Syllidae (Polychaeta) from Thalassia testudinum beds at Morrocoy National Park (Venezuela)

A total of 40 species of syllids (Polychaeta: Syllidae) inhabiting Thalassia testudinum beds in Morrocoy National Park, Venezuela, belonging to 13 genera, are reported; 36 species are new for Venezuela: Branchiosyllis exilis, B. oculata, Eusyllis lamelligera, Exogone arenosa, E. breviantennata, E. naidinoides, E. naidina, E. parahomoseta mediterranea, Grubeosyllis clavata, G. heterocirra, Odontosyllis detecta, O. enopla, O. gibba, Opisthosyllis brunnea, Plakosyllis brevipes, Sphaerosyllis bilobata, S. glandulata, S. magnidentata, S. piriferopsis, S. riseri, S. longilamina, S. taylori, Syllis alosae, Syllis riojai, n. comb., S. beneliahui, S. broomensis, S. cornuta, S. corallicola, S. garciai, S. hyalina, S. lutea, S. mexicana, S. prolifera, S. sardai and Xenosyllis scabra.     

Syllinae (Syllidae: Polychaeta) of the Parque Nacional de Coiba, Panama]

Four expeditions were made to Coiba National Park between 1996 and 1998 to characterize this part of the poorly known Panamian Pacific polychaete fauna. The samples were collected by SCUBA diving, either by removing 4 kg blocks of dead coral (Pocillopora sp.) or scraping off 25 x 25 cm quadrats of Telesto multiflora or algae (Dyctiota cf. flavellata, Padina cf. durvillaei and another currently unidentified species). This paper deals with the Syllinae from hard substrates. Twenty-two species belonging to six genera of the subfamily Syllinae Grube, 1850 (Syllidae: Polychaeta) are reported. A new species, Syllis castroviejoi, is described. Four species are newly reported for the Eastern Pacific: Syllis beneliahuae (Campoy & Alquézar, 1982), S. botosaneanui (Hartmann-Schr?der, 1973), S. corallicola Verrill, 1900 and S. garciai (Campoy, 1982), and, likewise, two species are first reports for the Central American Pacific coast: Branchiosyllis pacifica Rioja, 1941 and Syllis truncata Haswell, 1920. Two species, Syllis magna (Westheide, 1974) and S. pigmentata (Chamberlin, 1919), are newly reported for Panama.     

Infrastructural study of photoreceptor organs in the larvae of two Syllidae (Annelida, Polycheta)

The ultrastructure of the larval eyes of two Syllidae: Syllis amica (subfamily: Syllinae) and Odontosyllis ctenostoma (subfamily: Eusyllinae) were studied. These eyes are composed of a pigmented supportive cell and one or two sensory cells. A dense body, corresponding to a secreted lens, can be observed in the ocular cavity formed by the supportive cell. Such a structure present in O. ctenostoma adult eyes has never been described in S. amica adult eyes.     

Phylogeny of Syllidae (Polychaeta) based on morphological data

The phylogeny of Syllidae is assessed in two parsimony analyses of 107 morphological characters. The first analysis included one species of each of the 71 genera of the Syllidae, as well as members of other close families. In the second analysis, 23 poorly known genera were excluded. Character information is based on the examination of available types, additional non-types and newly collected material. Syllidae, except Bollandia Glasby, 1994 is monophyletic. Both analyses supported three of the four traditional subfamilies (Exogoninae, Syllinae and Autolytinae) as monophyletic, whereas Eusyllinae was clearly a polyphyletic group. The genera Anoplosyllis Claparède, 1868, Astreptosyllis Kudenov & Dorsey, 1982 , Streptosyllis Webster & Benedict, 1884, Streptospinigera Kudenov, 1983 and Syllides Örsted, 1845 comprise a well-supported monophyletic group, which we classified as a new subfamily: Anoplosyllinae n. subfam. Our results indicated high levels of homoplasy in the morphological characteristics that traditionally used to differentiate groups, such as the fusion of palps and the presence of nuchal epaulettes. Considering the reproductive modes, schizogamy has appeared twice in the family as the derived condition evolving from epigamy, and Exogoninae may be divided into two monophyletic groups based on the brood system.     

Systematics and evolution of syllids (Annelida,Syllidae)

A large, combined phylogenetic analysis (including morphological and molecular data from 18S rDNA, 16S rDNA and cytochrome c oxidase subunit I), with the highest number of species and genera of Syllidae studied to date (213 terminals), is examined. The data were explored with different parameters and optimality criteria (parsimony, likelihood, and bayesian inference). The monophyly of Syllidae and most of the traditional subfamilies is supported. The subfamily Eusyllinae is polyphyletic, as currently delineated, but it is herein reorganized and its diagnosis modified to be a valid group. Additional well supported clades arise. The phylogenetic relationships of the well known and established genera, as well as several enigmatic genera (e.g. Anguillosyllis, Paraopisthosyllis and Parahaplosyllis), the position of which in syllid taxonomy was uncertain or dubious to date, are clarified. The results corroborate previous hypotheses about the evolution of the reproductive and brooding modes. Within Syllinae, the nature of the stolon is phylogenetically informative. The classification of the whole family is revised and discussed on the basis of this phylogenetic hypothesis. © The Willi Hennig Society 2011.     

Indo-Pacific Syllidae (Annelida,Phyllodocida) share an evolutionary history

The geographic distribution of three intriguing genera of Syllidae (Annelida, Phyllodocida), Alcyonosyllis, Paraopisthosyllis and Megasyllis, is restricted to the Pacific Ocean, Indian Ocean and the Red Sea. In this study new material of several species in all three genera is identified, and the distributions of the species and genera refined; four species of Alcyonosyllis were found to have increased ranges. Additionally, one new species of Paraopisthosyllis is described. Paraopisthosyllis pardus sp. nov. is characterized by having long bidentate bladed-chaetae, segments covered by small papillae, and a colour pattern consisting in dark red-brown antennae and dorsal cirri and several transversal dark red-brown lines per segment. The three genera share several striking morphological characteristics, such as alternation in the arrangement of dorsal cirri, wide segments with secondary annuli and bright, contrasting colour patterns. Alcyonosyllis species are found in association with other organisms, most noticeably anthozoans, whereas members of Paraopisthosyllis and Megasyllis are free living. Molecular information (sequences of DNA) from Alcyonosyllis species (including the type species, A. phili), and the type of Megasyllis (M. corruscans) is included herein for the first time in a phylogenetic analysis. A phylogenetic analysis performed through different methods (Maximum parsimony and Maximum likelihood) using sequences of three genes (18S, 16S and COI) reveals that all the three genera form a monophyletic group within Syllidae, with several synapomorphies, and a common ancestor probably from the Indo-Pacific. Their geographic distribution pattern, the relationships between these genera and the rest of syllids, and the symbiosis in Alcyonosyllis are discussed.     

Autolytinae, Eusyllinae an Exogoninae (Syllidae: Polychaeta) from Coiba National Park, Panama)

This is the second paper on the Syllidae (Polychaeta) from hard substrata of the Coiba National Park (Pacific coast of Panama) (the first paper treated Syllinae). On this second paper nineteen species belonging to eleven genera of the subfamilies Autolytinae, Eusyllinae and Exogoninae (Syllidae: Polychaeta) are reported. The samples were collected by SCUBA diving, either by removing 4 kg blocks of dead coral (Pocillopora spp.) or scraping off 25 x 25 cm quadrats of Telesto multiflora or algae (Dyctiota cf. flavellata, Padina cf. durvillaei and another currently unidentified species). They were collected during four expeditions carried out between 1996 and 1998. Four species are newly reported for the Eastern Pacific: Eusyllis lamelligera Marion & Bobretzky, 1875, Exogone exmouthensis Hartmann-Schr?der, 1980, Proceraea cf. cornuta (Agassiz, 1863) and Sphaerosyllis (S.) magnidentata Perkins, 1981. Ten species are reported for the first time from the Central America Pacific coast: Amblyosyllis cf. granosa Ehlers, 1897 (sensu Westheide 1974), Amblyosyllis speciosa Izuka, 1912, Autolytus multidenticulatus Westheide, 1974, Exogone naidinoides Westheide, 1974, Grubeosyllis concinna (Westheide, 1974), Odontosyllis fulgurans (Audouin & Milne Edward, 1833), Opisthodonta mitchelli Kudenov & Harris, 1995, Pionosyllis articulata Kudenov & Harris, 1995, Sphaerosyllis (S.) californiensis Hartman, 1966 and Syllides cf. reishi Dorsey, 1978. The family Syllidae is represented in the Coiba National Park by 14% of cosmopolitan species, 14% of circumtropical species, 22% of Atlantic and Pacific species and 25% of Pacific species restricted to warm waters. In samples of dead coral the dominant species are S. armillaris (Muller, 1771) and S. gracilis (Campoy, 1982); in samples of telestaceans Grubeosyllis concinna dominates.     

A new species of Carabodes (Acariformes: Carabodidae) from Venezuela

A new species, Carabodes venezolanus is described from Venezuela. A comparison with related species and genera is done.     

Sperm ultrastructure of three Syllinae (Annelida, Phyllodocida) species with considerations on syllid phylogeny and Syllis vittata reproductive biology

Phylogeny of Syllidae is under debate due to new studies based on molecular and morphological data. The noticeable taxonomic diversity of syllids (about 700 listed species) is also mirrored in the array of reproductive strategies as well as in sperm morphology, counting a display of forms already supposed to reflect phylogenetic relationships between the species. The sperm ultrastructure of Syllis gerlachi, S. prolifera and S. vittata is herein presented and compared to the Syllinae species studied previously. Moreover, the egg structure and the gamete allocation within stolons of S. vittata are particularly investigated. Both male germinal cells at different level of maturation and oocytes were found in the same individual of S. vittata, suggesting simultaneous hermaphroditism. The ultrastructural analysis revealed that the observed spermatozoa belong to the ect-aquasperm type resembling those of the similar studied species (Syllis sp., S. pigmentata and S. krohni). Differences in the acrosome structure and nucleus shape are in accordance with a recent phylogenetic reconstruction and suggest a trend in the evolution of spermatozoa in Syllinae toward the development of the apical part. However, further molecular and ultrastructural analyses are needed to support this hypothesis. This is the first record of simultaneous hermaphroditism within Syllinae.     

Index of the Venezuelan marine microflora: diatoms, dinoflagellates and cocolithophorids

The marine phytoplankton of Venezuela has been studied on a regular basis since the mid 20th century. However, a species checklist that can be used as a framework for taxonomic studies is lacking. In this paper, an index of the marine microflora of Venezuela is presented for the first time. The index includes only those diatoms (89 centric and 186 pennate species), dinoflagellates (eight naked and 154 thecate species) and coccolithophores (24 species) for which formal diagnosis and illustrations (drawings and/or photographs) have been reported in the scientific literature (journals and/or first degree or master's theses). It is ordered alphabetically according to class, order, family, and species. It includes the author (s) of the taxa.     

金粟兰科的起源,演化及其分布

本文利用形态解剖,孢粉学及化石资料,讨论了金粟兰科的系统;并对其起源,演化和现代分布格局形成等问题做了合理推测,主要结果如下：（１）Ｓａｒｃａｎｄｒａ和Ｃｈｌｏｒａｎｔｈｕｓ的亲缘关系最接近,而Ａｓｃａｒｉｎａ和Ｈｅｄｙｏｓｍｕｍ的系统位置最靠近。Ｓａｒｃａｎｄｒａ是金粟兰科中最原始的属,而Ｈｅｄｙｏｓｍｕｍ则是最进化的属。（２）金粟兰科可能于白垩纪最早期起源于木质部无导管的,具简单两性虫媒花的祖     

A New Polystiliferous Hoplonemertean, Curranemertes natans gen. et sp.n., from the Caribbean Sea (Nemertina, Polystilifera Reptantia)

A polystiliferous hoplonemertean, Curranemertes natans gen. et sp.n., is described from Venezuela where it was found on corals in shallow water. It is the third species of reptantic Polystilifera known from the Caribbean Sea. Anatomically the new species shows affinities to the genera Punnettia, Polyschista , and Drepanophorina , but because of differences in the nervous system, cerebral organs, and alimentary tract, a new genus is proposed for it.     

Itysa and Lethia, two new genera of neotropical Iridaceae

The new genera Itysa and Lethia , of the Iridaceae, are proposed; the former with two species, I. gardneri (Bak.) Rav., from northeastern Brazil, and I. venezolensis Rav., from Venezuela, the former based on Calydorea gardneri Baker, the latter described as new. Lethia is based on Herbertia umbellata Klatt.     

Compositae of the Guayana Highland—IV. A new species of pentacalia (Senecioneae) from Cerro de la Neblina,Venezuela

Described and illustrated from Cerro de la Neblina in T. F. Amazonas, Venezuela is the fifth known Guayanan species ofPentacalia, a genus recently reinstated from synonymy withinSenecio. The distinctions between these two genera are briefly discussed as are the distinctions betweenPentacalia and similar genera. A key to the new species,Pentacalia neblinesis, and the other species ofPentacalia from the Guayana Highland is given.     

Revisions of Pterogastra and Schwackaea (Melastomataceae: Melastomeae)

The closely related neotropical melastomean genera Pterogastra and Schwackaea are revised, the species illustrated, and their distribution mapped. Schwackaea is maintained as a monotypic genus because it is readily distinguished from all other melastomes by its 8-winged capsule. This weedy little plant occurs from Mexico throughout Central America, chiefly on the Pacific slope, to northern Colombia and on Cocos Island and grows in natural or man-made savannas from sealevel to 2000 m altitude. Two species are recognized in Pterogastra and one new combination, P. divaricata spp. glabra , is made. Pterogastra is characterized by distinctly 4- or 5-winged capsules, unlike those of Schwackaea or any other New World melastome. The more widespread species occurs in Colombia, Venezuela, Guyana, Ecuador, and Peru at altitudes between sealevel and 2600 m in natural or disturbed grasslands. The second species is endemic in southwestern Venezuela and is confined to natural savannas at low altitudes.     

Neogene biofacies in eastern Venezuela and their calibration with seismic data

A detailed micropaleontologic study of Miocene foraminifers was made in order to integrate the seismic and biostratigraphic information in the Maturín sub-basin, eastern Venezuela. The sequence studied involves the Freites, Oficina, and Carapita Formations: The Freites and Oficina Formations are characterized by interbedded shale, siltstone, and sandstone. However, the Carapita Formation is formed mainly by shale and occasional thin sandstone beds, which sometimes represent turbiditic deposits.Analysis of existing biostratigraphic information from several wells and the recent exploration in the area, serve as a basis for distinguishing the faunal assemblages and their distribution and faunal variations, as well as, for determining chronological and paleobathymetric changes in the sequence studied.Towards the northeast, biofacies are useful for correlation throughout the area. These assemblages contain a higher diversity and abundance of calcareous forms, plus deep-water agglutinated foraminifers, typical of normal marine outer-neritic to bathyal conditions. To the southwest, however, we found shallow biofacies which are represented mainly by agglutinated genera and lower values for the abundance and diversity of calcareous specimens, especially planktic species. These parameters suggest the existence of water masses with low-oxygen content and large amounts of terrigenous and organic material in suspension.Biofacies and paleobathymetric data from each of the wells were compared with regional seismic lines to interpret changes from platform to slope water depths within the area.Analysis of species associations in the Miocene strata of the Maturín sub-basin, Venezuela, established a faunal variation that demonstrates a deepening trend from southwest to northeast.