Comprehensive Phylogenetic Hypothesis Research Articles

Systematics and biogeography of a Sunda-Papuan snake lineage (Natricidae: Tropidonophis Jan 1863)

Abstract Sunda-Papuan keelback snakes (Serpentes: Natricidae: Tropidonophis Jan 1863) include 20 species distributed from the Philippines south-east through the Moluccas to New Guinea and Australia. Diversity of this insular snake lineage peaks on the island of New Guinea. Previous phylogenetic studies incorporating Tropidonophis have been limited to multi-locus Sanger-sequenced datasets with broad squamate or family-level focus. We used a targeted-sequence capture approach to sequence thousands of nuclear ultraconserved elements (UCEs) to construct the most comprehensive sequence-based phylogenetic hypothesis for this genus and estimate ancestral biogeography. Phylogenies indicate the genus is monophyletic given recent taxonomic reassignment of Rhabdophis spilogaster to Tropidonophis. All UCE phylogenies recovered a monophyletic Tropidonophis with reciprocally monophyletic Philippine and New Guinean clades. Divergence dating and ancestral range estimation suggest dispersal to New Guinea from the Philippines to have occurred during the Mid-Miocene via the Oceanic Arc Terranes. From Late Miocene into the Pliocene the genus experienced rapid diversification from orogeny of the New Guinean Central Cordillera from Oceanic Arc Terrane accretion on the northern boundary of the Sahul Shelf. Future collecting of missing taxa from the Moluccas and Indonesian Papua will better the understanding of non-volant faunal biogeography and diversification in this tectonically complex Pacific arena.

Phylogenomics, evolution of trophic traits and divergence times of hemiodontid fishes (Ostariophysi: Characiformes)

The South American characiform family Hemiodontidae comprises five genera and 34 species. The family lacks comprehensive phylogenetic hypotheses resolving its species relationships. The studies that addressed these questions exhibited a narrow taxon sampling or used single-locus markers. Herein we surveyed hundreds of ultraconserved elements (UCEs) loci to provide the first molecular phylogenetic hypothesis and divergence time estimates for hemiodontids encompassing all its genera and most species (27 of the 34 valid species). We also tracked the history of the protractile upper jaw in the genera Argonectes and Bivibranchia across the recovered phylogenies through ancestral state reconstruction. Our results corroborate the monophyly of Hemiodontidae and the genera Argonectes and Bivibranchia in all phylogenetic methods with maximum clade support. The genera Anodus and Hemiodus were not monophyletic because Anodus elongatus was sister to the monotypic Micromischodus instead of A. orinocensis, and H. immaculatus did not form a clade with its other congeners, but instead was sister to the clade including Anodus and Micromischodus. All remaining species of Hemiodus were placed together into a monophyletic group, where they were arranged into four major subclades. The relationship in the family is summarised as: (Bivibranchia, (Argonectes, ((H. immaculatus, (Anodus, Micromischodus)), Hemiodus clade))), in discordance with the morphological phylogeny that placed all genera monophyletic and resolved the family as: ((Anodus, Micromischodus), (Hemiodus, (Argonectes, Bivibranchia))). The origin of Hemiodontidae was estimated from the Late Cretaceous to the Middle Paleogene, with the mean age in the Paleocene, while the origin of most hemiodontid genera except Bivibranchia occurred in the Miocene. Unordered parsimony and likelihood reconstruction indicates that Argonectes and Bivibranchia developed their protractile upper jaw independently.

Phylogenomics of the Caribbean melocacti: Cryptic species and multiple invasions

AbstractThe widespread Neotropical genus Melocactus of approximately 42 currently recognized species, is most diverse in eastern Brazil and the Greater Antilles, especially Cuba. Species delimitation is notoriously problematic in the group, although this is due in part to a lack of detailed systematic studies, as well as a severely cluttered nomenclatural history. To date, no comprehensive phylogenetic hypotheses have been generated for the clade, although some population genetic and morphological studies exist. We generated the largest phylogenetic dataset of Melocactus to date based on plastome data derived from a genome‐skimming approach for 26 taxa, which provided a framework for understanding species limits and relationships among Caribbean species. Our time‐calibrated phylogeny revealed a mid‐Pleistocene origin for Melocactus, and we resolved three major clades, a Cuban clade, a mostly South American clade, and a widespread Caribbean clade, which also included some South American taxa. Our topology recovered the Cuban clade as sister to the rest of the species, although this placement was poorly supported, and several other Cuban species are scattered throughout the rest of the tree. Biogeographic analyses suggested multiple dispersal events from South America leading to the current diversity on Cuba, as well as other parts of the Antilles. Based on our phylogenetic results, previous hypotheses of species numbers and relationships in the Caribbean generated solely on morphology have, in some cases, been greatly underestimated. Our study shows that plastome data are effective for resolving clades and species limits in Melocactus, although future work will need to include broader sampling and larger datasets to fully resolve relationships in this complicated group of cacti. We describe one new cryptic species for Cuba, Melocactus santiagoensis sp. nov., and provide a new combination (Melocactus lagunaensis comb. & stat. nov.), based on our phylogenetic results and morphological data and typify numerous names in the genus. The genus Melocactus is another striking example of the exceptional diversity that has been generated in the poorly studied, seasonally dry tropical forest of the Greater Antilles.

What is adaptive radiation? Many manifestations of the phenomenon in an iconic lineage of Hawaiian spiders

Adaptive radiation provides the ideal context for identifying and testing the processes that drive evolutionary diversification. However, different adaptive radiations show a variety of different patterns, making it difficult to come up with universal rules that characterize all such systems. Diversification may occur via several mechanisms including non-adaptive divergence, adaptation to novel environments, or character displacement driven by competition. Here, we characterize the ways these different drivers contribute to present-day diversity patterns, using the exemplary adaptive radiation of Hawaiian long-jawed orbweaver (Tetragnatha) spiders. We present the most taxonomically comprehensive phylogenetic hypothesis to date for this group, using 10 molecular markers and representatives from every known species across the archipelago. Among the lineages that make up this remarkable radiation, we find evidence for multiple diversification modalities. Several clades appear to have diversified in allopatry under a narrow range of ecological conditions, highlighting the role of niche conservatism in speciation. Others have shifted into new environments and evolved traits that appear to be adaptive in those environments. Still others show evidence for character displacement by close relatives, often resulting in convergent evolution of stereotyped ecomorphs. All of the above mechanisms seem to have played a role in giving rise to the exceptional diversity of morphological, ecological and behavioral traits represented among the many species of Hawaiian Tetragnatha. Taking all these processes into account, and testing how they operate in different systems, may allow us to identify universal principles underlying adaptive radiation.

Phylogeny and biogeography of the ancient spider family Filistatidae (Araneae) is consistent both with long-distance dispersal and vicariance following continental drift.

Filistatids, the crevice weavers, are an ancient family of cribellate spiders without extant close relatives. As one of the first lineages of araneomorph spiders, they present a complicated mixture of primitive and derived characters that make them a key taxon to elucidate the phylogeny of spiders, as well as the evolution of phenotypic characters in this group. Their moderate diversity (187 species in 19 genera) is distributed mainly in arid and semi-arid subtropical zones of all continents, except Antarctica. The objective of this paper is to generate a comprehensive phylogenetic hypothesis for this family to advance the understanding of its morphological evolution and biogeography, as well as lay the basis for a natural classification scheme. By studying the morphology using optical and electronic microscopy techniques, we produced a matrix of 302 morphological characters coded for a sample of 103 species of filistatids chosen to represent the phylogenetic diversity of the family. In addition, we included sequences of four molecular markers (COI, 16S, H3 and 28S; 3787 aligned positions) of 70 filistatid species. The analysis of the data (morphological, molecular, and combined) consistently indicates the separation of the Filistatidae into two subfamilies, Prithinae and Filistatinae, in addition to supporting several groups of genera: Filistata, Zaitunia and an undescribed genus from Madagascar; Sahastata and Kukulcania; all Prithinae except Filistatinella and Microfilistata; Antilloides and Filistatoides; a large Old World group including Pritha, Tricalamus, Afrofilistata, Labahitha, Yardiella, Wandella and putative new genera; and a South American group formed by Lihuelistata, Pikelinia and Misionella. Pholcoides is transferred to Filistatinae and Microfilistata is transferred to Prithinae, and each represents the sister group to the remaining genera of its own subfamily. Most genera are valid, although Pikelinia is paraphyletic with respect to Misionella, so we consider the two genera as synonyms and propose a few new generic combinations. Considering the new phylogenetic hypothesis, we discuss the evolution of some morphological character systems and the biogeography of the family. The ages of divergence between clades were estimated using a total-evidence tip-dating approach by including fossils of Filistatidae and early spider clades; this approach resulted in younger age estimates than those obtained with traditional node-dating. Filistatidae is an ancient family that started diversifying in the Mesozoic and most genera date to the Cretaceous. Clades displaying transcontinental distributions were most likely affected by continental drift, but at least one clade shows unequivocal signs of transoceanic long-distance dispersal.

Phylogenomics and host-switching patterns of Philopteridae (Psocodea: Phthiraptera) feather lice

Philopteridae feather lice are a group of ectoparasitic insects which have intimate relationships with their avian hosts. Feather lice include an enormous number of described species; however, the relationships of major lineages have been clouded by homoplasious characters due to convergent evolution. In this study, a comprehensive phylogenomic analysis of the group is performed which includes 137 feather louse species. Several other analyses are also completed including dating analysis, cophylogenetic reconstructions, and ancestral character estimation to understand the evolution of complex morphological and ecological traits. Phylogenetic results recover high support for the placement of major feather louse lineages, but with lower support for long-branched enigmatic genera found at the base of the tree. The results of dating analyses suggest modern feather lice began to diversify approximately 49 million years ago following the adaptive radiation of their avian hosts. Cost-based cophylogenetic reconstructions recover a high frequency of host switching, while congruence-based methods indicate a significant level of congruence between host and parasite trees. Ancestral state reconstructions favour a generalist ancestor and water bird host at the root. The analyses completed provide insight into the evolution of a diverse group of ectoparasitic insects which infest a wide variety of avian hosts. The results represent the most comprehensive phylogenetic hypothesis of the group to date and provide a framework for future classification of the family into natural groupings.

FishPhyloMaker: An R package to generate phylogenies for ray-finned fishes

Phylogenies summarize evolutionary information that is essential in the investigation of ecological and evolutionary causes of diversity patterns. They allow investigating hypotheses from trait evolution to the relationship between evolutionary diversity and ecosystem functioning. However, obtaining a comprehensive phylogenetic hypothesis can be difficult for some groups, especially those with a high number of species, that is the case for fishes, particularly tropical ones. The lack of species in phylogenetic hypotheses, called Darwinian shortfalls, can hinder ecological and evolutionary studies involving this group. To tackle this problem, we developed FishPhyloMaker, an R package that facilitates the generation of phylogenetic trees through a reliable and reproducible procedure, even for a large number of species. The package adopts well-known rules of insertion based on cladistic hierarchy, allowing its use by specialists and non-specialists in fish systematics. We tested the reliability of our algorithm in maintaining important properties of phylogenetic distances running a sensitivity analysis. We also exemplified the use of the FishPhyloMaker package by constructing complete phylogenies for fishes inhabiting the four richest freshwater ecoregions of the world. Furthermore, we proposed a new method to calculate Darwinian shortfalls and mapped this information for the major freshwater drainages of the world. FishPhyloMaker will expand the range of evolutionary and ecological questions that can be addressed using ray-finned fishes as study models, mainly in the field of community phylogenetics, by providing an easy and reliable way to obtain comprehensive phylogenies. Further, FishPhyloMaker presents the potential to be extended to other taxonomic groups that suffer from the same difficulty in the obtention of comprehensive phylogenetic hypothesis.

Combining genomic, phenotypic and Sanger sequencing data to elucidate the phylogeny of the two-clawed spiders (Dionycha)

The importance of morphology in the phylogenomic era has recently gained attention, but relatively few studies have combined both types of information when inferring phylogenetic relationships. Sanger sequencing legacy data can also be important for understanding evolutionary relationships. The possibility of combining genomic, morphological and Sanger data in one analysis seems compelling, permitting a more complete sampling and yielding a comprehensive view of the evolution of a group. Here we used these three data types to elucidate the systematics and evolution of the Dionycha, a highly diverse group of spiders relatively underrepresented in phylogenetic studies. The datasets were analyzed separately and combined under different inference methods, including a novel approach for analyzing morphological matrices with commonly used evolutionary models. We tested alternative hypotheses of relationships and performed simulations to investigate the accuracy of our findings. We provide a comprehensive and thorough phylogenetic hypothesis for Dionycha that can serve as a robust framework to test hypotheses about the evolution of key characters. We also show that morphological data might have a phylogenetic impact, even when massively outweighed by molecular data. Our approach to analyze morphological data may serve as an alternative to the proposed practice of arbitrarily partitioning, weighting, and choosing between parsimony and stochastic models. As a result of our findings, we propose Trachycosmidae new rank for a group of Australian genera formerly included in Trochanteriidae and Gallieniellidae, and consider Ammoxenidae as a junior synonym of Gnaphosidae. We restore the family rank for Prodidomidae, but transfer the subfamily Molycriinae to Gnaphosidae. Drassinella is transferred to Liocranidae, Donuea to Corinnidae, and Mahafalytenus to Viridasiidae.

A nuclear phylogenomic study of the angiosperm order Myrtales, exploring the potential and limitations of the universal Angiosperms353 probe set.

To further advance the understanding of the species-rich, economically and ecologically important angiosperm order Myrtales in the rosid clade, comprising nine families, approximately 400 genera and almost 14,000 species occurring on all continents (except Antarctica), we tested the Angiosperms353 probe kit. We combined high-throughput sequencing and target enrichment with the Angiosperms353 probe kit to evaluate a sample of 485 species across 305 genera (76% of all genera in the order). Results provide the most comprehensive phylogenetic hypothesis for the order to date. Relationships at all ranks, such as the relationship of the early-diverging families, often reflect previous studies, but gene conflict is evident, and relationships previously found to be uncertain often remain so. Technical considerations for processing HTS data are also discussed. High-throughput sequencing and the Angiosperms353 probe kit are powerful tools for phylogenomic analysis, but better understanding of the genetic data available is required to identify genes and gene trees that account for likely incomplete lineage sorting and/or hybridization events.

Evolution of the strikingly diverse submandibular muscles in Anura.

The most ventral muscles of the head (the mm. submentalis, intermandibularis, and interhyoideus) provide support to the gular region and lift the buccal floor during ventilation and feeding. These muscles show limited variation in most gnathostomes, but in Anura they exhibit a surprising diversity. The few studies that have explored this character system highlighted its potential as a source of phylogenetic information. In this paper we explored the diversity of this character system studying specimens of 567 anuran species and reviewing published data to cover a total of 1321 species, belonging to 53 of the 54 currently recognized anuran families, as well as caudates and caecilians. We defined 27 discrete characters including the number of muscle bellies, supplementary layers, hypertrophy and diversity of elastic fibres, and pigmentation, among others, and optimized them on a comprehensive phylogenetic hypothesis. We recognized 223 unambiguously optimized synapomorphies for numerous clades on different scales, including three for Anura and many for suprafamiliar clades with poor phenotypic support. Finally, we discussed the evolution of this highly diverse character system, including homology, development, and its functional role in vocalization and feeding. Interestingly, the striking levels of variation in some structures contrast with the amount of phylogenetic inertia, allowing us to recognize several general patterns. Supplementary elements of the m. intermandibularis evolved first as broad layers occuring in more than half of extant anuran species and then concentrated forming discreet bellies in several clades. The anterior portion of the gular region is not sexually dimorphic, and is likely related to ventilation and tongue protraction. Conversely, the diversity of the m. interhyoideus is strongly linked to vocal sacs, which are present only in adult males, suggesting the presence of two independent modules.

The phylogenetics of Teleosauroidea (Crocodylomorpha, Thalattosuchia) and implications for their ecology and evolution.

Teleosauroidea was a clade of ancient crocodylomorphs that were a key element of coastal marine environments during the Jurassic. Despite a 300-year research history and a recent renaissance in the study of their morphology and taxonomy, macroevolutionary studies of teleosauroids are currently limited by our poor understanding of their phylogenetic interrelationships. One major problem is the genus Steneosaurus, a wastebasket taxon recovered as paraphyletic or polyphyletic in phylogenetic analyses. We constructed a newly updated phylogenetic data matrix containing 153 taxa (27 teleosauroids, eight of which were newly added) and 502 characters, which we analysed under maximum parsimony using TNT 1.5 (weighted and unweighted analyses) and Bayesian inference using MrBayes v3.2.6 (standard, gamma and variation). The resulting topologies were then analysed to generate comprehensive higher-level phylogenetic hypotheses of teleosauroids and shed light on species-level interrelationships within the clade. The results from our parsimony and Bayesian analyses are largely consistent. Two large subclades within Teleosauroidea are recovered, and they are morphologically, ecologically and biogeographically distinct from one another. Based on comparative anatomical and phylogenetic results, we propose the following major taxonomic revisions to Teleosauroidea: (1) redefining Teleosauridae; (2) introducing one new family and three new subfamilies; (3) the resurrection of three historical genera; and (4) erecting seven new generic names and one new species name. The phylogeny infers that the Laurasian subclade was more phenotypically plastic overall than the Sub-Boreal-Gondwanan subclade. The proposed phylogeny shows that teleosauroids were more diverse than previously thought, in terms of morphology, ecology, dispersal and abundance, and that they represented some of the most successful crocodylomorphs during the Jurassic.

A novel phylogenetic infrageneric classification of Baccharis (Asteraceae: Astereae), a highly diversified American genus

AbstractWe present the hitherto most comprehensive phylogenetic hypothesis for Baccharis. Our results confirm that subtribe Baccharidinae is a monogeneric group and support a broad circumscription of Baccharis as monophyletic with the inclusion of all genera that have been previously segregated from it (Baccharidastrum, Baccharidiopsis, Heterothalamulopsis, Heterothalamus, Lanugothamnus). We provide comprehensive lists of accepted and synonymized infrageneric taxa. Seven main lineages are recognized, which we treat as subgenera. Subgenera Baccharis and Molina roughly match previous circumscriptions, while subgenera Pteronioides and Stephananthus are merged with Molina. In total, we propose that Baccharis comprises 440 species classified into 7 subgenera and 47 sections, while 22 sections are considered synonyms. The phylogeny provided constitutes the basis for further exploration of the evolutionary processes that have allowed the group to attain its wide geographic distribution, morphological variation, variable sexual reproductive strategies, and complex chemical contents.

On the ancestry of woodrats

Abstract We evaluated the fossil record of extinct and extant woodrats, and generated a comprehensive phylogenetic hypothesis of woodrat origins and relationships based on these data. The galushamyinin cricetines are redefined and reclassified as a subtribe of the Neotomini, including Repomys, Miotomodon, Galushamys, Nelsonia, and a new extinct genus with two new species. The geographic distribution of Nelsonia, restricted to montane coniferous forests of western Mexico, suggests that this subtribe was mostly confined to western coniferous ecosystems or similar ecosystems at lower elevation during glacial advances. A second subtribe of the Neotomini includes a new archaic genus and species, Neotoma, Hodomys, and Xenomys. Lindsaymys, a possible neotominin from the late Clarendonian (late Miocene) of California, demonstrates an occlusal morphology consistent with ancestry for the Neotomini, but the presence of a fourth root on M1 is problematic and may preclude the known populations from filling that role. Molars identified as Neotoma sp. from the Hemphillian (latest Miocene or early Pliocene) Rancho el Ocote assemblage of Guanajuato, Mexico, may represent the earliest Xenomys. Extant Neotoma species with a bilobed m3 appear to have originated subsequent to about 2.0 Ma, whereas Hodomys alleni and Xenomys nelsoni likely originated earlier from one or more extinct ancestors with an S-shaped m3.

Earth history and the passerine superradiation

Avian diversification has been influenced by global climate change, plate tectonic movements, and mass extinction events. However, the impact of these factors on the diversification of the hyperdiverse perching birds (passerines) is unclear because family level relationships are unresolved and the timing of splitting events among lineages is uncertain. We analyzed DNA data from 4,060 nuclear loci and 137 passerine families using concatenation and coalescent approaches to infer a comprehensive phylogenetic hypothesis that clarifies relationships among all passerine families. Then, we calibrated this phylogeny using 13 fossils to examine the effects of different events in Earth history on the timing and rate of passerine diversification. Our analyses reconcile passerine diversification with the fossil and geological records; suggest that passerines originated on the Australian landmass ∼47 Ma; and show that subsequent dispersal and diversification of passerines was affected by a number of climatological and geological events, such as Oligocene glaciation and inundation of the New Zealand landmass. Although passerine diversification rates fluctuated throughout the Cenozoic, we find no link between the rate of passerine diversification and Cenozoic global temperature, and our analyses show that the increases in passerine diversification rate we observe are disconnected from the colonization of new continents. Taken together, these results suggest more complex mechanisms than temperature change or ecological opportunity have controlled macroscale patterns of passerine speciation.

Phylogeny and molecular species delimitation of long-nosed armadillos (Dasypus: Cingulata) supports morphology-based taxonomy

AbstractThe armadillo genus Dasypus is the most species-rich and widely distributed genus of the order Cingulata and it has a dynamic taxonomic history. Recent morphology-based studies have proposed new taxonomic arrangements, but these were not yet assessed with molecular data. The two comprehensive phylogenetic hypotheses available for the genus are conflicting and were each based on a subset of taxa, hampering a proper evaluation of species boundaries. Using a multilocus molecular dataset, based on the broadest geographic sampling of Dasypus to date, we inferred the phylogenetic relationships of all species of the genus, including the recently reinstated D. beniensis and D. pastasae. We tested recent taxonomic hypotheses using several species-delimitation approaches. Our phylogeny recovered three main lineages of long-nosed armadillos that we treat as subgenera (Hyperoambon, Muletia and Dasypus) and identified the majority of its diversification as having occurred during the Pliocene. Molecular species delimitation supported morphological evidence in assigning D. hybridus as a subspecies of D. septemcinctus and confirming the split of the D. kappleri complex into three species. Our results strongly support the recognition of Guiana Shield populations formerly assigned to D. novemcinctus as a distinct species. The phylogenetic positions of D. mazzai and D. sabanicola remain uncertain. Further investigation using faster-evolving genes and additional samples may help to clarify the relationships of these young species.

Integration of phylogenomics and molecular modeling reveals lineage-specific diversification of toxins in scorpions.

Scorpions have evolved a variety of toxins with a plethora of biological targets, but characterizing their evolution has been limited by the lack of a comprehensive phylogenetic hypothesis of scorpion relationships grounded in modern, genome-scale datasets. Disagreements over scorpion higher-level systematics have also incurred challenges to previous interpretations of venom families as ancestral or derived. To redress these gaps, we assessed the phylogenomic relationships of scorpions using the most comprehensive taxonomic sampling to date. We surveyed genomic resources for the incidence of calcins (a type of calcium channel toxin), which were previously known only from 16 scorpion species. Here, we show that calcins are diverse, but phylogenetically restricted only to parvorder Iurida, one of the two basal branches of scorpions. The other branch of scorpions, Buthida, bear the related LKTx toxins (absent in Iurida), but lack calcins entirely. Analysis of sequences and molecular models demonstrates remarkable phylogenetic inertia within both calcins and LKTx genes. These results provide the first synapomorphies (shared derived traits) for the recently redefined clades Buthida and Iurida, constituting the only known case of such traits defined from the morphology of molecules.

Phylogeny of some Devonian trilobites and consequences for the systematics of Austerops (Phacopidae)

A comprehensive phylogenetic hypothesis for Devonian phacopid trilobites of the genus Austerops has not previously been proposed. We carried out a cladistic analysis of the 13 species and subspecies assigned to Austerops, based on a data matrix of 63 characters. Two species of the morphologically very similar genus Chotecops, C. auspex and C. hoseri, and seven other close relatives (Reedops cephalotes hamlagdadianus, Boeckops stelcki, Morocops granulops, Paciphacops logani, Phacops latifrons, Phacops araw and Pedinopariops (Hypsipariops) vagabundus) were also included in the analysis in order to test their relationship with species of Austerops. Parsimony analyses using a heuristic method, with Calyptaulax callirachis and C. glabella as outgroup taxa, produced two most parsimonious trees of 341 steps. These trees are partly consistent with trees obtained from additional analyses performed with modified data sets (deletion of homoplastic characters, multistate characters, continuous characters carved into 5% increments, thoracic and pygidial characters, or taxa with numerous unknown characters). Results suggest that Austerops sp. B and A.? sp. D are close to Chotecops hoseri and C. auspex, and that these species constitute a monophyletic group. Austerops Austerops menchikoffi, A. speculator and A. punctatus are also a monophyletic group and reasonably constitute a sister group of that formed by the rest of Austerops and Chotecops sensu lato, while A. hottonensis seems phylogenetically distant from other representatives of Austerops. Chotecops including C. hoseri and C. auspex together with Austerops sp. B and A.? sp. D seem derived from A. legrandi. The relationship between Austerops and Chotecops remains partly unresolved but it seems likely that their recognition as separate taxa results in paraphyletic groups. The phylogenetic analysis suggests that the currently poorly known Austerops sp. B and A.? sp. D should be reassigned to Chotecops.

Recurrent diversification patterns and taxonomic complexity in morphologically conservative ancient lineages of Pimelia (Coleoptera: Tenebrionidae)

AbstractThe genus Pimelia Fabricius is the most speciose in the tribe Pimeliini (Coleoptera: Tenebrionidae). It consists of approximately 320 species distributed mainly in xeric environments in the western Palaearctic region and northern deserts in the Afrotropical region. Pimelia is a very heterogenous group despite its conserved morphology. Based on two mitochondrial (cox1 and 16S) and five nuclear markers (ITS1, ITS2, 18S, Wg and H3), we carried out a phylogenetic and biogeographic study to: (i) provide a comprehensive phylogenetic hypothesis for the relationships within Pimelia; (ii) re‐evaluate the taxonomic status and organization of clades (subgenera) within the genus; and (iii) establish a temporal framework and historical scenario for the evolution and diversification of Pimelia in the western Mediterranean Region. Pimelia presents a high degree of morphological conservatism and possibly stasis, often resulting in complexes of cryptic species. Repetitive patterns of variation are found recurrently between and within groups, which resulted in a conundrum of nonmonophyletic taxonomic assemblages based on morphological homoplastic characters. Based on our results, we propose a new taxonomic arrangement for Pimelia with 14 clades, treated as subgenera, with the description of six new subgenera: Iberomelia subgen.n., Italomelia subgen.n., Magrebmelia subgen.n., Hispanomelia subgen.n., Massadraamelia subgen.n. and Amblypteraca subgen.n. Our results also indicate an Oligocene (Rupelian) origin for Pimelia, and North Africa as the most likely area of origin. The complex geological and climatic history in the western Mediterranean region has shaped the distribution and diversity of species in the area. The current faunal assemblages observed in Pimelia are the result of complex patterns of recurrent processes of dispersal and vicariance, including in situ diversification through time in different areas of the Mediterranean basin. Pimelia is a fascinating yet very challenging group, and the phylogenetic and systematic framework developed here will pave the way for further ecological, taxonomic, and evolutionary studies at local and regional scales.This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:DCA003F7‐85F4‐4803‐A859‐5738C6473151.

Loss of metagenesis and evolution of a parasitic life style in a group of open-ocean jellyfish

Loss or stark reduction of the free-swimming medusa or jellyfish stage is common in the cnidarian class Hydrozoa. In the hydrozoan clade Trachylina, however, many species do not possess a sessile polyp or hydroid stage. Trachylines inhabiting freshwater and coastal ecosystems (i.e., Limnomedusae) possess a metagenetic life cycle involving benthic, sessile polyp and free-swimming medusa. In contrast, the paradigm is that open ocean inhabiting, oceanic trachylines (in the orders Narcomedusae and Trachymedusae) develop from zygote to medusa via a free-swimming larva, forgoing the polyp stage. In some open-ocean trachylines, development includes a sessile stage that is an ecto- or endoparasite of other oceanic organisms. We expand the molecular-based phylogenetic hypothesis of trachylines significantly, increasing taxon and molecular marker sampling. Using this comprehensive phylogenetic hypothesis in conjunction with character state reconstructions we enhance understanding of the evolution of life cycles in trachyline hydrozoans. We find that the polyp stage was lost at least twice independently, concurrent with a transition to an oceanic life style. Further, a sessile, polypoid parasitic stage arose once, rather than twice as current classification would imply, in the open ocean inhabiting Narcomedusae. Our results also support the hypothesis that interstitial species of the order Actinulida are directly descended from direct developing, oceanic trachylines.

An ant genus-group (Prenolepis) illuminates the biogeography and drivers of insect diversification in the Indo-Pacific

The Malay Archipelago and the tropical South Pacific (hereafter the Indo-Pacific region) are considered biodiversity hotspots, yet a general understanding of the origins and diversification of species-rich groups in the region remains elusive. We aimed to test hypotheses for the evolutionary processes driving insect species diversity in the Indo-Pacific using a higher-level and comprehensive phylogenetic hypothesis for an ant clade consisting of seven genera. We estimated divergence times and reconstructed the biogeographical history of ant species in the Prenolepis genus-group (Formicidae: Formicinae: Lasiini). We used a fossil-calibrated phylogeny to infer ancestral geographical ranges utilizing a biogeographic model that includes founder-event speciation. Ancestral state reconstructions of the ants' ecological preferences, and diversification rates were estimated for selected Indo-Pacific clades. Overall, we report that faunal interchange between Asia and Australia has occurred since at least 20–25 Ma, and early dispersal to the Fijian Basin happened during the early and mid-Miocene (ca. 10–20 Ma). Differences in diversification rates across Indo-Pacific clades may be related to ecological preference breadth, which in turn may have facilitated geographical range expansions. Ancient dispersal routes suggested by our results agree with the palaeogeography of the region. For this particular group of ants, the rapid orogenesis in New Guinea and possibly subsequent ecological shifts may have promoted their rapid diversification and widespread distribution across the Indo-Pacific.