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1.
Two new trochids of the genus Antimargarita, A. powelli and A. bentarti, from the Antarctic waters are described here. A. powelli, from the Bellingshausen Sea, is distinguished by its rounded whorls, numerous spiral cords, a radula with seven lateral
teeth at each side of the rachidian, and an epipodium with eight pairs of tentacles. A. bentarti, from the South Shetland Islands, is characterized by having a shell outline gradated by prominent primary spiral cords,
a radula with five lateral teeth at each side of the rachidian and an epipodium with six tentacles on the left side. The diagnostic
features for Antimargarita are redefined considering both shell and anatomical features and its suprageneric placement is discussed. 相似文献
2.
The diet of the Weddell seal Leptonychotes weddellii at the South Orkney Islands was investigated by the analysis of 44 and 26 faecal samples collected from the beaches of Laurie
Island from May 1999 to January 2000 and from October to December 2001, respectively. The diet was diverse and both pelagic
and benthic-demersal organisms were represented in the samples. Fish were the most frequent prey of the samples in both seasons,
and fish and krill were the most numerous prey items. Octopods predominated by mass in 1999, whereas krill constituted the
bulk of the diet in 2001, a fact that was not observed previously. Among fish, Gobionotothen gibberifrons was largely the species that contributed mostly to the diet, whereas pelagic fish could not be identified in the samples.
The results are compared with information from other study areas and discussed in relation to the consumption of krill. 相似文献
3.
4.
The dietary composition of juvenile Trematomus newnesi, trawled at Potter Cove, South Shetland Islands, in the summers 2004–2005 and 2005–2006 was analysed using frequency of occurrence
(F%) and dietary coefficient Q (%) methods. The samples consisted exclusively of immature specimens in the range 4–15.4 cm (total length) and are complementary
to those of larger fish from the same site, including adults, which were analysed in previous work. Benthic-demersal organisms
such as gammaridean amphipods and harpacticoid copepods were the main (coefficient Q) and most frequent (F%) prey. The importance of the smaller and larger main prey diminished and increased, respectively, during ontogeny. Pelagic
krill, being negligible in the diet of the small and medium size fish categories, became secondary food, but only for fish
larger than 12 cm. Other taxonomic groups occurred scarcely and constituted occasional food. They were mostly benthic, such
as gastropods, bivalves, isopods, cumaceans, and algae, with the exception of an insignificant number of pelagic ostracods
and calanoid copepods. Unlike the more pelagic/planktivorous mode of life known for late juvenile-adult stages of T. newnesi, including cryopelagy, present results indicate that early juvenile fish remain sheltered among macroalgae beds preying on
the associated community of demersal-benthic organisms. 相似文献
5.
A. R. Wood 《Mycological Progress》2007,6(2):93-99
The holdings of rust fungi on Grewia species (Tiliaceae) housed in the South African National Collection of Fungi (PREM) were examined. They belong to three morphologically
similar, but clearly separable, species of Uredopeltis, and a species of Uredo. Each rust species has a distinct and restricted host range. Ravenelia atrides is a species of Uredopeltis and is transferred accordingly. Several specimens previously accessioned under R. atrides however belong to U. chevalieri. The specimens previously accessioned under Uredo grewiae belong to U. flava, and not U. chevalieri. Three specimens are best placed in Uredo corbiculoides.
Taxonomic novelties
Uredopeltis atrides (Syd. & P. Syd.) A.R. Wood. comb. nov. 相似文献
6.
Summary Two new species of Rhynchospora, R. acanthoma and R. rupestris, are described and illustrated. Their geographical distributions are discussed. The status of R. exilis and its synonymy is clarified. 相似文献
7.
Sarawood Sungkaew Atchara Teerawatananon John A. N. Parnell Chris M. A. Stapleton Trevor R. Hodkinson 《Kew Bulletin》2008,63(4):669-673
Summary A new monotypic bamboo genus Phuphanochloa (Poaceae: Bambusoideae) from north-eastern Thailand is described, together with a new species, P. speciosa. 相似文献
8.
Age and growth of ocellated icefish, Chionodraco rastrospinosus DeWitt and Hureau, 1979, from the South Shetland Islands 总被引:1,自引:0,他引:1
Age and growth of ocellated icefish, Chionodraco rastrospinosus, were investigated using counts of annual growth increments from sagittal otoliths. Samples were collected during research
surveys by benthic trawl carried out around Elephant and South Shetland Islands in January–February 2002 and December 2006–January
2007. A total of 290 specimens were selected for the study, consisting of 120 females and 170 males. The age of fish was estimated
by counting annuli on transverse sections obtained by grinding and polishing whole otoliths embedded in epoxy resin. The precision-of-age
estimates within and between readers were tested applying both the average percent error (APE) and the coefficient of variation
(CV). The estimated age-range was 1–12 for both sexes of C. rastrospinosus. Applying the von Bertalanffy growth function to the age–length data, a growth curve was obtained for each sex. The estimated
values of VB growth parameters L
∞
and k were, respectively, 47.9 cm and 0.28 for females and 42.9 cm and 0.36 for males. Compared to other congeneric species, the
growth performance of C. rastrospinosus was relatively high, being 2.82 and 2.81 in males and females, respectively. Age at sexual maturity was estimated to be about
4 years in both sexes. C. rastrospinosus captured in the studied area consisted mainly of adult specimens between 3 and 8 years, with few older fish. 相似文献
9.
The summer diet of two species of icefishes (Channichthyidae) from the South Shetland Islands and Elephant Island, Champsocephalus gunnari and Chaenocephalus aceratus, was investigated from 2001 to 2003. Champsocephalus gunnari fed almost exclusively on krill (Euphausia superba) in all years. The importance of other taxa (Themisto gaudichaudii, mysids, myctophids) in the diet was negligible. The average feeding rate of Champsocephalus gunnari inferred from an exponential gastric evacuation model was between 1.0 and 1.5% body weight per day. Most of the stomachs of Chaenocephalus aceratus were empty. Stomachs with food contained mainly krill, mysids and fish. Among the fish taken, locally abundant species formed the bulk of the diet: Gobionotothen gibberifrons in 2001, Lepidonotothen larseni and Champsocephalus gunnari in 2002 and L. larseni in 2003. An ontogenetic shift in feeding preference of Chaenocephalus aceratus was observed: fish smaller than 30 cm fed on krill and mysids, while larger animals relied primarily on fish. 相似文献
10.
Yi-Zhi Zhao 《Kew Bulletin》2008,63(2):345-346
Summary
Caragana aliensis a new species from Tibet, China, is described and illustrated. 相似文献
11.
D. J. Goyder 《Kew Bulletin》2008,63(2):331-333
Summary
Funastrum rupicola Goyder, a new species of Apocynaceae: Asclepiadoideae from Bolivia, is described and illustrated. The conservation status of this species is assessed. 相似文献
12.
Genetic resemblance of chars Salvelinus alpinus krasheninnikovi (Salvelinus malma krasheninnikovi) of 35 samples collected in five Kuril Islands--Shumshu, Paramushir, Onekotan, Iturup, and Kunashir--has been studied by the PCR-RAPD method. In the limits of each island, both resident isolates and anadromous forms give strictly supported clusters distinct from samples from the other islands. The samples from five islands form three superclusters: the first from Kunashir and Iturup Islands, the second from Paramushir and Onekotan Islands, and the third from Shumshu Island. The possible reasons for genetic similarity of resident and anadromous forms of Dolly Varden chars inhabiting reservoirs of a definite island are considered (the founder effect, homing, limited migration). 相似文献
13.
Cabillus atripelvicus is described from three specimens, 26.1–40.6 mm in standard length, collected from depth 17–29 m in the Ogasawara Islands.
In addition, two small specimens taken by dredge in 50–55 m from Sagami Bay, Honshu, and one from Tachibana Bay, Kyushu, are
identified as this species but not designated as paratypes. Cabillus atripelvicus is distinguished from the four other described species of the genus by its high count of 18–20 pectoral rays, presence of
median predorsal scales, longer pectoral fins, and distinctive color pattern, including black pelvic fins. The range of C. lacertops Smith, 1959 is extended east to the Marshall Islands and that of C. tongarevae (Fowler, 1927) east to American Samoa. More species remain to be described in the genus.
Supplementary material to this paper is available in electronic format at 相似文献
14.
A new Dactylella species, Dactylella alba was isolated from the ascospores of Orbilia alba collected in Wenshan County, Yunnan Province, China. Conidiophores were either not branched or occasionally branched, bearing
divergent sterigmata on the tip with single conidium on each. Conidia were elongated ellipsoids, 1–2 septate, mostly 1 septate.
By combining the ITS sequence with morphological characteristics, a new anamorphic species is described and illustrated together
with its teleomorph. 相似文献
15.
João Marcelo Alvarenga Braga 《Kew Bulletin》2008,63(2):309-314
Summary
Calathea dryadica and Calathea reginae are described, circumscribed and illustrated. These new species are probably endemic to the Atlantic Forest of Rio de Janeiro
State in Southeast Brazil and are considered critically endangered because of the restricted geographic area of occurrence,
sometimes enclosed by densely urbanised areas. 相似文献
16.
17.
Summary
Erythroxylum longisetulosum I. Loiola & M. F. Sales and E. timothei I. Loiola & M. F. Sales (sect. Rhabdophyllum) from north-eastern Brazil are described and illustrated, and their taxonomic and ecological relationships are discussed. 相似文献
18.
Aime Didier B. Begoude Marieka Gryzenhout Michael J. Wingfield Jolanda Roux 《Antonie van Leeuwenhoek》2010,98(3):263-278
Native Terminalia spp. in West Africa provide a popular source of construction timber as well as medical, spiritual and social benefits to
rural populations. Very little is, however, known regarding the diseases that affect these trees. During an investigation
into possible diseases of Terminalia spp. in Cameroon, orange to yellow fungal fruiting structures, resembling those of fungi in the Cryphonectriaceae, were commonly
observed on the bark of native Terminalia ivorensis, and on dead branches of non-native Terminalia mantaly. In this study the fungus was identified based on morphological features as well as DNA sequence data (ITS and β-tubulin)
and its pathogenicity was tested on T. mantaly seedlings. Our results showed that isolates of this fungus represent a previously undescribed genus in the Cryphonectriaceae,
which we describe as Aurifilum
marmelostoma gen. et sp. nov. Pathogenicity tests revealed that A. marmelostoma is pathogenic on T. mantaly. These tests, and the association of A. marmelostoma with disease symptoms on T. ivorensis, suggest that the fungus is a pathogen of this important tree. 相似文献
19.
Nguyen Van Du 《Kew Bulletin》2008,63(3):491-493
Summary
Typhonium stigmatilobatum V. D. Nguyen, a new species from Vietnam, is described and illustrated. 相似文献
20.
J. Jennifer Luangsa-ard Suchada Mongkolsamrit Donnaya Thanakitpipattana Artit Khonsanit Kanoksri Tasanathai Wasana Noisripoom Richard A. Humber 《Mycological Progress》2017,16(4):369-391
In several surveys in the tropical forests in Thailand, specimens that looked morphologically similar to Metarhizium martiale and Cordyceps variegata, as well as other Metarhizium species were collected and cultured in vitro. A combined phylogeny of several genes including the small (18S) and large (28S) subunits of the ribosomal DNA, elongation factor 1-α (TEF), RNA polymerase II subunits 1 and 2 (RPB1, RPB2) genes has shown these to be new taxa in the Clavicipitaceae. Nigelia is described as a new genus closely related to Metarhizium, to the scale insect pathogens Aschersonia (Hypocrella), Samuelsia and Moelleriella, and to plant pathogens in Claviceps and Balansia, and other relatives. Nigelia comprises M. martiale and a new species Nigelia aurantiaca, which has been found infecting lepidopteran larvae and which produces pseudoimmersed, obliquely arranged, obpyriform perithecia with curved or bent ostioles and with whole (non-separating) cylindric ascospores. Metarhizium chaiyaphumense, M. kalasinense, M. prachinense, M. samlanense, and M. takense are described as new species of Metarhizium. Metarhizium martiale is transferred to Nigelia, and Paecilomyces reniformis is transferred to Metarhizium. 相似文献