Lesser Antilles Research Articles

Gas Monitoring of Volcanic-Hydrothermal Plumes in a Tropical Environment: The Case of La Soufrière de Guadeloupe Unrest Volcano (Lesser Antilles)

Fumarolic gas survey of dormant volcanoes in hydrothermal activity is crucial to detect compositional and mass flux changes in gas emissions that are potential precursors of violent phreatic or even magmatic eruptions. Here we report on new data for the chemical compositions (CO2, H2S, SO2) and fluxes of fumarolic gas emissions (97–104°C) from La Soufrière volcano in Guadeloupe (Lesser Antilles) obtained from both mobile MultiGas measurements and permanent MultiGas survey. This paper covers the period 2016–2020, encompassing a period of enhanced hydrothermal unrest including an abrupt seismic energy release (M 4.1) on April 27, 2018. Our dataset reveals fumarolic CO2/H2S and SO2/H2S gas trends correlated to the evolution of surface activity and to other geochemical and geophysical parameters. We demonstrate that, even under tropical conditions (high humidity and rainfall), MultiGas surveys of low-T fumarolic emissions permit to distinguish deeply sourced signals of volcanic unrest from secondary changes in degassing due to shallow forcing processes such as water-gas-rock interactions in the hydrothermal system and meteorological effects.

Defining Fragmentation Patterns of Archaeological Bone Remains without Typologies: A Landmark-Based Approach on Rodent Mandibula

Fragmentation is a recurring feature of archaeological faunal material, and impacts many aspects of zooarchaeological studies from taxonomical identification to biometric studies. It can result from anthropic and natural actions that occurred respectively before and/or after bone deposit. While several bone fragmentation typologies have been described, they are currently based on both macroscopic observations and researcher subjectivity and lack the universality necessary for inter-study comparisons. To fulfill this need we present a standardized landmark-based protocol for the description and quantification of mandibular fragmentation patterns, using two insular rodents of different sizes as models. The rice rats (Oryzomyini tribe) and the agouti (Dasyprocta) from the Lesser Antilles were abundant during the pre-Columbian Ceramic Age (500 BCE-1500 CE). Their mandibles’ shapes were quantified using the coordinates of 13 2D-landmarks. We show that landmark-based measurements can be used to:—assess the preservation differences between taxa of the same taxonomic group (e.g., rodents),—estimate the level of preservation of a skeletal part (e.g., mandible),—describe fragmentation patterns without pre-existing typologies and—facilitate the application of geometric morphometric methods to fragmented archaeological material. Our novel approach, leveraging fragmentation analyses and establishing specific fragmentation patterns, frees itself from existing typologies and could be systematically applied to future research.

Iguanainsularis (Iguanidae) from the southern Lesser Antilles: An endemic lineage endangered by hybridization.

The newly described horned iguanaIguanainsularis from the southern Lesser Antilles is separated in two easily recognized subspecies: I.insularissanctaluciae from St. Lucia and I.insularisinsularis from the Grenadines. Its former description is completed by the use of 38 new samples for genetic and morphological analysis. Seventeen microsatellites were used to estimate genetic diversity, population structure and the level of introgression with other Iguana species over nearly the whole range of the species. ND4 and PAC sequences were also used to better characterize hybridization and to complete the description of this lineage. The I.insularis population of St. Vincent shows a high level of introgression from I.iguana whereas in the Grenadines, most islands present pure insularis populations but several show evidence of introgressions. Of the two remaining populations of I.insularissanctaluciae, only one is still purebred. The recent identification of this and other distinct insular species and subspecies in the eastern Caribbean, and evaluation of where hybridization has occurred, are timely and important because the native iguanas are in urgent need of conservation action. Among the greatest threats is the ongoing human-mediated spread of invasive iguanas from Central and South America, which are destroying the endemic insular lineages through multiple diachronic introgression events.

A Wrapper to Use a Machine-Learning-Based Algorithm for Earthquake Monitoring

AbstractSeismology is one of the main sciences used to monitor volcanic activity worldwide. Fast, efficient, and accurate seismicity detectors are crucial to assess the activity level of a volcano in near-real time and to issue timely warnings. Traditional real-time seismic processing software uses phase onset pickers followed by a phase association algorithm to declare an event and estimate its location. The pickers typically do not identify whether the detected phase is a P or S arrival, which can have a negative impact on hypocentral location quality and complicates phase association. We implemented the deep-neural-network-based method PhaseNet to identify in real time P and S seismic waves on data from one- and three-component seismometers. We tuned the Earthworm binder_ew associator module to use the phase identification from PhaseNet to detect and locate the events, which we archive in a SeisComP3 database. We assessed the performance of the algorithm by comparing the results with existing catalogs built to monitor seismic and volcanic activity in Mayotte and the Lesser Antilles region. Our algorithm, which we refer to as PhaseWorm, showed promising results in both contexts and clearly outperformed the previous automatic method implemented in Mayotte. This innovative real-time processing system is now operational for seismicity monitoring in Mayotte and Martinique.

Automatic picking and probabilistic location for earthquake assessment in the Lesser Antilles subduction zone (1972–2012)

Instrumental catalogues of earthquakes in the subduction zone of the Lesser Antilles are produced by local observatories and the International Seismological Centre. But none of these catalogues merge all arrival times of the first regional phases available; in addition, they have a magnitude of completeness relatively high for the entire Lesser Antilles area. As part of the Antilles Seismological Data Centre project, we produced a unified catalogue of known earthquakes from 1972 to 2012, with optimal constraints on the hypocentre locations. We re-evaluated the hypocentres with the method used in local observatories and a probabilistic method improving the distributions of arrival time residuals. We developed a simple method to select the preferred hypocentre independently of the localization algorithm, and we offer a complete catalogue including 46,703 earthquakes. Compared to other existing catalogues, we provide additional arrival times for 24,528 earthquakes. Our results highlight the variabilities of the magnitude of completeness and of the seismicity suggesting how the future analysis could infer the mechanisms of heterogeneous seismic coupling and intermediate-depth triggering.

Comparisons of habitat types and host tree species across a threatened Caribbean orchid’s core and edge distribution

AbstractTropical forest ecosystems are rich in epiphytes that make up a significant portion of the overall plant diversity. However, epiphytic plants are often understudied due to inaccessibility and the lack of basic ecological information poses challenges to their conservation, particularly in a time of rapid global change. The mule-ear orchid,Trichocentrum undulatum(Orchidaceae), is a large flowering epiphyte found in southern Florida (USA), the Greater, and Lesser Antilles including Cuba. The plant is Florida state-listed as endangered with only one remaining small and declining population in a coastal mangrove forest due to historical extraction and habitat destruction. Currently, there is no systematic understanding of the species’ habitat requirements. To fill this void, we compared the habitat and microhabitat of the species on its northern distribution edge (southern Florida) and the core range (in Cuba). The Florida population has only one host species,Conocarpus erectus, found in one habitat type. This is in sharp contrast to the 92 documented hosts and 5 habitats across 8 provinces in Cuba. Based on our findings from Cuba, we suggest conservation and restoration options in Florida by proposing potential suitable host plants and habitats. Proactive restoration of this species will help to ease the threat from sea-level rise to the species by securing and expanding range margins.

Ocean–atmosphere variability and drought in the insular Caribbean

AbstractThe insular Caribbean experiences numerous climate and environmental hazards, including but not limited to hurricanes, floods, earthquakes, and drought. While some hazards are well explored in scientific literature, drought is considered one of the neglected hazards because of the lack of studies focusing on its causes and effects. This study identifies the spatial distribution of seasonal drought in insular Caribbean from 1950 to 2017, and its relationship with eastern Pacific (EP) and central Pacific (CP) ENSO, North Atlantic Oscillation (NAO), and Atlantic Meridional Mode (AMM). It brings a new perspective over the region by dividing the Caribbean into Greater Antilles and Bahamas (GA), and the Lesser Antilles (LA) to compare the role of those three teleconnection patterns on drought events over larger versus smaller islands. We used an existing high‐resolution drought atlas (4 km) based on monthly estimates of the self‐calibrating Palmer Drought Severity Index (scPDSI). Results indicate that there is a drying trend in all seasonal‐average scPDSI for both the GA and the LA, but more intense and frequent drought events occur in the LA. The LA is also the region with more widespread drought events, registering 12 years when the mid‐summer dry spell (MSD; July–August) had drought ≥80% of the area, while the GA registered only 2 years of MSD drought that extensive. The peak season AMM had the strongest positive correlation with GA and LA drought during April–November, while NAO was slightly stronger correlated with GA than with LA from July–November. For ENSO, CP El Niño years related stronger with drought in the LA from December–July, while the relationship between the two types of ENSO and the GA was not statistically significant. This effort aims to improve drought forecasts to help the region to better prepare for the prediction of seasonal droughts.

Utilizing cores for characterising the temperature and permeability regimes in a litho-stratigraphic model of the Montserrat geothermal system, Montserrat (Lesser Antilles arc, West Indies)

Cores samples are vital in the characterization of heterogeneous volcanic geothermal environments. Continuous cored intervals, representative of the subsurface formation, can help to validate geological and thermal classifications previously interpreted from drill cuttings. More importantly, core samples can help to improve our understanding of controls on fluid flow, as direct permeability measurements are attainable. In this study, we conduct petrological and petrophysical analyses on three cores (Core 1, Core 2 and Core 3) obtained from the well MON-3, drilled within the hydrothermal system located in Montserrat, Lesser Antilles arc, West Indies. We present a litho-stratigraphic model of the geothermal system. Contrasting lithologies (sandstone, limestone and interbedded silicified tuff) and mineralogies (calcite vs plagioclase) from Core 3 (2109 – 2116.5 mbsl) contributed to constraining a volcanic-sedimentary unit (∼1900 – 2200 mbsl) while pumice textures of Core 1 (1478 – 1482.6 mbsl) and Core 2 (1700 – 1705.3 mbsl) helped to classify a subaerial volcanic unit (∼1200 – 1900 mbsl). Integrating classified alteration assemblages in the model with downhole temperature logs, we propose that the thermal regime of the hydrothermal system was hotter in the past based on evidence of epidote and actinolite observed at depths less than 1200 mbsl. Lastly, we infer that the primary permeability of carbonate formations or secondary fracture permeability developed by a SW and WNW fault zone in a shallower volcanic sedimentary unit (∼900 – 1200 mbsl) could be influences on potential feedzone locations in the wellbore. This could be supported by the relatively highest measured permeabilities (10−18 – 10−17 m2) in a carbonate sample of Core 3 and fractured samples of Core 2. Overall, the improved characterization of litho-units, alteration assemblages and permeable zones with possible influences on fluid flow, can be used to enhance previous numerical and geophysical models of Montserrat's geothermal system.

A Crustal Control on the Fe Isotope Systematics of Volcanic Arcs Revealed in Plutonic Xenoliths From the Lesser Antilles

Lavas produced at subduction zones represent the integration of both source heterogeneity and an array of crustal processes, such as: differentiation; mixing; homogenisation; assimilation. Therefore, unravelling the relative contribution of the sub-arc mantle source versus these crustal processes is difficult when using the amalgamated end products in isolation. In contrast, plutonic xenoliths provide a complementary record of the deeper roots of the magmatic plumbing system and provide a unique record of the true chemical diversity of arc crust. Here, we present the δ56Fe record from well characterised plutonic xenoliths from two distinct volcanic centres in the Lesser Antilles volcanic arc–the islands of Martinique and Statia. The primary objective of this study is to test if the Fe isotope systematics of arc lavas are controlled by sub-arc mantle inputs or during subsequent differentiation processes during a magma’s journey through volcanic arc crust. The Fe isotopic record, coupled to petrology, trace element chemistry and radiogenic isotopes of plutonic xenoliths from the two islands reveal a hidden crustal reservoir of heavy Fe that previously hasn’t been considered. Iron isotopes are decoupled from radiogenic isotopes, suggesting that crustal and/or sediment assimilation does not control the Fe systematics of arc magmas. In contrast to arc lavas, the cumulates from both islands record MORB-like δ56Fe values. In Statia, δ56Fe decreases with major and trace element indicators of differentiation (SiO2, Na2O + K2O, Eu/Eu*, Dy/Yb), consistent with fractionating mineral assemblages along a line of liquid descent. In Martinique, δ56Fe shows no clear relationship with most indicators of differentiation (apart from Dy/Yb), suggesting that the δ56Fe signature of the plutonic xenoliths has been overprinted by later stage processes, such as percolating reactive melts. Together, these data suggest that magmatic processes within the sub-arc crust overprint any source variation of the sub-arc mantle and that a light Fe source is not a requirement to produce the light Fe isotopic compositions recorded in volcanic arc lavas. Therefore, whenever possible, the complimentary plutonic record should be considered in isotopic studies to understand the relative control of the mantle source versus magmatic processes in the crust.

20th-century strain accumulation on the Lesser Antilles megathrust based on coral microatolls

The seismic potential of the Lesser Antilles megathrust remains poorly known, despite the potential hazard it poses to numerous island populations and its proximity to the Americas. As it has not produced any large earthquakes in the instrumental era, the megathrust is often assumed to be aseismic. However, historical records of great earthquakes in the 19th century and earlier, which were most likely megathrust ruptures, demonstrate that the subduction is not entirely aseismic. Recent occurrences of giant earthquakes in areas where such events were previously thought to be improbable have illustrated the importance of critically evaluating the seismic potential of other “low-hazard” subduction zones, such as the Lesser Antilles.Using the method of coral microatoll paleogeodesy developed in Sumatra, we examine 20th-century vertical deformation on the forearc islands of the Lesser Antilles and model the underlying strain accumulation on the megathrust. Our data indicate that the eastern coasts of the forearc islands have been subsiding by up to ∼8 mm/yr relative to sites closer to the arc, suggesting that on the time scale of the 20th century, a portion of the megathrust just east of the forearc islands has been locked. Our findings are in contrast to recent models based on satellite geodesy that suggest little or no strain accumulation anywhere along the Lesser Antilles megathrust. This discrepancy is potentially explained by the different time scales of measurement, as recent studies elsewhere have indicated that interseismic coupling patterns may vary on decadal time scales and that century-scale or longer records are required to fully assess seismic potential. The accumulated strain we have detected will likely be released in future megathrust earthquakes, uplifting previously subsiding areas and potentially causing widespread damage from strong ground motion and tsunami waves.

Creole and vernacular architecture: embryonic syncretism in Caribbean cultural landscape

Tracing across the complex histories of dominions and influences converging on the Caribbean territories, this paper examines certain common historic threads that persisted into the contemporary Caribbean cultural landscape and its architecture. As the largest English Caribbean island, Jamaica had one hundred and sixty-one years (1494–1655) of Spanish governance; and in the Lesser Antilles, Trinidad had two hundred and ninety-nine years (1498–1797). Drawing evidence from sixteenth- to mid-nineteenth-century archival iconography and documentation across the wider Americas, this paper identifies and discusses a common Caribbean urban and rural cultural landscape. By the 1834 English emancipation declaration from enslavement, this landscape acquired architectural syncretism at the encounter between the Indigenous buhio, or bohio, and the arrival of Columbus in 1492. This encounter has since then propelled creole and vernacular manifestations of distinct architectural forms from Indigenous, European, and African peoples across the period of plantation enslavement. Gottfried Semper displayed a Caribbean ‘hut’ from the island of Trinidad at the 1851 Great Exhibition in London, extending the syncretic manifestation from the ‘primitive hut’ architectural treatise to the birth of modern architecture. While ascribing the roots of these styles to Caribbean traditional architecture, this paper demonstrates the value of such architectonic syncretism and the connection with the development of modern architecture, and furthermore, the agenda of sustainable development.

Deux nouveaux longicornes de Martinique et divers signalements des Petites Antilles (Coleoptera, Cerambycidae)

Two new longhorn beetles from Martinique and various records from the Lesser Antilles (Coleoptera, Cerambycidae). A new species of Eburiini is described from Martinique: Pantomallus ravati Touroult & Deknuydt, n. sp. It is compared with the closely related species Pantomallus inermis Fleutiaux & Sallé, 1890, comb. rev. from Guadeloupe. Eburia decemmaculata (Fabricius, 1775) is reported for the first time from Barbados and its presence, until now doubtful, is confirmed in Martinique. A new Acanthocinini, Neseuterpia fiardi Touroult & Poirier, n. sp., is described from the rainforests of Montagne Pelée and compared with species from Guadeloupe and Dominica. Hypsioma grisea (Fleutiaux & Sallé, 1890) is reported for the first time from Saint-Martin.

Isotopic Niches of Coral Reef Fishes at Early Stages of Development on Guadeloupean Coral Reefs (Lesser Antilles)

Isotopic Niches of Coral Reef Fishes at Early Stages of Development on Guadeloupean Coral Reefs (Lesser Antilles)

The influence of the inter-tropical convergence zone on the Orinoco River and Late Quaternary tropical planktonic foraminiferal assemblages

Although deep-water oil and gas exploration offshore eastern Trinidad is becoming prevalent, the use of ecostratigraphy around eastern Trinidad are limited mostly to neritic water depths. Changes in planktonic foraminiferal assemblages of Core BGT086, offshore eastern Trinidad, are used here to indicate biozonal events useful for deep-water (>1000 m water depth) exploration. Decreased proportional abundances of Globigerinella obesa and Globigerina bulloides mark the southward migration of the inter-tropical convergence zone (ITCZ) during the Younger Dryas (YD). A decrease in species richness and Globigerinoides ruberwhite proportional abundance is consistent with rising temperature during the YD. During Biozone Z2, nutrient-preferring species (G. bulloides, Neogloboquadrina dutertrei) declined in proportional abundance, while G. ruberpink increased in proportional abundance, reflecting the arrival of the ITCZ in the area. Decreases in mean diversity (measured using the Shannon Function, H) and evenness (equitability index, E), and an increase in mean dominance (max pi) support the claim that the ITCZ arrived in the area after the YD. A sudden increase in Globorotalia menardii proportional abundance marked the start of Biozone Z1, at which time there was a change from a stressed community to a less stressed one. Boundaries of SHE abundance biozones coincided with noticeably enhanced assemblage changes, being consistent with the southward migration of the ITCZ and the onset of Biozone Z1. The mean value of the pairwise assemblage turnover index (ATIs) is here used as a proxy for what we term 'assemblage stability'. Comparisons of mean planktonic foraminiferal ATIs from Core BGT086 and six other nearby tropical piston cores (Cores 1, 2 and 3 off NW Tobago, and En20-2, En20-10 and En20-16 from the Leeward Islands, Lesser Antilles) showed no statistical difference in assemblage stabilities within similar planktonic foraminiferal biozones. Kruskal-Wallis tests determined a significant difference in median ATIs values when all seven cores' ATIs were used, but the difference was not significant when data above the YD boundary (i.e., Biozone Z) were used. The lowered nutrient influx from the Orinoco River due to the arrival of the ITCZ in the area after the YD would have triggered a stable environment for planktonic foraminiferal assemblages. This implies that caution must be used to ensure data from the same biozone is used when analyzing assemblage stabilities of planktonic foraminifera.

Morphological Variation in the Martinican Subspecies White-Breasted Thrasher (<i>Ramphocinclus brachyurus brachyurus</i>)

The White-breasted Thrasher (Ramphocinclus brachyurus) is the smallest passerine bird in the Mimids family. Ranked as “endangered” in the IUCN list, the demographic distribution of this species is spread unevenly across two islands in the Lesser Antilles. The Saint-Lucian subspecies, Ramphocinclus brachyurus sanctaeluciae, was estimated to number between 1200 and 1700 individuals, whereas the Martinique subspecies, Ramphocinclus brachyurus brachyurus, was estimated at between 200 and 400 individuals. As an endemic rare species with a high risk of extinction, the Martinique subspecies should be regarded as a conservation priority. The small size of the Martinique subspecies population, its restricted geographical range, and its narrow habitat tolerance make it quite difficult to study. The variability of morphological traits in this subspecies has not been biostatistically analyzed recently. In order to update knowledge and fill in any gaps, we have used the morphometric approach to study the morphological variability of the Martinique subspecies. The study site is a small peninsula located in the northeast of the island of Martinique (French West Indies) known as “la Caravelle”. We captured 63 White-breasted Thrashers which were marked, measured, and sexed before being released. We did not observe any significant differences between the sexes, signifying an absence of sexual dimorphism. However, we were able to observe a significant variation in morphological traits between individuals measured inside and outside the national protected area of Caravelle. The body mass-tarsus ratio was equal at both sampled sites, something which could potentially be a clue to the bird’s adaptation to different habitats.

A New Versatile Method for the Reconstruction of Scintillator-Based Muon Telescope Events

This paper presents a new method to process the data recorded with muon telescopes. We have developed this processing method for the plastic scintillator-based hodoscopes located around the volcano La Soufri\`ere de Guadeloupe, in the French Lesser Antilles, in order to perform muon radiographies of the lava dome region, strongly impacted by the volcanic hydrothermal activity. Our method relies on particle trajectory reconstruction, performing a fit of the recorded hits in the impacted scintillator bars using a Random Sample Consensus algorithm. This algorithm is specifically built to discriminate outlier points, usually due to noise hits, in the data. Thus, it is expected to significantly improve the signal/noise separation in muon track hits and to obtain higher quality estimates of the particles' incident trajectories in our detectors. The first analysis of the RANSAC-reconstructed events offers promising results in terms of average density maps. To illustrate the performances of this algorithm, we provide angular resolution and reconstruction efficiency estimates using a GEANT4 simulation of a telescope equipped with four detection matrices. In addition, we also show preliminary results from open-sky data recorded with such telescope at La Soufri\`ere de Guadeloupe volcano.

Paleogeography of the Central Lesser Antilles Since the Early Miocene: Onshore-Offshore Correlations

Paleogeography of the Central Lesser Antilles Since the Early Miocene: Onshore-Offshore Correlations

“Never visited a colony where negroes had such courage”. Dutch colonial ethos in Curaçao

The subject of this research is the initial stage of the Dutch colonization of one of the Lesser Antilles, Curacao, which is today a subject of the Federation in the Kingdom of the Netherlands. In Russian historiography, the role of Curacao as the largest smuggling center of the eighteenth century is practically not disclosed. The article examines the events of the 17th – 18th centuries. Taking into account the Dutch historical canon, the features of the Dutch colonial ethos in the context of a non-plantation economic system are described. The authors consider such aspects of the topic as the formation of the island as a transit center for transatlantic trade, as well as the role of slaves in its economic development. The work is based on the principles of historicism, consistency, objectivity. The methodological basis of the research is the historical-genetic method, which allows to show the considered reality in its historical development. Despite the milder conditions of exploitation of slaves, numerous cases of escape and unrest of slaves are known. A characteristic feature of Curacao was the presence in all economic spheres of free blacks and mulattoes, mainly due to the urban economy.

Investigating Past and Present Carpometacarpus Morphology in Mimidae: A Multi-Methods Approach to Evidence from the Guadeloupe Islands

Past bird communities are still under-studied in several Caribbean regions, including the Lesser Antilles. In order to improve our understanding of this area’s avifauna, we explore morphometrical variations of the carpometacarpus (CMC) within West Indies Mimidae species. We combine geometric morphometric (GMM) and conventional osteology focusing on characters of the entire or distal portion of the CMC. Morphological variation related to their phylogenetic history is investigated using uni- and multi-variate statistics, and the expression of certain osteological characters. Fossil bone remains from the Guadeloupe Islands were included in the datasets to test the applicability of these results to the archaeological and paleontological record.Our results are consistent with the known phylogeny of Mimidae. The GMM analysis clearly differentiated taxa at both inter- and intra-generic levels, which when combined with osteological characters, allow fossil specimens to be determined to species. For the fossil record of Guadeloupe Islands, this concerns three taxa: the Scaly-breasted Thrasher Allenia fusca, the Gray Catbird Dumetella carolinensis, the first fossil occurrence of this bird in the Greater and Lesser Antilles, and the Brown Trembler Cinclocerthia ruficauda in Desirade and Marie-Galante, where the bird is now extirpated. These results are of particular interest for tracking the impact of environmental changes on the composition of West Indian bird communities.

Geodispersal of the Typical Neotropical cenocron from South America to the Mexican Transition Zone: a cladistic biogeographical test

Abstract Analysis of the biotic assembly of the Mexican Transition Zone (MTZ) is challenging because of the convergence of taxa with different origins and biogeographical histories. The typical Neotropical cenocron corresponds to genera widespread in South America that might have dispersed to the MTZ in the Pliocene–Holocene. It has been exemplified with distributional patterns of several plant and animal taxa; however, their historical congruence has not been tested. We examined the historical relationships among the areas of endemism where Typical Neotropical taxa are found through a cladistic biogeographical analysis to determine whether they have dispersed simultaneously, showing a geodispersal pattern. We searched for Neotropical clades that dispersed to the MTZ from the Pliocene to the present. The distribution of nine animal clades in seven areas of endemism was analysed by cladistic biogeography. Redundant areas and widespread taxa were treated with paralogy-free and transparent methods. Patterns of area relationships were searched using a parsimony analysis of paralogy-free subtrees. The parsimony analysis found a single resolved tree showing a general pattern of area relationships: (Chacoan ((South Brazilian (Boreal Brazilian + Lesser Antilles)), (South American Pacific (Mesoamerican-Central America + Western Mexico)))). Distributional and phylogenetic information on the groups analysed contrast with a previous cladistic biogeographical analysis that has shown different area relationships, thus supporting the general hypothesis of a geodispersal event of the Typical Neotropical cenocron in the MTZ. Additionally, the analysis provided evidence of vicariant events related to the lifting of the Northern Andes and climatic changes during the Pleistocene.