Showing papers in "Various articles in 2013"

Insular woodiness on the Canary Islands: a remarkable case of convergent evolution

Abstract: Premise of research. One of the most conspicuous aspects of island floras is the relatively high proportion of woody species. Often, but not always, these woody species have developed wood on the islands and have evolved from herbaceous continental ancestors, a phenomenon known as insular woodiness. Shifts from herbaceousness toward increased woodiness also occur on continents (the broader term “secondary woodiness” is more appropriate here and includes insular woodiness), but comprehensive worldwide knowledge about secondary woodiness within angiosperms remains lacking. We update hypotheses regarding the herbaceous ancestry of woody Canarian lineages in a molecular phylogenetic context and investigate the possible link of secondary woodiness and paedomorphic wood features in the Carlquistian sense. Methodology. We have assembled available literature data from molecular phylogenetic studies, wood anatomical descriptions, floras, and taxonomic revisions to identify the native secondarily woody taxa. Pivotal results. In total, at least 220 native Canary Island species of flowering plants, from 34 genera representing 15 families, are truly insular woody. This represents a significant portion of the native nonmonocot angiosperm species on the Canaries, and all of the insular woody species have paedomorphic wood features in the Carlquistian sense, although this wood anatomical syndrome might be more related to particular life forms. The majority of these insular woody groups typically grow in the markedly dry lowland regions, suggesting a possible link between secondary woodiness and increased drought resistance. Conclusions. The Canary Island flora is characterized by at least 38 independent shifts toward insular woodiness, representing an important portion of the endemic angiosperms on the archipelago. These convergent evolutionary events emphasize the remarkable lability in growth forms between herbaceous and woody lineages, but it remains puzzling which environmental variables trigger these shifts and how these independent shifts are regulated genetically.

Something gone awry: unsolved mysteries in the evolution of asymmetric animal genitalia

Abstract: The great diversity in genital shape and function across and within the animal phyla hamper the identification of specific evolutionary trends that stretch beyond the limits of the group under study. Asymmetry might be a trait in genital morphology that could play a unifying role in the evolutionary biology of genitalia. Here, I review the current knowledge on the taxonomic distribution, phylogenetic patterns, genetics, development, and ecology of asymmetric (chiral) genitalia. Asymmetric genitalia (male as well as female) have evolved from bilaterally symmetric ones (and sometimes vice versa), innumerous times in most animal taxa with internal fertilisation, and especially in Platyhelminthes, Arthropoda, Nematoda, and Chordata. In groups with asymmetric genitalia, chiral reversal (where species carry genitalia that are the mirror image of those in other, congeneric, species) is common, but antisymmetry (both mirror images present within a species) is rare. Although indications exist that, at least in insects, asymmetry evolves as a compensatory response to the evolution of maledominant mating positions, many mysteries remain. Main questions are: (i) is genital asymmetry developmental-genetically linked with other (visceral, external) asymmetries? (ii) is genital asymmetry usually correlated with a change in mating position? (iii) is asymmetry more likely to evolve in response to cryptic female choice or sexually-antagonistic coevolution? (iv) why is antisymmetry so rare and how does chiral reversal evolve? Based on an overview of the taxonomic patterns, I advocate a research program that makes use of the simple, binary nature of left-right asymmetry to test hypotheses for its evolution with experimental and comparative methods. I also provide tables with full or summarised data on (a) genital asymmetry across all animal phyla with internal fertilisation; (b) genera with dextral as well as sinistral species; (c) species with dextral as well as sinistral individuals; (d) genera with symmetric as well as asymmetric species; (e) species with symmetric as well as asymmetric individuals.

Genetic patterns in European Geometrid Moths revealed by the Barcode Index Number (BIN) System

Abstract: Background: The geometrid moths of Europe are one of the best investigated insect groups in traditional taxonomy making them an ideal model group to test the accuracy of the Barcode Index Number (BIN) system of BOLD (Barcode of Life Datasystems), a method that supports automated, rapid species delineation and identification. Methodology/Principal Findings: This study provides a DNA barcode library for 219 of the 249 European geometrid moth species (88%) in five selected subfamilies. The data set includes COI sequences for 2130 specimens. Most species (93%) were found to possess diagnostic barcode sequences at the European level while only three species pairs (3%) were genetically indistinguishable in areas of sympatry. As a consequence, 97% of the European species we examined were unequivocally discriminated by barcodes within their natural areas of distribution. We found a 1:1 correspondence between BINs and traditionally recognized species for 67% of these species. Another 17% of the species (15 pairs, three triads) shared BINs, while specimens from the remaining species (18%) were divided among two or more BINs. Five of these species are mixtures, both sharing and splitting BINs. For 82% of the species with two or more BINs, the genetic splits involved allopatric populations, many of which have previously been hypothesized to represent distinct species or subspecies. Conclusions/Significance: This study confirms the effectiveness of DNA barcoding as a tool for species identification and illustrates the potential of the BIN system to characterize formal genetic units independently of an existing classification. This suggests the system can be used to efficiently assess the biodiversity of large, poorly known assemblages of organisms. For the moths examined in this study, cases of discordance between traditionally recognized species and BINs arose from several causes including overlooked species, synonymy, and cases where DNA barcodes revealed regional variation of uncertain taxonomic significance.

Pectinoidea (Bivalvia: Propeamussiidae and Pectinidae) from the Panglao region, Philippine Islands

Abstract: Sixty one Pectinoidea species (11 Propeamussiidae and 50 Pectinidae) collected by the 2004 Panglao Marine Biodiversity Project (PMBP) to Panglao, Philippines, and the PANGLAO 2005 Deep-Sea Cruise are described. One Propeamussiidae species is new to science: Parvamussium largoi spec. nov. Three pectinoidean species (1 Propeamus-siidae, 2 Pectinidae) are new records for the Philippines: Similipecten eous (Melvill in Melvill & Standen, 1907), "Mimachlamys" kauaiensis (Dall, Bartsch & Rehder, 1938) and Haumea rehderi (Grau, 1960). Records of species in the ZMA collection (now Naturalis Biodiversity Center) from the Philippines, not sampled by PMBP 2004 and PANGLAO 2005, are given. Amussium electrum Pelseneer, 1911 is newly synonymised with Propeamussium caducum (E.A. Smith, 1885). Type data, references, descriptions, horizontal and vertical distribution and habitat of each species are provided.

Forensic identification of Indian Snakeroot (Rauvolfia serpentina Benth. ex Kurz) using DNA barcoding

Abstract: Indian snakeroot (Rauvolfia serpentina) is a valuable forest product, root extracts of which are used as an antihypertensive drug. Increasing demand led to overharvesting in the wild. Control of international trade is hampered by the inability to identify root samples to the species level. We therefore evaluated the potential of molecular identification by searching for species-specific DNA polymorphisms. We found two species-specific indels in the rps16 intron region for R. serpentina. Our DNA barcoding method was tested for its specificity, reproducibility, sensitivity and stability. We included samples of various tissues and ages, which had been treated differently for preservation. DNA extractions were tested in a range of amplification settings and dilutions. Species-specific rps16 intron sequences were obtained from 79 herbarium accessions and one confiscated root, encompassing 39 different species. Our results demonstrate that molecular analysis provides new perspectives for forensic identification of Indian snakeroot.

Hyperdominance in the Amazonian tree flora

Abstract: The vast extent of the Amazon Basin has historically restricted the study of its tree communities to the local and regional scales. Here, we provide empirical data on the commonness, rarity, and richness of lowland tree species across the entire Amazon Basin and Guiana Shield (Amazonia), collected in 1170 tree plots in all major forest types. Extrapolations suggest that Amazonia harbors roughly 16,000 tree species, of which just 227 (1.4%) account for half of all trees. Most of these are habitat specialists and only dominant in one or two regions of the basin. We discuss some implications of the finding that a small group of species—less diverse than the North American tree flora—accounts for half of the world’s most diverse tree community.

The Bupleurum (Apiaceae) feeding species of Trifurcula (Glaucolepis): new species, biology and distribution (Lepidoptera: Nepticulidae)

Abstract: The Bupleurum feeding species of Trifurcula (Glaucolepis) Braun, 1917 are revised. Five species are recognised: T. bupleurella (Chretien, 1907), T. sanctibenedicti Klimesch, 1979, T. megaphallus van Nieukerken, Z. Lastůvka & A. Lastůvka sp. n. feeding on Bupleurum gibraltarium in southern Spain, T. chretieni Z. Lastůvka, A. Lastůvka & van Nieukerken sp. n. feeding on Bupleurum rigidum in southern France, Spain and Portugal, and T. siciliae Z. Lastůvka, A. Lastůvka & van Nieukerken sp. n. feeding on B. fruticosum in Sicily. The group is restricted to southwestern Europe and northern Africa, the area where most shrubby Bupleurum species occur. A NJ and Bayesian analysis of DNA barcodes of four out of five species suggest a single origin of Bupleurum feeding in the subgenus Glaucolepis.

Phylogeny and host-plant relationships of the Australian Myrtaceae leafmining moth genus Pectinivalva (Lepidoptera, Nepticulidae), with new subgenera and species

Abstract: The phylogeny of the mainly Australian nepticulid genus Pectinivalva Scoble, 1983 is investigated on the basis of morphology, and a division into three monophyletic subgenera is proposed on the basis of these results. These subgenera (Pectinivalva, Casanovula Hoare, subgen. n. and Menurella Hoare, subgen. n. ) are described and diagnosed, the described species of Pectinivalva are assigned to them, and representative new species are described in each: P. (P.) mystaconota Hoare, sp. n., P. (C.) brevipalpa Hoare, sp. n., P. (C.) minotaurus Hoare, sp. n., P. (M.) scotodes Hoare, sp. n., P. (M.) acmenae Hoare, sp. n., P. (M.) xena- delpha Van Nieukerken & Hoare, sp. n., P. (M.) quintiniae Hoare & Van Nieukerken, sp. n., and P. (M.) tribulatrix Van Nieukerken & Hoare, sp. n. Pectinivalva (Menurella) quintiniae (from Quintinia verdonii, Paracryphiaceae) is the first known member of the genus with a host-plant not belonging to Myrtaceae. P. (M.) xenadelpha from Mt Gunung Lumut, Kalimantan, Borneo, is the first pectinivalvine reported from outside Australia. Keys to the subgenera of Nepticulidae known from Australia, based on adults, male and female genitalia, and larvae, are presented. Host-plant relationships of Pectinivalva are discussed with relation to the phylogeny, and a list of known host-plants of Pectinivalva, including hosts of undescribed species, is presented. DNA barcodes are provided for most of the new and several unnamed species.

Lock, stock and two different barrels: comparing the genetic composition of morphotypes of the Indo-Pacific sponge Xestospongia testudinaria

Abstract: The giant barrel sponge Xestospongia testudinaria is an ecologically important species that is widely distributed across the Indo-Pacific. Little is known, however, about the precise biogeographic distribution and the amount of morphological and genetic variation in this species. Here we provide the first detailed, fine-scaled (<200 km2) study of the morphological and genetic composition of X. testudinaria around Lembeh Island, Indonesia. Two mitochondrial (CO1 and ATP6 genes) and one nuclear (ATP synthase s intron) DNA markers were used to assess genetic variation. We identified four distinct morphotypes of X. testudinaria around Lembeh Island. These morphotypes were genetically differentiated with both mitochondrial and nuclear markers. Our results indicate that giant barrel sponges around Lembeh Island, which were all morphologically identified as X. testudinaria, consist of at least two different lineages that appear to be reproductively isolated. The first lineage is represented by individuals with a digitate surface area, CO1 haplotype C5, and is most abundant around the harbor area of Bitung city. The second lineage is represented by individuals with a predominantly smooth surface area, CO1 haplotype C1 and can be found all around Lembeh Island, though to a lesser extent around the harbor of Bitung city. Our findings of two additional unique genetic lineages suggests the presence of an even broader species complex possibly containing more than two reproductively isolated species. The existence of X. testudinaria as a species complex is a surprising result given the size, abundance and conspicuousness of the sponge.

The role of a proto-Schelde River in the genesis of the southwestern Netherlands, inferred from the Quaternary successions and fossils in Moriaanshoofd Borehole (Zeeland, the Netherlands)

Abstract: We investigated the Quaternary lithological succession and faunas in a borehole near Moriaanshoofd (Province of Zeeland, SW Netherlands), in order to improve our understanding of the depositional context of classical Gelasian mammal faunas from the region. The fossils mostly derive from the base of a fossil-rich interval between 31 m and 36.5 m below the surface, that was initially interpreted as a Middle or Late Pleistocene interglacial marine unit, but turned out to be a Late Quaternary fluvial unit with large amounts of reworked fossils and sediments. Eocene mollusc taxa pinpoint Flanders (Belgium) as the source region for this river. Within the base of this paleo-Schelde River fossil material of various stratigraphic provenance became incorporated.

Bathyal and abyssal Pectinoidea from the Red Sea and Gulf of Aden (Bivalvia: Propeamussiidae, Entoliidae, Pectinidae)

Abstract: Sixteen species of Pectinoidea (12 Propeamussiidae, 1 Entoliidae and 3 Pectinidae), collected during several expeditions to the Red Sea and Gulf of Aden are listed, with notes on geographical and bathymetrical distributions, nomenclature and taxonomy. Three propeamussiid species are new to science: Propeamussium arabicum, Cyclopecten erythraeensis, Cyclopecten meteorae, and two pectinoid species are new records for the Red Sea: Parvamussium scitulum (Propeamussiidae), Pectinella aequoris (Entoliidae). Lectotypes are selected for P. steindachneri (sturany) and P. siebenrocki (sturany).