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1.
A new species of the coral snake genus Sinomicrurus is described based on four specimens from southern Hainan Island(three specimens from Tianchi,Jianfengling National Nature Reserve,one specimen from Diaoluoshan National Nature Reserve),Hainan Province,China.Morphologically,the new species is rather similar to Sinomicrurus kelloggi.However,it is distinct from S.kelloggi by the pattern on the head,the head length,head length/width,the number of infralabial scales,number of bands on dorsal body,and number of blotches on the belly.  相似文献   

2.
Six Ctenoplectra species are recorded from Southeast Asia and Taiwan. They are C. chalybea Smith, C. cornuta Gribodo, C. davidi Vachal, C. elsei Engel, C. sandakana sp. nov. and C. vagans Cockerell. Females of C. sandakana sp. nov. from North Borneo are similar to the mainland species C. chalybea , but differ mainly in the clypeal keel and the length of the antennal segments. The small blackish species, C. cornuta , is distributed in Myanmar, China and Taiwan and C. davidi is distributed in China, Russia and Taiwan; both species are seen at the flowers of Thladiantha . Ctenoplectra chalybea was collected from the Malay Peninsula, Myanmar, Taiwan and Vietnam. Ctenoplectra apicalis Smith and C. kelloggi Cockerell are allied to C. chalybea ; however, C. kelloggi is excluded from this study due to insufficient material. A key to the six known Ctenoplectra species is given. The large metallic species, C. chalybea and C. elsei , visit flowers of Momordica cochinchinensis (Lour.) Spreng. For the first time observations on the nest structures of C. chalybea and C. cornuta are presented. They choose remarkable places, such as artificial structures and buildings, for nest sites. The nest architecture prevents rain and direct sunlight from entering the nest. Bees used pre-existing holes or crevices in wood for nesting shelters and collected soil and appeared to mix it with some other substance to build nests. The cell lining materials and rubbing behaviors against the cell wall suggest that Ctenoplectra bees use floral oil mainly for cell lining materials.  相似文献   

3.
4.
湖南省爬行动物新纪录2种   总被引:4,自引:1,他引:3  
本文记叙了湖南省新发现的2种爬行动物,它们分别是壁虎科的半叶趾虎(Hemiphyllodactylusyunnanensis);眼镜蛇科的福建丽纹蛇(Calliophiskelloggi)。半叶趾虎的标本存放于湖南师范大学生物系,福建丽纹蛇的标本存放于中南林学院环资系。  相似文献   

5.
云南老君山发现福建华珊瑚蛇   总被引:1,自引:0,他引:1  
<正>2014年4月20日,在云南省麻栗坡县老君山的季风常绿阔叶林(22°57′0.97″N,104°36′17.27″E,海拔1 218 m)采集到蛇类标本1号,经鉴定为福建华珊瑚蛇(Sinomicrurus kelloggi,图1)。该物种国内已知分布于安徽、浙江、福建、江西、湖南、海南、广东、广西、贵州和重庆,国外分布于越南和老挝。本次发现为云南省首次发现。标本现保存在国家林业局昆明勘察设计院标本室。  相似文献   

6.
The ovarian structure, sexual maturation, annual reproductive cycle, and spawning periodicity of the shore scorpionfish, Scorpaenodes littoralis, in Uchiura Bay, central Japan, were examined using specimens collected between May 1995 and March 1998 and fishes reared in laboratory. The ovarian stroma and blood vessels run longitudinally through the center of each ovarian lobe. The ovarian peduncles radiate from the central stroma. During the spawning season, gelatinous material is secreted from the epithelia of both the ovarian peduncle and ovarian wall, and the epithelia show morphological changes accompanying the ovarian maturation cycle. The minimum standard length at maturity was 55.2mm for males and 40.2mm for females. Males with mature testes were collected from March to November. Females in the mature or post spawning stages were collected between May and October, when the mean gonadosomatic indices were also high. This indicates that the spawning season of this species occurs between May and October. Four successive types of oocytes were grouped in the mature ovary, comprised of mature, late and early vitellogenic and previtellogenic oocytes respectively, suggesting that this species is a multiple spawner. Four captive females spawned repeatedly at intervals of 2–8 days over a prolonged period (4–8 months); a 2-day spawning interval was the most common for all females. This suggests that female S. littoralis have a 48-h spawning cycle in captivity.  相似文献   

7.
A cladistic analysis of Simulium ( Trichodagmia ) sensu Crosskey and Howard, using 34 morphological characters of larvae (6 characters), pupa (5) and adults (23), yields nine most parsimonious trees under equal weights (length 101 steps CI 0.49 RI 0.73). Successive weighting based on the maximal rescaled consistency index preferred one of the nine (31.37 steps CI 0.62 RI 0.87 total fitcon3= 235.8), which was also one of two trees found under implicit weights with concavity values of 3–6. The cladogram justifies the recognition of two subgenera. Simulium ( Trichodagmia ) sensu stricto (containing S. muiscorum, sumapazense, S. wygodzinskyorum, S. nigrimanum, S. chalcocoma, S. huairayacu and S. lahillei ) is supported by the branchial tip sclerotization and the presence of cibarial teeth, larval body tegument covered with lanceolate hairs, female with simple claw, and gonapophysis size. Simulium ( Thyrsopelma ) (containing S. scutistriatum, S. hirtipupa, S. orbitale, S. guianense, S. perplexum and S. itaunense ) is supported by the hypostomial teeth.  相似文献   

8.
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.  相似文献   

9.
15N T(1), T(2) and (1)H-(15)N NOE were measured for the thermophilic Fe(7)S(8) protein from Bacillus schlegelii and for the Fe(4)S(4) HiPIP protein from Chromatium vinosum, which is a mesophilic protein. The investigation was performed at 276, 300, and 330 K at 11.7 T for the former, whereas only the 298 K data at 14.1 T for the latter were acquired. The data were analyzed with the model-free protocol after correcting the measured parameters for the effect of paramagnetism, because both proteins are paramagnetic. Both thermophilic and mesophilic proteins are quite rigid, with an average value of the generalized order parameter S2at room temperature of 0.92 and 0.94 for Fe(7)S(8) and Fe(4)S(4) proteins, respectively. The analyzed nitrogens for the Fe(7)S(8) protein showed a significant decrease in S2with increasing temperature, and at the highest temperature >70% of the residues had an internal correlation time. This research shows that subnanosecond rigidity is not related to thermostability and provides an estimate of the effect of increasing temperature on this time scale.  相似文献   

10.
Twelve species are described, of which two are new, viz. Spirorbis (Janua) gnomonicus and Spirorbis (J.) parvulus, and three others have been recognized only very recently, viz. S. (Pileolaria) clavus, S. (P.) endoumensis, S. (P.) heteropoma. Some such as 5. (jf.) corrugatus and S. (P.) koehleri were widely distributed between depths of 0–60 m, but others showed a tendency towards depth zonation, with S.(J.)pagenstecheri abundant in shallow and S. (Spirorbis) cuneatus in somewhat less shallow water. 5. (P.) pseudomilitaris and S. (Marsipospira) striatus were confined to greater depths except where the former occurred amongst ships fouling and the latter in a dark cave. 5. (P.) militaris seems rather uncommon.
A remarkably high percentage of the species (over 80%) are opercular incubators. Outside the Mediterranean, the only areas known to have similar percentages are Ceylon and the West Indies, suggesting that the habit may have originated in the Sea of Tethys.  相似文献   

11.
Yanagisawa A  Asakawa K  Yamamoto H 《Chirality》2000,12(5-6):421-424
(S,S)-Ethylenebis(tetrahydroindenyl)titanium chloride methoxide, (S, S)-(EBTHI)TiCl(OMe) (3) was synthesized from the corresponding titanium dichloride. The asymmetric aldol reaction of enol trichloroacetate of cyclohexanone 1 with aromatic aldehydes was studied in the presence of a catalytic amount of the chiral titanium complex 3, with the result that the optically active syn aldol adduct 2 was preferentially obtained with up to 91% ee.  相似文献   

12.
For the rational design of a stable collagen triple helix according to the conventional rule that the pyrrolidine puckerings of Pro, 4-hydroxyproline (Hyp) and 4-fluoroproline (fPro) should be down at the X-position and up at the Y-position in the X-Y-Gly repeated sequence for enhancing the triple helix propensities of collagen model peptides, a series of peptides were prepared in which X- and Y-positions were altogether occupied by Hyp(R), Hyp(S), fPro(R) or fPro(S). Contrary to our presumption that inducing the X-Y residues to adopt a down-up conformation would result in an increase in the thermal stability of peptides, the triple helices of (Hyp(S)-Hyp(R)-Gly)(10) and (fPro(S)-fPro(R)-Gly)(10) were less stable than those of (Pro-Hyp(R)-Gly)(10) and (Pro-fPro(R)-Gly)(10), respectively. As reported by B?chinger's and Zagari's groups, (Hyp(R)-Hyp(R)-Gly)(10) which could have an up-up conformation unfavorable for the triple helix, formed a triple helix that has a high thermal stability close to that of (Pro-Hyp(R)-Gly)(10). These results clearly show that the empirical rule based on the conformational preference of pyrrolidine ring at each of X and Y residues should not be regarded as still valid, at least for predicting the stability of collagen models in which both X and Y residues have electronegative groups at the 4-position.  相似文献   

13.
Traditionally, biostratigraphy of the terminal Famennian (Upper Devonian) and lower part of the Tournaisian (Mississippian) is based on phylogeny of the conodont genus Siphonodella Branson and Mehl. This study is focused on a Siphonodella species with a long taxonomical history. For the last three decades it was known as S. hassi Ji, 1985 and was used as a zonal index for the eponymic hassi Zone, used worldwide. However, this species faces several taxonomical problems. The main issue is the homonymy of S. hassi and S. cooperi hassi Thompson and Fellows, 1970. However, S. cooperi hassi is a subjective junior synonym of S. obsoleta Hass, 1959. The oldest junior synonym of S. hassi is S. wilberti Bardasheva, Bardashev, Weddige and Ziegler, 2004, and, according to a statement by the International Commission on Zoological Nomenclature, the latter represents the only available name for this species. An additional problem is the similar morphology of early ontogenetic stages of S. wilberti and S. quadruplicata Branson and Mehl, 1944, the youngest stratigraphically important siphonodellid species. In advanced ontogenetic stages, P1 elements that possess two rostral ridges belong to S. wilberti only. The smaller P1 elements having two or less rostral ridges comprise the S. wilberti- S. quadruplicata plexus. Maintenance of the wilberti Zone in the Tournaisian global zonation is suggested.  相似文献   

14.
We recently detected specific high-affinity binding sites for 12(S)-HETE, the main arachidonic acid metabolite in skin, on epidermal cells. The putative receptor is involved in keratinocyte chemotaxis toward 12(S)-HETE, which points to its participation in wound healing. In an effort to further characterize the 12(S)-HETE receptor, we investigated its regulation by various cytokines. Of the tested cytokines, only interferon (IFN)-gamma led to a massive induction of the 12(S)-HETE receptors. The effect was dose and time dependent and blocked by cycloheximide. The up-regulation of 12(S)-HETE receptors by IFN-gamma may represent an amplification mechanism of the assumed role of 12(S)-HETE in skin wound repair.  相似文献   

15.
Eight specimens of Sericolophus reflexus (Ijima) were compared with the holotype of Hernandeziana ijimae (Hernandez) to assess suspected synonymy of these taxa. An extensive morphometric analysis of the spicules available in these specimens of variable condition show that the H. ijimae holotype exhibits characters near the centre of the range of S. reflexus. It is concluded that H. ijimae is a junior synonym of S. reflexus , and that the family Corythophoridae de Laubenfels is invalid by preoccupation of its base generic name.  相似文献   

16.
刘德旺  张树仁 《西北植物学报》2007,27(11):2320-2322
发现了分布于西藏的2个珍珠茅属新记录种:小型珍珠茅和毛果珍珠茅,并补充记载了2个新记录种的文献和标本引证。  相似文献   

17.
Heteroligand copper(I) complexes of bi- or bis-bidentate acylamidophosphates PhC(S)NHP(S)(OPr-i)2, PhC(S)NHP(O)(OPr-i)2, Et2NC(S)NHP(S)(OPr-i)2, PhNHC(S)NHP(S)(OPr-i)2, N-(4-aminobenzo-15-crown-5)-C(S)NHP(S)(OPr-i)2, N,N-(1,10-diaza-18-crown-6)-[C(S)NHP(S)(OPr-i)2]2, and triphenylphosphine were prepared and characterised. Copper is bound by two PPh3 and one SCNPX (X = O, S) fragment of chelating ligand in all cases. Triphenylphosphine molecules reversibly dissociate in solution. Details of the X-ray structures of (Ph3P)2Cu[PhC(S)NP(S)(OPr-i)2] and (Ph3P)2Cu[Et2NC(S)NP(S)(OPr-i)2] are reported.  相似文献   

18.
Genetic divergence and variability at 14 enzyme loci were examined in and between Italian populations of two edaphic Oribatid (Acarida, Oribatida) species, Steganacarus (Steganacarus) magnus (8 populations) and S. (S.) hirsutus (1 population). The seven populations belonging to S. (S.) magnus can be divided into two groups according to their phenotype, form anomala (A) (MON, ARG, AST, CDO) and form magna (M) (MAL, MAM, RIF) while another can be considered as hybrid between the two preceding groups (ZOC). Genetic identity (I) values between the S. (S.) magnus populations in spite of their morphological differences ranged from 0.977 to 1.000 showing the great genetic similarity of simple local populations while those of S. (S.) hirsutus indicated two distinct morphological species. The genetic distances between all the populations examined were very low despite the ecological differences and geographical distances between the collecting sites. Genetic variability estimates in all the populations of both species were very low when compared to those reported for most arthropods. Some explanatory considerations are suggested.  相似文献   

19.
Shen Z  Chen W  Jiang H  Ding Y  Luo X  Zhang Y 《Chirality》2005,17(2):119-120
A novel proline derivative, (4R)-4-(beta-Naphthalenyl)methoxy-(S)-proline, was conveniently prepared from the naturally occurring (4S)-hydroxy-(S)-proline; 5 mol % of this compound efficiently catalyzes the asymmetric aldol reactions of various benzaldehydes with acetone in excess of acetone as the solvent, giving the aldol adducts in good yields with ee up to 89.8%.  相似文献   

20.
The 16 species of theSedum acre-group were investigated for the presence of alkaloids. They areS. acre ofS. ser.Acria, S. alpestre, S. annuum, S. apoleipon, S. borissovae, S. euxinum, S. grisebachii, S. laconicum, S. multiceps, S. sexangulare, S. tuberiferum, S. tuberosum, S. ursi, andS. urvillei ofS. ser.Alpestria, S. samium ofS. ser.Samia, andS. litoreum ofS. ser.Litorea. S. acre differs significantly from the other species. It contains sedamine, hydroxy sedamine, and a number of 2,6-disubstituted piperidine alkaloids. The leafy parts of the species ofS. ser.Alpestria, S. ser.Samia, andS. ser.Litorea contain 4 piperidine alkaloids which also occur inS. acre, and in addition 4 pyrrolidine alkaloids not present inS. acre. The composition of the alkaloid fraction agrees with the infrageneric classification (series) based on the hybridization patterns of the species (comparia).  相似文献   

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