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Aim The widespread megadiverse Neotropical snake family Dipsadidae occurs in a large range of diverse habitats. Therefore, it represents an excellent model to study the diversification of Neotropical biota. Herein, by generating a time-calibrated species-level phylogeny, we investigate the origin and historical biogeography of Dipsadidae and test if its two main Neotropical subfamilies, Xenodontinae and Dipsadinae, have different geographical origins. Location Neotropical region. Taxon Dipsadidae (Serpentes). Methods We generated a new Bayesian time-calibrated phylogeny based on published sequences from six genes for 344 species, including 287 species of Dipsadidae. We subsequently estimated ancestral areas of distribution by comparing models in BioGeoBEARS: DEC (subset sympatry, narrow vicariance), DIVALIKE (narrow and wide vicariance), BAYAREALIKE (no vicariance and widespread sympatry), also testing jump dispersal. We also estimated shifts in the diversification of this group using BAMM, exploring possible relationships with its historical biogeography. Results The best models show that Dipsadidae likely originated approximately 50 million years ago (mya) in Asia. Dispersal was a fundamental process in its historical biogeography. The DEC model with jump dispersal indicated that this family underwent a range extension from Asia and posterior vicariance of North and Central America ancestors. Both Xenodontinae and Dipsadinae originated in Central America and dispersed to South America during Middle Eocene, but did so to different regions (cis and trans-Andean South America, respectively). Xenodontinae entered cis-Andean South America around 39 mya and jump dispersed to the West Indies around 33 mya, while Dipsadinae entered trans-Andean South America multiple times 20–38 mya. The diversification rate decreased through time, except for a clade within Dipsadinae composed of the Dipsadini tribe and the Atractus and Geophis genera. Main Conclusions Our results show that Dipsadidae has an Asian origin and that the two main Neotropical subfamilies originated in Central America, later dispersing to South America in different time periods. This difference is also reflected in the higher diversification rate for the ‘goo-eaters’ in the Dipsadinae subfamily. The current biogeographical patterns of the family Dipsadidae, the most species-rich snake family in the world, have likely been shaped by complex evolutionary and geological processes such as Eocene land bridges, Andean uplift and the formation of the Panama isthmus.

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The Cinchona genus is important for humanity due to its ethnobotanical properties, and in particular its ability to prevent and treat malaria. However, there have been historical changes of Cinchona distribution in the tropical Andes that remain undocumented. In the late eighteenth and early nineteenth centuries, several explorers recorded Cinchona precise localities in present-day Colombia and Ecuador, countries which harbour about half of the species of the genus, including C. officinalis. We compare historical and twentieth-century records to evaluate whether elevational ranges, mean elevation and latitude varied between the two periods. A large expansion of 662.5 m in average elevation for Cinchona and 792.5 m in elevational range for C. officinalis was found. These findings have implications for the conservation of economically important species and help us understand the impacts of the Anthropocene over time.

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The Chilean fauna of water bugs comprises seven species of semi-aquatic bugs (Heteroptera: Gerromorpha), representing five genera, three tribes, four subfamilies and four families; and 27 species and one subspecies of aquatic bugs (Heteroptera: Nepomorpha), representing four subgenera, eight genera, three tribes, seven subfamilies, and five families. We compare the fauna with neighboring countries and find that several otherwise widespread and abundant taxa are missing in Chile, but that Chepuvelia usingeri China, 1963 (Macroveliidae), Microvelia chilena Drake Hussey, 1955 (Veliidae), Limnocoris dubiosus Montandon, 1898 (Naucoridae), Nerthra (Nerthra) parvula (Signoret, 1863), N. (N.) undosa Nieser Chen, 1992, N. (Rhinodermacoris) praecipua Todd, 1957 (Gelastocoridae), and Sigara (Tropocorixa) termasensis (Hungerford, 1928a) (Corixidae) are endemic to the country. To this list, we add †Nerthra (Nerthra) subantarctica Faúndez Ashworth, 2015, even though the species is only known from a subfossil. We can also inform that while water bugs are found in the archipelagoes of southern Chile, no species has been reported from the Juan Fernandez Islands, Easter Island and other off-shore islands. Several of the Chilean species are without any close extant relatives, such as C. usingeri and Aquarius chilensis (Berg, 1881) (Gerridae), or with relatives in Oceania (N. praecipua), suggesting that historical events such as dispersal and extinction have had a major influence on the composition of the Chilean fauna.

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In this paper, we describe a new subfamily of Gonyleptidae, Paragoniosomatinae subfam. nov., based on a new genus and species, Paragoniosoma cachaceiro gen. nov., sp. nov., found in an upper montane cloud forest of Chapada Diamantina mountains, one of the small interior patches of Atlantic Forest. This discovery suggests that the narrow-restricted cloud forests are old relicts of an Atlantic Forest hotspot. Paragoniosoma cachaceiro gen. nov., sp. nov. is characterized by the presence of four areas on the dorsal scutum, serose dry mark in areas III-IV, seven basal setae in penis (macrosetae A and B) in two rows, and very large tarsal process. We performed a phylogenetic analysis based on morphological characters that revealed a close relationship of the new species with Goniosomatinae, a subfamily that includes six genera and 38 valid species distributed throughout the coastal Atlantic Forest. The new species also has the same habitat and other behavioural and ecological traits as Goniosomatinae, furnishing great insights on the evolution of their characteristic biology, e.g., subsocial behavior. Field surveys of harvestmen from the type locality and nearby lowland seasonal forests indicate a unique fauna, including additional new, undescribed species. In addition to phylogenetics, this dissimilarity with other regions and the presence of endemic species of other animal and plant taxa provide support for the consideration of the cloud montane patches of Chapada Diamantina as relicts. We discuss this rule in the historical biogeographic context of Atlantic Forest and suggest that the new species represents evidence of an Atlantic Forest that was more widespread in the past.

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Colletes Latreille (Hymenoptera: Colletidae) is a diverse genus with 518 valid species distributed in all biogeographic realms, except Australasia and Antarctica. Here we provide a comprehensive dated phylogeny for Colletes based on Bayesian and maximum likelihood-based analyses of DNA sequence data of six loci: 28S rDNA, cytochrome c oxidase subunit 1, elongation factor-1α copy F2, long-wavelength rhodopsin, RNA polymerase II and wingless. In total, our multilocus matrix consists of 4824 aligned base pairs for 143 species, including 112 Colletes species plus 31 outgroups (one stenotritid and a diverse array of colletids representing all subfamilies). Overall, analyses of each of the six single-locus datasets resulted in poorly resolved consensus trees with conflicting phylogenetic signal. However, our analyses of the multilocus matrix provided strong support for the monophyly of Colletes and show that it can be subdivided into five major clades. The implications of our phylogenetic results for future attempts at infrageneric classification for the Colletes of the world are discussed. We propose species groups for the Neotropical species of Colletes, the only major biogeographic realm for which no species groups have been proposed to date. Our dating analysis indicated that Colletes diverged from its sister taxon, Hemicotelles Toro and Cabezas, in the early Oligocene and that its extant lineages began diversifying only in the late Oligocene. According to our biogeographic reconstruction, Colletes originated in the Neotropics (most likely within South America) and then spread to the Nearctic very early in its evolutionary history. Geodispersal to the Old World occurred soon after colonization of the Northern Hemisphere. Lastly, the historical biogeography of Colletes is analyzed in light of available geological and palaeoenvironmental data.

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Knowledge on the hydrological evolution of the Neotropical region was used along with the current distribution of the anablepid species to investigate the historical biogeography of this family. Areas of endemism were delimited by endemicity analysis resulting in seven individual areas of endemism and three consensus areas located in northwestern Argentina, southern Brazil, and northern South America. These areas were discussed in the context of anablepid species diversification, especially for the genus Anableps and the subgenera Jenynsia and Plesiojenynsia. The existence of areas of endemism for the family analyzed reveals an intimate association with historical events that occurred in the geological evolution of South America, which can be associated with the main diversification patterns and historical hypotheses in the context of Neotropical freshwater fishes biogeography.

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Widespread fish clades that occur mainly or exclusively in fresh water represent a key target of biogeographical investigation due to limited potential for crossing marine barriers. Timescales for the origin and diversification of these groups are crucial tests of vicariant scenarios in which continental break-ups shaped modern geographic distributions. Evolutionary chronologies are commonly estimated through node-based palaeontological calibration of molecular phylogenies, but this approach ignores most of the temporal information encoded in the known fossil record of a given taxon. Here, we review the fossil record of freshwater fish clades with a distribution encompassing disjunct landmasses in the southern hemisphere. Palaeontologically derived temporal and geographic data were used to infer the plausible biogeographic processes that shaped the distribution of these clades. For seven extant clades with a relatively well-known fossil record, we used the stratigraphic distribution of their fossils to estimate confidence intervals on their times of origin. To do this, we employed a Bayesian framework that considers non-uniform preservation potential of freshwater fish fossils through time, as well as uncertainty in the absolute age of fossil horizons. We provide the following estimates for the origin times of these clades: Lepidosireniformes [125-95 million years ago (Ma)]; total-group Osteoglossomorpha (207-167 Ma); Characiformes (120-95 Ma; a younger estimate of 97-75 Ma when controversial Cenomanian fossils are excluded); Galaxiidae (235-21 Ma); Cyprinodontiformes (80-67 Ma); Channidae (79-43 Ma); Percichthyidae (127-69 Ma). These dates are mostly congruent with published molecular timetree estimates, despite the use of semi-independent data. Our reassessment of the biogeographic history of southern hemisphere freshwater fishes shows that long-distance dispersals and regional extinctions can confound and erode pre-existing vicariance-driven patterns. It is probable that disjunct distributions in many extant groups result from complex biogeographic processes that took place during the Late Cretaceous and Cenozoic. Although long-distance dispersals likely shaped the distributions of several freshwater fish clades, their exact mechanisms and their impact on broader macroevolutionary and ecological dynamics are still unclear and require further investigation.

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Aim A number of processes can lead to weak or conflicting phylogenetic signals, especially in geographically dynamic regions where unstable landscapes and climates promote complex evolutionary histories. The Middle American pitviper genus Bothriechis has a complex biogeographic distribution and previous phylogenetic analyses have recovered conflicting topologies based on the data type used. Here, we tested whether historic conflicts in the phylogeny were the result of reticulate evolution and whether the inferred biogeographic history of the group would enable contact among reticulate lineages.Location Middle America. Taxon Palm-pitvipers (genus Bothriechis). Methods We generated a phylogenomic dataset using an anchored phylogenomics approach and inferred a genomics-based species tree and mitochondrial tree to assess incongruence among datasets. We then generated a dated phylogeny and conducted ancestral area reconstruction to examine the biogeographic history surrounding the diversification of these species. We additionally tested whether the discordance among trees is better explained by lineage sorting or reticulate evolution by testing models of reticulate evolution inferred through multiple methods. Results We found strong support for discordance in the phylogeny of Bothriechis and corresponding evidence for reticulate evolution among lineages with incongruent placement. Ancestralarea reconstruction placed these taxa in adjacent regions during the time period when reticulation was projected to take place and suggested a biogeographic history heavily influenced by vicariant processes. Main conclusions Reticulation among geographically proximate lineages has driven apparent genomic discordance in Bothriechis and is responsible for historical incongruence in the phylogeny. Inference of the order of events suggests that reticulation among nuclear Middle American taxa occurred during a time of geologic upheaval, promoting lineage divergence and secondary contact. Reticulate evolution and similar processes can have substantial impacts on the evolutionary trajectory of taxa and are important to explicitly test for in biogeographically complex regions.

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Although the importance of biogeography in the speciation process is well recognized, the fundamental role of geographic diversification during adaptive radiations has not been studied to determine its importance during the adaptive radiation process. We examined the relationship between lineage and regional diversification patterns in the South American rodent subfamily Sigmodontinae, one of the best candidates for an adaptive radiation in mammals, to propose a conceptual framework for geographic transitions during adaptive radiations. We reconstructed a time-calibrated phylogeny from four nuclear genes and one mitochondrial gene for 77% of sigmodontine diversity. Historical biogeography was reconstructed among 14 regions, for which we applied a sliding-window approach to estimate regional transition rates through time. We compared these rate patterns and measured whether regions consisted of species that were more phylogenetically related than expected by chance. Following the initial South American colonization around 7 million years ago, multiple expansions from northern regions correlated with a burst of speciation. Subsequently, both diversification and regional transition rates decreased overall and within the majority of regions. Despite high regional transition rates, nearly all regional assemblages were phylogenetically clustered, indicating that within-region diversification was common. We conclude that biogeographic complexity and partitioning played a profound role in the adaptive radiation of the South American Sigmodontinae (Oryzomyalia), the degree to which is determined by the relative scales of spatial variation and dispersal abilities.

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Pleurodires or side-necked turtles are today restricted to freshwater environments of South America, Africa-Madagascar and Australia, but in the past they were distributed much more broadly, being found also on Eurasia, India and North America, and marine environments. Two hypotheses were proposed to explain this distribution; in the first, vicariance would have shaped the current geographical distribution and, in the second, extinctions constrained a previously widespread distribution. Here, we aim to reconstruct pleurodiran biogeographic history and diversification patterns based on a new phylogenetic hypothesis recovered from the analysis of the largest morphological dataset yet compiled for the lineage, testing which biogeographical process prevailed during its evolutionary history. The resulting topology generally agrees with previous hypotheses of the group and shows that most diversification shifts were related to the exploration of new niches, e.g. littoral or marine radiations. In addition, as other turtles, pleurodires do not seem to have been much affected by either the Cretaceous-Palaeogene or the Eocene-Oligocene mass extinctions. The biogeographic analyses highlight the predominance of both anagenetic and cladogenetic dispersal events and support the importance of transoceanic dispersals as a more common driver of area changes than previously thought, agreeing with previous studies with other non-turtle lineages.

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Using track analysis and cladistic biogeography, we identified areas of endemism of hummingbirds in the Andean and Neotropical regions. Our results point out that the current areas of endemism of hummingbirds occur in the Andes, Guiana Shield, the Lesser Antilles, western Central and North America and the Chiapas Highlands. The cladistic biogeographic analysis suggests a hummingbird distribution shaped mainly by dispersal events.(AU)

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Using track analysis and cladistic biogeography, we identified areas of endemism of hummingbirds in the Andean and Neotropical regions. Our results point out that the current areas of endemism of hummingbirds occur in the Andes, Guiana Shield, the Lesser Antilles, western Central and North America and the Chiapas Highlands. The cladistic biogeographic analysis suggests a hummingbird distribution shaped mainly by dispersal events.

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Aim To examine historical connections between rain forest habitats in the Neotropics based on the evolutionary history of the arboreal pit viper Bothrops bilineatus. Location Amazonia and Atlantic Forest in South America. Methods We inferred phylogenetic relationships within Bothrops and phylogeographic relationships within B. bilineatus using both concatenated and species tree approaches under a Bayesian framework based on four mitochondrial and five nuclear genes. We inferred demographic history within B. bilineatus based on tests of alternative historical scenarios using coalescent simulations and Approximate Bayesian Computation. Results Phylogenetic analyses recovered four major clades within Bothrops bilineatus. The best-fit historical scenario involved colonization of the Atlantic Forest by an Amazonian ancestor around 2 Mya, followed by range expansion in the Atlantic Forest. Subsequently, there was a colonization event into the Guiana Shield from an Atlantic Forest ancestor, dating back to around 0.3 Mya. Main conclusion The complex demographic history of Bothrops bilineatus shows multiple connection events between Amazonia and the Atlantic Forest in the last 2 million years. Two previously hypothesized forest bridges, southern and northeastern, may have been involved in range expansions in this species. These results shed light on the historical processes involved in the diversification of this venomous South American snake, providing information about the historical dynamism of forested habitats in the Neotropics.

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BACKGROUND AND AIMS: Maclura (ca. 12spp., Moraceae) is a widespread genus of trees and woody climbers found on five continents. Maclura pomifera, the Osage orange, is considered a classic example of an anachronistic fruit. Native to the central USA, the grapefruit-sized Osage oranges are unpalatable and have no known extant native dispersers, leading to speculation that the fruits were adapted to extinct megafauna. Our aim was to reconstruct the phylogeny, estimate divergence dates, and infer ancestral ranges of Maclura in order to test the monophyly of subgeneric classifications and to understand evolution and dispersal patterns in this globally distributed group. METHODS: Employing Bayesian and maximum-likelihood methods, we reconstructed the Maclura phylogeny using two nuclear and five chloroplast loci from all Maclura species and outgroups representing all Moraceae tribes. We reconstructed ancestral ranges and syncarp sizes using a family level dated tree, and used Ornstein-Uhlenbeck models to test for significant changes in syncarp size in the Osage orange lineage. KEY RESULTS: Our analyses support a monophyletic Maclura with a Paleocene crown. Subgeneric sections were monophyletic except for the geographically-disjunct Cardiogyne. There was strong support for current species delineations except in the widespread M. cochinchinensis. South America was reconstructed as the ancestral range for Maclura with subsequent colonization of Africa and the northern hemisphere. The clade containing M. pomifera likely diverged in the Oligocene, closely coinciding with crown divergence dates of the mammoth/mastodon and sloth clades that contain possible extinct dispersers. The best fitting model for syncarp size evolution indicated an increase in both syncarp size and the rate of syncarp size evolution in the Osage orange lineage. CONCLUSIONS: We conclude that our findings are consistent with the hypothesis that M. pomifera was adapted to dispersal by extinct megafauna. In addition, we consider dispersal rather than vicariance to be most likely responsible for the present distribution of Maclura, as crown divergence post-dated the separation of Africa and South America. We propose revised sectional delimitations based on the phylogeny. This study represents a complete phylogenetic and biogeographic analysis of this globally distributed genus and provides a basis for future work, including a taxonomic revision.

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Species richness in freshwater bony fishes depends on two main processes: the transition into and the diversification within freshwater habitats. In contrast to bony fishes, only few cartilaginous fishes, mostly stingrays (Myliobatoidei), were able to colonize fresh water. Respective transition processes have been mainly assessed from a physiological and morphological perspective, indicating that the freshwater lifestyle is strongly limited by the ability to perform osmoregulatory adaptations. However, the transition history and the effect of physiological constraints on the diversification in stingrays remain poorly understood. Herein, we estimated the geographic pathways of freshwater colonization and inferred the mode of habitat transitions. Further, we assessed habitat-related speciation rates in a time-calibrated phylogenetic framework to understand factors driving the transition of stingrays into and the diversification within fresh water. Using South American and Southeast Asian freshwater taxa as model organisms, we found one independent freshwater colonization event by stingrays in South America and at least three in Southeast Asia. We revealed that vicariant processes most likely caused freshwater transition during the time of major marine incursions. The habitat transition rates indicate that brackish water species switch preferably back into marine than forth into freshwater habitats. Moreover, our results showed significantly lower diversification rates in brackish water lineages, whereas freshwater and marine lineages exhibit similar rates. Thus, brackish water habitats may have functioned as evolutionary bottlenecks for the colonization of fresh water by stingrays, probably because of the higher variability of environmental conditions in brackish water.

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Despite their complex evolutionary history and the rich fossil record, the higher level phylogeny and historical biogeography of living turtles have not been investigated in a comprehensive and statistical framework. To tackle these issues, we assembled a large molecular dataset, maximizing both taxonomic and gene sampling. As different models provide alternative biogeographical scenarios, we have explicitly tested such hypotheses in order to reconstruct a robust biogeographical history of Testudines. We scanned publicly available databases for nucleotide sequences and composed a dataset comprising 13 loci for 294 living species of Testudines, which accounts for all living genera and 85% of their extant species diversity. Phylogenetic relationships and species divergence times were estimated using a thorough evaluation of fossil information as calibration priors. We then carried out the analysis of historical biogeography of Testudines in a fully statistical framework. Our study recovered the first large-scale phylogeny of turtles with well-supported relationships following the topology proposed by phylogenomic works. Our dating result consistently indicated that the origin of the main clades, Pleurodira and Cryptodira, occurred in the early Jurassic. The phylogenetic and historical biogeographical inferences permitted us to clarify how geological events affected the evolutionary dynamics of crown turtles. For instance, our analyses support the hypothesis that the breakup of Pangaea would have driven the divergence between the cryptodiran and pleurodiran lineages. The reticulated pattern in the ancestral distribution of the cryptodiran lineage suggests a complex biogeographic history for the clade, which was supposedly related to the complex paleogeographic history of Laurasia. On the other hand, the biogeographical history of Pleurodira indicated a tight correlation with the paleogeography of the Gondwanan landmasses.

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BACKGROUND: The evolution of South American Mabuyinae skinks holds significant biogeographic interest because its sister lineage is distributed across the African continent and adjacent islands. Moreover, at least one insular species, Trachylepis atlantica, has independently reached the New World through transoceanic dispersal. To clarify the evolutionary history of both Neotropical lineages, this study aimed to infer an updated timescale using the largest species and gene sampling dataset ever assembled for this group. By extending the analysis to the Scincidae family, we could employ fossil information to estimate mabuyinae divergence times and carried out a formal statistical biogeography analysis. To unveil macroevolutionary patterns, we also inferred diversification rates for this lineage and evaluated whether the colonization of South American continent significantly altered the mode of Mabuyinae evolution. METHODS: A time-calibrated phylogeny was inferred under the Bayesian framework employing fossil information. This timetree was used to (i) evaluate the historical biogeography of mabuiyines using the statistical approach implemented in BioGeoBEARS; (ii) estimate macroevolutionary diversification rates of the South American Mabuyinae lineages and the patterns of evolution of selected traits, namely, the mode of reproduction, body mass and snout-vent length; (iii) test the hypothesis of differential macroevolutionary patterns in South American lineages in BAMM and GeoSSE; and (iv) re-evaluate the ancestral state of the mode of reproduction of mabuyines. RESULTS: Our results corroborated the hypothesis that the occupation of the South American continent by Mabuyinae consisted of two independent dispersion events that occurred between the Oligocene and the Miocene. We found significant differences in speciation rates between the New World and the remaining Mabuyinae clades only in GeoSSE. The influence of phenotypic traits on diversification rates was not supported by any method. Ancestral state reconstruction suggested that the ancestor of South American mabuyine was likely viviparous. DISCUSSION: Our analyses further corroborated the existence of a transoceanic connection between Africa and South America in the Eocene/Oligocene period (Atlantogea). Following colonization of the isolated South America and subsequent dispersal through the continent by the ancestral mabuyine stock, we detected no difference in macroevolutionary regimes of New World clades. This finding argued against the ecological opportunity model as an explanation for the diversity of living mabuyines.

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We document patterns of coordinated dispersal over evolutionary time frames in heroine cichlids and poeciliine live-bearers, the two most species-rich clades of freshwater fishes in the Caribbean basin. Observed dispersal rate (DO) values were estimated from time-calibrated molecular phylogenies in Lagrange+, a modified version of the ML-based parametric biogeographic program Lagrange. DO is measured in units of "wallaces" (wa) as the number of biogeographic range-expansion events per million years. DO estimates were generated on a dynamic paleogeographic landscape of five areas over three time intervals from Upper Cretaceous to Recent. Expected dispersal rate (DE) values were generated from alternative paleogeographic models, with dispersal rates proportional to target area and source-river discharge volume, and inversely proportional to paleogeographic distance. Correlations between DO and DE were used to assess the relative contributions of these three biogeographic parameters. DO estimates imply a persistent dispersal corridor across the Eastern (Antillean) margin of the Caribbean plate, under the influence of prevailing and perennial riverine discharge vectors such as the Proto-Orinoco-Amazon river. Ancestral area estimation places the earliest colonizations of the Greater Antilles and Central America during the Paleocene-Eocene (ca. 58-45 Ma), potentially during the existence of an incomplete Paleogene Arc (∼59 Ma) or Lesser Antilles Arc (∼45 Ma), but predating the GAARlandia land bridge (∼34-33 Ma). Paleogeographic distance is the single best predictor of DO. The Western (Central American) plate margin did not serve as a dispersal corridor until the Late Neogene (12-0 Ma), and contributed relatively little to the formation of modern distributions.

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A revision of the avian Neotropical genus Automolus and the Furnariidae family points to the paraphyly of A. infuscatus and reveals a species complex comprising A. infuscatus, A. ochrolaemus, A. paraensis, A. leucophthalmus, A. lammi and A. subulatus, the latter historically classified in the genus Hyloctistes. Detailed knowledge of the taxonomy, geographic distribution, phylogenetic relationship and divergence times of a taxon allows exploration of its evolutionary history and the testing of different scenarios of diversification. In this context, we studied the A. infuscatus complex using molecular data in order to unveil its cryptic diversity and reveal its evolutionary history. For that we sequenced two mitochondrial (ND2 and cytb) and three nuclear markers (G3PDH, ACO, Fib7) for 302 individuals belonging to all species in the complex and most described subspecies. Our analysis supports the paraphyly of A. infuscatus, indicating the existence of at least two distinct clades not closely related. The remaining species were all recovered as monophyletic. Notwithstanding, a well-structured intraspecific diversity was found with 19 lineages suggesting substantial cryptic diversity within the described species. A. subulatus was recovered within the complex, corroborating its position inside the genus. In spite of the high congruence between distributions of different lineages, with several sister lineages currently separated by the same barriers, the temporal incongruence between divergences over the same barriers reveals a complex evolutionary history. While older events might be related to the emergence of barriers such as the Andes and major Amazonian rivers, younger events suggest dispersal after the consolidation of those barriers. Our analysis suggests that the complex had its origin around 6million years (Ma) and inhabited Western Amazonia in Late Miocene-Early Pliocene. Considering the riparian habit of species in its sister clade, the rise and early diversifications of the complex may be related to the establishment of terra firme forests as it changed from a floodplain to a fluvial system. The late Amazonian colonization by A. subulatus and A. ochrolaemus lineages may have been hampered by the previous existence of well established A. infuscatus lineages in the region.

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Based on a cladistic biogeographic analysis of 6 species-level phylogenies of harvestman taxa, we searched for congruence in the historical relationships of 12 areas of endemism of the Brazilian Atlantic Rain Forest. We constructed general area cladograms using Primary Brooks Parsimony Analysis (BPA), BPA of nodes, and paralogy-free subtree analysis. These analyses resulted in 6 general area cladograms, that allow to infer a general pattern of the relationships among areas of endemism from the Brazilian Atlantic Rain Forest. Northern areas resulted related basally showing main disjunctions at the Doce River Valley and Todos os Santos Bay/São Francisco River Valley. The remaining areas of endemism were included in a southern and a southeastern block, separated by the Ribeira do Iguape Valley. Incongruence Length Differences tests showed no significant incongruence among the resulting cladograms and other matrix partitions. We concluded that tectonism and ancient marine transgressions were the probable processes responsible for the main disjunctions, whereas Neogene refugia seem to have caused the more recent disjunctions. The general pattern and redundancy in area relationships suggest a model of main reiterative barriers in diversification at multiple times for the evolution of the Atlantic Rain Forest. The renewal of cladistic biogeography and the search for common biogeographic patterns are discussed.