Anatomy of growth rings at the Yucatán Peninsula

The dendrochronological characteristics of 52 tree species from the semi-tropical forests of the Yucatán Peninsula were opportunistically explored in a salvage dendrochronological study. The existence of clear growth rings in these trees is a key prerequisite for further studies and a convincing demonstration of the dendrochronological potential of tropical tree species will allow the development of future research programs concerning the ecology of the species and inferences about past environmental changes detected from tree rings. Many aspects of the conservation and management of Yucatec forests should be urgently addressed to aid in the development of improved strategies beyond the scope of more traditional agricultural uses. Development of tree-ring analyses from selected local species can be of substantial assistance in these initiatives.     

Seasonal and annual variability in the phytoplankton community of the Raunefjord,west coast of Norway from 2001–2006

Changes in phytoplankton community composition potentially affect the entire marine food web. Because of seasonal cycles and inter-annual variations in species composition, long-term monitoring, covering many sequential years, is required to establish a baseline study and to reveal long-term trends. The current study describes the phytoplankton biomass variations and species composition in relation to hydrographic and meteorological conditions in the Raunefjord, western Norway, over a 6-year period from 2001 to 2006. The extent of inflow or upwelling in the fjord varied from year to year and resulted in pronounced differences in water column stability. The annual phytoplankton community succession showed some repeated seasonal patterns, but also high variability between years. Two to four diatom blooms were observed per year, and the spring blooms occurring before water column stratification in March were dominated by Skeletonema marinoi and Chaetoceros socialis, and other Chaetoceros and Thalassiosira spp. Blooms of the haptophytes Phaeocystis pouchetii and Emiliania huxleyi were irregular and in some years totally absent. Although E. huxleyi was present all year round it appeared in bloom concentrations only in 2003, when the summer was warm and the water column characterized by high surface temperatures and pronounced stratification. The annual average abundance of both diatoms and flagellates increased during the six years. Despite the high variation from year to year, our investigation provides valuable knowledge about annual phytoplankton community patterns in the region, and can be used as a reference to detect possible future changes.     

Distribution of Ecteinascidia turbinata (Ascidiacea: Perophoridae) in mangroves of the Yucatán Peninsula, Mexico

The ascidian Ecteinascidia turbinata synthesizes some of the most promising substances against solid-type tumors, but the only available source are the natural populations of this tunicate, which is reared or collected in different parts of the world. A total of 33 locations were sampled in the Gulf of Mexico and the Yucatan Peninsula. The tunicate was not found in Veracruz, Tabasco and Campeche, but it was well established on mangrove roots in the Yucatan Peninsula where we estimated densities more or less equal to one colony and an average production of 115 g of biomass per lineal meter of mangrove coastline in one location (Río Lagartos). Sustainable management appears to be possible.     

Aquatic ecosystems of the Yucatán Peninsula (Mexico), Belize, and Guatemala

This study presents limnological and morphological characteristics, physical and chemical properties of waters, and geochemistry of surface sediments for 63 aquatic ecosystems located on the karst Yucatán Peninsula and surrounding areas of Belize and the Guatemalan highlands and eastern lowlands. Our principal goal was to classify the aquatic systems based on their water variables. A principal component analysis (PCA) of the surface water chemistry data showed that a large fraction of the variance (29%) in water chemistry is explained by conductivity and major ion concentrations. The broad conductivity range, from 168 to 55,300 μS cm⁻¹ reflects saline water intrusion affecting coastal aquatic environments, and the steep NW–S precipitation gradient, from ~450 to >3,200 mm year⁻¹. Coastal waterbodies Celestún and Laguna Rosada displayed the highest conductivities. Minimum surface water temperatures of 21.6°C were measured in highland lakes, and warmest temperatures, up to 31.7°C, were recorded in the lowland waterbodies. Most lakes showed thermal stratification during the sampling period, with the exception of some shallow (<10 m) systems. Lakes Chichancanab, Milagros, and Bacalar displayed sulfate-rich waters. Waters of sinkholes had relatively high conductivities (<3,670 μS cm⁻¹) and a broad range of δ¹⁸O values (−4.1 to +3.8‰). Ca, HCO₃, and SO₄ dominated the waters of the lowland lakes, whereas Na was the dominant cation in highland lakes. Coastal aquatic ecosystems were dominated by Na and Cl. Cluster analysis based on surface water variables classified aquatic environments of the lowlands and highlands into three groups: (1) lowland lakes, ponds, wetlands, and coastal waterbodies (2) highland lakes, and (3) sinkholes and rivers. A broad trophic state gradient was recorded, ranging from the eutrophic Lake Amatitlán and the Timul sinkhole to oligotrophic Laguna Ayarza, with the highest water transparency (11.4 m). We used major and trace elements in surface sediments to assess pollution of waterbodies. Lakes Amatitlán, Atescatempa, El Rosario, Cayucón, Chacan-Lara, La Misteriosa, rivers Subín and Río Dulce, the wetland Jamolún, and the sinkhole Petén de Monos showed evidence of pollution and urban development. Their surface sediments displayed high concentrations of As, Cu, Fe, Ni, Pb, Se, Zn, and Zr, which suggest moderate to strong pollution.     

Genetic studies of human apolipoproteins. XIII. Quantitative polymorphism of apolipoprotein C-III in the Mayans of the Yucatán Peninsula

Apolipoprotein C-III (APO C-III) is a structural component of very-low-density and high-density lipoprotein particles and is an inhibitor of lipoprotein lipase. In a study of genetic variation of apolipoproteins in the Mayan population of the Yucatán peninsula, we observed a quantitative polymorphism in APO C-III levels. This polymorphism is expressed as variation in immunoblot staining intensity following isoelectric focusing and as variation in plasma levels of APO C-III determined by radial immunodiffusion. This variation is consistent with the presence in Mayans of an allele associated with low levels of plasma APO C-III which we have designated APO C-III*D. Analysis of the distribution of APO C-III levels yields a gene frequency estimate for the deficiency allele of 0.59. There is a significant positive correlation between total plasma APO C-III levels and total plasma cholesterol and triglyceride levels, the lowest levels of cholesterol and triglycerides being seen in individuals homozygous for the deficiency allele. This observation is consistent with the proposed role of APO C-III in lipoprotein metabolism. Family data to determine whether this deficiency allele is due to mutation at the APO C-III structural locus were not available. However, molecular analysis using cloned probes from the APO A-I/C-III/A-IV gene cluster revealed no gross DNA rearrangement or deletion of sequences in this region in homozygous deficient individuals.     

Agars from three species of Gracilaria (Rhodophyta) from Yucatán Peninsula

Gracilaria cervicornis, Gracilaria blodgettii and Gracilaria crassissima growing along the coasts of Yucatán were investigated for their agar content. The effect of different concentrations of NaOH in the alkali treatment was evaluated. The three species of Gracilaria produced agars, both native and alkali treated, with different properties confirming the heterogeneity of the agar polymers in this genera. G. cervicornis produces agar polymers with an occurrence of methoxylation and sulphation at the C-6 of the beta-D-galactose residues, and with an extra methylation due to the presence of the 4-O-methyl-alpha-L-galactose residue. The presences of these residues is responsible for the extremely poor gelling ability of its agarocolloids, whose commercial value seems to be quite low. Agar extracts from G. blodgettii showed the typical pattern of unsubstituted agar with a very low degree of methylation on both galactose residues. The discrepancy found between sulphate content and NMR data of agar from this species requires a more detailed structural investigation. G. crassissima produces a good quality agar after sulphate precursor sequences have been removed by alkaline treatment, and it may be considered for exploitation as a source of commercial grade agar. Alkali treatment was effective both in removing alkali-labile sulphate and increasing the gel strength in G. crassissima but not in G. cervicornis and G. blodgettii.     

Sayil Revisited: Inferring Terminal Classic Population Size and Dynamics in the West-Central Yucatán Peninsula

Research at the site of Sayil in the Yucatan Peninsula has provided a valuable database for making inferences about the Terminal Classic (A.D. 750–1000) occupation of the Puuc region. This article evaluates and modifies previous demographic estimates for the site and considers the long-term implications associated with supporting this many people. Although a relatively high level of population was possible because of the excellent soils in the region, their natural fertility could not have been sustained indefinitely. The apparent demographic load on the proposed Sayil system would have required an intensive cropping strategy that may not have been sustainable for more than 75 years. This conclusion not only indicates how long the principal occupation of Sayil may have lasted, but more importantly, how the occupational dynamics during the Terminal Classic may have played out in the greater Puuc region.     

Seasonal dynamics of chemotypes in a freshwater phytoplankton community – A metabolomic approach

Cyanobacteria are known to produce a huge variety of secondary metabolites. Many of these metabolites are toxic to zooplankton, fish, birds and mammals. Therefore, the toxicity of cyanobacterial blooms is strongly dependent on the cyanobacterial strain composition. These strains produce distinct bouquets of secondary metabolites, and thus constitute different chemotypes. Some of the cyanobacterial metabolites are potent inhibitors of gut proteases of the filter-feeder Daphnia. Here, we investigate the seasonal dynamics of secondary metabolites in a phytoplankton community from a hypertrophic pond, making use of a new metabolomic approach. Using liquid chromatography coupled with high-resolution mass spectrometry (LCMS), we obtained mass spectra of phytoplankton samples taken on different dates throughout the summer season. By applying multivariate statistics, we combined these data with the protease inhibition capacity of the same samples. This led to the identification of metabolites with cyanobacterial origin and as well of distinct cyanobacterial chemotypes being dominant on different dates. The protease inhibition capacity varied strongly with season, and only one out of 73 known cyanobacterial protease inhibitors could be confirmed in the natural samples. Instead, several so far unknown, putative protease inhibitors were detected. In conclusion, the creation of time series of mass spectral data of a natural phytoplankton community proved to be useful for elucidating seasonal chemotype succession in a cyanobacterial community. Additionally, correlating mass spectral data with a biological assay provides a promising tool for facilitating the search for new harmful metabolites prior to structure elucidation.     

Polliniferous plants and foraging strategies of Apis mellifera (Hymenoptera: Apidae) in the Yucatán Peninsula,Mexico

A study of the most important polliniferous plants for European and Africanized honeybees (Apis mellifera L.) was made in Quintana Roo state. Comparisons were made between the plants visited by both bee types in order to determine whether there were qualitative or quantitative differences in their choice of plant species. Also some foraging strategies of the honeybees were analysed. Pollen from pollen load samples was acetolysed and mounted on slides. Subsequently the pollen grains were identified, counted and photographed. A total of 206 pollen load samples were collected at Palmas and St. Teresa during two years. The most frequent species in the pollen load samples from European and Africanized honeybees were Cecropia peltata, Metopium brownei, Lonchocarpus sp. 2, Viguiera dentata, Eragrostis sp. 1, Bursera simaruba and Eupatorium albicaule. Both types of honey bees show a high reliance on pollen from only a few species, the first five named above comprised around 50% of all the mean percentage frequencies. Families that contributed with the largest number of pollen species were Fabaceae, Asteraceae, Boraginaceae, Convolvulaceae, Euphorbiaceae, Sapindaceae, Poaceae, Myrtaceae, Sapotaceae and Tiliaceae. C. peltata, Trema micrantha, B. simaruba, Eugenia sp. 1, Thouinia canesceras, Pouteria sp. 1, Mimosa bahamensis and V. dentata, were the pollen species with the largest percentages of occurrence in both European and Africanized bee pollen load samples, and also represent a "long-term" food resources during the year.     

Primates Living Outside Protected Habitats Are More Stressed: The Case of Black Howler Monkeys in the Yucatán Peninsula

The non-invasive monitoring of glucocorticoid hormones allows for the assessment of the physiological effects of anthropogenic disturbances on wildlife. Variation in glucocorticoid levels of the same species between protected and unprotect areas seldom has been measured, and the available evidence suggests that this relationship may depend on species-specific habitat requirements and biology. In the present study we focused on black howler monkeys (Alouatta pigra), a canopy-dwelling primate species, as a case study to evaluate the physiological consequences of living in unprotected areas, and relate them with intragroup competition and competition with extragroup individuals. From February 2006 to September 2007 we collected 371 fecal samples from 21 adults belonging to five groups (two from protected and three from unprotected areas) in Campeche, Mexico. We recorded agonistic interactions within groups and encounters with other groups (1,200 h of behavioral observations), and determined fecal glucocorticoid metabolite (FGM) concentrations with radioimmunoassays. We used linear mixed models and Akaike''s information criterion to choose the best model explaining variation in FGM concentrations between protected and unprotected areas calculated from five categorical variables: habitat type (protected vs. unprotected), participation in agonistic interactions, intergroup encounters, sex and female reproductive state, and season. The best model included habitat type, the interaction between habitat type and agonism, and the interaction between habitat type and season. FGM concentrations were higher in unprotected habitats, particularly when individuals were involved in agonistic interactions; seasonal variation in FGM concentrations was only detected in protected habitats. High FGM concentrations in black howler monkeys living in unprotected habitats are associated with increased within-group food competition and probably associated with exposure to anthropogenic stressors and overall food scarcity. Because persistent high GC levels can be detrimental to health and fitness, populations living in disturbed unprotected areas may not be viable in the long-term.     

Distribution of some calanoida (Crustacea: Copepoda) from the Yucatán Peninsula, Belize and Guatemala

Southern Mexico and Central America have many water bodies of different morphology and water chemistry with an interesting zooplankton fauna, originating from North or South America. A set of 63 samples, taken in 2005 and 2008, from water bodies of the Yucatan Peninsula karst, Belize and Guatemala, were studied for the content of calanoid copepods. Old and recent literature was used to determine animals to species level. Drawings were prepared with a microscope and a camera lucida. A total of 32 samples with totally six species contained calanoid copepods: one estuarine pseudodiaptomid and five freshwater diaptomids. Pseudodiaptomus marshi was found at different salinities. It is confirmed that the commonest diaptomids in the Yucatan Peninsula are Arctodiaptomus dorsalis and Mastigodiaptomus nesus. The former was also recorded from Lake Amatitlan. Mastigodiaptomus nesus is as widespread as A. dorsalis but it is absent from the Lake Peten area in Guatemala. Mastigodiaptomus reidae was found in two shallow habitats, these specimens differ from those from the type locality by having a set of peculiar large spine-like processes on the last thoracic and the urosome segments of the females. Leptodiaptomus siciloides was found only in Lake Ayarza with high salinity. Prionodiaptomus colombiensis occurred in the highlands of Guatemala in Lago de Güija and in the Peten area in Laguna Sacpuy. We contributed with our occurrence records to a better knowledge of the geographic distribution of some calanoid copepods. Morphological findings in some species are of value for taxonomic differentiation between species.     

Geospatial analysis of pollen records from the Yucatán peninsula, Mexico

Changes in distribution of semi-evergreen forest in the Yucatán peninsula and variation of precipitation during the late Holocene were inferred using a geographical information system. Deterministic methods for spatial interpolation using fossil pollen data from seven cores elucidated environmental changes. The changes in the distribution of the semi-evergreen forest allowed to us infer variations in precipitation in the area and to distinguish whether changes of forest cover are a consequence of climate and/or of human activities. The reconstruction of the Preclassic period (at 550 and 50 b.c.) indicates higher precipitation than at present and suggests a more closed vegetation cover. Around a.d. 450 the vegetation acquired an open character indicating a reduction in precipitation. During this time the decrease in forest was not homogeneous in the Yucatán peninsula, indicating human impacts in certain areas. A reduction in forest cover but not a complete deforestation of the region is assessed during the Classic period (a.d. 450). The reconstruction of a.d. 950 shows the recovery of the forest and is related to the Medieval warm period. Geographical information systems are useful tools to reconstruct the spatial history of the vegetation of the Yucatán peninsula during the late Holocene.     

Progressive changes in the structure and dynamics of the phytoplankton community along a pollution gradient in a lowland river — a multivariate approach

The phytoplankton of the River Lujan (Buenos Aires, Argentina) was studied for a period of 18 months, together with physical and chemical variables, in relation to a pollution gradient. 167 taxa were recorded within a seasonal succession characterized by dominance of diatoms with a brief summer green algae facies. A combination of several biotic indices and multivariate analysis was employed to assess the impact of pollution on the phytoplankton community. The biotic indices used were species diversity and richness, algal quotients (green algae/diatom ratio, Centrales/Pennales ratio) and the SD succession rate index. Multivariate procedures included cluster analysis and ordination by PCA of both species and samples, stepwise discriminant analysis and multiple discriminant analysis of variance (MANOVA). Results indicate that community dynamism is attenuated at the more polluted sites, concomitant with an increased predominance of a broad-tolerance algal assemblage, co-dominated by Cyclotella meneghiniana and Nitzschia stagnorum. The changes in the community structure and dynamics described herein involved alterations in the distribution and relative proportions of the algae, rather than modifications in the basic species composition. These changes may not be readily detectable by methods which over-simplify the ecological information, such as systems of indicator species and biotic indices, designed to assess the degree of pollution. The suitability of multivariate analysis and biotic indices in river phytoplankton studies is further discussed.     

Cytogenetic variability and differentiation in Artemia (Branchiopoda: Anostraca) populations from the Yucatán Peninsula,México

Chromosome numbers in somatic (naupliar) and germinal (adult male) cells of bisexual Artemia populations from the Yucatán Peninsula, SE México (Celestun, CEL; Chuburna, CHUB; Xtampu, XTAM; and Las Coloradas, COL), were compared to those from San Francisco Bay (SFB) and Great Salt Lake (GSL) individuals. Diploid and haploid counts permitted a double-check on results. SFB and GSL samples had low variability in number of chromosomes, with strong modal values of 2n=42 and n=21, typical for A. franciscana. Chromosome counts in the Yucatán brine shrimp samples indicated deviations from the normal 2n=42 karyotype (heteroploidy): COL had chromosome modes of 2n=42 and n=21; CEL of 2n=40 and n=20; CHUB had 2n=44 and n=22; XTAM 2n=48 and n=24. Chromocenter abundance (heterocromatic blocks of highly repetitive DNA) among populations indicated that the North American brine shrimp from SFB and GSL had a mean of 15.9 and 15.1 chromocenters, respectively. From the Yucatán brine shrimp, COL had a variable number of chromocenters, ranging from 5 to 15 with a mean value of 9.9. The other three Artemia populations had much fewer chromocenters (CEL 1–3, XTAM 1–8, and CHUB 1–4). Heteromorphic sex chromosomes were apparent in some Yucatán karyotypes preparations. The haplotype condition in the Yucatán Artemia populations, though similar to that found in some Italian A. salina populations, is reported for the first time in New World Artemia. This cytological characteristic of the Yucatán Artemia, in conjunction with their morphological and allozyme differentiation, could provide new insight for the role of chromosome rearrangements in the evolutionary process of Artemia in the New World.     

Seasonal succession of phytoplankton in a lake of the Paraná river floodplain,Argentina

Phytoplankton biomass, morphological and taxonomic composition, species diversity and productivity were analyzed in a shallow lake of the Middle Paraná River floodplain (El Tigre, 31 ° 41 S and 60° 42 W), between November 1986 and July 1988. Lake inundation (filling and through-flow phases) constituted an intense long-term perturbation in the physical and chemical environment. As the lake filled with river water, K-selected species (netplanktonic filamentous bluegreens, > 37 µm, with low surface area/volume (SA/V) ratios) that had existed prior to filling (late spring 1986) were replaced in summer-fall by r-selected species (nannoplanktonic chlorophytes and cryptophytes, < 37 µm, mainly stout forms with high SA/V ratios). During the through-flow phase, lentic phytoplankton was replaced by lotic flagellate populations due to the direct flushing by river water. During the period of falling water (drainage and isolation phases), nanoplanktonic algae with similar characteristics to those of the filling phase dominated in late winter-spring. Later in the isolation phase, these were succeeded by K-selected species (netplanktonic algae, mainly motile spherical dinoflagellates and filamentous bluegreens with low SA/V ratios). Simultaneously, primary production per unit biomass decreased and total biomass and specific diversity increased. Seasonal changes of phytoplankton in floodplain lakes can be interpreted as the interaction between true successional development (as observed in the drainage and isolation phases) and intermediate disturbance. Using Reynolds' terminology, short-term disturbance (slight inflow of nutrient-rich river water) caused reversion to an earlier stage in the former succession, and long-term disturbance (lake inundation) truncated the successional progression and a new (or shifted) succession was initiated.     

A new cucullanid from the black grouper Mycteroperca bonaci (Osteichthyes: Serranidae) off the coast of Yucatán, México

Cucullanus mycteropercae n. sp. is described from the intestine of the black grouper, Mycteroperca bonaci Poey, from the northern coast of Yucatán, México. The new species is readily distinguishable from other Cucullanus species because it possesses an ellipsoidal papilla-like structure situated medially on the anterior cloacal lip of males. Other differentiating characters include the variable position of postcloacal pair 8 in males, the subventral position of phasmids, a slightly ventrally hooked posterior end of gubernaculum, and the presence of a large, cylindroconical sclerotized tail end in both sexes. This is the fourth record of a marine cucullanid off the Yucatán Peninsula in México belonging to Cucullanus Müller, 1777.     

Seasonal fluctuations of zooplankton biomass in Lake Xolotlán (Managua)

Seasonal fluctuations of zooplankton biomass (dry weight) were determined during a year in two localities of Lake Xolotlán (Managua). Biomass estimations of the most common species of rotifers, cladocerans and copepods were made. The maximal zooplankton biomass was observed in February–April (dry season) in coincidence with the period of highest phytoplankton abundance. Copepods contributed with 78% and 84% to the mean zooplankton biomass at points 1 and 7, respectively. Cladocera biomass was lowest during most of the year, and it was probably controlled by fish predation. Development of rotifer biomass was more intense during the rainy season, when detritus particles were more abundant. Daily fluctuations of zooplankton biomass were not pronounced.     

Seasonal variations in the conception rate of beef cattle in the seasonal—equatorial climate of southern nigeria

Seasonal variations in the frequency of conceptions were analysed from the records of 8,971 beef calves born over a period of ten years (1959–1968) in the Southern Guinea Savannah of Nigeria. Mean annual and monthly conception rates were 72 and 6%, respectively. Highly significant changes in conception rates were observed: the highest number of conceptions occurred in April (7.3%) and the lowest in October (4.4%). The cubic function of the curve depicting the monthly conception rate was highly significant (p < 0.001) and parallelled the change in photoperiod (r = +0.39, p < 0.01). Conception rate was not related to either temperature or precipitation. The evidence suggests a photoperiodic influence on conception rates.

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Zusammenfassung Saisonale Schwankungen in der Konzeptionsrate von Fleischrindern der Guineasavanne Südnigerias wurden anhand von 8.971 Kalbungen aus zehn Jahren (1959–1968) untersucht. Die durchschnittlichen jährlichen und monatlichen Konzeptionsraten betrugen 72 beziehungsweise 6%; jedoch wurden hochsignifikante Abweichungen (p < 0.001) von dem monatlichen Mittelwert festgestellt: die höchste Konzeptionsrate wurde mit 7,3% für April, die niedrigste mit 4,4% für Oktober errechnet. Die mathematische Funktion der Konzeptionsrate folgt einer Sinuskurve, welche der monatlichen Veränderung der Tageslichtlänge parallel läuft (r = +0,39, p < 0.01). Die Konzeptionsrate war nicht mit der Durchschnittstemperatur oder den Niederschlägen korreliert. Diese Ergebnisse lassen vermuten, dass die saisonalen Schwankungen in der Konzeptionsrate zumindest teilweise auf photoperiodische Veränderungen zurückzuführen sind.

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Resume Les variations saisonnières du taux de fécondité de bovins de la savanne du sud de la Guinée (Nigéria) ont été étudiées sur la base de 8971 mises bas ayant eu lieu durant une période de 10 ans. Le taux de fécondité moyen fut de 72% pour l'année et de 6% pour chaque mois. On constate pourtant des différences significatives entre les différents mois: le taux le plus élevé se trouve en avril (7,3%) et le plus bas en octobre (4,4%). La fonction du troisième degré du taux de fécondité est hautement significative (p < 0,001). Elle suit une courbe sinusöidale parallèle à celle de la longueur du jour (r = +0,39, p < 0,01). Il n'y a pas de relation entre le nombre de conceptions et la température ou les précipitations. Par conséquent, seul le photopériodisme semble influencer le nombre des conceptions.

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The permission of the Western Nigeria Development Corporation to analyse and publish their breeding records is gratefully acknowledged.     

Re-infestation of houses by Triatoma dimidiata after intra-domicile insecticide application in the Yucatán peninsula, Mexico

In most countries, Chagas disease transmission control remains based on domestic insecticide application. We thus evaluated the efficacy of intra-domicile cyfluthrin spraying for the control of Triatoma dimidiata, the only Chagas disease vector in the Yucatán peninsula, Mexico, and monitored potential re-infestation every 15 days for up to 9 months. We found that there was a re-infestation of houses by adult bugs starting 4 months after insecticide application, possibly from sylvatic/peridomicile areas. This points out the need to take into account the potential dispersal of sylvatic/peridomestic adult bugs into the domiciles as well as continuity action for an effective vector control.