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1.
Lessonia is the main Laminariales found along the southeast Pacific coast. Lessonia nigrescens Bory de Saint‐Vincent in the intertidal and Lessonia trabeculata Villouta et Santelices in the subtidal, are the most important habitat constructors in rocky coastal communities in northern and central Chile. In both species, the seasonal production and erosion of distal tissue were estimated in biomass units using the Area of Constant Biomass Model that combined the individual blade elongation, obtained with the traditional hole‐punching method, with the blade length and biomass distribution along the blade. In austral late spring (December 96) and autumn (May 97), blade production and erosion were transformed to the level of population from standing stock measurements (number and biomass of blades and plants per substrate area), considering that previous blade weight analysis showed the highest and lowest values at these times, as well as the population parameter extremes that were expected to occur. Both species displayed a seasonal pattern, with a production increase in later winter and spring and decrease towards the end of summer that coincided with higher distal tissue erosion. At the level of individual blades, Lessonia trabeculata showed higher mean production (0.026 g dw d−1) and erosion (0.01 g dw d−1) than L. nigrescens (production 0.01 g dw d−1 and loss 0.002 g dw d−1). The standing stocks, with respect to density and biomass, were similar in spring and autumn for both populations. Nevertheless, the net productivity (production minus erosion) of the intertidal L. nigrescens showed greater values due to the greater density of blades (2112 ± 1360 (SE) blades m−2) compared with the subtidal L. trabeculata (527 ± 151 (SE) blades m−2). Spring net productivities of 42 g dw m−2d−1 (254 g ww m−2d−1; 11.46 gC m−2d−1) for L. nigrescens and 11 g dw m−2 d−1 (64 g ww m−2 d−1; 2.46 gC m−2d−1) for L. trabeculata were estimated. A preliminary model of production and biomass fate for Lessonia populations is proposed.  相似文献   

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Five morphologically similar species of Acrapex Hampson (Lepidoptera, Noctuidae, Noctuinae, Apameini), from sub-Saharan Africa are reviewed, including four new species that are described: Acrapex mondogeneta Le Ru n. sp., A. mubale Le Ru n. sp., A. robe Le Ru n. sp. and A. rubona Le Ru n. sp. These five species belong to a species complex that we hereby define as the Acrapex minima group. Host plants of three species are recorded; Acrapex minima is recorded for the first time on a host plant, Digitaria natalensis Stent; A. mondogeneta on Hyparrhenia hirta (L.) Stapf and A. rubona on Imperata cylindrica (L.) P. Beauv. We also conducted molecular phylogenetics (using both Bayesian inference and maximum likelihood) and molecular species delimitation analyses (Poisson tree processes) on a six gene multi-marker dataset (four mitochondrial and two nuclear gene fragments; 4582 nucleotides in length) of 42 specimens and 22 species, including 23 specimens from the Acrapex minima group. The results of the corresponding analyses support the monophyly of the group and the species status of the newly described taxa.  相似文献   

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Species of the Amazonian jumping spider genus Soesiladeepakius Makhan are confirmed as non‐salticoids. Sequences of nuclear (28S, Actin) and mitochondrial (16S through NADH dehydrogenase subunit I, ‘16S‐ND1’) gene regions, analysed under parsimony and maximum likelihood, placed the genus within the lapsiines, closely related to Galianora Maddison. Additionally, six new species of this genus are herein described, namely Soesiladeepakius lyra sp. nov. , Soesiladeepakius retroversus sp. nov. , Soesiladeepakius arthrostylus sp. nov. , Soesiladeepakius gasnieri sp. nov. , Soesiladeepakius biarmatus sp. nov. , and Soesiladeepakius uncinatus sp. nov. , all from the Amazon region in Brazil. To test the monophyly of Soesiladeepakius within lapsiines, a cladistic analysis was carried out using a data matrix comprising 24 morphological characters scored for 12 taxa. The analysis resulted in two equally parsimonious trees of 29 steps. One of these trees is used to discuss the relationships among the species of Soesiladeepakius and character evolution. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 274–295.  相似文献   

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Twelve morphologically similar species of Acrapex Hampson 1894, (Lepidoptera, Noctuidae, Noctuinae, Apameini, Sesamiina), from Western, Central and Eastern Africa are reviewed. Eight of these species are new to science and are described: Acrapex akunamatata n. sp. and A. incrassata n. sp. from Kenya; A. gracilis n. sp., A. iringa n. sp., A. lukumbura n. sp. and A. rungwe n. sp. from Tanzania; A. soyema n. sp. from Ethiopia; and A. zoutoi n. sp. from Benin. All 12 species belong to a species complex that we hereby define as the Acrapex apicestriata group. Host-plants for three of the new species are recorded: Setaria incrassata (Hochst.) Hack. for Acrapex incrassata; Cymbopogon pospishilii (K. Schum.) C.E. Hubb. for A. rungwe; and Andropogon perligulatus Stapf. for A. zoutoi. We also conducted molecular phylogenetic analyses (using maximum likelihood and Bayesian inference) on a six gene multimarker molecular dataset (four mitochondrial and two nuclear gene fragments; 4581 nucleotides in length) consisting of 15 Acrapex species (including seven species from the apicestriata group) and four outgroups species from the subtribe Sesamiina (from genera Busseola Thurau 1904, Sciomesa Tams & Bowden 1953, Pirateolea Moyal, Le Ru, Conlong, Cugala, Defabachew, Matama-Kauma, Pallangyo & Van den Berg 2010 and Sesamia Boisduval & Guenée 1852). Both maximum likelihood and Bayesian inference analyses yield a similar and well-supported topology, which supports the monophyly of the apicestriata group.  相似文献   

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The phylogenetic relationships amongst the Arminidae were analysed based upon morphological characters of 58 presently described species or nudibranchs, including 35 previously described Arminidae and 20 new species of Dermatobranchus. From the literature review and anatomical examinations, 43 characters were considered for 78 taxa. These characters were polarized using Berthella canariensis as the outgroup taxon and the type species of several other genera identified from recent publications. The resulting phylogeny supports the monophyly of Arminidae, Dermatobranchus, Doridina, and Proctonotidae. The paraphyly of the Arminina is further demonstrated in this study. Two previously described, but poorly known, species of Indo-Pacific Armina are redescribed, Armina magnaBaba, 1955 and Armina paucifoliataBaba, 1955. The anatomy and taxonomic status of nine previously described species of Dermatobranchus were examined in this study. The anatomy of Dermatobranchus pustulosus (van Hasselt, 1824) has been overlooked since Bergh (1888) illustrated the radula of van Hasselt's specimen. It is redescribed and its range is extended to several new localities in the western Pacific. Dermatobranchus pulcherrimus Miller & Willan, 1986 is considered here as a new synonym of Dermatobranchus rubidus (Gould, 1852). The following 20 species of Dermatobranchus are new and are described in the present paper: Dermatobranchus albineus sp. nov., Dermatobranchus arminus sp. nov., Dermatobranchus caesitius sp. nov., Dermatobranchus caeruleomaculatus sp. nov., Dermatobranchus cymatilis sp. nov., Dermatobranchus dendonephthyphagus sp. nov., Dermatobranchus diagonalis sp. nov., Dermatobranchus earlei sp. nov., Dermatobranchus fasciatus sp. nov., Dermatobranchus funiculus sp. nov., Dermatobranchus kalyptos sp. nov., Dermatobranchus kokonas sp. nov., Dermatobranchus leoni sp. nov., Dermatobranchus microphallus sp. nov., Dermatobranchus oculus sp. nov., Dermatobranchus phyllodes sp. nov., Dermatobranchus piperoides sp. nov., Dermatobranchus rodmani sp. nov., Dermatobranchus semilunus sp. nov., and Dermatobranchus tuberculatus sp. nov. Eighteen of these new taxa are found in the Indo-Pacific tropics and two are found in temperate South Africa, D. albineus and D. arminus. Unique combinations of morphological characters distinguish these as new species of Dermatobranchus. Several species that are externally similar have radically divergent internal morphology, are members of different clades of Dermatobranchus, and represent cryptic species. Especially important is the radular morphology, which shows remarkable diversity of form, probably related directly to the diversification of feeding of members of this clade on various octocorals.  相似文献   

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The taxonomy of common northern nudibranch molluscs of the genus Dendronotus in the vast cold regions of Eurasia remains largely unknown. Abundant material collected in many localities from the Barents Sea, via the Arctic region, to the north‐west Pacific was analysed for the first time. An integrated approach combining morphological and ontogenetic data with molecular four‐gene (COI, 16S, H3, and 28S) analysis reveals seven species, including three previously undescribed. Dendronotus frondosus (Ascanius, 1774) and Dendronotus dalli Bergh, 1879 were commonly considered as amphiboreal species; however, according to this study they are restricted to the North Atlantic and the North Pacific, respectively. In the north‐west Pacific two new species were discovered, D endronotus kamchaticus sp. nov. and D endronotus kalikal sp. nov. , that are externally similar to D. frondosus, but that show significant distance according to molecular analysis and are considerably different in radular morphology. In the North Atlantic a new species D endronotus niveus sp. nov. , sibling to North Pacific D. dalli, is revealed. The separate status of North Atlantic Dendronotus lacteus (Thompson, 1840) is confirmed, including considerable range extension. The essential similarity of early ontogenetic stages of radular development common for species with disparate adult radular morphology (such as D. frondosus and D. dalli) is shown, and its importance for taxonomy is discussed. © 2015 The Linnean Society of London  相似文献   

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Kotov  Alexey A.  Dumont  Henri J. 《Hydrobiologia》2000,428(1):85-113
We studied the morphology and variability of Ilyocryptus spinifer Herrick, 1882 from different parts of the world using optical microscopy and SEM, re-examining type material wherever possible. Morphometric analysis failed to reveal significant regional differences between populations. The following species names for members of Ilyocryptus spinifer group, I. halyi Brady, 1886; I. longiremis Sars, 1888; I. immundus F. Mueller in Ihering, 1895; I. verrucosus Daday, 1905; and I. tetraspinatus Berganim, 1939, are junior synonyms of I. spinifer. A new species from this group is described from Queensland, Australia. Ilyocryptus timmsi n. sp. shows unique morphological characters in the armature of the lateral swimming setae of the antennal endopod, its apical segment and the postabdominal claws.  相似文献   

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A very diverse ciliate community was found in nine soil samples from the Shimba Hills Nature Reserve in Kenya, equatorial Africa. The ciliates, respectively, their resting cysts, were re-activated from air-dried samples using the non-flooded Petri dish method. Species were determined from life and by silver impregnation. 34 (27%) of the 125 taxa identified had not yet been described in 1985, when the samples were collected and investigated. The richest samples, each containing 59 species, were those from a deciduous primary forest and a young secondary pine forest. The most remarkable species discovered in the Shimba Hills were Krassniggia auxiliaris, Bresslauides terricola, Gigantothrix herzogi, and Afrothrix darbyshirei. They are flagships with a very distinct morphology and easy to recognise due to their extraordinarily large body size. Krassniggia auxiliaris occurs also in Australia and probably has a restricted Gondwanan distribution, like some other ciliates. Bresslauides terricola was later found in soils from all main biogeographical regions, except for Antarctica. Gigantothrix herzogi and Afrothrix darbyshirei are still unique to the Shimba Hills. The following taxa are described in detail: Sikorops woronowiczae nov. gen., nov. spec., Arcuospathidium multinucleatum nov. spec., Dileptus similis Foissner, 1995, Plagiocampa bitricha nov. spec., Drepanomonas exigua exigua Penard, 1922, D. exigua bidentata nov. sspec., Parafurgasonia protectissima (Penard, 1922) nov. comb., P. terricola nov. spec., Brachyosoma brachypoda mucosa nov. sspec., Gigantothrix herzogi nov. gen., nov. spec., Afrothrix darbyshirei nov. gen., nov. spec., Oxytricha africana nov. spec., and O. elegans nov. spec.  相似文献   

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Most nominal fan worm species belonging to the genus Parasabella Bush, 1905, and Sabellomma Nogueira, Fitzhugh & Silva‐Rossi, 2010 (Sabellidae, Annelida) lack unique morphological diagnostic features. Species diagnoses rely on a combination of attributes, often making reference to characters that are qualitatively or quantitatively continuous. This, together with a lack of knowledge about phenotypic intraspecific variation in most species, suggests that the sole use of morphological features is insufficient to identify and characterize some of these species. Examination of collections revealed that Parasabella is a common and diverse group of sabellids along the Australian coastline, although it had only been recorded here twice. The genus Sabellomma is here reported in Australia for the first time. Comparison of morphological data and nuclear (internal transcribed spacer) and mitochondrial (cytochrome oxidase I) DNA sequence data of 30 terminals in a range of analyses allowed us to assess the monophyly of Parasabella and its sister‐group relationship with Sabellomma and to examine some of the species boundaries and genetic diversity within lineages. The combined sequence data results indicate the presence of seven distinct genetic Parasabella lineages in Australia, four of which are assigned to previously described species (three are new records for Australia), and two are considered as a complex of species sharing a unique combination of characters, one of which is described as new. Another Parasabella species with distinct atypical radiolar eyes and a species of Sabellomma are also described as new. © 2015 The Linnean Society of London  相似文献   

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The presence of males in species of Echiniscus has been reported only as recently as 1987 and is still considered to be rare. However, males have been found to be common in a disproportionately large number of species of this genus found in Australia. Evidence of sexual dimorphism is presented for five species (three of which are new to science), females and males of which are differentiated on the basis of distinctive gonopores. In all five species males are shorter with longer clavae. Males of Echiniscus jamesi sp. nov., Echiniscus rodnae sp. nov. and Echiniscus curiosus sp. nov. have significantly longer claws. In E. rodnae sp. nov. and E. curiosus sp. nov. males have significantly longer lateral trunk appendages and the dorsal trunk appendage combinations of males of the latter are different from those of females. The widespread distribution of bisexual species of Echiniscus in xeric habitats in Australia does not support the current theory that parthenogenetic species are favoured in such environments.  相似文献   

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Benthic cyanobacterial mats (BCMs) are natural phenomena in marine environments. Reports of BCMs occurring across coastal marine environments have increased, partly driven by nutrient loading and climate change; thus, there is a need to understand the diversity involved in the proliferations and potential toxicity of the BCMs. Furthermore, marine cyanobacterial mats are observed growing on and affecting the health of corals with one specific cyanobacterial genus, Roseofilum, dominating the microbial mats associated with black band disease (BBD), a destructive polymicrobial disease that affects corals. To explore the diversity of Roseofilum, cyanobacterial mats from various marine habitats were sampled, and individual isolates were identified based on morphology, 16S rRNA gene phylogenies, 16S–23S ITS rRNA region sequence dissimilarities, and phylogenomics. Four novel species of Roseofilum were isolated from benthic marine mats, three from the coasts of Florida, United States (R. capinflatum sp. nov., R. casamattae sp. nov., and R. acuticapitatum sp. nov.) and one from the coast of France (R. halophilum sp. nov.). Our analyses revealed that Roseofilum associated with coral BBD and those not associated with corals but rather from coastal benthic mats are systematically distinct based on both phylogenetic and phylogenomic analyses. Enzyme-linked immunosorbent assay (ELISA) and LC–MS data indicated that microcystin production was found in one of the four species.  相似文献   

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The Neotropical characid fishes of the genus Chalceus Cuvier, 1817, are reviewed. In total, five species are recognized (including three new species). Chalceus epakros sp. nov. is the most widespread geographically, occurring in many rivers of the Amazon basin, the Río Orinoco and in the Essequibo River drainage in Guyana. Chalceus guaporensis sp. nov. is restricted to the upper Rio Madeira, Rio Guaporé and Río Madre de Dios, of Brazil, Bolivia and Peru, respectively. Chalceus spilogyros sp. nov. occurs only in the Rio Trombetas, lower Rio Tapajós and lower Rio Madeira drainages. Chalceus macrolepidotus Cuvier occurs in the Rio Negro drainage, middle and lower Río Orinoco basin and in the rivers of the Atlantic slopes of the Guianas, and Chalceus erythrurus Cope in the Rio Amazonas and Rio Solimões to Río Ucayali drainage in Peru. Chalceus ararapeera Cuvier & Valenciennes and Creagrutus pellegrini Puyo are considered synonyms of C. macrolepidotus , and Pellegrinina heterolepis Fowler is placed into the synonymy of C. erythrurus . Characters pertaining to the monophyly of Chalceus are discussed and a key to species is presented.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 103−135.  相似文献   

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