any impact on these marine predators.

Novel microsatellite markers for Pyura chilensis reveal fine-scale genetic structure along the southern coast of Chile

Studying the geographic scale of gene flow and population structure in marine populations can be a powerful tool with which to infer patterns of larval dispersal averaged across generations. Here, we describe the development of ten novel polymorphic microsatellite markers for an important endemic ascidian, Pyura chilensis, of the southeastern Pacific, and we report the results from fine-scale genetic structure analysis of 151 P. chilensis individuals sampled from five sites constituting ∼80 km of coastline in southern Chile. All microsatellite markers were highly polymorphic (number of alleles ranged from 12 to 36). Our results revealed significant deviations from Hardy–Weinberg equilibrium (HWE) for most loci, suggesting the presence of either null alleles or deviations from random mating within sampled sites. However, we found a significantly higher spatial autocorrelation and higher mean pairwise relatedness among individuals sampled from the same sites than would be expected if samples were randomly distributed across all sites; this suggests that spatial configuration and reproduction might not be random within sites. Our results indicate the presence of a weak but significant genetic structure between sites (overall F ST = 0.015, p < 0.001). Despite the short pelagic larval duration of this species, geographic distance does not appear to correlate with genetic distances between sites. From the results gathered here, it seems possible that genetic structure at this spatial scale is driven to some extent by local population dynamics (deviations from random mating and/or a large proportion of larvae settling in proximity of relatives), yet infrequent long-distance dispersal events might also be responsible for the relatively weak spatial heterogeneity between sites. Overall, our results both highlight the utility of this new marker set for population genetic studies of this species and provide new evidence regarding the complexity of the small-scale population structure of this species.

Otolith shape analysis as a tool for stock identification of the southern blue whiting, Micromesistius australis

The southern blue whiting, Micromesistius australis (Norman, 1937), is an important demersal resource associated with the slope and continental shelf of southern Chile, Argentina and the Malvinas/Falkland Islands. Recent studies have reported schools of adult fish from Atlantic waters migrating along the southern Chilean coast in mid-winter, moving northwards to spawn in August (47º-51ºS), and then returning to Atlantic waters, presumably to feed. The migratory pattern suggests the presence of one or more stock units associated with the South American coast. In the present study, “otolith morphometry” is used to determine the stock structure of M. australis based on applications of basic size descriptors (SDs) (area, perimeter and otolith size), shape indices (SIs) (circularity, squareness, shape factor, roundness, ellipticity), and normalised elliptical Fourier descriptors (NEFDs). Samples were collected during the winter and spring of 2010, during the reproductive period, in the economic zone of southern Chile (36º-57ºS), in the Pacific Ocean and around the Falkland Islands economic zone (50º-52ºS) in the Atlantic Ocean. Analyses were conducted to include the effects of size, sex and age. A stepwise canonical discriminant analysis showed that fish were successfully discriminated with SDs, SIs and NEFDs. In this analysis, 86.4% and 70.1% of the fish were correctly classified as belonging to the Atlantic and Pacific stocks, respectively. A multivariate analysis of variance showed that the mean values of the NEFDs, SDs, and SIs did not vary significantly between sexes within areas (P &gt; 0.05), but varied significantly between the Pacific and Atlantic oceans (P &lt; 0.05). These results highlighted that otolith shape analysis can be a useful tool to evaluate the potential level of mixing in feeding areas where both stocks, the Pacific and Atlantic units, are expected to co-occur.

A new species of Hemipera Nicoll, 1913 (Digenea: Derogenidae) from fishes of the intertidal rocky zone of Chile.

A new species, Hemipera cribbi sp. nov., is described. This trematode was found in three intertidal fish species: Scartichthys viridis (Valenciennes) (Blenniidae), Gobiesox marmoratus Jenyns (Gobiesocidae) and Myxodes viridis Valenciennes (Clinidae) from the central and southern coast of Chile. Of 233 individuals of S. viridis from the central coast examined, 19 were infected. From the southern coast, nine individuals of S. viridis (one infected), five individuals of G. marmoratus (four infected), and 16 individuals of M. viridis (one fish infected) were examined. Hemipera cribbi sp. nov. is distinguished from the five other congeneric species mainly in the body size, being the smallest and narrowest species in the genus, reaching five times longer than wide. This is the first species of the genus described for the South Pacific Ocean off South America. ITS2 rDNA sequences of Hemipera cribbi sp. nov. from each host and locality were identified.

DESMODORIDAE (NEMATODA) MIT EXTREM LANGEN SPICULA AUS SUDAMÉRICA

1. It is discussed that in five from the six orders of freeliving marine nematodes there are species with extraordinary long spicula. These species live in mud, sand and between algae. Extraordinary long spicula are slender, have with very few exceptions the form of an elongated comma and are accompanied by a 1) Die Arbeit wurde gefordert durch Exkursionsbeihilfen von „ORPLANLos Canales" (Chile) zur Küste Patagoniens und durch eine Reisebeihilfe der Deutschen Forschungsgemeinschaft (Bundesrepublik Deutschland) nach Kolumbien. In Kolumbien konnte ich am Instituto Colombo-Alemán in Santa Marta arbeiten. Allen drei Institutionen sei herzlich gedankt. slender gubernaculum without apophysis. In the respectives females the sexual organs are built normally as in other species in which the males possess normal spicula (1 exception). 2. 4 species belonging to the family Desmodoridae are described: Microlaimus acicularis n. sp., Molgolaimus tenuispiculum Ditlevsen 1921 (both to Microlaiminae), Desmodora (Desmodora) filispiculum n. sp. and D.(D.) sinuata n. sp. (both to Desmodorinae). The three first mentioned species are collected from the Pacific coast of Southern Chile, the last mentioned one from the Atlantic coast of Colombia.3. The spicula of Molgolaimus tenuispiculum and Desmodora sinuata are not only very elongated but furthermore of a very outstanding form.4. Within the genus Desmodora de Man 1889 the subgenus Desmodorella Cobb 1933 is supposed to be synonym to the subgenus Desmodora. 5. Similarities which exist between Desmodora, the epsilonematids and draconematids are discussed.

How manySiphonariaspecies (Gastropoda: Euthyneura) live in southern South America?

Fil: Guller, Marina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales Bernardino Rivadavia; Argentina