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1.
The subsection Asperae of genus Hydrangea L. (Hydrangeaceae) has been investigated for three reasons: several ambiguous classifications concerning Hydrangea aspera have been published, unexpected differences in genome size among seven accessions have been reported Cerbah et al. (Theor Appl Genet 103:45–51, 2001), and two atypical chromosome numbers (2n = 30 for Hydrangea involucrata and 2n = 34 for H. aspera) have been found when all other species of the genus present 2n = 36. Therefore, these two species and four subspecies of Hydrangea in all 29 accessions were analyzed for their genome size, chromosome number, and karyotype features. This investigation includes flow cytometric measurements of nuclear DNA content and bases composition (GC%), fluorochrome banding for detection of GC- and AT-rich DNA regions, and fluorescent in situ hybridisation (FISH) for chromosome mapping of 5 S and 18 S-5.8 S-26 S rDNA genes. In the H. aspera complex, the genome size ranged from 2.98 (subsp. sargentiana) to 4.67 pg/2C (subsp. aspera), an exceptional intraspecific variation of 1.57-fold. The mean base composition was 40.5% GC. Our report establishes the first karyotype for the species H. involucrata, and for the subspecies of H. aspera which indeed present different formulae, offering an element of discrimination. FISH and fluorochrome banding revealed the important differentiation between these two species (H. involucrata and H. aspera) and among four subspecies of the H. aspera complex. Our results are in agreement with the Chinese classification that places the groups Kawakami and Villosa as two different species: Hydrangea villosa Rehder and Hydrangea kawakami Hayata. This knowledge can contribute to effective germplasm management and horticultural use.  相似文献   

2.
The bathyal genus Penopus (Ophidiidae) is revised based on 23 specimens. One specimen from the Ryukyu Trench represents a new species, Penopus japonicus. The remaining 22 specimens were found on both sides of the Atlantic Ocean, and neither 28 meristic and morphometric characters nor several morphological characters show any differences between the two populations. This supports Séret (1988), who considered Penopus macdonaldi Goode and Bean 1896 a junior synonym of Penopus microphthalmus (Vaillant 1888). The new Japanese species can be separated from the Atlantic species by having fewer rays in the dorsal (117 vs. 135–158) and anal (89 vs. 106–122) fins, the squamation of the head restricted to the middle part of the preopercle versus the squamation covering the dorsum, preopercle and the opercle in part, a distinct spine behind the posterior nostril versus the spine hardly visible and 9 spines on the hind margin of the preopercle versus 4–7 spines.  相似文献   

3.
Neoskrjabinolepis (Neoskrjabinolepidoides) nuda n. sp. is described from the shrews Sorex unguiculatus (type-host), S. gracillimus, S. isodon and S. caecutiens on Sakhalin Island, Russia. The new species is characterised by: rostellar hooks 40–44 μm long and provided with small epiphyseal thickening of the handle; a long (95–100 μm) cirrus consisting of basal region with claw-shaped spines, a parabasal region with thin needle-shaped spines and an unarmed distal region; a cirrus-sac extending well into the median field; and 15–22 eggs per gravid uterus. A review of the species of Neoskrjabinolepis Spasskii, 1947 is presented. Currently, this genus includes nine species and is divided in two subgenera on the basis of strobilar development, which is gradual in the subgenus Neoskrjabinolepis (four species) and serial in the subgenus Neoskrjabinolepidoides Kornienko, Gulyaev & Mel’nikova, 2006 (five species). An amended generic diagnosis and an identification key to Neoskrjabinolepis spp. are presented.  相似文献   

4.
The myrophine ophichthid fishes (worm eels) Muraenichthys aoki Jordan and Snyder 1901 and Muraenichthys gymnotus Bleeker 1857 are redescribed as valid species of Scolecenchelys based on the types and non-type specimens collected from the Indo-Pacific. Because both species are similar to each other in having acute snouts, the posterior margin of the eye before the rictus, and their dorsal-fin origins located slightly posterior to a vertical line through the anus, Scolecenchelys aoki has usually been regarded as a junior synonym of Scolecenchelys gymnota. However, S. aoki is clearly distinguishable from S. gymnota by having a median groove on the ventral side of snout (absent in S. gymnota), uniserial maxillary teeth in smaller specimens (<200 mm TL; vs. biserial), three infraorbital sensory pores at postorbital area (vs. two), and more numerous vertebrae (56–65 in predorsal vs. 51–57; 53–58 in preanal vs. 47–52). Scolecenchelys aoki is restricted to Japanese waters and regarded as a senior synonym of Muraenichthys borealis Machida and Shiogaki 1990. Scolecenchelys gymnota is widely distributed in the Indo-Pacific, from South Africa and the Red Sea to Samoa, north to Okinawa, Japan. Sphagebranchus huysmani Weber 1913 and Muraenichthys fowleri Schultz 1943 are synonymized under S. gymnota.  相似文献   

5.
A new species of Litomosoides Chandler, 1931 was collected from the abdominal cavity of Oxymycterus nasutus Waterhouse (Rodentia: Cricetidae) in the grassland of the Departamento Rocha, Uruguay. Litomosoides nasuti n. sp. belongs to the ‘sigmodontis group’, and is characterised by: salient amphids; two ventral and one dorsal labial papillae, but no cephalic papillae; a buccal capsule with a transparent anterior segment and an annular asymmetrical thickening; a muscular oesophagus; a bottle-shaped buccal cavity; the male with symmetrically situated cloacal papillae (one pair ad-cloacal and three pairs post-cloacal); phasmids displaced laterally to the longitudinal axis; and microfilariae without terminal nuclei in the tail tip. It resembles five known species; three of which have been recovered from Oxymycterus spp. in neighbouring countries. However, the new species can be differentiated from L. sigmodontis Chandler, 1931 by the shape and size of the buccal capsule; from L. navonae Notarnicola, 2005 by the muscular oesophagus; from L. legerae Bain, Petit & Berteaux, 1980 by the length of the oesophagus and the cephalic papillae; from L. anguyai Notarnicola, Bain & Navone, 2002 by the absence of lappets in the female tail; and from L. oxymycteri Notarnicola, Bain & Navone, 2000 by absence of pre-cloacal papillae. L. legerae from O. quaestor and L. sigmodontis from Sigmodon hispidus in North America are closely related species, as indicated by Brant & Gardner’s phylogenetic tree based on morphological characters. However, a new analysis is needed to include the recently described Argentinean species for a better understanding of the diversification of this genus.  相似文献   

6.
7.
The type specimens of platycephalid Platycephalus endrachtensis Quoy and Gaimard 1825 are regarded as being conspecific with Platycephalus arenarius Ramsay and Ogilby 1886, so the latter becomes a junior synonym. This species is characterized as having a caudal fin with four or more longitudinal dark bands and lacking a yellow blotch. It is also found that Platycephalus westraliae (Whitley 1938), which had been considered to be a junior synonym of Platycephalus bassensis Cuvier 1829, is a valid species. Specimens that recently had been mistakenly identified as “P. endrachtensis,” having the caudal fin with three or four longitudinal dark bands and a yellow blotch on the upper lobe, should be referred to P. westraliae.  相似文献   

8.
Recent phylogenetic research suggests that Malvaceae s.l. comprises formerly Tiliaceae, Byttneriaceae, Bombacaceae, and Sterculiaceae. Corchoropsis is traditionally included in Tiliaceae or Sterculiaceae and is distributed in China, Korea, and Japan. One to three species have been recognized for this genus. Phylogenetic relationships among the Malvacean taxa have been intensively studied with molecular data, and the evolution of their morphological characteristics has been re-interpreted accordingly. However, no Corchoropsis species have been included for their phylogenetic position. Here, three chloroplast coding regions—rbcL, atpB, and ndhF, from Corchoropsis psilocarpa and Corchoropsis crenata—were amplified and sequenced, then compared with other Malvacean taxa. This analysis of the three plastid gene sequences now places Corchoropsis species in Dombeyoideae, as previously proposed by Takeda (Bull Misc Inform Kew 365, 1912), Tang (Cathaya 4:131–150, 1992), and Bayer and Kubitzki (2003). Within Dombeyoideae, Corchoropsis forms a strongly supported sister relationship with the DombeyaRuizia clade.  相似文献   

9.
The genus Prosopis (Leguminosae, Mimosoideae), comprises 44 species widely distributed in arid and semi-arid zones. Prosopis pallida (Humb. & Bonpl. ex Willd.) Kunth and P. juliflora (Sw.) DC. are the two species that are truly tropical apart from P. africana, which is native to tropical Africa (Pasiecznik et al. 2004), and they have been introduced widely beyond their native ranges. However, taxonomic confusion within the genus has hampered exploitation and better management of the species. The present study focusses primarily on evaluating the genetic relationship between Prosopis species from the section Algarobia, containing most species of economic importance, though P. tamarugo from section Strombocarpa is also included for comparison. In total, 12 Prosopis species and a putative P. pallida × P. chilensis hybrid were assessed for their genetic relationships based on RAPD markers and microsatellite transferability. The results show that P. pallida and P. juliflora are not closely related despite some morphological similarity. Evidence also agrees with previous studies which suggest that the grouping of series in section Algarobia is artificial.  相似文献   

10.
The Scorpaena cardinalis complex, including S. cardinalis, S. jacksoniensis and S. orgila, is defined. The genus Ruboralga (type species: S. jacksoniensis) is regarded as a junior synonym of Scorpaena. Scorpaena jacksoniensis Steindachner 1866, previously treated as a junior synonym of Scorpaena cardinalis Solander and Richardson 1842, is regarded here as a valid species. Scorpaena cookii Günther 1874, previously treated as a valid species, is regarded here as a junior synonym of S. cardinalis. Thus, recent recognition of the two Australasian scorpionfishes, i.e., S. cardinalis and S. cookii, are re-identified in this study as S. jacksoniensis and S. cardinalis, respectively. Scorpaena plebeia Solander 1842 is regarded as a junior synonym of S. cardinalis. Scorpaena jacksoniensis is distributed along the east coast of Australia from southern Queensland to eastern Victoria, whereas S. cardinalis occurs around northern New Zealand, the Kermadec Islands and offshore islands of the Tasman Sea. A neotype is designated for S. cardinalis. Morphological changes with growth in the two species are described in detail.  相似文献   

11.
The Bacteroides genus, the most prevalent anaerobic bacteria of the intestinal tract, carries a plethora of the mobile elements, such as plasmids and conjugative and mobilizable transposons, which are probably responsible for the spreading of resistance genes. Production of β-lactamases is the most important resistance mechanism including cephalosporin resistance to β-lactam agents in species of the Bacteroides fragilis group. In our previous study, the cfxA gene was detected in B. distasonis species, which encodes a clinically significant broad-spectrum β-lactamase responsible for widespread resistance to cefoxitin and other β-lactams. Such gene has been associated with the mobilizable transposon Tn4555. Therefore, the aim of this study was to detect the association between the cfxA gene and the presence of transposon Tn4555 in 53 Bacteroides strains isolated in Rio de Janeiro, Brazil, by PCR assay. The cfxA gene was detected in 11 strains and the Tn4555 in 15. The transposon sequence revealed similarities of approximately 96% with the B. vulgatus sequence which has been deposited in GenBank. Hybridization assay was performed in attempt to detect the cfxA gene in the transposon. It was possible to associate the cfxA gene in 11 of 15 strains that harbored Tn4555. Among such strains, 9 presented the cfxA gene as well as Tn4555, but in 2 strains the cfxA gene was not detected by PCR assay. Our results confirm the involvement of Tn4555 in spreading the cfxA gene in Bacteroides species.  相似文献   

12.
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   

13.
The chemical composition of secretions from opisthonotal (oil) glands in four species of the oribatid mite genus Oribotritia (Mixonomata, Euphthiracaroidea, Oribotritiidae) was compared by means of gas chromatography—mass spectrometry. The secretions of all, O. banksi (from North America) and three Austrian oribotritiids (O. berlesei, O. hermanni, O. storkani), are shown to be based on certain unusual compounds, the iridoid monoterpenes chrysomelidial and epi-chrysomelidial and the diterpene β-springene. These components probably represent general chemical characteristics of oribotriid oil glands. Their relative abundance in the secretions along with further components (mainly saturated and unsaturated C13-, C15-, C17-hydrocarbons, and the tentatively identified octadecadienal) led to well-distinguishable, species-specific oil gland secretions profiles. In addition a reduced set of “Astigmata compounds” (sensu Sakata and Norton in Int J Acarol 27:281–291, 2001)—namely the two monoterpenes neral and geranial—could be detected in extracts of O. banksi nevertheless indicating the classification of euphthiracaroids within the (monophyletic) group of “Astigmata compounds-bearing”-Oribatida. These compounds are considered to be apomorphically reduced in all Austrian species. Our findings emphasize the potential of chemosystematics using oil gland secretion profiles in the discrimination of morphologically very similar, syntopically living or even cryptic oribatid species.  相似文献   

14.
Aphthalmichthys kuro, described by Kuroda (1947) based on a specimen from Suruga Bay, Japan, is referred to Callechelys (family Ophichthidae, subfamily Ophichthinae). It differs from its congeners in its vertebral number (142–146), tail length (2.0–2.1 in TL), and coloration (brownish black). The holotype is lost; we herein designate a neotype and redescribe and illustrate the species based on 5 specimens from Japan and 2 from Taiwan.  相似文献   

15.
Summary  Eleven species comprising the Madagascan genus Vaughania are subsumed within the large pantropical genus Indigofera. Six new combinations are made; the remaining species were originally described in Indigofera.  相似文献   

16.
On the family Brassicaceae, the causal agent responsible for downy mildew disease was originally regarded as a single species, Peronospora parasitica (now under Hyaloperonospora), but it was recently reconsidered to consist of many distinct species. In this study, 11 specimens of Peronospora drabae and P. norvegica parasitic on the genus Draba were investigated morphologically and molecularly. Pronounced differences in conidial sizes (P. drabae: 14–20 × 12.5–15.5 μm; P. norvegica: 20–29 × 15.5–22 μm) and 7.8% sequence distance between their ITS1-5.8S-ITS2 rDNA sequences confirmed their status as distinct species. Based on ITS phylogeny and morphology (monopodially branching conidiophores, flexuous to sigmoid ultimate branchlets, hyaline conidia and lobate haustoria), the two species unequivocally belong to the genus Hyaloperonospora and not to Peronospora to which they were previously assigned. Therefore, two new combinations, Hyaloperonospora drabae and H. norvegica, are proposed. The two taxa are illustrated and compared using the type specimen for H. norvegica and authentic specimens for H. drabae, which is lectotypified.  相似文献   

17.
Zonneveld (Pl Syst Evol 281:217–245, 2009) proposed an infrageneric classification of Tulipa (Liliaceae) based on the nuclear content determined by flow cytometry and available morphological data. The nomenclatural consequences of this are discussed here, involving the typification of generic and infrageneric names. Additional notes on some species are given. Four subgenera are distinguished, of which two are new; ten sections are proposed, four new; three new combinations are made, and seven lectotypes are designated. Tulipa praecox Ten. is a later homonym of T. praecox Cav. (Descripcíon de las plantas. 2: 448, 625, 1803); its correct name is Tulipa agenensis DC. Tulipa lemmersii Zonn., A. Peterse, J. de Groot is validated here by giving the type citation.  相似文献   

18.
19.
Summary  A taxonomic revision of the palm genus Podococcus (Arecaceae) is presented. Two species are recognised: P. barteri, a species relatively widespread in a coastal band from Nigeria to the D. R. Congo and P. acaulis, a species previously considered conspecific to P. barteri, almost exclusively confined to Gabon. The taxonomic history, morphology, distribution and conservation status of the genus and each species are discussed  相似文献   

20.
The type species of Trimmatothele is shown to differ from Verrucaria only by the multispored asci. Trimmatothele is consequently regarded as a younger synonym of Verrucaria, and the new combination Verrucaria perquisita proposed. The species is just known from Europe, where it is very rare on calcareous rocks and has a boreo-alpine distribution. Trimmatothelopsis antarctica is a very distinct lichen, not related with Verrucaria, and the new genus Oevstedalia is described to accommodate it. Oevstedalia is characterized by relatively pale perithecia with a hyphal wall, abundant pseudoparaphyses, sparse, thin, basally branched and anastomosed interascal filaments, an I− and K/I− centre, and very large, subcylindrical, entirely thin-walled, K/I+ blue asci containing in the living state 8 conidial balls filled with numerous ascoconidia. Oevstedalia might be related to the Epigloeaceae (family inc. sedis) and represents the first example of a lichenized ascomycete forming true ascoconidia. O. antarctica appears to be endemic in Antarctica, where it seems to be widespread and relatively common. No material is available for Trimmatothele umbellulariae and Lesdainea maritima, and no final conclusion can be given for the taxonomic status of these two species.  相似文献   

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