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1.
Nine new species of carnivorous sponges, namely Cladorhiza segonzaci , Chondrocladia koltuni , Chondrocladia lampadiglobus , Asbestopluma agglutinans , Asbestopluma ( Helophloeina ) formosa , Abyssocladia huitzilopochtli , Abyssocladia inflata , Abyssocladia dominalba and Abyssocladia naudur , are described. The subgenus Helophloeina Topsent, 1929 and the genus Abyssocladia Lévi, 1964 are revived and redefined, with an identification key for Abyssocladia which at present includes seven species. Eight of the sponges were collected from the French IFREMER manned submersible Nautile near active hydrothermal sites of the East Pacific Rise and of the North Fiji and Lau Basins, one from the Russian submersible Mir 2 in the Northwest Pacific near Bering Island, and one from the US submersible Alvin south of Easter Island. Their life conditions are described from direct observations from the submersibles. Some remarks are presented on the taxonomy of Cladorhizidae and more generally of carnivorous Poecilosclerida. The study suggests a very high degree of diversity in the deep Pacific carnivorous sponges.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 148 , 553–584.  相似文献   

2.
Alopoglossidae is a family of Neotropical lizards composed of 23 species allocated in two genera (Alopoglossus and Ptychoglossus). There is a lack of knowledge about the phylogenetic relationships and systematics of this family. Published phylogenies that include alopoglossid species have very low taxon coverage within the family, and are usually based on limited character sampling. Considering these shortcomings, we infer the phylogenetic relationships of Alopoglossidae—including all but one species in the family—based on the combined analyses of DNA sequences and morphological characters. We use four loci (the mitochondrial 12S, 16S and ND4; the nuclear C-mos) and a matrix of 143 phenotypic characters from scutellation, tongue morphology, hemipenis morphology, and osteology. The dataset is analyzed with Maximum Parsimony, with four alternative weighting schemes: three under Extended Implied Weighting, and one with equal weighting. The respective resulting topologies are compared in a sensitivity analysis framework. Our analyses support the paraphyly of Ptychoglossus, with Alopoglossus nested within it. We provide an updated classification for the family, where Ptychoglossus Boulenger, 1890 is considered a junior synonym of Alopoglossus Boulenger, 1885.  相似文献   

3.
Sponge species may present several morphotypes, but sponges that are morphologically similar can be separate species. We investigated morphological variation in Mycale laevis, a common Caribbean reef sponge. Four morphotypes of M. laevis have been observed (1) orange, semi-cryptic, (2) orange, massive, (3) white, semi-cryptic, and (4) white, massive. Samples of M. laevis were collected from Key Largo, Florida, the Bahamas Islands, and Bocas del Toro, Panama. Fragments of the 18S and 28S rRNA ribosomal genes were sequenced and subjected to phylogentic analyses together with sequences obtained for 11 other Mycale species and additional sequences retrieved from GenBank. Phylogenetic analyses confirmed that the genus Mycale is monophyletic within the Order Poecilosclerida, although the subgenus Aegogropila is polyphyletic and the subgenus Mycale is paraphyletic. All 4 morphotypes formed a monophyletic group within Mycale, and no genetic differences were observed among them. Spicule lengths did not differ among the 4 morphotypes, but the dominant megasclere in samples collected from Florida and the Bahamas was the strongyle, while those from Panama had subtylostyles. Our data suggest that the 4 morphotypes constitute a single species, but further studies would be necessary to determine whether skeletal variability is due to phentotypic or genotypic plasticity.  相似文献   

4.
5.
In this paper we carry out a taxonomic revision and phylogenetic analysis of the linyphiid spider genus Solenysa Simon, 1894. A total of 12 species is treated here, including five new species collected from China and Japan: Solenysa akihisai Tu sp. nov., Solenysa lanyuensis Tu sp. nov., Solenysa retractilis Tu sp. nov., Solenysa tianmushana Tu sp. nov. , and Solenysa yangmingshana Tu sp. nov. Solenysa circularis Gao, Zhu & Sha, 1993 is a junior synonym of Solenysa protrudens Gao, Zhu & Sha, 1993. We have assembled two different character matrices to reconstruct the phylogenetic relationships of Solenysa. In the first matrix (Matrix 1), five representative species of Solenysa were added to the morphological dataset of Miller & Hormiga to test the monophyly of the genus and its placement within Linyphiidae. The genitalic structures and somatic morphology of Solenysa were studied by means of scanning electron microscopy for the first time. To infer the species‐level phylogenetic relationships of Solenysa we produced a second matrix (Matrix 2) that includes all 12 Solenysa species and six outgroup species chosen from the results of the analysis of the first matrix. The two most parsimonious trees from the analysis of Matrix 1 support the monophyly of Solenysa and its placement within the ‘Distal Erigonines’ clade. The single most parsimonious tree resulting from the analysis of the second matrix suggests that the Solenysa clade includes four monophyletic groups, each group represented by a distinct genitalic pattern. The morphology of Solenysa, both somatic and genitalic, is highly autapomorphic. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 161 , 484–530.  相似文献   

6.
Every large clade of Eukarya has its own pattern of kinetid (flagellar apparatus) structure, which is stable and specific within the group, thereby being a good phylogenetic marker. The kinetid structure of sponge choanocytes might be a candidate for such marker for the phylogeny of Porifera. Kinetids of two heteroscleromorphs, Halichondria sp. (Suberitida) and Crellomima imparidens (Poecilosclerida), have been investigated here for the first time, and a reconstruction of the kinetid for each species is provided. The kinetids of both species comprise a flagellar kinetosome with a nuclear fibrillar root, a basal foot and satellite producing microtubules; a centriole is absent. Good resolution images reveal a new thin structure, the axial granule, in the flagellar transition zone which might be present in other sponges. The comparison of kinetids in investigated sponges revealed three types of kinetid in Demospongiae, and their distribution in the taxon has been shown on a molecular phylogenetic tree. Kinetid characters of the common ancestor of Demospongiae are discussed. J. Morphol. 277:925–934, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   

7.
Therevidae (stilleto flies) are a little-known family of asiloid brachyceran Diptera (Insecta). Separate and combined phylogenetic analyses of 1200 bases of the 28S ribosomal DNA and 1100 bases of elongation factor-1α were used to infer phylogenetic relationships within the family. The position of the enigmatic taxon Apsilocephala Kröber is evaluated in light of the molecular evidence. In all analyses, molecular data strongly support the monophyly of Therevidae, excluding Apsilocephala, and the division of Therevidae into two main clades corresponding to a previous classification of the family into the subfamilies Phycinae and Therevinae. Despite strong support for some relationships within these groups, relationships at the base of the two main clades are weakly supported. Short branch lengths for Australasian clades at the base of the Therevinae may represent a rapid radiation of therevids in Australia.  相似文献   

8.
We investigated microorganisms associated with a deep-sea sponge, Characella sp. (Pachastrellidae) collected at a hydrothermal vent site (686 m depth) in the Sumisu Caldera, Ogasawara Island chain, Japan, and with two sponges, Pachastrella sp. (Pachastrellidae) and an unidentified Poecilosclerida sponge, collected at an oil seep (572 m depth) in the Gulf of Mexico, using polymerase chain reaction–denaturing gradient gel electrophoresis (PCR-DGGE) directed at bacterial 16S rRNA gene sequences. In the PCR-DGGE profiles, we detected a single clearly dominant band in each of the Characella sp. and the unidentified Poecilosclerida sponge. BLAST search of their sequences showed that they were most similar (>99% identity) to those of the gammaproteobacterial thioautotrophic symbionts of deep-sea bivalves from hydrothermal vents, Bathymodiolus spp. Phylogenetic analysis of the near-full length sequences of the 16S rRNA genes cloned from the unidentified Poecilosclerida sponge and Characella sp. confirmed that they were closely related to thioautotrophic symbionts. Although associations between sponges and methanotrophic bacteria have been reported previously, this is the first report of a possible stable association between sponges and thioautotrophic bacteria.  相似文献   

9.
Sequences of chloroplast gene matK and internal transcribed spacers of nuclear ribosomal RNA genes were used for phylogenetic analyses of Aesculus, a genus currently distributed in eastern Asia, eastern and western North America, and southeastern Europe. Phylogenetic relationships inferred from these molecular data are highly correlated with the geographic distributions of species. The identified lineages closely correspond to the five sections previously recognized on the basis of morphology. Ancestral character-state reconstruction, a molecular clock, and fossil evidence were used to infer the origin and biogeographic history of the genus within a phylogenetic framework. Based on the molecular phylogenetic reconstruction of the genus, sequence divergence, and paleontological evidence, we infer that the genus originated during the transition from the Cretaceous to the Tertiary (~65 M.Y.B.P.) at a high latitude in eastern Asia and spread into North America and Europe as an element of the “boreotropical flora”; the current disjunct distribution of the genus resulted from geological and climatic changes during the Tertiary.  相似文献   

10.
Little information on evolutionary relationships of Neotropical organisms or on the factors that have shaped the diversity currently encountered in this region is available. However, it is clear that biotic interactions and abiotic aspects have played important roles for species diversification in the region. This study focuses on Dolichandra (Bignonieae, Bignoniaceae), a clade of Neotropical lianas that is distributed broadly across different habitats and with diverse pollination and dispersal systems. We used sequences from two plastid DNA markers (ndhF and rpl32‐trnL) and one nuclear gene (PepC) to infer phylogenetic relationships in Dolichandra using parsimony and Bayesian approaches. We then used this phylogenetic framework as basis to study the biogeographic history, reconstruct the evolution of morphological characters and test the impact of morphology and environment on the diversification of the genus. More specifically, we: (1) time‐calibrate the phylogenetic tree of Dolichandra; (2) estimate the ancestral areas of the various lineages; (3) estimate the ancestral states of discrete and continuous morphological traits; (4) test for phylogenetic signal in environmental and phenotypic data; and (5) test whether morphological characters and/or niche evolution are correlated with cladogenesis. All Dolichandra spp. are monophyletic in the combined molecular phylogeny; relationships among species are generally well resolved, although poorly supported in some instances. The genus is inferred to have originated 36.43–26.23 Mya, possibly in eastern South America. Ancestral state reconstructions of continuous and discrete floral characters inferred a mixed morphology as the ancestral condition for the group. Phylogenetic signal differed between perianth and sexual whorls and gradual evolution was recovered for all traits except style length and anther length. Environmental variables showed no phylogenetic signal and a pattern of variation that was not correlated with branch length, suggesting that environmental transitions were concomitant with speciation. Dispersal is inferred to be the main driver of the differential distribution observed among species. In addition, climatic preferences and floral characters seem to have been important reproductive barriers in Dolichandra. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 403–420.  相似文献   

11.
12.
In order to infer phylogenetic relationships between tuna species of the genus Thunnus, partial sequences of the mitochondrial cytochrome b and ATPase genes were determined in all eight species. Supplemental restriction analysis on the nuclear rRNA gene was also carried out. Pacific northern bluefin tuna (Thunnus thynnus orientalis) was found to have mtDNA distinct from that of the Atlantic subspecies (T. t. thynnus) but very similar to that from the species albacore (T. alaluga). In contrast, no differentiation in nuclear genome was observed between the Atlantic and Pacific northern bluefin tunas. The Atlantic northern bluefin and southern bluefin tunas possessed mtDNA sequences very similar to species of yellowfin tuna group and not so similar to albacore and bigeye tunas which were morphologically assigned to the bluefin tuna group. The molecular data indicate that (1) mtDNA from albacore has been incorporated into the Pacific population of northern bluefin tuna and has extensively displaced the original mtDNA, and (2) albacore is the earliest offshoot, followed by bigeye tuna in this genus, which is inconsistent with the phylogenetic relationships between these tuna species inferred from morphology. Correspondence to: S. Chow  相似文献   

13.
Yuen-Po Yang  Ho-Yih Liu  Yi-Shan Chao   《Flora》2009,204(9):692-699
The highly specialized trap glands of carnivorous plant are responsible for the digestion and absorption of the prey; however, there are few studies on their systematics and evolution. In this study, the gland morphology of six carnivorous plant species of the genus Utricularia (Lentibulariaceae) in Taiwan, including U. aurea Lour., U. australis R. Br., U. bifida L., U. caerulea L., U. gibba L. and U. striatula Sm., was examined with a scanning electron microscope. The glands on both the outer and inner surfaces of the traps were examined. We found that the external glands had little diagnostic value, but the internal glands could be used in the identification of Taiwan species. Evolutionary trends of gland characteristics are discussed, analyzing morphology of the internal glands, based on previous work. A new hypothesis for the evolution of internal gland structure in Utricularia is also proposed.  相似文献   

14.
The endemic Australian genus Bonjeania Irwin & Lyneborg is revised. Seven species are described as new: B. angelikae sp.n., B. clamosis sp.n., B. dynastis sp.n., B. flavofemoralis sp.n., B. irwinae sp.n., B. orphne sp.n. and B. trilineata sp.n. Three species, B. actuosa (White), B. nitidifrons (Macquart) and B. segnis (White), are redescribed. All species of Bonjeania were compared in a cladistic analysis with Agapophytus albobasalis Mann and five exemplars of the speciose sister genus Parapsilocephala Kröber, and the phylogenetic relationships of Bonjeania discussed. The male genitalic musculature of B. clamosis sp.n. is described and figured, and discussed with respect to previous studies on other Therevidae.  相似文献   

15.
Asbestopluma hypogea (Porifera) is a carnivorous species that belongs to the deep-sea taxon Cladorhizidae but lives in littoral caves and can be raised easily in an aquarium. It passively captures its prey by means of filaments covered with hook-like spicules. Various invertebrate species provided with setae or thin appendages are able to be captured, although minute crustaceans up to 8 mm long are the most suitable prey. Transmission electron microscopy observations have been made during the digestion process. The prey is engulfed in a few hours by the sponge cells, which migrate from the whole body towards the prey and concentrate around it. A primary extracellular digestion possibly involving the activity of sponge cells, autolysis of the prey and bacterial action results in the breaking down of the prey body. Fragments of the prey, including connective cells and muscles, are then phagocytosed and digested by archaeocytes and bacteriocytes. The whole process takes 8–10 days for a large prey. This unique feeding habit implies the capture and digestion of a macro-prey without any digestive cavity. It would appear to be an adaptation to life in deep-sea oligotrophic environments. Carnivorous sponges provide actual evidence, through a functional example, that a transition is possible from the filter-feeder poriferan body plan towards a different organizational plan through loss of the aquiferous system, a transition that has been hypothesized for the early evolution of Metazoa.Electronic Supplementary Material Supplementary material is available in the online version of this article at  相似文献   

16.
The phylogenetic relationships among flesh flies of the family Sarcophagidae has been based mainly on the morphology of male genitalia. However, the male genitalic character-based relationships are far from satisfactory. Therefore, in the present study mitochondrial DNA has been used as marker to unravel genetic relatedness and to construct phylogeny among five sympatric species of the genus Sarcophaga. Two mitochondrial genes viz., cytochrome oxidase subunit 1 (COI) and NAD dehydrogenase subunit 5 (ND5) were sequenced and genetic distance values were calculated on the basis of sequence differences in both the mitochondrial genes. The data revealed very few genetic difference among the five species for the COI and ND5 gene sequences.  相似文献   

17.
Gongora, J., Cuddahee, R. E., do Nascimento, F. F., Palgrave, C. J., Lowden, S., Ho, S. Y. W., Simond, D., Damayanti, C. S., White, D. J., Tay, W. T., Randi, E., Klingel, H., Rodrigues‐Zarate, C. J., Allen, K., Moran, C. & Larson, G. (2011). Rethinking the evolution of extant sub‐Saharan African suids (Suidae, Artiodactyla). —Zoologica Scripta, 40, 327–335. Although African suids have been of scientific interest for over two centuries, their origin, evolution, phylogeography and phylogenetic relationships remain contentious. There has been a long‐running debate concerning the evolution of pigs and hogs (Suidae), particularly regarding the phylogenetic relationships among extant Eurasian and African species of the subfamily Suinae. To investigate these issues, we analysed the mitochondrial and nuclear DNA sequences of extant genera of Suidae from Eurasia and Africa. Molecular phylogenetic analyses revealed that all extant sub‐Saharan African genera form a monophyletic clade separate from Eurasian suid genera, contradicting previous attempts to resolve the Suidae phylogeny. Two major sub‐Saharan African clades were identified, with Hylochoerus and Phacochoerus grouping together as a sister clade to Potamochoerus. In addition, we find that the ancestors of extant African suids may have evolved separately from the ancestors of modern day Sus and Porcula in Eurasia before they colonised Africa. Our results provide a revision of the intergeneric relationships within the family Suidae.  相似文献   

18.
The family Lebachacanthidae was erected for“Orthacanthus” senkenbergianus, a xenacanthiform from the Lower Permian of Lebach (Germany). Recently, the validity of the family has been questioned and the type species,Lebachacanthus senkenbergianus, has been included in the genusOrthacanthus Agassiz 1843, subgenusLebachacanthus Soler-Gijón 1997. Arguments against such changes are presented here. Anew phylogenetic analysis is performed in order to determine the relationships of Lebachacanthidae with the rest of xenacanthiforms.Hagenoselache, a xenacanthiform recently described from the Namurian of Germany, is included in the phylogenetic analysis together with new data on tooth histology. The new phylogenetic analysis confirms Lebachacanthidae as a distinct family within Xenacanthiformes. Lebachacanthidae is the sister group of Xenacanthidae which includes trueOrthacanthus. Hagenoselache is more derived thanDiplodoselache (the most primitive xenacanthiform) and is the sister group of the clade formed by Lebachacanthidae and Xenacanthidae. The phylogenetic position of Lebachacanthidae is consistent with the idea of heterochronic processes in the evolution of the xenacanth sharks. Heterochrony (peramorphic type) can explain morphological clines in dorsal spine morphology from basal xenacanthiforms (Diplodoselachidae) through Lebachacanthidae to the derived Xenacanthidae (comprisingOrthacanthus, Xenacanthus, Triodus andPlicatodus).  相似文献   

19.
20.
The Ortheziidae (ensign scale insects) is a morphologically well‐defined family. The morphology and occurrence in the fossil record suggests a probable early origin of the family in scale insect evolution. The present phylogenetic analysis – based on 69 morphological characters of female ortheziids, using 39 exemplar Recent species – provides the first analytical assessment of relationships among living genera of the family, as well as the relationships of eight fossil species, based on complete, well‐preserved specimens in amber. Monophyly of the subfamilies Newsteadiinae, Ortheziinae and Ortheziolinae is supported, but Nipponortheziinae is found to be paraphyletic by inclusion of the Ortheziolinae. Thus, the subfamily Ortheziolinae is reduced in rank to tribe Ortheziolini stat.n. , which now includes Matileortheziola Kozár & Foldi, Ortheziolacoccus Kozár, Ortheziolamameti Kozár and Ortheziola?ulc. Consequently, the tribes Matileortheziolini, Ortheziolacoccini and Ortheziolamametini are synonymized ( syn.n. ) here under Ortheziolini. Five new species and one new genus of fossil ensign scales are described from three amber deposits: Burmorthezia gen.n. with type species Burmorthezia kotejai sp.n. and also B. insolita sp.n ., both in mid‐Cretaceous Burmese amber (98 Ma) and Arctorthezia baltica sp.n. in Eocene Baltic amber (c. 43 Ma) based on second‐instar nymphs; Mixorthezia kozari sp.n . and M. dominicana sp.n . in Miocene Dominican amber (c. 17 Ma) based on adult females. Fossil placements are unambiguous, with Burmorthezia forming a stem to crown‐group (Recent and Tertiary) Ortheziidae. A summary of described fossil ortheziids is provided.  相似文献   

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