Der Lebenszyklus vonPorphyrostromium obscurum (Bangiophyceae,Rhodophyta)

Studies on the sexuality and the heteromorphous life cycle ofErythrotrichia ciliaris provided decisive criteria for the establishment of the genusErythrotrichopeltis (Kornmann, 1984). This genus was transferred by Wynne (1986) toPorphyrostromium Trevisan 1848. In the present studyErythrotrichia obscura, the original species of Berthold's (1882) classical observations on the sexuality of this genus, is incorporated toPorphyrostromium. Previously regarded as synonyms,Porphyrostromium ciliare (Carm. ex Harv.) Wynne andP. obscurum (Berth.) nov. comb. proved to be distinct species, differing both in the filamentous and in the peltoid phases of their life cycle. The relationship betweenP. ciliare andP. boryanum (Montagne) Trevisan, type species of the genus, may only be elucidated by future investigations on the basis of field collected material.      

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.     

Neglected refugia of biodiversity: mountainous regions in Mozambique and Malawi yield two novel freshwater crab species (Potamonautidae: Potamonautes)

Phylogenetic relationships amongst the southern African freshwater crab fauna are reinvestigated following the recent collection of morphologically distinct Potamonautes specimens from remote mountainous regions in Malawi and Mozambique. Specimens were subjected to DNA sequencing of three mtDNA loci, cytochrome c oxidase subunit I (COI), 12S rRNA, and 16S rRNA and compared to the 14 described species from the region. Phylogenetic analysis using maximum parsimony and Bayesian inference revealed the presence of two novel evolutionary lineages. The phylogeny demonstrates that Potamonautes obesus (A. Milne‐Edwards, 1868) is sister to a morphologically distinct novel species from Mount Namuli in Mozambique. Two sympatric and genetically distinct species from Mount Mulanje, in Malawi (forms A and B) were recognized. Form B is sister to the large‐bodied South African riverine freshwater crabs and represents a novel lineage whereas the remaining species (form A) from Mulanje, in Malawi was sister to samples from Mounts Inago and Mabu, and in Mozambique was identified as Potamonautes choloensis (Chace, 1953). The two novel evolutionary lineages were genetically distinct and morphologically different from the described species in each of the respective regions. Two new freshwater crab species Potamonautes namuliensis sp. nov. and Potamonautes mulanjeensis sp. nov. , are described in the present study. The samples from Mount Mulanje in Malawi, and Mounts Mabu and Inago in Mozambique represent new distribution records for Potamonautes choloensis. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 498–509.     

Recognition of a species-poor, geographically restricted but morphologically diverse Cape lineage of diving beetles (Coleoptera: Dytiscidae: Hyphydrini)

Aim To establish the phylogeny and geographical origin of the genera of the diving beetle tribe Hyphydrini in order to investigate the origin of differences in geographical range size, intrageneric species‐richness and morphological disparity. In particular, we tested the hypothesis that the geographically restricted, species‐poor and morphologically deviating genera found in the Cape Region of South Africa are a paraphyletic pool of ‘primitive’ Hyphydrini, from which the morphologically more uniform, species‐rich and geographically widespread genera have originated. Location Worldwide, with special reference to the Cape Region of South Africa. Methods We constructed a genus‐level molecular phylogeny of 10 of the 14 known genera of Hyphydrini, including the five endemic to the Cape Region, using sequences from four gene fragments (two mitochondrial, rrnL and cox1; and two nuclear, 18S rRNA and histone 3, c. 2200 bp). Phylogenies were built with Bayesian methods, and linearized using penalized likelihood. Morphological disparity was characterized by correspondence analysis of a data matrix of 21 binary characters. We compare morphological disparity among groups using distance to the global and local centroids and the total range of morphospace occupied. Geographical range was estimated using the number of 6° longitude × 8° latitude Universal Transverse Mercator squares known to contain any species of each genus. Results Hyphydrini is made up of four well supported clades of similar relative genetic divergence: (1) Hyphydrus (Old World plus Australasia, 133 species), (2) the five endemic genera of the Cape Region, sister to Hovahydrus (Madagascar) (10 species), (3) Desmopachria (America, 92 species), and (4) two Oriental genera (Microdytes and Allopachria, 68 species). The morphological disparity within the Cape Region lineage has apparently increased with time, with the two genera closest to the global centroid paraphyletic and basal with respect to the three more recent, morphologically deviating genera. Differences in the number of species between each of the four lineages were not significant. The correlation between the number of species in each lineage and geographical range extent was highly significant, with the low species number of the Cape Region (six) well within the 95% confidence interval of the regression. Main conclusions Contrary to expectations, the species‐poor, morphologically deviating endemic genera of the Cape Region are not a ‘primitive’ relictual pool from which the widespread, species‐rich and morphologically uniform genera have originated. The morphological disparity within the Cape lineage has increased with time, and the apparent lack of species‐level diversification disappears when species–area relationships are considered. A major unanswered question is why one of the four main lineages of Hyphydrini has remained restricted to a very reduced area (the Cape Region), but despite this evolved the highest degree of morphological diversity seen in the tribe.     

Molecular phylogeny of the tribe Erotini with description of a new genus from China (Coleoptera: Lycidae)

Erotini is a small tribe of net‐winged beetles known from the northern temperate zone. We investigated relationships and limits of tribes and genera using a molecular phylogeny inferred from rrnL, cox1 and nad5 mtDNA fragments. Lopheros Leconte, 1881 and Pseudaplatopterus Kleine, 1940 were inferred in current molecular analyses as terminal lineages within Erotini. Therefore, we consider Lopherotini Kazantsev, 2012 and Pseudaplatopterina Kazantsev, 2012 as junior synonyms of Erotini Leconte, 1881. The Platycis genus group comprises 19 species representing several genus‐group taxa previously placed in Platycis s. l. Konoplatycis Nakane, 1969 was recovered as a deeply rooted lineage of Erotini and we inferred another independent lineage for which we propose a new genus Sinoplatycis gen. nov. Additionally, we studied the diversity of Platycis s. l. in Asia, found their highest diversity in the temperate forest habitats of Eastern Asia and inferred the paraphyletic character of the subgenus Erotides s. str. Five new species are described from China: Sinoplatycis cardinalis sp. nov. , S. zhani sp. nov. (type species of Sinoplatycis gen. nov. ), Erotides brunnescens sp. nov. , E. pusillus sp. nov. and E. slipinskii sp. nov. The molecular phylogeny shows deep splits of Japanese species with respect to the continental Eurasian fauna and the role of shallow seas and mountain systems in the diversification of the Platycis genus group.     

MOLECULAR PHYLOGENY OF SELECTED SPECIES OF THE ORDER DINOPHYSIALES (DINOPHYCEAE)—TESTING THE HYPOTHESIS OF A DINOPHYSIOID RADIATION1

Almost 80 years ago, a radiation scheme based on structural resemblance was first outlined for the marine order Dinophysiales. This hypothetical radiation illustrated the relationship between the dinophysioid genera and included several independent, extant lineages. Subsequent studies have supplied additional information on morphology and ecology to these evolutionary lineages. We have for the first time combined morphological information with molecular phylogenies to test the dinophysioid radiation hypothesis in a modern context. Nuclear‐encoded LSU rDNA sequences including domains D1‐D6 from 27 species belonging to Dinophysis Ehrenb., Ornithocercus F. Stein, Phalacroma F. Stein, Amphisolenia F. Stein, Citharistes F. Stein, and Histioneis F. Stein were obtained from the Indian Ocean. Previously, LSU rDNA has only been determined from one of these. In Bayesian analyses, Amphisolenia formed a long basal clade to the other dinophysioids. These diverged into two separate lineages, the first comprised species with a classical Phalacroma outline, also including the type species P. porodictyum F. Stein. Thus, we propose to reinstate the genus Phalacroma. The relationship between the genera in the second lineage was not well resolved. However, the molecular phylogeny supported monophyly of Histioneis and Citharistes and showed the genus Dinophysis to be polyphyletic and in need of a taxonomic revision. Species of Ornithocercus grouped with Citharistes, but this relationship remained unresolved. The phylogenetic trees furthermore revealed convergent evolution of several morphological characters in the dinophysioids. According to the molecular data, the dinophysioids appeared to have evolved quite differently from the radiation schemes previously hypothesized. Four dinophysioid species had identical LSU rDNA sequences to other well‐established species.     

Taxonomic revision of Chlamydomonas subg. Amphichloris (Volvocales,Chlorophyceae), with resurrection of the genus Dangeardinia and descriptions of Ixipapillifera gen. nov. and Rhysamphichloris gen. nov.

Chlamydomonas (Cd.) is one of the largest but most polyphyletic genera of freshwater unicellular green algae. It consists of 400–600 morphological species and requires taxonomic revision. Toward reclassification, each morphologically defined classical subgenus (or subgroup) should be examined using culture strains. Chlamydomonas subg. Amphichloris is characterized by a central nucleus between two axial pyrenoids, however, the phylogenetic structure of this subgenus has yet to be examined using molecular data. Here, we examined 12 strains including six newly isolated strains, morphologically identified as Chlamydomonas subg. Amphichloris, using 18S rRNA gene phylogeny, light microscopy, and mitochondria fluorescent microscopy. Molecular phylogenetic analyses revealed three independent lineages of the subgenus, separated from the type species of Chlamydomonas, Cd. reinhardtii. These three lineages were further distinguished from each other by light and fluorescent microscopy—in particular by the morphology of the papillae, chloroplast surface, stigmata, and mitochondria—and are here assigned to three genera: Dangeardinia emend., Ixipapillifera gen. nov., and Rhysamphichloris gen. nov. Based on the molecular and morphological data, two to three species were recognized in each genus, including one new species, I. pauromitos. In addition, Cd. deasonii, which was previously assigned to subgroup “Pleiochloris,” was included in the genus Ixipapillifera as I. deasonii comb. nov.     

ESSENTIAL OILS AS TAXONOMIC AIDS IN THE CLASSIFICATION OF DICHANTHIUM PARVIFLORUM

Essential oil components and gross morphological characters are closely correlated in Dichanthium parviflorum (R. Br.) de Wet et Harlan (Gramineae) and related species. Different species, varieties, and geographical races, as well as hybrids between them, can be identified on the basis of absence or presence and quantity of essential oil components. The morphologically variable D. parviflorum was subdivided into four varieties: var. parviflorum, var. capilliflorum (Steud.) de Wet et Harlan comb. nov., var. mutispiculum (Ohwi) de Wet et Harlan comb. nov., and var. spicigerum (S. T. Blake) de Wet et Harlan comb. nov. These varieties differ from each other morphologically in having respectively racemes with 1-4 and awned, 3-5 and awned, 1-2 and awnlass, and 4-10 and awned spikelet pairs per raceme.     

Non‐monophyly of Bostrychia simpliciuscula (Ceramiales,Rhodophyta): Multiple species with very similar morphologies,a revised taxonomy of cryptic species

The discovery of a plethora of cryptic species in many algal groups has led to speculation as to the causes of this observation and has affected taxonomy, with reluctance to give names to species that look identical. While this is defensible for monophyletic cryptic species complexes, both our understanding of similar morphologies (crypsis) and nomenclature is challenged when we encounter non‐monophyletic ‘cryptic’ species. Bostrychia simpliciuscula is a wide‐ranging species in which multiple cryptic species are known. Our increased sampling shows that this species consists of four lineages that do not form a clade, but lineages are sister to species with different morphologies. Careful morphological examination shows that characters, especially branched monosiphonous laterals and rhizoid morphology in haptera, are able to distinguish these four lineages into two groups, that are still not monophyletic. The similar morphologies in these lineages could be due to convergence, but not developmental constraints or lack of time to diverge morphologically; or possibly maintenance of a generalized body plan. These lineages appear to have specific biogeographic patterns and these will be used to propose a new taxonomy. B. simpliciuscula is now confined to the tropics. Another of these lineages matches a previously described species, B. tenuissima, that was synonymized with B. simpliciuscula and is from cold temperate Australasia, and is resurrected. Another lineage is found in Japan in which a previous name is also available, B. hamana‐tokidae; the last lineage is found in central New South Wales, morphologically it resembles B. tenuissima, with which it overlaps in distribution around Sydney, and is named as a new species, B. kingii sp. nov.     

SYSTEMATICS OF GRATELOUPIA FILICINA (HALYMENIACEAE,RHODOPHYTA), BASED ON rbcL SEQUENCE ANALYSES AND MORPHOLOGICAL EVIDENCE,INCLUDING THE REINSTATEMENT OF G. MINIMA AND THE DESCRIPTION OF G. CAPENSIS SP. NOV.1

Grateloupia filicina (C. Agardh) Lamouroux, originally described from the Mediterranean Sea, has long been considered a textbook example of a marine red alga with a cosmopolitan distribution. An rbcL‐based molecular phylogeny, encompassing samples covering the entire geographic distribution of the species, revealed a plethora of “cryptic” species, whereby the presence of genuine G. filicina is limited to the Mediterranean basin. The phylogeny revealed a strong biogeographic imprint, with specimens from temperate regions resolved in clades composed of species inhabiting the same geographic region. Presence of widely divergent morphologies in the temperate clades indicated that several lineages have converged independently to a G. filicina‐type morphology. Tropical representatives are resolved in a single clade with very uniform G. filicina‐type morphology and pairwise sequence divergences that are lower than the average divergence observed in temperate lineages. This, combined with a lack of clear geographic structure among the tropical lineages, may indicate a more recent divergence with long‐range dispersal capacities. Violations to the biogeographic signal in temperate lineages seemed to be due to either inadequate taxonomy or recent introductions. Grateloupia minima P. & H. Crouan, a taxon placed in synonymy under G. filicina, is reinstated as a separate species distributed in the northeast Atlantic Ocean. Grateloupia capensis sp. nov. is described to accommodate specimens from South Africa with a G. filicina‐type morphology, and G. filicina var. luxurians is elevated to species status. Morphological and anatomical characters were put forward that support the distinctiveness of these three distinct species.     

Navigating the mtDNA road map out of the morphological maze: interpreting morphological variation in the diverse Monomorium rothsteini (Forel) complex (Hymenoptera: Formicidae)

Monomorium is a large and diverse ant genus with speciose radiations in both the Afrotropical and Australian regions. According to the most recent taxonomic revision, many Australian species are characterised by very broad distributions and variable morphology, which suggests that some species may be unrecognised species complexes. With a continent‐wide distribution and diverse yet overlapping morphology, M. rothsteini (Forel) is representative of the greater challenge that exists in Australian Monomorium systematics. Here we investigate species boundaries in M. rothsteini using a molecular phylogenetic framework to interpret the complex overlap of nine morphological characters (with 31 states) and examine biogeographic relationships among the lineages. Bayesian inference resolved 38 mtDNA lineages that were morphologically separable, at least from their sister lineage. Although the morphological characters were intermixed across the phylogeny, instances of inseparable morphology among sister clades was rare. Seventeen lineages exhibited complete morphological overlap with one or more other lineages and could not be separated by Principal Component Analysis based on 12 morphometric variables. Two‐thirds of all lineages occurred sympatrically with one or more both genetically and morphologically divergent lineages. The two nuclear markers EF1αF2 and wingless were used to generate haplotype networks which were characterised by a star‐like pattern indicative of a rapid and recent radiation. Several haplotypes for both nuclear gene regions were shared among individuals occurring in separate mtDNA clades which we were also unable to distinguish morphologically or that were occurring in sympatry, indicating possible introgression in both the mtDNA and nuclear genomes. Clear biogeographic affinities among samples within a lineage were detected but there was no overall pattern in the biogeographic relationships among the lineages. We conclude that M. rothsteini is a large species complex that has undergone a complex evolutionary history following aridification of the Australian continent, and discuss the implications of this conclusion for the systematics of Australian Monomorium more generally.     

Aphis (Hemiptera: Aphididae) species groups found in the Midwestern United States and their contribution to the phylogenetic knowledge of the genus

A phylogeny of the genus Aphis Linnaeus, 1 758 was built primarily from specimens collected in the Midwest of the United States. A data matrix was constructed with 68 species and 41 morphological characters with respective character states of alate and apterous viviparous females. Dendrogram topologies of analyses performed using UPGMA (Unweighted Pair Group Method with Arithmetic Mean), Maximum Parsimony and Bayesian analysis of Cytochrome Oxidase I, Elongation Factor 1‐α and primary endosymbiont Buchnera aphidicola 16S sequences were not congruent. Bayesian analysis strongly supported most terminal nodes of the phylogenetic trees. The phylogeny was strongly supported by EF1‐α, and analysis of COI and EF1‐α molecular data combined with morphological characters. It was not supported by single analysis of COI or Buchnera aphidicola 16S. Results from the Bayesian phylogeny show 4 main species groups: asclepiadis, fabae, gossypii, and middletonii. Results place Aphis and species of the genera Protaphis Börner, 1952, Toxoptera Koch, 1856 and Xerobion Nevsky, 1928 in a monophyletic clade. Morphological characters support this monophyly as well. The phylogeny shows that the monophyletic clade of the North American middletonii species group belong to the genus Protaphis: P. debilicornis (Gillette & Palmer, 1929 ), comb. nov., P. echinaceae (Lagos and Voegtlin, 2009 ), comb. nov., and P. middletonii (Thomas, 1879 ). The genus Toxoptera should be considered a subgenus of Aphis (stat. nov.). The analysis also indicates that the current genus Iowana Frison, 1954 should be considered a subgenus of Aphis (stat. nov.).     

Repeated vicariance of Eurasian songbird lineages since the Late Miocene

Aim The evolution of avian speciation patterns across much of Eurasia is under‐explored. Excepting phylogeographic patterns of single species, or speciation involving the Himalayas, there has been no attempt to understand the evolution of avian distributional patterns across the rest of the continent. Within many genera there is a pattern of (presumed) sister species occurring in adjacent areas (western, eastern or southern Eurasia), yet this pattern cannot be explained by existing biogeographic barriers. My aim was to examine the possible role of climate‐driven vicariance events in generating avian distributions. Location Eurasia. Methods I constructed a molecular phylogeny of Phoenicurus redstarts, and assembled phylogenetic data from published studies of seven other Eurasian bird genera. On each phylogeny, I assessed the distributional patterns of species and clades relative to refugial areas in western, eastern and southern Eurasia. I also estimated the timing of lineage divergences via a molecular clock, to determine whether distributional patterns can be explained by well‐defined periods of climate change in Eurasia that are recorded from dated sediments in the Chinese Loess Plateau. Results Species relationships in a well‐supported phylogeny of Phoenicurus show a pattern of distributions consistent with repeated speciation in major refugial areas, where one lineage is isolated in a single area of Eurasia relative to its sister lineage. This same pattern is evident in Eurasian Turdus thrushes, and six additional avian genera distributed across Eurasia. Molecular clock dating indicates that divergences within each genus are the result of multiple rounds of speciation in refugia through time, during major climate‐driven episodes of vicariance. Main conclusions Analyses revealed substantial evidence supporting a repeated, non‐random pattern of speciation within and across eight songbird lineages since the Late Miocene. The pattern of speciation supports a model of isolation in refugia during major episodes of vicariance, specifically periods of either intensified desertification of Central Asia or Eurasian glacial cycles. The densely sampled clades used here preclude inter‐continental dispersal as an alternative explanation for distributions. The signature of climate‐driven vicariance across epochs is, given the absence of extant biogeographic barriers, a suitable hypothesis to explain major lineage divergences in widely distributed Eurasian songbird lineages.     

Toward Modern Classification of Eustigmatophytes,Including the Description of Neomonodaceae Fam. Nov. and Three New Genera1

The class Eustigmatophyceae includes mostly coccoid, freshwater algae, although some genera are common in terrestrial habitats and two are primarily marine. The formal classification of the class, developed decades ago, does not fit the diversity and phylogeny of the group as presently known and is in urgent need of revision. This study concerns a clade informally known as the Pseudellipsoidion group of the order Eustigmatales, which was initially known to comprise seven strains with oval to ellipsoidal cells, some bearing a stipe. We examined those strains as well as 10 new ones and obtained 18S rDNA and rbcL gene sequences. The results from phylogenetic analyses of the sequence data were integrated with morphological data of vegetative and motile cells. Monophyly of the Pseudellipsoidion group is supported in both 18S rDNA and rbcL trees. The group is formalized as the new family Neomonodaceae comprising, in addition to Pseudellipsoidion, three newly erected genera. By establishing Neomonodus gen. nov. (with type species Neomonodus ovalis comb. nov.), we finally resolve the intricate taxonomic history of a species originally described as Monodus ovalis and later moved to the genera Characiopsis and Pseudocharaciopsis. Characiopsiella gen. nov. (with the type species Characiopsiella minima comb. nov.) and Munda gen. nov. (with the type species Munda aquilonaris) are established to accommodate additional representatives of the polyphyletic genus Characiopsis. A morphological feature common to all examined Neomonodaceae is the absence of a pyrenoid in the chloroplasts, which discriminates them from other morphologically similar yet unrelated eustigmatophytes (including other Characiopsis-like species).