UPDATING THE GENUS DICTYOSPHAERIUM AND DESCRIPTION OF MUCIDOSPHAERIUM GEN. NOV. (TREBOUXIOPHYCEAE) BASED ON MORPHOLOGICAL AND MOLECULAR DATA1

Recent molecular analyses of Dictyosphaerium strains revealed a polyphyletic origin of this morphotype within the Chlorellaceae. The type species Dictyosphaerium ehrenbergianum Nägeli formed an independent lineage within the Parachlorella clade, assigning the genus to this clade. Our study focused on three different Dictyosphaerium species to resolve the phylogenetic position of remaining species. We used combined analyses of morphology; molecular data based on SSU and internally transcribed spacer region (ITS) rRNA sequences; and the comparison of the secondary structure of the SSU, ITS‐1, and ITS‐2 for species and generic delineation. The phylogenetic analyses revealed two lineages without generic assignment and two distinct clades of Dictyosphaerium‐like strains within the Parachlorella clade. One clade comprises the lineages with the epitype strain of D. ehrenbergianum Nägeli and two additional lineages that are described as new species (Dictyosphaerium libertatis sp. nov. and Dictyosphaerium lacustre sp. nov.). An emendation of the genus Dictyosphaerium is proposed. The second clade comprises the species Dictyosphaerium sphagnale Hindák and Dictyosphaerium pulchellum H. C. Wood. On the basis of phylogenetic analyses, complementary base changes, and morphology, we describe Mucidosphaerium gen. nov with the four species Mucidosphaerium sphagnale comb. nov., Mucidosphaerium pulchellum comb. nov., Mucidosphaerium palustre sp. nov., and Mucidosphaerium planctonicum sp. nov.     

Phylogeny of the green lacewing Chrysoperla nipponensis species‐complex (Neuroptera: Chrysopidae) in China,based on mitochondrial sequences and AFLP data

Abstract Several studies have indicated that the green lacewing, Chrysoperla nipponensis (Neuroptera: Chrysopidae) may include more than one valid species. We investigated the phylogenetic status of Chrysoperla nipponensis s.l. in China and Japan using mitochondrial sequences and AFLP data. The molecular phylogenetic analyses based on mitochondrial genes showed that the C. nipponensis species‐complex comprises four clades, each having high support values. In addition, the phylogenetic tree based on AFLP data indicates that the species‐complex comprises three groups. These results confirm that C. nipponensis s.l. comprises at least three genetically distinct clades and suggests that two of these clades may be closely related to populations of C. nipponensis in Japan. However, these clades cannot be recognized as species until analysis of their courtship songs has been completed.     

Molecular phylogeny and morphological analysis resolve a long‐standing controversy over generic concepts in Ecdyonurinae mayflies (Ephemeroptera: Heptageniidae)

Heptageniidae is a species‐rich mayfly family (Ephemeroptera), whose taxonomy and phylogeny have been based almost exclusively on traditional morphological studies. Inconsistent use of diagnostic characters and the general lack of molecular studies have led to vague generic concepts, and the phylogenetic relationships among taxa in the family remain unclear. Afronurus Lestage is an Old World heptageniid genus of 66 species. The generic assignment of two species within this genus, A. kugleri Demoulin and A. zebratus (Hagen), has been the subject of much debate, because they share many apomorphic features that distinguish them from other congeners. We combined a thorough morphological study of all life stages of 28 representative heptageniid species with a molecular phylogenetic analysis of four mitochondrial and nuclear markers to resolve the generic position of A. kugleri and A. zebratus as well as the integrity of Afronurus and related genera. Our results confirm the monophyly of Afronurus and Electrogena and support the assignment of A. kugleri and A. zebratus to a newly described genus, Anapos Yanai & Sartori gen.n . We provide clear, diagnostic morphological characters for the genus and discuss the need for a thorough revision of generic concepts in the subfamily Ecdyonurinae. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:075E40C6-BAFE-4184-A2C2-E3BCFBC0BC15 .     

Phylogeny, biogeography and evolution of clutch size in South American lizards of the genus Kentropyx (Squamata: Teiidae)

The lizard genus Kentropyx (Squamata: Teiidae) comprises nine species, which have been placed in three species groups (calcarata group, associated to forests ecosystems; paulensis and striata groups, associated to open ecosystems). We reconstructed phylogenetic relationships of Kentropyx based on morphology (pholidosis and coloration) and mitochondrial DNA data (12S and 16S), using maximum parsimony and Bayesian methods, and evaluated biogeographic scenarios based on ancestral areas analyses and molecular dating by Bayesian methods. Additionally, we tested the life‐history hypothesis that species of Kentropyx inhabiting open ecosystems (under seasonal environments) produce larger clutches with smaller eggs and that species inhabiting forest ecosystems (under aseasonal conditions) produce clutches with fewer and larger eggs, using Stearns’ phylogenetic‐subtraction method and canonical phylogenetic ordination to take in to account the effects of phylogeny. Our results showed that Kentropyx comprises three monophyletic groups, with K. striata occupying a basal position in opposition to previous suggestions of relationships. Additionally, Bayesian analysis of divergence time showed that Kentropyx may have originated at the Tertiary (Eocene/Oligocene) and the ‘Pleistocene Refuge Hypothesis’ may not explain the species diversification. Based on ancestral reconstruction and molecular dating, we argued that a savanna ancestor is more likely and that historical events during the Tertiary of South America promoted the differentiation of the genus, coupled with recent Quaternary events that were important as dispersion routes and for the diversification at populational levels. Clutch size and egg volume were not significantly different between major clades and ecosystems of occurrence, even accounting for the phylogenetic effects. Finally, we argue that phylogenetic constraints and phylogenetic inertia might be playing essential roles in life history evolution of Kentropyx.     

Nucleotide based validation of Ocimum species by evaluating three candidate barcodes of the chloroplast region

The genus Ocimum comprises of several medicinally important species which frequently fall prey to adulteration due to misidentification. A proficient method is hence required to solve the problems that exist in differentiating its various morphotypes. In plants, candidate DNA barcodes of the chloroplast and nuclear regions have proved to be a great success in the validation of several plant families. Hence, this study involves the use of the molecular‐based DNA barcoding method to identify some of the most common and useful species of the genus Ocimum (Tulsi). Here, DNA amplification of three candidate barcodes of the chloroplast genome viz. matK, rbcL and psbA‐trnH was performed, to access their ability to produce high sequence variability. The discrimination among species was performed using the Kimura 2‐parameter and maximum composite likelihood methods. On analysing the sequence data, the psbA‐trnH region proved to be the most suitable candidate barcode and gave an overall variation of 7.3% at the interspecies level. A clear differentiation was found at the species level, showing a maximum distance of 0.264 between dissimilar species. Also, phylogenetic analysis led to the successful identification of hybrids, while it failed to do so at the variety level. Hence, it can be inferred that DNA barcoding is ideal for species‐level identification of the genus Ocimum.     

Phylogeny and phylogeography of the Lozekia–Kovacsia species group (Gastropoda: Hygromiidae)

The Lozekia–Kovacsia species group comprises three species of high conservation concern, Lozekia transsilvanica (Westerlund, 1876), Lozekia deubeli (M. Kimakowicz, 1890) and Kovacsia kovacsi ( Varga and L. Pintér, 1972 ), which occupy relatively small ranges in the Carpathian‐Pannonian region. Despite their conservation concern, the phylogeny and biogeographical history of these species have not been studied by molecular methods up to now. This study, based on mitochondrial cytochrome oxidase subunit I gene sequences, has two main objectives: (i) to infer the phylogenetic relationships within the group in order to test the latest morphology‐based system, proposed by Nordsieck [1993, Das System der paläarktischen Hygromiidae (Gastropoda: Stylommatophora: Helicoidea). Arch Molluskenkunde 122:1] and (ii) to reconstruct the distribution history of the three species. The monophyly and thus the systematic distinctness of the three species was confirmed, but our findings do not support the monophyly of the Lozekia genus and therefore contradict the current system of the species group. Genetic diversity was found to be much higher within L. deubeli than within the other two species, a possible explanation of this phenomenon is that L. transsilvanica and K. kovacsi are more recently evolved, younger species. Nested clade phylogeographycal analysis showed that the three species evolved by fragmentation events; probably L. deubeli and the ancestor of the other two species split first. At the intraspecific level, fragmentation events, as well as range expansion, played a significant role in the biogeographical history of this species group. As our findings are based on a single mitochondrial gene, we feel premature to propose changes in the generally accepted system and nomenclature. Further molecular phylogenetic analyses, also involving nuclear DNA sequences, should clarify if the evolutionary scenario suggested by our data is valid, and the three species can indeed be placed within the same genus, Lozekia.     

The phylogenetic systematics of blue‐tailed skinks (Plestiodon) and the family Scincidae

Blue‐tailed skinks (genus Plestiodon) are a common component of the terrestrial herpetofauna throughout their range in eastern Eurasia and North and Middle America. Plestiodon species are also frequent subjects of ecological and evolutionary research, yet a comprehensive, well‐supported phylogenetic framework does not yet exist for this genus. We construct a comprehensive molecular phylogeny of Plestiodon using Bayesian phylogenetic analyses of a nine‐locus data set comprising 8308 base pairs of DNA, sampled from 38 of the 43 species in the genus. We evaluate potential gene tree/species tree discordance by conducting phylogenetic analyses of the concatenated and individual locus data sets, as well as employing coalescent‐based methods. Specifically, we address the placement of Plestiodon within the evolutionary tree of Scincidae, as well as the phylogenetic relationships between Plestiodon species, and their taxonomy. Given our sampling of major Scincidae lineages, we also re‐evaluate ‘deep’ relationships within the family, with the goal of resolving relationships that have been ambiguous in recent molecular phylogenetic analyses. We infer strong support for several scincid relationships, including a major clade of ‘scincines’ and the inter‐relationships of major Mediterranean and southern African genera. Although we could not estimate the precise phylogenetic affinities of Plestiodon with statistically significant support, we nonetheless infer significant support for its inclusion in a large ‘scincine’ clade exclusive of Acontinae, Lygosominae, Brachymeles, and Ophiomorus. Plestiodon comprises three major geographically cohesive clades. One of these clades is composed of mostly large‐bodied species inhabiting northern Indochina, south‐eastern China (including Taiwan), and the southern Ryukyu Islands of Japan. The second clade comprises species inhabiting central China (including Taiwan) and the entire Japanese archipelago. The third clade exclusively inhabits North and Middle America and the island of Bermuda. A vast majority of interspecific relationships are strongly supported in the concatenated data analysis, but there is nonetheless significant conflict amongst the individual gene trees. Coalescent‐based gene tree/species tree analyses indicate that incongruence amongst the nuclear loci may severely obscure the phylogenetic inter‐relationships of the primarily small‐bodied Plestiodon species that inhabit the central Mexican highlands. These same analyses do support the sister relationship between Plestiodon marginatus Hallowell, 1861 and Plestiodon stimpsonii (Thompson, 1912), and differ with the mitochondrial DNA analysis that supports Plestiodon elegans (Boulenger, 1887) + P. stimpsonii. Finally, because the existing Plestiodon taxonomy is a poor representation of evolutionary relationships, we replace the existing supraspecific taxonomy with one congruent with our phylogenetic results. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 163–189.     

Molecular systematics of the Philippine forest skinks (Squamata: Scincidae: Sphenomorphus): testing morphological hypotheses of interspecific relationships

Skinks of the genus Sphenomorphus are the most diverse clade of squamates in the Philippine Archipelago. Morphological examination of these species has defined six phenotypic groups that are commonly used in characterizations of taxonomic hypotheses. We used a molecular phylogeny based on four mitochondrial and two nuclear genes to assess the group's biogeographical history in the archipelago and examine the phylogenetic validity of the currently recognized Philippine species groups. We re‐examined traditional characters used to define species groups and used multivariate statistics to quantitatively evaluate group structure in morphometric space. Clustering analyses of phenotypic similarity indicate that some (but not all) members of previously defined species groups are phenotypically most similar to other members of the same group. However, when species group membership was mapped on our partitioned Bayesian phylogenetic hypothesis, only one species group corresponds to a clade; all other species group arrangements are strongly rejected by our phylogeny. Our results demonstrate that (1) previously recognized species group relationships were misled by phenotypic convergence; (2) Sphenomorphus is widely paraphyletic; and (3) multiple lineages have independently invaded the Philippines. Based on this new perspective on the phylogenetic relationships of Philippine Sphenomorphus, we revise the archipelago's diverse assemblage of species at the generic level, and resurrect and/or expand four previously recognized genera, and describe two new genera to accommodate the diversity of Philippine skinks of the Sphenomorphus group. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 1217–1243.     

An interplay between forest and non‐forest South American avifaunas suggested by a phylogeny of lepidocolaptes woodcreepers (dendrocolaptinae)

Very few South American avian superspecies or species groups are composed of both forest and non‐forest taxa. The genus Lepidocolaptes comprises 8–9 species of woodcreepers, most of which are forest birds, but two species, L. angustirostris and L. souleyetii, inhabit open vegetations. Therefore, this genus should play an important role in the discussion about the relationships between forest and non‐forest South American avifaunas. Nucleotide sequences from two mitochondrial genes, cytochrome b and ND2, suggest that: (i) L. fuscus should be removed from the genus since its association with other members of this genus is poorly supported. This view has been pointed out also by morphological and behavioural data; (ii) the phylogenetic position of the open‐vegetation species within the Lepidocolaptes radiation indicate that the split between forest and non‐forest elements within this genus took place as recently as two million years ago. This result suggests that the evolutionary relationships between forest and non‐forest biotas in South America may have been more dynamic than previously thought.     

Molecular phylogenetic and divergence time estimation analyses of the sawfly subfamily Selandriinae (Hymenoptera: Tenthredinidae)

Selandriinae, a subfamily of family Tenthredinidae (Hymenoptera: Symphyta), comprises multiple tribes, each of which has a relationship with specific plant group. The host specificity of the Selandriinae taxa provides a good model to examine the coevolution between hosts and insects. However, few phylogenetic studies for the Selandriinae obscure the evolutionary scenario with their host‐plants. The present study is a molecular phylogenetic analysis of 19 selandriine species based on mitochondrial genes (12S: 461 sites, 16S: 262sites and COI: 495 sites) and nuclear genes (18S: 773 sites and 28S: 495 sites). The results suggested three of six studied tribes are genetically isolated. Moreover, estimation of the time of molecular divergence showed that the Selandriinae clearly diverged at the same time as their host‐plants (monocots and ferns). These results suggested that the Selandriinae species might have codiversified with their hosts.     

Molecular phylogeny of the genus Helix (Pulmonata: Helicidae)

The vast diversity of land snail forms is insufficiently understood even in seemingly familiar taxa. This holds for Helix Linnaeus, 1758, a genus with several common edible species which comprises the largest Western Palearctic snails. The taxonomy of this genus, which has a centre of diversity in the eastern Mediterranean, has recently undergone significant changes, in both the delimitation of the genus itself and its species‐level systematics. Here, we compare the lineage diversity of Helix, as revealed by two mitochondrial markers, with the conclusions of the recently published morphology‐based taxonomic revision. For the molecular analysis, we assembled a representative data set covering almost all species of the genus as recognized by the mentioned revision. We obtained sequences not only from fresh and preserved soft tissues but also from dried tissue remains (some of them decades old) from shell collections. Our results show that the genus Helix, in the narrow sense proposed by recent studies, is paraphyletic because the genus Tacheopsis was unambiguously revealed as one of the tip branches of Helix. The monophyly of several species, as presently recognized, was not supported; partly, this may be attributed to a lineage diversity overlooked so far. This holds also for the type species of the genus, H. pomatia, which comprises at least one additional lineage. Greece, the Aegean and western Turkey is the core area for the diversity of Helix and its relatives, and the region is probably a major long‐term refuge for large Helicidae. The highest species diversity is found along the Alpide belt from the western Balkans to southern Turkey. The diversity of Helix in Europe, north of Greece and the Apennines, is a result of a single European radiation. Our data also suggest that past human activities likely influenced the present‐day distributions of some species.     

Molecular systematics of flyingfishes (Teleostei: Exocoetidae): evolution in the epipelagic zone

The flyingfish family Exocoetidae is a diverse group of marine fishes that are widespread and abundant in tropical and subtropical seas. Flyingfishes are epipelagic specialists that are easily distinguished by their enlarged fins, which are used for gliding leaps over the surface of the water. Although phylogenetic hypotheses have been proposed for flyingfish genera based on morphology, no comprehensive molecular studies have been performed. In the present study, we describe a species‐level molecular phylogeny for the family Exocoetidae, based on data from the mitochondrial cytochrome b gene (1137 bp) and the nuclear RAG2 gene (882 bp). We find strong support for previous morphology‐based phylogenetic hypotheses, as well as the monophyly of most currently accepted flyingfish genera. However, the most diverse genus Cheilopogon is not monophyletic. Using our novel flyingfish topology, we examine previously proposed hypotheses for the origin and evolution of gliding. The results support the progressive transition from two‐wing to four‐wing gliding. We also use phylogenetic approaches to test the macroecological effects of two life history characters (e.g. egg buoyancy and habitat) on species range size in flyingfishes. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102, 161–174.     

Molecular phylogenetics of Sarcolaenaceae (Malvales), Madagascar's largest endemic plant family

With 72 species belonging to ten genera, Sarcolaenaceae are the largest and most diverse of Madagascar's endemic plant families. Comprising shrubs and trees, with members found in nearly all of this island nation's biogeographic regions, they are characterised by the presence of a distinctive extra‐floral involucre that is more or less accrescent, partially or completely covering or enveloping the fruit. We present the first molecular phylogenetic study of Sarcolaenaceae, using broad sampling that encompasses the family's taxonomic and morphological diversity, including 46 species representing all ten genera and sequence data from one nuclear marker (ITS) and three plastid regions (psaA‐ORF170, psbA‐trnH and rbcL), to reconstruct phylogenetic relationships using Bayesian inference and maximum likelihood. Results confirm the monophyly of Sarcolaenaceae and of eight of the ten genera; the monophyly of Rhodolaena remains ambiguous, although the taxa sampled were recovered in two well supported clades that are coherent in terms of morphology and geography. Only a single species of Eremolaena was available for study. The phylogenetic backbone of Sarcolaenaceae is not fully resolved, making it difficult to identify potential morphological synapomorphies or ecological preferences between and within genera. In the family, two monophyletic groups were, however, found [Pentachlaena + Eremolaena + Perrierodendron (Clade A) and Xyloolaena + Leptolaena + Sarcolaena + Mediusella + Xerochlamys (Clade B)] that are consistent with previous results based on morphology. Expanded species sampling and data from additional, more quickly evolving markers will be needed to produce a fully resolved phylogenetic tree for Sarcolaenaceae, which could then serve as a basis for exploring macroevolutionary patterns and processes in this remarkable family and reconstructing its biogeographic history.     

Recognition of a new generic‐level swallow taxon from central Africa

The forest swallow Petrochelidon fuliginosa is a little‐known species endemic to lowland forests in central Africa; for lack of access to high‐quality genetic material, the species has been omitted from all previous molecular phylogenetic studies of the swallows. The species is currently placed in the genus Petrochelidon, within the ‘mud‐nester’ clade of swallows, yet its plumage, morphology, and nesting behavior do not align well with those of other major swallow lineages. As a consequence, upon securing recent specimens and high‐quality tissue samples, we sequenced DNA from two mitochondrial genes and one nuclear marker to place this species in the swallow phylogenetic tree. Our results placed the forest swallow firmly within the ‘mud nester’ clade, but outside of the clade corresponding to Petrochelidon. This outcome led us to document and describe formally a distinct, generic‐level lineage of swallow endemic to the Lower Guinean forest region of central Africa.     

Dynamic colonization exchanges between continents and islands drive diversification in paradise‐flycatchers (Terpsiphone,Monarchidae)

Aim We use parametric biogeographical reconstruction based on an extensive DNA sequence dataset to characterize the spatio‐temporal pattern of colonization of the Old World monarch flycatchers (Monarchidae). We then use this framework to examine the role of dispersal and colonization in their evolutionary diversification and to compare plumages between island and continental Terpsiphone species. Location Africa, Asia and the Indian Ocean. Methods We generate a DNA sequence dataset of 2300 bp comprising one nuclear and three mitochondrial markers for 89% (17/19) of the Old World Monarchidae species and 70% of the Terpsiphone subspecies. By applying maximum likelihood and Bayesian phylogenetic methods and implementing a Bayesian molecular clock to provide a temporal framework, we reveal the evolutionary history of the group. Furthermore, we employ both Lagrange and Bayes‐ Lagrange analyses to assess ancestral areas at each node of the phylogeny. By combining the ancestral area reconstruction with information on plumage traits we are able to compare patterns of plumage evolution on islands and continents. Results We provide the first comprehensive molecular phylogenetic reconstruction for the Old World Monarchidae. Our phylogenetic results reveal a relatively recent diversification associated with several dispersal events within this group. Moreover, ancestral area analyses reveal an Asian origin of the Indian Ocean and African clades. Ancestral state reconstruction analyses of plumage characters provide an interpretation of the plumage differentiation on islands and continents. Ancestral plumage traits are inferred to be close to those of the Asian paradise‐flycatcher (Terpsiphone paradisi), and island species display a high degree of plumage autapomorphy compared with continental species. Main conclusions Terpsiphone paradisi is polyphyletic and comprises populations that have retained the ancestral plumage of the widespread Terpsiphone genus. The genus appears to have colonized south‐west Asia, the Indian Ocean and Africa from eastern Asia. The phylogeny and divergence time estimates indicate multiple simultaneous colonizations of the western Old World by Terpsiphone. These results reinforce a hypothesis of range expansions of a Terpsiphone paradisi‐like ancestor into eastern Asia and the western Old World.     

Molecular phylogeny of an endemic radiation of Cuban toads (Bufonidae: Peltophryne) based on mitochondrial and nuclear genes

Aim In this study we present a molecular phylogenetic and phylogeographical analysis of Peltophryne (Anura: Bufonidae), an endemic genus of Antillean toads, to investigate the spatial and temporal origins of the genus, with particular focus on the eight Cuban species. Location Greater Antilles, with extensive sampling of the Cuban archipelago. Methods We obtained DNA sequence data from two mitochondrial genes, cytochrome c oxidase subunit I (COI) and ribosomal RNA (16S), for 124 toads representing all eight Cuban species, and combined this with published data from Hispaniola (one of three species) and Puerto Rico (one of one species) to establish a molecular phylogeny for Peltophryne. In addition, we explored the phylogeographical structure of widespread Cuban species. For a subset of 42 toads we also obtained DNA sequence data from two nuclear genes, recombination activator‐1 (RAG‐1) and chemokine receptor 4 (CXCR‐4). We combined our molecular data with published DNA sequences from a global sample of bufonid toads to place the spatial and temporal origins of Peltophryne in the Caribbean within a fuller geographical and phylogenetic context. Results All phylogenetic analyses supported the monophyly of West Indian toads. The ancestor of Peltophyrne diverged from its mainland source around the Eocene–Oligocene boundary, with a subsequent radiation across the Caribbean islands taking place during the Miocene. Cuban species are monophyletic with a basal split in the early–middle Miocene that separates extant small‐bodied from large‐bodied species. Extensive mitochondrial DNA (mtDNA) sampling within widespread Cuban species revealed contrasting phylogeographical patterns. Peltophryne taladai and P. empusa showed deeply divergent lineages, whereas no geographical structure was observed in the widespread P. peltocephala. Main conclusions Our timeline for Peltophryne diversification is consistent with a biogeographical model requiring no long‐distance overwater dispersal. Although confidence intervals on divergence time estimates are wide, the stem age of Peltophyrne coincides with the hypothesized GAARlandia landspan or archipelago, which may have connected South America briefly with the Antilles. The ages of Peltophryne for Puerto Rico, Hispaniola and Cuba are consistent with a recently proposed vicariance scenario for the region. Our molecular results support the recognition of all eight species in Cuba, and provide evidence of possible cryptic species.     

Phylogeny of the shore crab family Grapsidae (Decapoda: Brachyura: Thoracotremata) based on a multilocus approach

The Grapsidae are a thoracotreme crab family with 40 species in eight genera (in their strict definition), and possess a number of morphological and molecular synapomorphies. Previous phylogenetic studies based on mitochondrial DNA markers established the monophyly of this family, but suggested possible paraphyly or polyphyly of some of the constituent genera. To test the validity of previous hypotheses, the present study reconstructed a molecular phylogeny of the grapsid crabs based on five molecular markers, including mitochondrial DNA markers and the first use of nuclear protein‐coding markers to address this issue. Monophyly of Grapsidae was confirmed, with the exception of the position of the monotypic genus Leptograpsodes. The polyphyly of the genus Pachygrapsus is consistent with previous molecular phylogenies, as members from this genus are dispersed throughout our gene tree. Grapsus and Planes were shown to be paraphyletic, with species of Pachygrapsus nested within them. Our study found incongruences between the currently adopted classification of the family, and hence taxonomic revisions will be needed. We hereby demonstrate the use of nuclear protein‐coding markers for high confidence reconstruction of decapod phylogenies, resolving most of the early splits that mitochondrial DNA markers alone are unable to tackle. © 2015 The Linnean Society of London     

Marine species formation along the rise of Central America: The anomuran crab Megalobrachium

The evolution of marine neotropical shallow water species is expected to have been greatly affected by physical events related to the emergence of the Central American Isthmus. The anomuran crab Megalobrachium, a strictly neotropical porcellanid genus, consists of four species in the West Atlantic (WA) and nine in the East Pacific (EP). Dispersal is limited to a relatively short planktonic phase, which lasts approximately two weeks. We obtained DNA sequences of three mitochondrial and two nuclear genes of all but one species of Megalobrachium to construct a time‐calibrated phylogeny of the genus and its historical phylogeography, based on the reconstruction of ancestral areas. The topology of the phylogenetic trees of Megalobrachium produced by Bayesian Inference (BI) and Maximum Likelihood (ML) were virtually congruent. The genus is monophyletic with respect to other porcellanids. Ancestral area reconstruction indicates that it arose in the eastern Pacific 18 million years ago and diversified into at least 13 species that are currently formally recognized and three additional species indicated by our data. Most morphological variation appears to have followed phylogenetic differentiation, though some cryptic speciation has also occurred. Four geminate clades in this genus implicate the gradual emergence of the Central American Isthmus in this diversification, but events preceding the final separation of the oceans as well as within‐ocean events after the cessation of water connections were also important.