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1.
Summary.  The golden‐flowered Masdevallia niesseniae Luer from Colombia is described and illustrated from the type collection.  相似文献   
2.
Summary The occurrence of Crassulacean acid metabolism (CAM), as judged from 13C values, was investigated in epiphytes and some related plant species at a series of sites covering the approximate altitudinal range of epiphytes in Papua New Guinea. Comprehensive collections were made at each site and the occurrence of water storage tissue and blade thickness was also determined. Some 26% of epiphytic orchids from a lowland rainforest (2–300 m.a.s.l) showed 13C values typical of obligate CAM and possessed leaves thicker than 1 mm. A second group of orchids, mostly with succulent leaves, possessed intermediate 13C values between -23 and -26% and accounted for 25% of the total species number. Some species of this group may exhibit weak CAM or be facultative CAM plants. The remainder of the lowland rainforest species appeared to be C3 plants with 13C values between -28 and -35%. and generally possessed thin leaves. Obligate CAM species of orchids from a lower montane rainforest (1175 m.a.s.l) comprised 26% of the species total and mostly possessed thick leaves. The remainder of the species were generally thin-leaved with 13C values between -26 and -35%. largely indicative of C3 photosynthesis. Orchids with intermediate 13C values were not found in the lower montane rainforest. Obligate CAM appeared to be lacking in highland epiphytes from an upper montane rainforest and subalpine rainforest (2600–3600 m.a.s.l). However the fern, Microsorium cromwellii had a 13C value of -21.28%. suggesting some measure of CAM activity. Other highland ferns and orchids showed more negative °13C values, up to-33%., typical of C3 photosynthesis. The highland epiphytic orchids possessed a greater mean leaf thickness than their lowland C3 counterparts due to the frequent occurrence of water storage tissue located on the adaxial side of the leaf. It is suggested that low daytime temperatures in the highland microhabitats is a major factor in explaining the absence of CAM. The increased frequency of water storage tissue in highland epiphytes may be an adaptation to periodic water stress events in the dry season and/or an adaptation to increased levels of UV light in the tropicalpine environment.  相似文献   
3.
The Tandanicolinae is reviewed, redefined and considered a subfamily of the Fellodistomidae. The Monodhelminthinae Dollfus, 1937, Mehratrematinae Srivastava, 1939, Prosogonariinae Mehra, 1963 and Buckleytrematinae Yamaguti, 1971 are synonyms of the Tandanicolinae. Genera included in the Tandanicolinae are Tandanicola, Monodhelmis, Buckleytrema and Prosogonarium. Burnellus and Mehratrema are made new synonyms of Monodhelmis. The composition of each genus is reviewed. Monodhelmis arii Yamaguti, 1952, Mehratrema arii Gu & Shen, 1979, Mehratrema dollfusi Srivastava, 1939, Monodhelmis philippinensis Velasquez, 1961, Mehratrema polynemusinis Chauhan, 1943 and Mehratrema skrjabini Karyakarte, 1969 are considered synonyms of Monodhelmis torpedinis. Monodhelmis elongatus Bilqees, 1970 is considered a species inquirenda. Prosogonarium angelae n. sp. is described from Euristhmus lepturus from Moreton Bay, Queensland. It is distinguished by the number and distribution of the vitelline follicles and the extent of the caeca. New records are given for Monodhelmis torpedinis from Arius graeffei and E. lepturus, M. trichofurcata from Tandanus tandanus, and Buckleytrema indica from A. graeffei, all from southern Queensland. Buckleytrema indica is redescribed and B. postacetabulorchis is synonymised with that species. Relationships within the Tandanicolinae were considered by cladistic analysis.  相似文献   
4.
Two species of the Zoogonidae are recorded from Heron Island on the southern Great Barrier Reef. Steganoderma (Lecithostaphylus) gibsoni n. sp. is described from the intestine of Abudefduf whitleyi (Pomacentridae). The new species is distinguished by the combination of the following: pedunculate ventral sucker, caeca extending well past testes, presence of two-chambered internal seminal vesicle, vitelline follicles extending only to anterior margin of testes, and testes close to ventral sucker. Zoogonus pagrosomi Yamaguti, 1939 is recorded from Lethrinus atkinsoni (Lethrinidae). This species has been recorded previously only from a sparid from Japan. A new combination, Steganoderma (Lecithostaphylus) fugus (Zhang, Qiu & Li, 1986), is made.  相似文献   
5.
Coelogyne kaliana from Malaysia is illustrated and the history of its collection and habitat are described. Distinctions from related species are discussed, and suggestions for its cultivation are given.  相似文献   
6.
7.
Cutmore  S. C.  Yong  R. Q.-Y.  Reimer  J. D.  Shirakashi  S.  Nolan  M. J.  Cribb  T. H. 《Systematic parasitology》2021,98(5-6):641-664

Ankistromeces Nolan & Cribb, 2004 and Phthinomita Nolan & Cribb, 2006 are sister genera of threadlike blood flukes (Trematoda: Aporocotylidae) infecting teleost fishes of the tropical Indo-west Pacific. Here, we report new collections of these genera from Australia, Indonesia, and Japan. A new species of Ankistromeces, Ankistromeces kawamurai n. sp., is described from Siganus spinus (Linnaeus) off Okinawa, Japan, and a new species of Phthinomita, Phthinomita abdita n. sp., from Choerodon cephalotes (Castelnau), in Moreton Bay, Australia; the new species are morphologically cryptic within their respective genera and are delineated by molecular and ecological data. Ankistromeces olsoni Nolan & Cribb, 2006 is reported from Siganus fuscescens (Houttuyn) off Heron Island (southern Great Barrier Reef), Lizard Island (northern Great Barrier Reef), and Okinawa and Wakayama Prefectures, Japan and from Siganus spinus (Linnaeus) from off Bali, Indonesia. Ankistromeces mariae Nolan & Cribb, 2004 is re-reported from the type-host, Meuschenia freycineti (Quoy & Gaimard), from a new location, Gypsy Bay, Tasmania. Phthinomita poulini Nolan & Cribb, 2006 is re-reported from its type-locality, Lizard Island, from a range of mullids, including five new host species, and its range is extended to include Moreton Bay. Phthinomita symplocos Nolan & Cribb, 2006 is reported from Bali and P. hallae Nolan & Cribb, 2006, P. jonesi Nolan & Cribb, 2006, P. littlewoodi Nolan & Cribb, 2006, and P. munozae Nolan & Cribb, 2006 are each re-reported from their type-host and type-localities. New cox1 mtDNA data were generated for all known species of these two genera from new and archival material. Analyses of these data enabled an evaluation of all known Phthinomita species; P. robertsthomsoni Nolan & Cribb, 2006 is synonymised with P. adlardi Nolan & Cribb, 2006, and P. brooksi Nolan & Cribb, 2006 is synonymised with P. sasali Nolan & Cribb, 2006. We highlight the failure of ITS2 data to delineate closely related aporocotylid species. In contrast, cox1 sequence data are proving reliable and effective in this context and we recommend their incorporation in future studies of blood fluke taxonomy.

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8.
Introduction     
Abstrat

In this paper we discuss genetic discourses and practices in stem cell science. We report on how biomedical scientists, in both the UK and the USA, view the scientific literature and their own experimental research in the emerging field of human embryonic stem (hES) cells. We focus on the genetic manipulation of stem cells to make specialized (beta) cells as a potential cure for diabetes. We draw on Gieryn's notion of boundary work as an analytical motif, and suggest this is a productive way to theorize boundary crossings in the shifting landscapes of expectations in the field of new medical technologies. We argue that initial expectations of a revolution in regenerative medicine have been damped down by the difficulties of making insulin producing pancreatic beta cells from stem cells. We contend the consequent shifts in expectations have led to the emergence of other more radical experimental strategies (such as using oncogenes) in the search for potential cures for Type 1 diabetes. In conclusion, we argue that regenerative medicine is a fruitful example of the shaping of contested biomedical landscapes and we contend that embryonic stem cells are a productive case study of the interactions between genetics, science and society.  相似文献   
9.

We provide molecular data (cox1, 18S rDNA and 28S rDNA) for 17 acanthocephalan species and 20 host-parasite combinations from Australian marine teleosts collected from off Queensland, Australia. Fourteen of these acanthocephalans are characterised with molecular data for the first time and we provide the first molecular data for a species of each of the genera Heterosentis Van Cleave, 1931, Pyriproboscis Amin, Abdullah & Mhaisen, 2003 and Sclerocollum Schmidt & Paperna, 1978. Using 18S and 28S rDNA sequences, the phylogenetic position of each newly sequenced species is assessed with both single-gene and concatenated 18S+28S maximum likelihood and Bayesian inference analyses. Additional phylogenetic analyses focusing on the genus Rhadinorhynchus Lühe, 1912 and related lineages are included. Our phylogenetic results are broadly consistent with previous analyses, recovering previously identified inconsistencies but also providing new insights and necessitating taxonomic action. We do not find sufficient evidence to recognise the Gymnorhadinorhynchidae Braicovich, Lanfranchi, Farber, Marvaldi, Luque & Timi, 2014 as distinct from the Rhadinorhynchidae Lühe, 1912. The family Gymnorhadinorhynchidae and its sole genus, Gymnorhadinorhynchus Braicovich, Lanfranchi, Farber, Marvaldi, Luque & Timi, 2014, are here recognised as junior synonyms of Rhadinorhynchidae and Rhadinorhynchus, respectively. The two species currently assigned to Gymnorhadinorhynchus are recombined as Rhadinorhynchus decapteri (Braicovich, Lanfranchi, Farber, Marvaldi, Luque & Timi, 2014) n. comb. and Rhadinorhynchus mariserpentis (Steinauer, Garcia-Vedrenne, Weinstein & Kuris, 2019) n. comb. In all of our analyses, Rhadinorhynchus biformis Smales, 2014 is found basal to the Rhadinorhynchidae + Transvenidae Pichelin & Cribb, 2001, thus resulting in a paraphyletic Rhadinorhynchidae. It appears that R. biformis may require a new genus and family; however, morphological data for this species are currently insufficient to adequately distinguish it from related lineages, thus we defer the proposal of any new higher-rank names for this species. Species of the genus Sclerocollum, currently assigned to the Cavisomidae Meyer, 1932, are found nested within the family Transvenidae. We transfer the genus Sclerocollum to the Transvenidae and amend the diagnosis of the family accordingly. The genera Gorgorhynchoides Cable & Linderoth, 1963 and Serrasentis Van Cleave, 1923, currently assigned to the Rhadinorhynchidae, are supported as sister taxa and form a clade in the Polymorphida. We transfer these genera and Golvanorhynchus Noronha, Fabio & Pinto, 1978 to an emended concept of the Isthomosacanthidae Smales, 2012 and transfer this family to the Polymorphida. Lastly, Pyriproboscis heronensis (Pichelin, 1997) Amin, Abdullah & Mhaisen, 2003, currently assigned to the Pomphorhynchidae Yamaguti, 1939, falls under the Polymorphida in our analyses with some support for a sister relationship with the Centrorhynchidae Van Cleave, 1916. As this species clearly does not belong in the Pomphorhynchidae and is morphologically and molecularly distinct from the lineages of the Polymorphida, we propose the Pyriprobosicidae n. fam. to accommodate it.

  相似文献   
10.
Kudoa spp. from the musculature and intestinal mucosa of species of the teleost family Apogonidae were examined for their taxonomic identity. Two novel species are characterised: Kudoa cheilodipteri n. sp. from the musculature of Cheilodipterus quinquelineatus Cuvier, Ostorhinchus cyanosoma (Bleeker) and O. aureus (Lacépède); and Kudoa cookii n. sp. from the submucosa of the intestines of O. cookii (Macleay) only. Both species are characterised using morphology, small subunit ribosomal DNA (SSU rDNA), large subunit ribosomal DNA (LSU rDNA), and biological characters. Three new host records, O. cyanosoma, O. aureus and Apogon doederleini, and associated geographical, morphological and genetic data are also provided for Kudoa whippsi Burger & Adlard, 2010. Morphological and molecular intra-specific variation of all isolates assigned to K. whippsi is also examined. Phylogenetic analyses further support the idea that tissue tropism is a distinguishing character between morphologically similar species; species reported here display close relatedness to morphologically similar species infecting the same tissue within their hosts.  相似文献   
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