Effects of urbanisation on the parasitoid community of a leafminer

Urbanisation may have detrimental effects on communities of parasitoids, affecting their species richness, abundance, and species dominance. Here we investigated the influence of the degree of urbanisation on parasitoid communities of Liriomyza commelinae (Frost) (Diptera: Agromyzidae), a leafminer of Commelina erecta L. (Commelinaceae), in the city of Córdoba, Argentina. To study changes in species richness, the specific composition of parasitic complexes and their degree of impact on the leafminer, 18 sampling sites from the centre to the outskirts of the city were selected and different variables indicative of urbanisation were quantified in each site. During January and February of 2005 and 2006, all mined leaves found in each plant patch were collected and the following variables were estimated: proportion of mined patches, abundance of the leafminer, total parasitoid species richness, total parasitism rates and parasitism due to the most abundant parasitoid species. The percentage of mined patches and leafminer abundance increased with urbanisation degree. Estimates of parasitoid species richness were not influenced by urbanisation degree but increased with species richness of mined plants. Changes in the specific composition of species along the urbanisation gradient were observed. Although parasitism by one of the species studied was higher in more urbanised sites of the city, the total parasitism rate of L. commelinae was not affected by urbanisation degree, species richness of mined plants or leafminer abundance. It appears that urbanisation benefits the herbivore species here studied but not through altering parasitoid activity. Changes in parasitoid community composition reflex dissimilar tolerance to environmental conditions displayed by different parasitoid species.     

Tradescantia fluminensis,an exotic weed affecting native forest regeneration in New Zealand: Ecological surveys,safety tests and releases of four biocontrol agents from Brazil

In the native range of Tradescantia fluminensis in SE Brazil surveys revealed a natural enemy biota attacking the plant that was rich in potential biocontrol agents for New Zealand (NZ), including nine fungi and 10 herbivorous insect species. Similar surveys in NZ, where T. fluminensis is an invasive exotic weed, revealed no specialist insect herbivores or pathogens. The Brazilian insect herbivores included leafmining, stemboring and gall-forming feeding guilds that were absent in NZ. Mean foliar damage levels per site on T. fluminensis were 7.8× higher for folivores in Brazil cf. NZ, and 21.2× higher for pathogens. The presence of rust pustules, or ‘brown lesions’, on leaves in Brazil was negatively associated with damage by folivores, perhaps indicating an antagonistic interaction. In contrast, damage by the white smut fungus, Kordyana sp., was not negatively associated with folivore damage. Mean dry biomass of T. fluminensis was significantly lower in Brazil (164 g m^?2) cf. NZ (455 g m^?2). In NZ, 85% of sites had biomass measures >200 g m^?2 (the previously determined threshold above which native forest regeneration fails). In Brazil, only 27% of sites had biomass measures >200 g m^?2. Among the insect herbivores, three chrysomelid beetles, Neolema ogloblini, Neolema abbreviata and Lema basicostata were prioritised as potential biocontrol agents. Their larvae cause potentially complementary damage to leaves, shoot-tips and mature stems, respectively. Several pathogens, including a rust, were rejected before we selected the Kordyana species. Host range testing of all four agents showed sufficient host-specificity for consideration for release in NZ. Neolema ogloblini and L. basicostata were field-released in NZ in 2011 and 2012, with the field-release of N. abbreviata due late 2012. An application to release Kordyana sp. in NZ has been made.     

History and current taxonomic status of genus Agrobacterium

The genus Agrobacterium was created a century ago by Conn who included it in the family Rhizobiaceae together with the genus Rhizobium. Initially, the genus Agrobacterium contained the non-pathogenic species Agrobacterium radiobacter and the plant pathogenic species Agrobacterium tumefaciens and Agrobacterium rhizogenes. At the end of the past century two new pathogenic species, Agrobacterium rubi and Agrobacterium vitis, were added to the genus. Already in the present century these species plus Agrobacterium larrymoorei were reclassified into genus Rhizobium. This reclassification was controversial and for a time both genus names were used when new species were described. Few years ago, after a taxonomic revision based on genomic data, the old species A. rhizogenes was maintained in the genus Rhizobium, the old species A. vitis was transferred to the genus Allorhizobium and several Rhizobium species were transferred to the genus Agrobacterium, which currently contains 14 species including the old species A. radiobacter, A. tumefaciens, A. rubi and A. larrymoorei. Most of these species are able to produce tumours in different plants, nevertheless the genus Agrobacterium also encompasses non-pathogenic species, one species able to nodulate legumes and one human pathogenic species. Taking into account that the species affiliations to five Agrobacterium genomospecies have not been determined yet, an increase in the number of species within this genus is expected in the near future.     

Ustilaginales of Commelinaceae

The seven reported smut fungi on Commelinaceae are revised. Of these, five are recognised and described:Ustilago aneilematis, U. burkillii, U. commelinae, U. nawaschinii andU. tinantiae. Entyloma commelinae is considered to be a doubtful species andU. rwandensis is a synonym ofU. aneilematis. A new species,Ustilago combensis (type onCommelina benghalensis) is proposed. A key to thesee species is presented.Studies in Heterobasidiomycetes, part 102     

Phylogeny, diversity, and species delimitation of the North American Round-Nosed Minnows (Teleostei: Dionda), as inferred from mitochondrial and nuclear DNA sequences

Accurate delimitation of species is a critical first step in protecting biodiversity. Detection of distinct species is especially important for groups of organisms that inhabit sensitive environments subject to recent degradation, such as creeks, springs, and rivers in arid or semi-desert regions. The genus Dionda currently includes six recognized and described species of minnows that live in clear springs and spring-fed creeks of Texas, New Mexico (USA), and northern Mexico, but the boundaries, delimitation, and characterization of species in this genus have not been examined rigorously. The habitats of some of the species in this genus are rapidly deteriorating, and many local populations of Dionda have been extirpated. Considering the increasing concerns over degradation of their habitat, and pending a more detailed morphological revision of the genus, we undertook a molecular survey based on four DNA regions to examine variation over the range of the genus, test species boundaries, and infer phylogenetic relationships within Dionda. Based on analyses of two mitochondrial (cytb and D-loop) and two nuclear (Rag1 and S7) DNA regions from specimens collected throughout the range of Dionda, we identified 12 distinct species in the genus. Formerly synonymized names are available for two of these species, and four other species remain undescribed. We also redefine the known range of six species. The limited distribution of several of the species, coupled with widespread habitat degradation, suggests that many of the species in this genus should be targets for conservation and recovery efforts.     

Systematics of the Monodelphic Species of Trichodoridae (Nematoda: Diphtherophorina) With Descriptions of a New Genus and Four New Species

To show the relationship of the monodelphic species of Trichodoridae with the nominal taxa, the genus Monotrichodorus is redefined, with the addition of one new species. The new genus Allotrichodorus is proposed on the basis of new species found in Brazil; and one new species is described in the genus Paratrichodorus.     

New species and records of Charisius Champion from Mexico and Central America (Coleoptera,Tenebrionidae, Alleculinae)

The species of the genus Charisius Champion, from Mexico and Central America are reviewed. The flightless genus Narses Champion, with one included species, N. subalatus Champion, is placed in synonymy with the genus Charisius. Four new species are described and illustrated, C. granulatus and C. punctatus (from Guatemala) and C. apterus and C. howdenorum (from Mexico). Charisius subalatus (Champion) is redescribed and illustrated. The species C. interstitialis Champion is placed in synonymy with C. zunilensis Champion. The genus is redescribed to include the four new species and N. subalatus. New distributional records are presented for all other species of the genus and a revised key is presented for identification of all the species of the genus.     

A two-gene phylogeny shows the lichen genus Niebla (Lecanorales) is endemic to the New World and does not occur in Macaronesia nor in the Mediterranean basin

The generic segregates of the widespread fruticose genus Ramalina (mostly based on empirical data on morphology, cortex anatomy and secondary metabolites) are studied using maximum parsimony, maximum likelihood and Bayesian analyses of nuclear LSU and ITS sequences. The species examined include the three species aggregates within Niebla from the western coasts of North America, all species except one assumed to belong to the same genus from Macaronesia and the Mediterranean basin, the type species of Dievernia and Ramalina, and representatives of the genus Fistulariella. The genus Niebla is strongly supported when restricted to species from the New World, and all species referred to it from Macaronesia and the Mediterranean basin belong to Ramalina (R. bourgeana, R. crispatula, R. cupularis, R. hamulosa, R. portosantana, R. rosacea, R. subwebbiana and R. webbii). No support is found for the genera Dievernia and Fistulariella. The internal topology of the large genus Ramalina is unresolved and needs further studies.     

The Megophthalmidia (Diptera,Mycetophilidae) of North America including eight new species

Megophthalmidia Dziedzicki is a small leiine genus (Mycetophilidae) with seven species described from the Neotropics and ten species from the Palearctic region. Two species of Megophthalmidia have been reported for North America. Recent collecting of Mycetophilidae in California and Arizona, however, shows current North American diversity of Megophthalmidia is at least on par to other regions of the world. Eight new species of Megophthalmidia are described here, increasing the number of Nearctic Megophthalmidia species to nine. Included is a particularly atypical member of the genus, M. saskia sp. n., which expands the genus concept of Megophthalmidia. Of the two species previously recorded for North America, only one actually belongs in the genus. Megophthalmidia occidentalis Johannsen, is fully described and illustrated. The other named species, M. marceda (Sherman) is illustrated and transferred to the genus Ectrepesthoneura Enderlein. A lectotype is designated for this species. A key to the species of Megophthalmidia of North America is provided. The biology of these flies is not yet known. Three of the new Megophthalmidia species – M. lenimenta, M. misericordia, and M. radiata – are only known to occur within small protected areas within the California State Park and UC Natural Reserve systems.     

Cryptic species and systematics of the hynobiid salamanders of the Liua–Pseudohynobius complex: Molecular and phylogenetic perspectives

Using mitochondrial DNA sequencing and allozyme electrophoresis, we examined 18 populations of the Liua–Pseudohynobius complex, endemic to China. Based on their phylogenetic affiliation and exhibited fixed allelic differences, the complex comprises at least six species, two of which are previously unknown cryptic species. The complex is clearly divided into two groups, genus Liua including Liua shihi and Liua tsinpaensis, and genus Pseudohynobius including Pseudohynobius flavomaculatus, Pseudohynobius shuichengensis and the two new species. The previously often used genus name Ranodon is inappropriate, because the type species of the genus, Ranodon sibricus, is distantly related to this complex. The species diversity among Chinese hynobiid salamanders are far from being recognized and further effort should be directed at extensive field collection in central and western China.     

Sumatrella chelonica gen. n., sp. n., a new remarkable genus and species from Indonesia,Sumatra (Acari,Uropodina, Oplitidae)

A new genus Sumatrella gen. n. is described and illustrated based on the new species Sumatrella chelonica sp. n. collected in Sumatra, Indonesia. The new genus belongs to the family Oplitidae based on its hypertrichous internal malae and the absence of strongly sclerotized structures on the dorsal shield. The new genus is closely related to the genus Chelonuropoda Sellnick, 1954 but the transverse furrow on ventral idiosoma close to coxae IV and the strongly sclerotized C-shaped dorsal line are missing in the new genus. These characters can be found in species of Chelonuropoda.     

A Key and Diagnostic Compendium to the Species of the Genus Tylenchorhynchus Cobb, 1913 (Nematoda: Belonolaimidae)

An identification key to 111 species of Tylenchorhynchus is given. Tylenchorhynchus is defined as containing only those species with four incisures in the lateral field. A compendium providing the most important diagnostic characters for use in identification of species is included as a supplement to the key. Some species in a related but unnecessary genus were placed in the genus Tylenchorhynchus, based on morphological structures and logical groupings of the species. Bitylenchus iphilus is transferred to Tylenchorhynchus. The diagnosis of Tylenchorhynchus is emended, and a list of all the valid species of the genus is given. The characters most useful for separating species are the stylet length, shape of lip region, number of lip annules, shape of tail and tail terminus, number of tail annules, and position of vulva (V%). As defined in the paper, the genus currently is composed of 111 valid species.     

Comparison of ribosomal dna nucleotide sequences of the mosquito genera Aedes and Ochlerotatus (Diptera: Culicidae: Aedini)

Nucleotide rDNA sequences of 9 species of the mosquito genus Ochlerotatus and 2 species of the genus Aedes were obtained and compared. Variation both within and between these genera was characterized. The phylogenetic relationships among the studied species of Ochlerotatus generally correspond to the grouping of species based on morphological characters.     

Taxonomic revision of the Neotropical stalk-eyed fly Plagiocephalus Wiedemann (Diptera,Ulidiidae, Ulidiinae)

Plagiocephalus is a genus composed of three species mainly recognized by the males with stalked-eyes. Plagiocephalus lobularis is distributed from Northeastern Brazil to North of Argentina, P. latifrons is distributed from Mexico to Bolivia, and P. intermedius occurs in Costa Rica. We review the species of the genus, providing new diagnostic characters, an identification key, and new information on the terminalia of Plagiocephalus. Also, we update the geographic distribution of the species of the genus.     

A new genus of soft coral (Cnidaria,Octocorallia) from the Republic of Congo (Pointe-Noire Region)

A new genus of soft coral from the Republic of Congo is described, Complexum gen. n. Nine West African octocoral species previously described in the genus Alcyonium by Tixier-Durivault (1955) are referred to this new genus, and a new species is described and figured, Complexum pusillum sp. n. The new species is characterized by having encrusting growth form and abundant spiny clubs in the surface of the polyparium. It colonizes shallow calcareous rocky banks (5 to 20 m depth) existing in coastal water of the region of Pointe-Noire. Based on molecular phylogeny this new genus is well separated from Alcyonium species.     

The Middle–Late Ordovician brachiopod Plectorthis from North America and its paleobiogeographic significance

Plectorthis is a commonly reported Late Ordovician brachiopod genus from Laurentia and several other tectonic plates. Examination of shells from the Cincinnati Arch type area shows that species previously assigned to the genus have a considerable range of variability, such as ribbing style, shell outline, and musculature. The type species, Orthis plicatella Hall, 1847 is characterized by generally simple costae, with double-rowed aditicules on each rib, and a cordate ventral muscle field. Some species previously attributed to Plectorthis have a subtriangular ventral muscle field and hence a closer affinity to the plaesiomyid genus Austinella. Orthis fissicosta is here demoted to a subspecies of Plectorthis plicatella based on its similar ribbing style to some specimens of the type species. In Laurentia, Plectorthis first appeared in the Darriwilian–Sandbian boundary interval, achieved a relatively high species diversity and wide paleogeographic distribution in pericratonic seas during the early Katian; the subequatorial species attained a notably larger shell than those in the higher paleotropics. The genus did not invade the intracratonic basins of Laurentia and became extinct by the late Katian.     

Cetradonia,a new genus in the new family Cetradoniaceae (Lecanorales,Ascomycota)

Abstract:A taxonomic revision of the lichen genus Gymnoderma Nyl. sensu Yoshimura & Sharp (Cladoniaceae) based on an integrative analysis of polyphasic characters supports the segregation of a new genusCetradonia J.-C.Wei & Ahti in a new family Cetradoniaceae J.-C.Wei & Ahti. The monotypic genus and family are based on Cladonia linearis Evans. In addition, two species are recognized in genus Neophyllis F. Wilson and two species are retained in the genus Gymnoderma Nyl. of the Cladoniaceae.     

Phylogenetic Relationships of American Willows (Salix L., Salicaceae)

Salix L. is the largest genus in the family Salicaceae (450 species). Several classifications have been published, but taxonomic subdivision has been under continuous revision. Our goal is to establish the phylogenetic structure of the genus using molecular data on all American willows, using three DNA markers. This complete phylogeny of American willows allows us to propose a biogeographic framework for the evolution of the genus. Material was obtained for the 122 native and introduced willow species of America. Sequences were obtained from the ITS (ribosomal nuclear DNA) and two plastid regions, matK and rbcL. Phylogenetic analyses (parsimony, maximum likelihood, Bayesian inference) were performed on the data. Geographic distribution was mapped onto the tree. The species tree provides strong support for a division of the genus into two subgenera, Salix and Vetrix. Subgenus Salix comprises temperate species from the Americas and Asia, and their disjunction may result from Tertiary events. Subgenus Vetrix is composed of boreo-arctic species of the Northern Hemisphere and their radiation may coincide with the Quaternary glaciations. Sixteen species have ambiguous positions; genetic diversity is lower in subg. Vetrix. A molecular phylogeny of all species of American willows has been inferred. It needs to be tested and further resolved using other molecular data. Nonetheless, the genus clearly has two clades that have distinct biogeographic patterns.